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FILE NAME: Trade Publications (TR) DATE: 1936 Feb DOC#: TR012 DOCUMENT DESCRIPTION: Trade Journal - Mechanical Engineering John D. Roven Michael L. Kaplan Joe D. Wells Roven, Kaplan & Wells, L.L.P. attorneys and counselors at law 2190 North Loop West, Suite 410 Houston, Texas 77018-8008 Telephone: (713) 465-8522 Facsimile: (713) 465-3658 March 7, 2002 Mr. Steven Berger 4418 Pleasant Valley Court Oakland, California 94611 Barry Castleman, M.D. 2412 Pickwick Road Baltimore, Maryland 21207 Re: Mechanical Engineering, Volume 58, N o. 2; February, 1936 Dear Steven & Barry: Enclosed, please find a complete copy o f Mechanical Engineering, February, 1936 as requested by Barry. As you w ill see from the format o f the magazine, no advertising was accepted. There are interesting Articles by Warren Cook and Theodore Hatch. The article on Occupational D isease is written by an executive o f an insurance company. It contains the usual concerns about litigation, increased costs, etc. A t any rate, w e now know what the format o f "mechanical engineering" appears to look like. I have numerous other documents that are coming in from the American Society o f Mechanical Engineers and intend to share some relevant articles with you in the forthcoming days. The "Vapor" case is on the docket for trial in Los Lunas, N ew M exico in April, but at this point, w e are on a trailing docket and I have not received confirmation from the Court that w e w ill go. I promise to keep you posted as soon as I have better information. If you have any questions or concerns, please do not hesitate to contact me. Yours truly, ROYEN, KAPLAN & WELLS, L.L.P. JDR/mt Enclosure Jolui rCoftA, John Roven r(d: Volume 58 No. 2 MECHANICAL ENGINEERING GEORGE A. STETSON, Editor A.E.C. Forges Ahead member bodies have given an increasing measure o f at tention, as was attested in these pages some months ago, ARISING to the challenge of an unprecedented na under the practical and enthusiastic leadership o f Mr. tional emergency w hich had grave effects upon Feiker. The impression made upon those who listened engineers in particular, the American Engineering Counto the able reports read at Washington was so favorable cil. whose annual m eeting was held in W ashington, that no dissenting voice was heard protesting at further January 9 to n , demonstrated an effectiveness in dealing and more extensive work along these lines. The re with public and professional affairs that elicits the warm ports themselves had the virtue o f being informative and est praise. An .impartial observer o f the record o f the o f dealing w ith principles and policies rather than de last few years o f effort and accomplishment on the part tails. The individual w ho belongs to one of the many of the Council w ill agree that it has justified the high member organizations that make up the Council has hopes of its founders and proponents, silenced many o f the satisfaction o f knowing that the negligible amount its critics, advanced the cause of unity in the engineering o f his personal monetary contribution to the work of profession, made distinguished contributions to the the Council pays high dividends in social and profes intelligent administration of government agencies on sional values. a nonpartisan basis, assisted engineering groups and So effective is the Council's work, and so high its individuals, and enhanced th prestige of the profession, prestige, that contributions to its activities could easily especially in official circles at W ashington. be obtained were it to consent, to further special and less Backed by the loyal support o f the many member public-spirited interests. But the Council wisely realizes organizations, the president, John F. Coleman, the staff, that any such change in its policy would bring it and the headed by Frederick M. Feiker and his assistant L. V. engineering profession into discredit and frustrate its Reese, and the several important committees, in particu services to engineers and to the country. Only by fol lar those groups under the Public Affairs Committee o f low in g the course it has set for itself under such intelli which F. J. Chesterman acts as chairman, have succeeded gent leadership as its eminent officers have given it can splendidly in concrete accomplishments and in the con it retain the confidence of those in public and private tributions to sound and intelligent opinions and state life that look to it for advice and assistance. If every ments of policy on many matters affecting the public as engineer w ill continue to back it up, the Council w ill con well as engineering interest. To these individuals, and tinue to forge ahead in the service and to the honor of to all w ho worked w ith them, the thanks o f the entire the. profession. profession is due. If intelligent and enlightened self-interest is an effec tive means of securing the public interest--and to this A Timely and Significant G ift thesis w e have continually adhered-- the American Engineering Council has set an example w h ich other organizations representing important minorities should follow. For it is unfortunately true that many such THE bicentennial celebration of the birth o f James W att, recently held at Lehigh University and The Franklin Institute, makes unusually appropriate the organizations think of themselves in terms w hich pro mote their ow n selfish interests at the expense of other groups or o f the public welfare in general. Contrary to this attitude is that of the American Engineering Council w hich seeks, among other objectives, to render the best services it can in the public good by a critical, nonpartisan examination, frequently w ith the result of providing expert opinion on matters o f public concern that aids in the proper planning or execution of impor tant legislation; for as a class engineers are convinced that their own best interests are at one w ith the public's. To this aspect of the work of the Council, its execu tive committee, its Committee oh Public Affairs, and its generous gift of the American Society o f Civil Engi neers to The American Society of Mechanical Engineers o f a marble portrait bust o f that famous engineer, a photograph of which faces this page. This bust, con stant reminder o f one of the early masters of engi neering, now becomes a cherished possession o f the A .S.M .E . In the terminology of his day Watt was a civil, as distinguished from military, engineer. But his work laid the foundation upon which mechanical engineering has since been based. In this connection it is fitting to recall here that the Institution of Civil Engineers (Great Britain) was formed 73 74 M echanical Engineering one year before the death of W att and incorporated years later in 182.8. It is said that denial o f member ship in that society to the famous locom otive and rail road builder, George Stevenson, led to the formation in 1849 o f the Institution o f Mechanical Engineers, o f w h ich he was the first president. Thus a century ago was begun that decentralizing influence among practitioners in the engineering profession which ex tended to this country and resulted in the formation of our numerous societies devoting their energies to ex clusive branches of engineering. Happily today that influence is abating, as incidents too numerous to men tion amply testify; and in this country w e find the major societies amicable neighbors under a single roof, jointly engaged in activities that tend to draw them more closely together. O f this significant spirit the gift o f th e American Society of C ivil Engineers is but one o f many happy reminders that distinctions based on fields o f practice are disappearing in the realization of the common heritage and interests o f all engineers. in earnings, but have not experienced the same recovery. As to functions performed, one-quarter of the Indiana engineers replying to this question of the survey were in design, another quarter in construction, although not all were in the construction industry, and slig h tly less than one-third were in operation. Nine out of ten got their jobs as a result of personal contacts. Few engineers in Indiana are engaged under long-time contracts, and contracts w ith " separation" clauses are relatively unimportant. As to pensions, 80 per cent enjoy no pension rights, but of those w ho do, half are on a contributory basis. These sketchily presented results, representing one state only, are just enough to w het the interest in the complete details and to suggest numerous facts o f use to engineers, individually and collectively, in planning careers and programs for the benefit o f the profession. News of A.S.M.E. Affairs Engineers' Status in Indiana A COMMON source o f misunderstanding in all society work is lack o f knowledge o f w h at is going on, w hat plans are contemplated, and w h at results MA N Y readers w ill remember having filled out, have been achieved. In a national society w ith member several months ago, a questionnaire prepared by ship running into the thousands the problem o f keeping the Bureau of Labor Statistics o f the U. S. Departmentmoefmbers posted is a serious one and requires reciprocal Labor for a survey o f the engineering profession, covering effort. Officers and staff must find ways o f disseminating facts on employment and income, and designed to throw news o f society affairs; members must accustom them light on the incidence o f the depression on members of selves to the channels through which it is sent to them. the profession. The first intim ation o f w hat the results W ith the exception o f certain types of society news m ight be was divulged at the m eeting o f the American that, for one reason or another, are sent out in the form Engineering Council by Isador Lubin, Commissioner o f o f letters to the individual members, most information Labor Statistics, w h o presented som e o f the statistics for must be made public through official publications. In the State o f Indiana, the only state for w hich figures are The American Society o f Mechanical Engineers M e as yet available. chanical Engineering is the medium through which A lthough it was expected that com plete results would the members are apprised of "w h at's going o n ," and be available earlier than this, no less than eight other this familiar catch-phrase has, for several years, been surveys, most of them involving much more work, have the name of the news department of this magazine. since been undertaken by the Bureau, and because of the " W hat's Going O n" w ill be found in the final text nature o f the agencies w hich they are to serve, have pages of every issue o f Mechanical E ngineering. Ex been given priority. But the few facts on the engineer's cept for the fact that the Society's interests make it status in Indiana are o f interest, even though they ,may desirable to include somewhere in its monthly journal not be typical o f other states or the country as a w hole. items that are not strictly confined to the Society's That frequently made assertion that great numbers activities, this department might be called " A.S.M.E. o f men educated as engineers find employment in other N ew s," or "Society Affairs." The more general title lines o f w ork is not borne out by the Indiana results, does not exclude important releases, such as news o f the w hich show that men tend to stay in the fields of their E.C.P.D., of the American Engineering Council, and of specialty. A. trend w as noted toward a smaller percent other related organizations in which A.S.M .E. members age o f engineers in private employment and a greater have interests. percentage in government positions, particularly in the Because from time to time A.S.M .E. members plead service o f the state. Practically no change was noted in ignorance o f w h a t's going on after announcements and the percentage of men in the teaching profession. The reports have been published by the Society, attention is trend, in five years, from engineering to nonengineering, called to this news section o f M echanical Engineering. particularly in the case o f young graduates, was expected. Members o f the Society should turn to it every month In so far as the relation o f education to salaries is in order to keep in touch w ith Society affairs, for until concerned it was shown that there was a substantial decrease in earnings from 19x9 to 193X, and, for college graduates, an increase, though not to 19x9 levels, from 193X to 1934. Nongraduates suffered similar decreases the Council has the necessary funds to set up an inde pendent house organ, there exists no other convenient means o f distributing A.S.M .E. news. Regular reading, of this department w ill save many misunderstandings. JAMES W ATT 1736-1819 By GEO. A. ORROK CONSULTING ENGINEER, NEW YORK. N. Y. IT IS difficult for modern Americans to picture to themselves the state 'of society and the arts in Great Britain in 1736. Pepys and Evelyn matician" and "teacher of naviga tion," had come to Greenock from Aberdeen. Thomas'second son, James W att, born in 1698, a ship carpenter, have painted intimate pictures of the chandler, and merchant, married in state of the country from the Restora 1729 Agnes Muirhead, a woman of tion to the flight of James. Macaulay, superior intellect and force of char in his famous "third chapter," has acter, and to them- was born Jamie shown us the country and the people W att, whose birthday we are celebrat in 1700, while Trevelyan ably covers ing today. It is reported that he was the period of the third George, the delicate, but it is certain that in the first English Hanoverian king, in which our interest today is centered. The population of Britain at the time face of the cold and wet Clydeside winters he managed to grow to man hood without serious illness and to of the Act of Union was small, not ex absorb what knowledge he was able to ceeding 5,500,000, but many changes get from his mother and father, his in British life and industry had begun and grew rapidly, introducing an en tirely new phase into the life and ac schoolmasters, and his fellows in the busy trading town of Greenock, which was the Clyde port at that time and one tivities of the people. The change of the chief centers of the tobacco trade. from adventure trading to corporation trading, the shifting of the banking W ATT, THE MECHANIC business from the Goldsmiths' Guild to With this mechanical ancestry it was the newly chartered Bank of England, only natural that Jamie Watt should the institution of the National Debt, take to tools and want to make the formation of the East India Com pany and other trading companies, the reinvention by Abraham Darby of the use of mineral fuel instead of charcoal W EDGEWOOD REPLICA OP CHANTRY BUST OF WATT (Presented to A.S.MJE.byErwinGraves, 1892.) things, and very early he had a work room and forge in a corner of his father's shop where he did those parts of the shipwright's work that could in the manufacture of iron, and the be done at the bench. George William gathering of the home industries into factories were all signs son, who left for us the account of W att's early years, says he of a changed social and industrial order. Bridgewater, Brind became quite expert in so many lines that his shopmates had ley, and others were planning and building canals, and a real a saying that ``Jamie has a fortune in his fingers. '' Among his road-making campaign was being instituted. Despite foreign other successes was a model of the crane, which had just been wars and the panic of 1720, the population increased steadily, built for unloading the tobacco ships at Greenock, and a barrel and it was in the breathing spell between the last Stuart organ. and the first English Hanoverian sovereign th a t James Watt His mother died in his eighteenth year, a great loss to him, was born in Greenock, Renfrewshire, near Glasgow, two hun for they were most sympathetic, and shortly after he visited his dred years ago. mother's brother in Glasgow, then a quiet university town. George HI was born in 1738, two years after James W att, and He worked there w ith an optician for nearly a year, and when came to the throne in 1760 when W att was 25 years old. In the he was nineteen his uncle advised him to go to London to learn first six decades of the eighteenth century only about 1,500,000 the trade of a mathematical-instrument maker. In London, people had been added to the population, but the 7,000,000 of after much difficulty, he induced John Morgan, who had a shop 1760 were to become 14,000,000 by the time the work of these in Cheapside, to take him on as a journeyman, paying Morgan two men was finished and Britain had been remade. In the 20 for the privilege. In a year he learned all that the Morgan words of Trevelyan, "W ith iron and machines was bom a.new shop could teach him, and in 1756, when he was 20 years old, he class, the modern mechanic." And as the last Stuarts and the returned to Glasgow and set up as an instrument maker. The Hanoverian kings saw the influence of parliamentary govern University gave him quarters in the quadrangle, a not unusual ment steadily grow and the influence of kings decline, so iron practice, and here he came into contact w ith Dr. Dick, Dr. and power to drive machines made possible the modern me Joseph Black, Dr. Roebuck, and a young graduate, John Robi chanical world w ith its higher standard of living and its greater son, who became his lifelong friends. comforts and possibilities for the individual mechanic. The grandfather of James, Thomas W att, listed as a " mathe- WATT, THE EXPERIMENTER An address delivered at the Bicentenary of Watt, Lehigh University, Bethlehem, Pa., January 20, 1936, under the auspices of the University, The Franklin Institute of Pennsylvania, the North American Branch of The Newcomen Society of England, and T h e A m erica n Society of Mechanical E n g in ee r s. It was here at the University that he started his work repair ing the philosophical instruments of the department of natural philosophy. He continued his experiments on all sorts of things, including work on the pressure and temperature of water, which led to his trying high-pressure work with a Papin 75 M echanical Engineering ? caused Watt to borrow the funds from his good friend and ad viser, Dr. Black, to carry on his steam experiments. The loss of his partner, Craig, and the consequent withdrawal of his capital, made it necessary for Watt to seek additional income, and this he found by setting up as a surveyor. In 1766, with Roger Mackell, he contracted to survey a canal from the Firth of Forth to the Firth of Clyde. This work was completed and the report was printed in 1767, and Watt went to London to see ; i- tBhreidgbeilwl attherrouangdh CPaalrdleiarmCeannt.als.OnAhsisthreetwurinntehrewvaissitaedslathcke time in the canal business, W att turned back to the engine, and his experiments so impressed Dr. Roebuck that Roebuck agreed to pay W att's indebtedness to Dr. Black, the cost of the patents, and to become a partner w ith Watt, taking a two-thirds interest in his engine experiments; so Watt in July, 1768, went to Lon don, and on August 9 took oath on his first steam-engine patent embodying the separate condenser. On his way back to Glasgow he stopped at Birmingham and stayed for two weeks with M atthew Boulton. The tw o be came very good friends, for, although they were opposite in character, they were sympathetic in many of their ideas and ideals. Watt told Boulton most of his hopes for the engine; and as Boulton became equally enthusiastic and offered to buy w a t t 's t ir s t r o t a r y e n g i n e in to the partnership, Watt agreed to put the proposition up to (A, steam cylinder; B, steam pipe; C, throttle valve; D, steam valve; E, eduction valve; F, eduction pipe; G, valve gearing; H, condenser; I, air pump; K, air-pump rod; L, foot valve; M, hand-gear tappet rod; N, parallel motion; 0, balance weight; ?, rocking beam; 0, connecting rod; R, feed pump rod; L, sunwheel; T, planet wheel; U, flywheel; if7, governor; X, feedwater cistern. Illustration is from Smiles's "Lives of Engineers.") Dr. Roebuck. On arriving home, Watt started work on an 18 in. by 6 ft inverted cylinder to prove his engine patents. This engine was erected at Kinneil after a considerable delay. Roe buck's offer to Boulton was only a license for the Midland coun ties, which interested Boulton not at all, so the matter was dropped for the time. digester. This he finally threw aside because of the explosion hazard. In 1759, he went into partnership w ith John Craig in It was about this time that Watt invented a method of stadia surveying which was to be of great use in his work later on. 1 the mathematical-instrument business and opened a shop in the Saltmarket, St. Andrew's Street. He did more or less manufac turing, and, among other things, made reed organs. In 1763 he bought an interest in the Delftfield Pottery Com pany which made a good grade of white stoneware. He kept his connection w ith this pottery company for many years, ex perimenting on kaolin, on furnaces, and in other cognate lines. Later, Dr. Black and Dr. Roebuck interested him in an alkali fsp it, Y manufacturing scheme, and he made for them many experiments covering the process. In July, 1764, he married his cousin Margaret Miller, w ith whom he led a happy life for nine years. Four children were born to her during those years. * ; WATT, THE Civil, ENGINEER ' In 1765 he invented a perspective drawing machine which had a wide circulation, as the machine was a really good one and W. " M the price was reasonable. Prof. John Anderson in this year commissioned him to repair the Newcomen engine model owned by the University. W att had made many experiments on boil ing water and steam and particularly on the temperature of water boiling under pressure. He learned from Dr. Black about latent heat, and measured the expansive force of steam, and in May, 1765, he had solved the problem of the Newcomen engine. His solution consisted in separating the condenser from the cylinder. The invention of the steam jacket and sepa rate condenser kept the cylinder hot and the condenser cold. 1 ti The experimental apparatus is to be seen in the South Kensing ton Museum. The first condenser was of the jet type, but in other experiments W att invented the surface condenser, and he H' also closed the top of the cylinder and applied the stuffing box, making the engine double acting. WILLIAM MURDOCK These experiments took the better part of two years. During (From an Oil Painting by Graham Gilbert at the Birmingham iJ-: this time his partner, John Craig, died, and financial difficulties Art Gallery.) February, 1936 77 w a t t 's g a r r e t w o r k s h o p a t h e a t h f i e l d His engine experiments, which he carried on between surveys, included a tubular surface condenser w ith two air pumps. His work on the engine was stopped for a while by a survey of the Firth of Clyde for the City of Glasgow, which contemplated getting sufficient water to accommodate ships of some size. He also surveyed a route for the Lanarkshire Canal from the coal fields to the City of Glasgow, from which company he drew 200 pounds per year as chief engineer until 1772. The survey for the Strathmore Canal was put through at this time. Then came plans for docks and harbors at Port Glasgow, the Canal at Crinan, and the one at Tarbet. In 1772 he was com missioned to survey a water supply for Greenock, and he built two reservoirs for the city, one of which is still in use. In 1773 he made surveys for five shorter canals and also started the sur vey for a canal between Inverness and Fort William, now the Caledonian Canal, on which his stadia method was used. About this time he used a screw to control a dividing engine for making scales. BOULTON ENTERS THE PICTURE During 1772-1773 a financial panic swept over Britain and -Watt's partner, Roebuck, who was concerned w ith iron works in Stirlingshire and other chemical works in the Black country, had to go into bankruptcy and his property was taken over by creditors. The creditors, however, placed little or no value on the engine a t Kinneil, and in July, 1773, Boulton bought out the two-thirds partnership from Roebuck's creditors, thus becom ing W att's partner. About this time also, W att was called home from his canal work by the sickness of his wife, only to find on his arrival in Glasgow that she had died the day before. His discouragement following the violent uprooting of his home made him ready to drop everything and join Boulton in Birmingham, but the Caledonian Canal report had to be finished and a survey of the Upper Forth needed completion, all of which work he finished by May, 1774, when he left Glasgow w ith his family for Birmingham, which was to be his home for the re mainder of his life. W att was now in his thirty-ninth year and his struggles were at an end. He had been a timid and rather sickly boy who had feared the fight for a place in the world and so he had kept himself more or less cloistered in the University. He was, by dire necessity, dragged out of this sheltered field to undertake the civil-engineering work on the canals which had been his main source of income for six years, but he hated business and bargaining. He did not enjoy commanding men and his best work was done as an experimenter, working alone where he could give all of his mind to the subject in question. He now had in Matthew Boulton an efficient business partner, who was a financier as well as a manufacturer and who had faith in what W att could do and in the future of his inventions. We have many examples of men who experimented and em bodied the results of their labors in a machine. We may recall Worcester, Savery, Papin, whose digester was used by W att, Dud Dudley, and the Darbys, all of whom experimented to a greater or less extent on their inventions. W att's friend, Dr. Joseph Black, experimented to a degree, but we also remember the Royal Society arguments about the brimming pail of water and the live fish. It was after years of Aristotelian reasoning that some unknown doubter suggested that the experiment be tried, settling the controversy forever. W att was an experi menter. Starting w ith models, then quantitative as well as qualitative trials of materials, and of chemical, and physical changes, and, eventually broadening to a very wide field indeed, he was one of the first, if not the first, example of Trevelyan's new class, the modern mechanic. " THE MODERN MECHANIC' ' AS W ELL AS THE ENGINEER But he was even more than a mechanic. His incursions into optics, physics, chemistry, and above all his passion for measur ing results with accuracy, set him apart from the other inven tors of the time who perhaps were content w ith qualitative re sults alone. He commenced to make accurate engine tests in 1774, and his notebooks show he kept this up until he retired from the engine business. His civil-engineering work also betrays this love for accuracy, and it is known that Telford in 78 Mechanical Engineering later years finished the Caledonian- Canal w ith only minor changes from W att's plan. W att's fertility in expedient, never shown so well as in little things like the dividing machine or the parallel motion, blos somed under the university environment and the encouragement of good friends like Black, Robison, Boulton, and Small. He did not readily collect and use assistants and understudies, probably because he had the urge to feel w ith his own hands the actual thing he was thinking about, and many good leads were left unraveled becaused of the lack of time, health, and the necessity for earning a living. Organized research w ith trained assistants was to come later. W att's civil-engineering work is not so generally known, but its quality was so good that there is little doubt he would have taken a, high rank in the profession if his early love, the steam engine, and his friend Boulton had not effectually prevented its continuance. BOULTON AND WATT Watt, w ith what was left of his family, his sister and two children, and his tools and belongings arrived in Birmingham on June 1, 1774, where he immediately proceeded to set up the Kinneil engine, w ith its block-tin cylinder, in a corner of Boulton's shop. And here he threw himself into the solving of his worst trouble, the piston packing. He tried many things from pasteboard to metallic packing. The block-tin cylinder collapsed and was replaced by an iron cylinder furnished by Wilkinson who had just invented the boring bar and could furnish a truly cylindrical cylinder which greatly helped the solution o f the packing difficulty. His other trouble was the patent situation. The partners determined to try to secure an extension of the original patent rather than to risk taking out a new one. After much trouble and appearances before Parlia ment, on May 22,1775, the patent of 1768 was extended for 25 years and was made to cover Scotland as well as England. Shortly afterward, on June 1,1775, Boulton and Watt entered into the famous partnership agreement that was to last till the expiration of the patent. By its terms Boulton was to assume all past obligations, furnish all moneys, and keep the books, taking a two-thirds' interest in the profits. Watt was to fur nish all drawings, give directions, and make surveys for which his remuneration was to be 300 per year. I t is doubtful that the papers were ever drawn up and executed, but that did not matter w ith two such men as W att and Boulton. The firm was now in working order and the two first engines were a 50-in. cylinder pumping engine and a 38-in. diameter blowing engine, which were rapidly put through the shops and erected. These engines were started about March, 1776, and were satisfactory, despite troubles w ith packing. In the sum mer W att revisited Glasgow and married his second wife, Ann MacGregor. His notebook contains this entry: " I con sider this as one of the wisest of my actions." THB ROTATING ENGINE The Cornish orders now began coming in and for the next five years the works were busy w ith pumping engines for de watering the deep Cornish mines. W att spent much of his time in Cornwall, having a house at Redruth. In 1777, Boul ton hired Murdock to aid W att as draftsman and later in erecting and testing. It is said th at Boulton hired him be cause of an oval wooden hat Murdock had turned out on a lathe of his own construction. Murdock proved to be a very valu able man indeed as he later became a partner in the firm. By 1780, the partners saw light and were able to show profits which increased as the years went by. The pumping-engine market continued, but the partners had been considering entering the millwork field and competing w ith the water wheels and " horsepowers." In 1780, the ac tual work on this type of engine was started. Watt did not be lieve the crank was patentable, but Pickard had secured a patent on a crank in combination w ith a wheel and bob weight's in 1780. So W att in 1781 patented five ways of securing rotative motion from reciprocating motion, among them the sun and planet gears, the only one of the five that was actually used. Engines w ith this type of crank followed each other in rapid succession. In 1782 Southern was hired as W att's assistant and draftsman. He proved to be as much of an acquisition as Murdock and later he also was admitted into the famous partnership. In the 1782 patent W att had included expansive working and the double-acting engine and these improvements necessi tated some means of guiding the piston-rod head which had been hung from the beam end sector by a chain. To end this trouble he invented the parallel motion which he fancied.more than any other of his inventions. W ith the pantagraph which completed it, it was a beautiful invention and was patented in 1784. Mention must be made of the Albion Mills engines for the steam flour mill for which the firm took the contract for supply ing the machinery and for which John Rennie undertook the erection. These engines were very successful and the mill worked well for three years, when it was destroyed by fire. In 1788 the application of the governor was patented and 1794 saw the invention of the indicator, Mention should also be made of the copying press, an invention which was made about 1778 and has been in use until the invention of typewriter car bons put letter-press copying into the background. The Pick ard-crank patent expired, in 1794, and all of Boulton and W att's later engines used this device. w a t t 's RETIREMENT---- HIS INFLUENCE In 1799 Watt retired to his estate at Heathfield and the sum mer estate at Doldowlod on the Wye in Radnor, Wales, where he lived the life of a country gentleman. He and his wife traveled to some extent on the Continent and revisited Corn wall and Scotland. He made many new friends and retained his interest in science and art but avoided ostentation. He re ceived the honorary degree of doctor of laws from the Uni versity of Glasgow, but refused a baronetcy and election as high sheriff of the counties of Stafford and Radnor. In his later years W att was afraid of losing his mental powers, and therefore took up the study of languages again, w ith great success, to make sure his brain was working. He was greatly pleased when in 1810 (75 years old) his plan for a flexible water pipe under the Clyde was accepted by the Glasgow Water Works. He would take no fee but was presented w ith a silver service by the corporation. Watt had a workshop in an attic room at Heathfield where he continued to work and use his active mind in all sorts of experi ments. When Heathfield was torn down this room was set up, exactly as it was at W att's death, in the South Kensington Museum, where modern generations may see his last works, the tools w ith which he worked, and the surroundings. The parallel motion still lingered in his mind, and a survivalof the perspective-drawing machine as well, for he was at work during the last years of his life on a pantagraph device for copying medals and sculpture, The tools in their drawers, chemicals in jars, jigs and models are reposing in their ordered disorder just as he left them. It is given to but few individuals to be of great use to their fellowmen and among these few W att takes high rank. 'His. use of the experimental method, his urge for accuracy, his wide February, 1936 79 curiosity which led him into all sorts of problems, and his in He died at his home, at Heathfield, on August 12,1819, in his ventive genius all combined to overcome the defects of ill eighty-fourth year, after a short illness. He was buried in the health, lack of perspective, and the difficulties of earning a Handsworth Parish Church beside his friend and partner Mat living in the epoch of great changes in which he lived and for thew Boulton. His fame as an inventor and scientist continued which he was partly responsible. to increase and receive public recognition. A statue by Chan Pessimistic to the extreme in his earlier years, he mellowed try, paid for by public subscription, was set up in Westminster with age and the improvement of his finances. He made Abbey in 1824, and I cannot better close this appreciation than friends easily and kept them. Diffident and unostentatious, by quoting the inscription on the base of the statue, written widely interested in a great variety of subjects, he conducted an by Lord Brougham, and said to be the finest lapidary inscription increasing correspondence and contrived to avoid entangle in the English language: ments in the political field so attractive to many at that time. Living as long as he did he had the disadvantage of seeing his good friends pass away one by one, but while regretting their passing he jbqcame more interested in the doings of the younger Not to Perpetuate a Name Which Must Endure While the Peaceful Arts Flourish But to Show That Mankind Have Learned to Honour Those generation. It is difficult to rank his inventions. He himself fancied the parallel motion. I am inclined to believe the recognition of the expansive force of steam was the high point of his endeavors, Who Best Deserve Their Gratitude, THE KING, His Ministers, and Many of The Nobles and Commoners of The Realm, Raised This Monument to JAMES WATT, and this was followed closely by the separate condenser and the stadia method of surveying. His work in the pottery field was sound but not spectacular, and the friendship w ith Wedgewood was a proof of good work in ceramics. Who, Directing The Force of An Original Genius, Early Exercised In Philosophic Research, To The Improvement of THE STEAM-ENGINE, Enlarged The Resources Of His Country, Increased The Power Of Man, I have said little of the litigation made necessary by the patent monopoly but from 1782 to 1799 a large portion of Watt's time was taken up w ith this protection of the partner ship rights. And Rose To An Eminent Place Among The Most Illustrious Followers of Science and The Real Benefactors Of The World. Born at Greenock, MDCCXXXVL DIED At Heathfield, In Staffordshire, MDCCCXIX. JAMES WATT AT THE AGE OP 71 FROM THE ORIGINAL PA IN T IN G BY PARTRIDGE BELONGING TO THE ESTATE OF JOH N SCOTT, ESQ., OF H A W K H ILL, GREENOCK (From a photograph in the files of T he A m erica n Society of M echanical E n g in e e r s.) fri UNIFLOW ROLLING-MILL ENGINE (Four-cylinder condensing. At 45 per cent cut-off will develop 14,000 hp and will develop 30,000 hp at maximum. Built by Nordbcrg Manufacturing Co., for Wheeling Steel Corporation, Stubenville. Courtesy Nordberg Mfg. Co.) THE STEAM ENGINE in the NINETEENTH CENTURY By DEXTER S. KIMBALL CORNELL UNIVERSITY, ITHACA, N. Y. THE steam engine as conceived by its inventor and his contemporaries was, of course, a rather crude machine, but even before W att's passing it had been applied successfully to a variety of purposes, such as pumping and end of the nineteenth century it had reached its maximum of size and efficiency and with the appearance of the steam turbine and the internal-combustion engine its place in industry has been challenged. It may be helpful in visualizing its growth driving mill machinery, and engineers and inventors were busy to follow its rise in a few of its major applications. trying to adapt it to the problems of transportation both on land and water. It was soon seen th at the original form of the MINE PUMPING engine was not naturally suited to all purposes, and the first One of the first applications was to mine pumping, and out ;lr. fifty years of the last century was a period of experimentation, of this came the Cornish pump. In this pump a heavy pump adaptation, and elimination, out of which has come a few rod is suspended from a " bob" or rocker, the rod carrying well-recognized types of engines and a few valves, valve gears, vertical plunger pumps at convenient intervals; in deep mining and other auxiliary devices, the combinations varying in about 300 ft apart. The engine lifts the rod by oscillating the different lines of work. The various forms of governors, slide bob and the weight of the rod is sufficient to perform the valves, Corliss valves, and link motions are all survivals of the pumping. In the Watt engine the beam itself acted as a bob. fittest from fifty years of experimentation. Dr. Thurston This simple and effective device was imported into this country remarks: "By the middle of the present [nineteenth] century, and was developed to a remarkable degree in the deep mines the steam engine had been applied and successfully to every of the Comstock Lode at Virginia City. The accompanying great purpose for which it is fitted. Its first application was illustration shows such an engine developed as these shafts to the elevation of water; it next was applied to the driving sank to a maximum depth of about 3000 ft. of mills and machinery; and it finally became the great pro In the early pumps the bob was driven by a small engine pelling power in transportation by land and sea." By the geared to the driving mechanism, but as greater depths were reached large compound horizontal or vertical engines were An address delivered at the Bicentenary of James Watt, Lehigh University, Bethlehem, Pa., January 20, 1936, under the auspices of the University, The Franklin Institute of Pennsylvania, The North Ameri can Branch of the Newcomen Society of England, and T he A merican Society of M echanical E n g in eers. connected directly to the pump bob. These engines were of two distinct types. In one no flywheel was used but an elaborate " Davy differential" valve gear insured th at the pistons followed full stroke. In other engines a flywheel February, 1936 85 attached by crank and connecting rod to the bob insured con tinuity of action and full stroke. A number of these Com stock pumps attained great size. Thus the pump at the Union shaft, an illustration of which is shown, was operated by a flywheel engine w ith compound noncondensing cylinder 64 by 81 in. and 100 by 99 in., coupled directly to the bob. The pump rod was of Oregon fir, 16 in. square, spliced at the joints, and reinforced with heavy wroughtiron straps through out its length. The rod o p e ra te d a double lin e of plunger pumps 15 in. in diameter w ith a 7 ft 6 in. stroke, making about six strokes a minute. This pum p was erected some time in the 1880's and it represents the limit of pumping by the Cornish system. It is to be regretted that lack of space pre vents a description of the pumping en gine as developed for municipal and indus trial pumping. m in e h o istin g Another early ap plication of the steam engine was to mine hoisting. All arc fa miliar with the small geared hoist to be seen wherever weights of moderate size are to be handled through moderate dis tances. But the steam hoisting engine has attained its greatest size and efficiency in deep-mine work. Up to moderate depth (1200 ft) the geared hoist is quite satisfactory and the illustra tions show a few examples of this type. In most cases of mining the drum shaft carries two drums or reels, each running loose on the shaft, but attachable to the shaft through a clutch. Each drum also has its own brake so that the operation of such a hoist requires the use of several levers. If the engine has to stand close to the shaft the rope is a so-called "flat" rope and is wound up on a narrow drum be tween lateral guides like a strap. For greater depths the rope drums or reels were mounted directly upon the engine shaft and the steam cylinders were necessarily greatly in creased. Among the illustrations is a good example of such a "first motion" hoist--a pair built by the Union Iron Works of San Francisco for the Anaconda Mining Company in 1898 as assembled before shipment. Each hoist consists of two highpressure cylinders 30 by 72 in. w ith six auxiliary handling 86 M echanical Engineering engines for controlling the reverse motion, brakes, clut ches, and disk brakes. The reversing engine and the brake engines are fitted with " differential gears" and hy draulic control cylinders as often seen in marine revers ing engines. W ith this ar rangement the pistons of the handling engines move pro portionally to the movement of the controlling lever; that is, half throw of the lever gives `half travel of the piston, and so on. The pistons are locked in place hydraulically at every posi tion. The operator's plat form and the dial indicators showing the position of the cage are clearly seen. The ropes are of the flat type, 3000 ft long, and the average ; hoisting speed was about 3000 ft per min. These were exceptionally fine engines and beautifully finished. An engraving of one of two great hoists, also built by the Union Iron Works for the Anaconda Mining :? i DOUBLE 26 IN . AND 46 X 72 IN . HOISTING EN G IN E (Anaconda Mining Co., Butte, Montana.) >; t Company, is included in the illustrations. Each hoist has two compound engines 26 and by E. D. Leavett for the deep copper mines in Michigan. 46 in. by 72-in. stroke. The high and low of each engine is These great Michigan machines, however, were not always coupled to the ends of a beam or rocker. The oscillating mo exclusively hoisting engines, but performed other functions, tion of the rocker gives one end of the connecting rod a motion such as pumping, or they served a number of shafts as a cen equivalent to the ordinary crosshead. The other end of the rod tral power station. rotates the reel shaft. The ropes are flat, Va by 8 in., 3000 ft One of the illustrations shows a remarkable hoisting engine long, and the hoisting speed is 2500 ft per min. This great designed by the late Bruno Nordberg for the Tamarack shaft engine was modeled after some very large engines designed of the Calumet and Hecla Company of Michigan. A pair of simple Corliss en g in es is mounted on an A-shaped frame at each end of the main shaft with cranks 90 deg apart. The four cylinders so mounted give a combined torque curve that approximates uniformity. There is only one rope drum, 25 ft in diameter at the center sloping to 18 ft in diameter at each conical end. The con tour of the drum is such that the unloaded d escen d in g cage approximately balances the ascending cage, .thus mak ing a well-balanced system easy to control. All control, of course, is by auxiliary steam engines. I consider this hoisting engine one of the best pieces of design of its kind th at has come within my knowledge. It may be noted in passing that some very large and well-designed hoist- February, 1936 87 ing engines are to be found in the gold fields of South Africa, some of them of English design and manufacture. " sta tio n a ry e n g in e s " In applying the steam engine to the many needs of manu facturing the beam engine of W att was, for the most part, discarded in favor of the more direct system of piston, crosshead, connecting rod, and crank. The beam was used from tim e to time for large engines, particularly for large municipal pumping engines where the motion was compara tively slow. One of the last and most spectacular appearances of th e beam was in the great Corliss engine of 1400-hp erected at th e Centennial Exposition in Philadelphia in 1776. It was thought to be a gigantic engine at the time. But for most purposes the so-called " vertical" and "horizontal" type of engine became the prevailing type. By 1850, as has been noted, it had passed through the experimental stage and most all of its elements and variations had been developed. The Corliss gear, the slide valve, the poppet valve, and the Stephen son reversing link were well known by that time and widely used. The great development of the engine came, therefore, during the last 50 years of the last century. The advent of the electric generator gave a new impetus to designers. At first the generators were belt driven but for obvious reasons this was not a satisfactory solu tion, and presently there ap peared the "high-speed" en gine, either vertical or hori zontal, with the shaft gover nor, and with the generator mounted directly on the en gine shaft:. These engines were necessarily limited in size. When larger generators were required, the Corliss en gine and other engines with detachable valve gears being limited to rotative speeds of not much more than 100 rpm, the dimensions of both en gines and generators rose to h e ro ic p ro p o r tio n s . An 8000-hp horizontal - vertical Allis-Chalmers engine of this period was designed to drive a generator more than 30 ft in external dimensions. The machine to o ls d e veloped for manufacturing these engines and generators are probably the largest that have ever been made. This was the high-water mark for the Watt engine. Near the end of the century the steam turbine began to displace it for large power units and the internal-combustion engine began to in vade the field of small power units. The future of the Watt engine is, therefore, somewhat uncertain. There are still many places where it provides an ideal power unit and in its improved form of the high-speed Corliss and the uniflow it is hoped that it may have a long lease of life and usefulness. The illus tration at the head of this paper shows a 14,000-hp uniflow engine built in 1926 by the Nordberg Manufacturing Co. to operate a rolling mill. This is evidence of the fact that there still exists a place for the reciprocating engine. T H E LOCOMOTIVE The locomotive, like all other forms of the steam engine, went through a considerable amount of experimentation. Horizontal boilers w ith vertical or inclined steam cylinders; vertical boilers w ith horizontal cylinders, and curious combinatiptis of gears and rods appear among these early experi ments. From these has evolved one general type that has, not MODERN STEAM LOCOMOTIVE (Built in 1935 for the Chesapeake and Ohio Ry. Co., by the Lima Locomotive Works. The tractive power is 66,960 lb with the main cylinders and 81,034 lb with the booster. The average weight of the total engine is 477,000 lb and of the loaded tender 381,700 lb. The wheelbase of the engine and tender is 98 ft 5'A in. Steam at a pressure of 250 lb per sq in. is generated from coal burned on a grate with an area of 100 sq ft.) 88 M echanical Engineering changed in principle in re cent years. It is a far cry, of course, from the Rocket, weighing perhaps two or three tons, to a great modern locomotive weighing 200 or 300 tons, but the two ma chines are identical in prin ciple . One wonders whether a new and more efficient ma chine might not result, if the designers of lo c o m o tiv e s could forget all about what has been done in the past. At the present the loco motive is pressed with com petition from the autobus, THE ENGINES OP THE " CLERMONT" the Diesel locomotive, and (From Thurston's "History of the Steam Engine.'') the electric locomotive. Un doubtedly, all of these will find a place in our transporta accompanying illustrations give some idea of the giant size tion system, but the steam locomotive will probably hold its of some of these modern steam generators and makes one place in the field for a long time. It is to be hoped that it will wonder what the limit may be. if for no other reason than its majestic appearance and as a thriller of adventurous boys. THE MARINE ENGINE THE BOILER . No account of the steam engine can be separated from that of the steam boiler. Space forbids anything beyond the briefest comparisons. W att's engines operated on pressures only a few pounds above the atmosphere. Today, a steam pressure of 500 lb per sq in. is common and 1200 pounds is not considered extraordinary. Among the milestones of this progress may be mentioned the internally fired Scotch boiler, so long the mainstay of marine power, and the water-tube boiler which made possible the high pressures noted. The The problem of applying the steam engine to marine propul sion attracted engineers from the very first and much argument still persists as to who among these early inventors is justly entitled to priority of application. The preponderance of opinion in this country ascribes this distinction to Robert Fulton, whose vessel, the Clermont, was probably the first steamboat to make a voyage of any considerable length and to engage successfully in commercial work. The accompany ing illustrations show that the engine, built by Boulton and Watt, was of the " beam" type. From the experimental period the marine engine has emerged in several well-defined types, each suited to the work to which it has been applied. The beam as used by Watt has been applied w ith great success to paddle-wheel steamers on inland waters. The long cylinder permits good expansion, and such engines are smooth-running and durable. The steamers City of Erie and City of Cleveland, running between Buffalo and Cleveland, are driven by compound beam engines which must give high economy. Perhaps no other type of engine gives one the impression of such great power. The upward thrust of the piston rod, the rise and fall of the crosshead, the reach of the long connecting rod, and the great crankpin swinging through its orbit convey an idea of giant strength th at fasci nates the imagination. The illustrations show an inverted beam engine used in various forms when it was necessary or desirable to get the machinery below decks as in gun boats. This type of engine had great vogue as long as paddle wheels were in use in ocean service. There were, of course, other types in use. The Savannah, first ship to make the transatlantic trip, was driven by an inclined engine 40 in. in diameter With a 72-in. stroke. The Savannah was a full-rigged ship and part of the passage was made under sail. i The advent of the propeller, like the dynamo, at once called for higher rotative speeds. This problem was solved by the introduction, about 1860, of the compound engine, so-called, and the forerunner of the triple-expansion and quadruple-expan sion engines of later days. The introduction of the compound engine in marine work was in large measure the work of John A'. Y . Museum of Jrtenie and Industry Elder, who died in 1869, a brilliant engineer far in advance of his time. m o d e l o f s t e p h e n s o n 's " r o c k e t " The multiple-cylinder marine engine has been applied as a :e c 1it y >f t ;t d , r- I' d TWO OP THE FOUR 20, 000-H P QUADRUPLE-EXPANSION ENGINES OP THE "KAISER WILHELM I I " vertical engine, as a horizontal engine, and as an inclined engine. It is rarely seen today in its horizontal form. The horizontal inclined engine is still used in large inland-water ships. The Seeandbee, largest ship in inland waters, plying the Great Lakes, is propelled by side wheels driven by an in clined engine w ith a high-pressure cylinder 66 by 108 in. and two low-pressure cylinders 96 by 108 in. developing 12,000 hp. Mention should also be made of the long-stroke simple engines developed on our western rivers to drive side wheels or stern wheels for shallow waters. These direct-connected engines are peculiarly American in origin and the valve gears are also peculiar to this service. Space does not permit further description of them. The highest development of the marine engine is to be found 1 i 1 i 90 in the multiple-cylinder vertical engines using triple or quadruple expansion. Some of these engines attained great size as shown by the illustration of two of the engines of the Kaiser Wilhelm I I which developed 20,000 hp, and as can be seen it was a ponderous affair. The vibration inherent w ith the vertical recipro cation of the great pistons, piston rods, and connecting rods was often a serious problem in design and is one of the principal advant ages of the turbine for marine work. Nevertheless, a four-cylinder, triple-ex pansion, vertical marine engine, th at is, one w ith twp low-pressure cylinders, is the type of steam engine above all others to which an en gineer will give his heart away. This form permits of excellent running balance and when equipped w ith Stephenson links and tail rods is a joy to the eye and music to the ear of a man who loves engines. It is Jamie W att's engine at its very best. M echanical Engineering w a t t ' s INFLUENCE STILL PELT Last summer I journeyed from Montreal to Quebec on a steamer driven by two such en gines. I naturally gravitate to the engine room of a ship and as I was prowling around on the upper grating the French engineer waved me down to the operating platform. His En- THE SIDE-LEVER M ARINE EN G IN E OP 1849 (From Thurston's "History of the Steam Engine.") AN EARLY BEAM ENGINE FOR MARINE W ORK W ITH WOODEN FRAME (From Thurston's "History of the Steam Engine.'') glish was very imperfect and my French is zero but I did not have to understand his words for I recognized at once that here was a French " MeAndrew" trying to tell me w hat the Scotch McAndrew told Kipling many years ago when he prayed for another Burns-- To match wi' Scotia's noblest speech yon orchestra sublime Whaurto--uplifted like the Just--the tail-rods mark the time. The crank-throws give the double-bass, the feed-pump sobs an' heaves, An' now the main eccentrics start their quarrel on the sheaves: Her time, her own appointed time, the rocking link-head bides, Till--hear that note?--the rod's return whings glimmerin' through the guides. They're all awa! True beat, full power, the clangin' chorus goes Clear to the tunnel where they sit, my purrin' dynamoes. Interdependence absolute, foreseen, ordained, decreed, To work, Ye'll note, at any tilt an' every rate o' speed. Fra skylight-lift to furnace-bars, backed, bolted, braced an' stayed, An' singin' like the Mornin' Stars for joy that they are made. The nineteenth century was the century of Watt, Boulton, Stephenson, Elder, and their many associates and co workers. The twentieth century promises to belong to Parsons, Diesel, and the host of able men who have developed the turbine, the internal-combustion engine, and electrical transmission. Yet it does not seem possible that the engine of Watt w ill pass from view. There still are and probably always will be many places where a moderate supply of power is required and where this ideal prime mover fills the need and I for one fervently hope this will be the case. But whatever the future holds the steam engine of the nineteenth century will be recorded in history as the greatest invention and development of all time in its effects upon the economic life of the human race and Watt will be remembered not only as an inventor but as a benefactor of all mankind. ! : ' r ; i ! MATTHEW BOULTON (From the Beechy portrait.) MATTHEW BOULTON, 1728-1809 -i By JOSEPH W. ROE . NEW YORK UNIVERSITY, NEW YORK, N. Y. FORTUNE smiled twice on James Watt. The first time was on that famous Sunday afternoon walk in the spring of 1765 on Glasgow Green, when the idea of a separate condenser came to him. As Watt himself said, " When once few years the engine had both literally and figuratively come to a standstill. To support himself he became a civil engineer and surveyor, worked on plans for the Port of Glasgow, de signed bridges, and surveyed the Caledonian and other canals; the idea of separate condensation was started, all the improve but he made only a bare living and sank deeper and deeper into ments followed as corollaries in quick succession; so that in discouragement and debt. the course of one or two days the invention was thus far Then came Boulton. Watt first met him in 1768, through : complete in my mind." This started the long series of inven Dr. Small, who himself was introduced to Boulton by Benjamin tions which mark Watt as one of the greatest of inventors. Franklin.. For several years Watt and his partner, Roebuck, . The second smile came when the famous partnership w ith tried to interest Boulton in joining them in the development M atthew Boulton began. We have only to follow W att's of the engine, but they were unsuccessful. Finally Roebuck early struggles to see what this meant to him. Watt was an became insolvent, and Boulton, who had loaned him money, instrument maker, and in a few days had made a model which took over his two-thirds ownership in the patent in discharge demonstrated the soundness of his invention, but when he of the obligation and joined Watt as a partner. tried to build an engine "in great" he met only a succession Matthew Boulton was the son of a Birmingham manufacturer of failures; he could not make it a commercial success. For of the same name. At seventeen he invented an inlaid steel nine long years he struggled on w ith uncertain and inadequate buckle which became the fashion and was a great success. backing. He patented the invention in 1769, but within a His father took him into full partnership at 21; and in 1759, An address delivered at the Bicentenary of James Watt, Lehigh University, Bethlehem, Pa, January 20, 1936, under the auspices of the University, The Franklin Institute of Pennsylvania, The North American Branch of the Newcomen Society of England, and T he A m erican Society of M echanical E n g in ee r s. Illustrations are from Smiles's "Lives of the Engineers," unless other wise noted. when he was only 31, he succeeded to the entire business at his father's death. Under Matthew Boulton's management the business grew rapidly and the plant was moved from the city to Soho, then only bare fields, two miles north of the town. Here was built one of the first real factories, a long, three-story building, 4 $ February, 1936 81 which was added to repeatedly until it housed more than a One of the difficulties which had dogged Watt all along was thousand workers. It was the most highly developed manu " villainous bad workmanship," particularly in the boring of his facturing plant in England, and that probably meant the whole steam cylinders. Smeaton, the foremost engineer of the time, world. It' became one of the show places in England, with an had reported to the Society of Engineers regarding W att's engine influence not unlike that of the Colt Armory later at Hartford, that it was correct in principle but that neither the tools nor or the Ford plant today. Here Boulton made all kinds of the workmen existed that could manufacture so complex a artistic hardware and metalwork. Distinguished people from machine with sufficient precision. We can realize what it all over Europe, from the Empress Catherine and the Queen meant to build engines before the day of machine tools when of England down, visited it. The business rose in four years we read that Watt had been trying to work with cylinders from 7000 to 30,000 a year. Boulton made systematic and three-eighths of an inch out of round. The ingenious parallel extensive use of machinery, division of labor, and many of the motion which he invented later was necessary because there elements of modern scientific management, such as piecework, were no planers in existence even then, or for many years there a profit-sharing bonus system, and a mutual-benefit insurance after. Even at Soho things were not much better, but in 1775 society. i Boulton wrote to W att that they were out of their troubles, as BOULTON AN EXTRAORDINARY BUSINESS MAN AND MANUFACTURER Mr. Wilkinson had bored several cylinders "almost without error. " One, 57 in. in diameter, was " true within the thickness of an old shilling." Matthew Boulton was an amazing man, courageous, almost This John Wilkinson is an interesting figure. Except for his unerring in judgment, w ith tremendous vitality of mind and tremendous energy and great business ability', he was the body, buoyant and generous. He was more than a man of antithesis of Boulton and fat from lovable. He was dour, business; he was a man of culture and an intimate friend of hard, and none too scrupulous, but Boulton and Watt worked the foremost people of his generation. He had marvelous tact in close relationship with him for many years. Only Boulton in every relationship. He could meet kings w ith square could or would have put up vvith him. He designed and built shouldered self-respect but unerring courtesy, or deal with the first modern machine tool for heavy metal work, built the drunken workmen w ith patience and understanding and get first iron bridge, the first iron boat, and ordered and installed the very best out of them, where W att threw up his hands in for his forge the first steam engine built at Soho. Within a despair. He had ample capital, wide business contacts, and few years he had four such engines at work in the same plant, tireless energy. As Smiles says, " Had W att searched Europe with license "to erect one at Wilton House, as well as a devil through, he could not have found a man better fitted than to be erected where he pleases." Apparently, raising the devil Matthew Boulton was for bringing his invention fairly before is no new thing! the world." This was the man whom fortune linked to Watt, who was BOULTON A M AN OF VISION AND RESOURCEFULNESS poor, who hated business, who was timid, easily discouraged, From the start, Boulton had the rotary steam engine in and half an invalid, but who was an inventive genius of highest mind, but the first demand for the Watt engines came from the order. Could there have been a more marvelous combination? tin mines in Cornwall, which were being drowned out, as the The partnership papers were not elaborate and were prac Newcomen engines were no longer able to cope with the water tically a copy of a letter of Watt to Boulton on July 5, 1775. economically. The new Watt engines could do the work on By these Boulton was to have a two-thirds interest, pay the about one-quarter of the fuel, but Boulton and Watt had the legal expenses outstanding, advance stock in trade, and keep greatest difficulty in getting this fact accepted. The first the books. W att was to have a one-third interest arid was to engines, therefore, were sold on a: royalty basis, under which make the drawings and provide supervision. The partnership Boulton and Watt supplied the materials furnished by them at was to run for 25 years from June 1, 1775- This was the term prime cost, and took their pay for the plans, supervision of covered by the Act of Parliament extending the W att patent, construction, and a license, to run during the life of the patent, and the two partners did retire from the business at the expira- representing one-third of the share of the annual savings in tiori of the patent in fuel effected. This sys 1800. It was one of the tem was ingenious, fair, most momentous part and certain to breed nerships in history. trouble. As the years Boulton, an experi went by the royalties enced manufacturer, came to be looked on as realized w hat was in a tax, to be evaded on volved in launching any possible pretext; such an enterprise and but it was many years knew thatW att's patent before the terms of sale of 1769 would be run were based wholly on ning out by the time the fixed price. engine had become a For several years Watt demonstrated success. spent most of his time His first move, there in Cornwall superin fore, was to secure, in tending erection, nurs 1775, an extension of ing "lame ducks," and the patent for 25 years getting new orders, hy the Act of Parlia most of the time so ment just referred to. utterly discouraged that Watt moved to Soho, it took all of Boulton's and work was begun. diplomacy to keep him 82 M echanical Engineering going. One of W att's letters written at this time about an un scared the Redruth parson in 1784 on his evening walk, and expectedly favorable settlement starts off w ith " Hallelujah!. W att advised Murdock to give up his foolish idea. W att had Hallelujee!" and ends w ith the postscript " Please burn this included the idea of a locomotive engine in his patent in 1784 nonsense," and is referred to by one -of his biographers as but never took any steps to put it into execution. the only sanguine letter he ever wrote. Probably a dozen men were experimenting with the use of W att was a voluminous correspondent and for the sake of steam for navigation before 1800. In 1801 Symington was record he wrote all his letters in duplicate. Irked by the running the steam-propelled Charlotte Dundas on the Clyde. drudgery of this, he invented Fulton saw it, rode on it the letter press in common that year, and in 1803 ordered use in every office for a cen an engine from Boulton and tury. Eved down to the days W att, which was shipped to of typewriting, the old screw New York in 1805 and was copying press was as com the one which drove the Cler mon as the big leather-bound mont on its historic trip in ledgers and th e pigeon-hole 1807. As late as 1812, Watt, desk. W att would have used writing of the Clermont, de the idea only for his own con scribes its machinery and venience, w ith no realization says, "A machine of this kind of its economic value, but could not pass bridges and Boulton immediately saw its locks, which all our naviga possibilities. It was patented tions are full of; but might in 1780 and Boulton built 500 navigate in the tideway or presses, went up to London, the Thames or Severn. . . . On started in w ith the King, the whole, as far as at present and came down through the known to me, I think it House of Lords, the Com would not answer the pur mons, the bankers, and the pose you want." A strange law offices. He encountered obtuseness; and yet as far opposition and prejudice back as the 1780's he thought everywhere, but by the end of "a rotary oar," that is, a of the year 150 were sold and screw propeller. Perhaps the the device was started on its invention of the reciprocating long and useful career. The engine was glory enough for profits of this business carried one man. th engine business over some In the later years of the of its most critical days. partnership the firm came out For many years the business JAMES WATT into the sunshine of assured of Boulton and Watt was (From the Beechy portrait.) fame and prosperity. From really th at of consulting en 1775 to 1800 Boulton and gineering and the collection of licenses for the engines, w ith W att erected 289 engines in England alone, as follows: manufacturing largely incidental. They furnished the plans, supervised erection, and made and supplied the valves, valve gears, and "nozzles." Wilkinson cast and bored the cylin ders, while the foundations and walking beams were supplied Years 1775-1785 1785-1795 1795-1800 No. Total hp Avg hp 66 1238 18.7 144 2009 14.5 79 1296 16.5 by the purchaser or from local sources. There was much fric tion latent in this situation and finally in 1795 the partners 289 4543 15.7 set up their own shop and furnished all the piarts themselves. By th a t time, also, they were in a position to sell the en gines outright. It is strange that w ith all the creative genius which Watt put into the steam engine he seems to have had so little interest in its possible broader applications. W att not only made no great contribution to steam transportation, either by land or water, but he seems to have had little interest in it. It was Boulton who had persistently to prod W att to the full de velopment of the rotary engine. He saw clearly from the start that this would be its major use. Against W att's advice and urging he pushed the rotary engine and undertook These 289 engines were for the following uses: Cotton mills 84, colleries 30, foundries and forges 28, copper mines 22, canals 18, breweries 17, water works 13, woolen mills 9, and miscellaneous 68. The list does not include engines sold to other parts of the British Isles or on the Continent, but the number of these was relatively small. Including these the total horsepower represented was about 5000, or a little more. These engines were the source of the mighty river of mechanical power. Today we have single units of more than forty times the capacity of all the engines built by Boulton and Watt during their entire partnership. to carry himself the risks involved. When the problem was satisfactorily solved W att was anything but elated over it, and BOULTON AND WATT PARTNERSHIP CARRIED ON BY SONS he doubted for some time "whether it would be worth the With the expiration of the patent the two partners re while of the Soho firm to accept orders for engines of this sort." tired and the business was taken over by Matthew Robinson It was Boulton's energy and vision which not only guided the Boulton and James W att, Jr. The two sons handled the busi fortunes of the firm, but developed the economic possibilities ness wisely. They developed the enlarged manufacturing of the steam engine. It was Murdock, his workman, who business begun in 1795, met the problems arising from the expi made the first steam self-propelled model in England, which ration of the patent and termination of royalties, and re- February, 1936 83 organized the whole enterprise there be than this, written by Watt to meet the new him self, dated competitive condi Glasgow, 1809, and tions. Erich Roll found among the has written a book1 Soho papers? in which he says that the career of Boulton and Watt in its'second phase under the sons was Through the whole of this business Mr. Boulton's active and sanguine disposition served to counter in many ways as re balance the despond markable as it had ency and diffidence been in the ' pre which were natural vious generation. SKETCH OF WILKINSON' S BORING MACHINE USED FOR M ACHINING CYLINDERS OF W ATT's to me; and every as It, of course, did not contribute so much to engineer ing, but its pioneer ing work in factory organization and adm inistration ENGINE (On two oaken stringers SS, frames FF were mounted which carried a hollow boring bar A driven from the end. The cylinder to be bored was clamped to saddles as shown. The cutters were carried on a head which rotated with the bar and was fed along it by means of an internal feed-rod and rack. In the machine shown the feeding was done by a weight and lever which actuated a pinion gearing with the rack R, but later a positive feed through a train of gears operated by the main boring bar was used.) sistance which Soho or Birmingham could afford was procured. Mr. Boulton's ami able andfriendly char acter, together with his fame as an en gineer and active was an outstanding example of early industrial method. manufacturer, procured us many and very active friends in both Houses Watt lived for twenty years after his retirement, surviving of Parliament. . . . Suffice it to say, that to his generous patronage, Boulton by ten years, one of the few inventors who came into his own, in far better health than he had ever known in early life, with comfortable means and honored by all. Boulton, unlike Watt, continued his interest in the business, although out of active management, particularly in the development of coining machinery. In the last few years his health became broken and he died in 1809. Boulton was one of the great business men of all time^--one of those who, without being great inventors themselves, make inventions useful to society. They are better than amassers of wealth, they are creators of wealth. W ithout Boulton W att's engine would, of course, have ultimately come into use in some the active part he took in the management of the business, his judicious advice, and his assistance in contriving and arranging many of the applications of the steam-engine to various machines, the public are indebted for a great part of the benefits they now derive from that machine. Without him, or some similar partner (could such a one have been found), the invention could never have been carried by me to the length that it has been. Mr. Boulton was not only an ingenious mechanic, well skilled in all the arts of the Birmingham, manufacturers, but he possessed in a high degree the faculty of rendering any new invention of his own, or of others, useful to the.public, by organising and arranging the processes by which it could be carried on, as well as ofpromoting the sale by his own exertions and those of his numerous friends and cor- other way, but Watt himself would probably, like poor John respondents. His conception of the nature of any invention was Fitch, have died a broken quick, and he was not less hearted failure. ^ Boulton had a better idea of the usefulness and pos sibilities of the steam en gine than W att himself. He believed in it when Watt lost heart. ``He was W att's very backbone. He quick in perceiving the uses to which it might be ap plied, and the profits which might accrue from it. When he took any scheme in hand, he was rapid in executing it, and on those occasions spared neither trouble nor expense. He was a liberal encourager braved and risked every of merit in others, and to him thing to carry the scheme the country is indebted for through. He mortgaged his lands to the last far thing; borrowed from his personal friends; raised money by annuities; ob tained advances from bank ers; and had invested up various improvements which have been brought forward under his auspices. . . . In respect to myself, I can with great sincerity say that he was a most affectionate and steady friend and patron,with whom, during a close con ward of 40,000 in the en nexion of thirty-five years, I terprise before it began have never had any serious to pay." difference. WATT'S TRIBUTE TO BOULTON W h a t b e tte r or more authoritative tribute could The two men lie buried near each other in Handsworth Church, which is as it should be. ' There 1"An Early Experiment in Industrial Organization," by Erich Roll, Longmans, Green, and Co., New York, 1930. HANDSWORTH CHURCH, THE BURIAL PLACE OF BOULTON, WATT, AND MURDOCK can be no full acknowledg ment of the world's debt to James W att which does not include M atthew Boulton. WATT Symbol of the Industrial Age B y WILLIAM L. BATT PRESIDENT, THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS THE MATERIAL conditions under which we live todayare so commonplace to us that we are likely to forget that life has not always been so well ordered. In the abundance of our present civilization it is well for us to recall how comparatively re cently this abundance was made possible, and how our forefathers, not so far removed, lived under circumstances of a vastly different character. It was a rather rugged existence for most of them. All a man had was w hat he could pro cure w ith his own two hands un less he belonged to th at limited class of society th a t could afford to hold slaves or employ servants. Means of transportation were limited to foot, to horse, and to wind-blown ships, and life was lived in a narrow orbit. Of amusements there were few, and the day was largely occupied w ith the w ork of maintaining a bare ex istence. These conditions had ex isted for thousands of years from the beginning of recorded time. They were the conditions under which James W att was born and lived. W hat an extraordinary change has taken place in the short space of time since the birth of Watt. Today we live in comfort and ease; we are surrounded by possessions of infinite variety; and so ac customed have we become to them that w hat would have been an almost unattainable luxury for the few of a hundred and fifty years ago is a necessity for most of us today. One of the extraordinary fea tures of the modern industrial age is the fact th a t, to an amazing de- An address delivered at the Bicen tenary of Watt, Lehigh University, Bethlehem,Pa., January 20, 1936, under the auspices of the University, The Franklin Institute of Pennsylvania, the North American Branch of The New comen Society of England, and T he A m e r ic a n So ciety o? M e c h a n ica l En g in e e r s . gree, it is the direct, traceable re sult of one man's life and work. This conclusion w ill seem fantastic to many, and so it would have seemed to me before I was obliged to study more seriously in prepa ration for this address the life and work of James W att. Had I been asked to name th at single man whose influence on the whole world was most outstanding, I suppose my mind would have searched out some such familiar character as Columbus, George Washington, Robert Fulton, Na poleon, Stephenson, or Abraham Lincoln, or, perhaps, Thomas Edison. Certainly it would never have occurred to me to select a man whose major accomplishment was the perfection of the steam engine. But now I am willing to ask whether we cannot agree, after reviewing the life of James W att, th at the influence of bis work has been of greater significance to the world than th at of any other single man in recorded history. This thesis I shall attempt to prove. We shall all doubtless agree that the industrial age which has pro duced so many miracles has been made possible largely through the availability of power in acces sible locations and at reasonable cost. Only through cheap power has man been able so enormously to multiply his own efforts, to produce more things in less time and at less cost, to move himself rapidly from place to place, and, withal, to have time left for rest and play. This economic phe nomenon has not been without its collateral problems, many of which are still unsolved. In the brief time at my disposal I shall not attem pt an appraisal of the values of this new civ ilizatio n ; I shall merely attempt to analyze its his tory and the part played by the man whose birth we are com memorating here today. If W att had done nothing more 92 M echanical Engineering than perfect the steam engine, there might still have been a great gap between his work and the dawn of the industrial era. But during his lifetime, and largely as a direct result of his inspiration, all of the essential elements of industry as we know them today were conceived and put into practice. For example, it is probable that W att did more to advance the development of the modern machine tool than is commonly acknowledged. Certain it is that up to his time there was no machine capable of boring a cylinder even reasonably round. The direct credit for the invention of the modern boring mill goes to John Wilkinson, but I think it likely that Watt had a large part in its development. Surely in W att's lifetime and to a greater or lesser extent as a result of the needs of his engine manufacture, the modern machine-tool industry had its birth. One who visited the Machine Tool Exposition at Cleveland last year and saw that impressive aggregation of machinery capable of producing parts from an ounce to many tons in weight and to interchangeable tolerances of a fraction of a ten-thousandth part of an inch, must have thrilled to man's accomplishments. And all this was developed in the short space of one hundred and fifty years. I suppose it will be obvious that standardized manufacture is a foundation stone in the economic structure of our day; and if we could agree that W att was one of the first, if not the first, who saw this as a desirable process, it would aid in establish ing my thesis v Certainly, it seems clear beyond argument that W att's proposal to build steam engines in quantity from more or less interchangeable parts and to a uniform design was revolu tionary. Before his time, all such construction was fabricated and assembled where the machines were to be used, and rarely ever were tw o parts alike. W att seems to have had a very definite appreciation of exact measurement. His trade of in strument maker logically induced the habit of precise work, and I surmise that it was this quality which made him dissatis fied w ith existing machine tools and their output. It was natu ral for him to conclude that good machine tools would have to be designed if good work were to result; and such work could only be carried out at one spot w ith adequate gages and tools and measuring equipment. So began the modern factory plan. How much of this ambitious program belonged to W att and how much to his partner, M atthew Boulton, cannot be said too exactly, but it is not too much to credit W att w ith a substantial part in these first beginnings of standardized manufacture. W att's name is not directly associated w ith the first successful locomotive, but there seems to be no doubt th at he had given the matter much thought and was responsible in considerable part for the road engine built by Richard Trevithick in 1804. There were no principles in that machine or in those soon to follow that W att had not fully developed, and it is probable that it was only the press of his other work th at kept him from constructing a workable locomotive. I have "seen no evidence that W att had any definite contact w ith the building of the steamship, but Robert Fulton's Cler mont was equipped w ith one of his engines. Thus the steam boat may fairly be considered, in some measure at least, as his contribution. And so I think you will agree that it is not fantastic to con tend that from the one man, James W att, have come more or less directly cheap power, interchangeable manufacture, the modern machine tool, and long-distance transportation--the very foundation stones of the industrial age. Now behind such extraordinary contributions to the arts of peace there must have stood an extraordinary man, and James Watt was all of that. It seems clear to me th at he had certain well-defined characteristics which were responsible for his success, and that we shall find something in a study of these characteristics that may be of value to all of us. To th e young man in college or at the threshold of business life, W a tt's handi caps as a youth and the way he surmounted them may be an inspiration. And in the older man W att's unusual relation ships with his associates may awaken a new interest in a closer cooperation with one's own associates; because it is evident that W att's friendships were preeminent in determining his success. I shall not tire you with a repetition of the biographi cal facts of W att's life--you will have heard those many times before and perhaps at length today--but I shall try to visualize the man himself as if he were, perhaps, here w ith us, working within the walls of this great institution, as he did at the Uni versity of Glasgow. There was nothing remarkable in his appearance; a rather shy person, doubtless we should call him self-conscious; his health not too good and possessing none of those swash buckling traits that made men stand out in a day of physical accomplishment. Certainly a rather moody person, given to introspection and melancholy. These are the negative traits, perhaps. The positive ones were a heritage of intelligent parents, a painstaking attention to detail, a thorough mind not satisfied w ith a job half done, and a real genius for making and holding friends. What the friends of W att did for him is of in calculable significance; but friendship is a force and cannot exist without an equal and opposite reaction. We know th at Watt gave generously of himself to his friends; it is clear also that w ithout Dr. Dick and John Anderson and Dr. Black and M at thew Boulton, not to mention many others whom history records, W att would have missed the wise advice, the inspira tion, the scientific guidance, and the business assistance so vital to success and all of which he absorbed and utilized to such an unusual degree. Without the encouragement of these friends, and particularly that of Boulton, W att would probably have died a disappointed and unsuccessful inventor, for W att was not trained in business methods, and his type of mind was not fitted to solve many of the problems that were t:o arise. The intrica cies of an astronomical instrument were as child's play to him, but the ways of finance, credit, and the usual demands on the business mind were alien ways to him. To the trusted friend M atthew Boulton, a man of unusual business ability, industrial experience, and financial resources, W att turned for advice and the partnership between these two lasted till death. I t was an unusual business partnership, so charged was it w ith friendship, loyalty, and mutual confidence; and I cannot emphasize its importance too strongly. The written and unwritten history of the past is filled with the records of men who almost succeeded in doing some remark able thing. There was John Fitch, for example, who built and operated a steamboat on the Delaware River years before the Clermont was built; but we do not associate Fitch's name w ith the first successful steamboat. Fitch died a disappointed man and Robert Fulton's name fills the pages of history as the father of the steamboat. Moreover, Richard Trevithick prob ably built the first complete steam locomotive to run on rails; but Stephenson's "Rocket" is the one we all remember. The pages of history are filled w ith similar instances where, w ith apparently the same resources, one man failed and another succeeded. While there can be no single reason for these successes and failures, man's relation to his fellow man becomes the more significant in determining his progress as the structure of society is increasingly complicated. That man who can supplement his o w n w eak n esses by th e s tr e n g th of o th e rs h as a great advantage. Here in this center of the production of iron and steel, it may be of special interest to note that Carnegie was never actually an outstanding steel man, although he made a fortune in the industry. His success came from his ability to February, 1936 93 FROM CERTIFICATE OF MEMBERSHIP IN THE INSURANCE SOCIETY OF THE SOHO MANUFACTORY OF BOULTON AND WATT (Discovered among the papers left by Watt in the garret workshop at Heathfield by George Tangye, Esq., and presented by him to Prof. John E. Sweet, who, in turn, presented it to The American Society of Mechanical Engineers. The letter from Watt to Boulton, a facsimile of the end of which is reproduced on page 94, was presented to The American Society of Mechanical Engineers by Mr. Tangye at the joint summer meeting, Birmingham, England, July, 1910.) surround himself w ith the finest brains that the steel industry could produce and to possess their loyalty and cooperation. This was the one characteristic ofJames W att which, in my ob servation, contributed most largely to his success. To an increasing extent, this industrial age is demanding co operative effort and penalizing individualism. Its very exist ence has depended upon a more or less effective interrelation between production, distribution, and consumption, and the extent to which the individual has forwarded this integrated movement has, to a growing degree, measured his reward. For society is becoming increasingly conscious of its inefficiency in the operation of this intricate mechanism that it has created for the benefit of its own comfort and well being. The spec tacle of men anxious to work but unable to find employment; of factory wheels ready to turn but w ith no work for them to do; of men starving w ith fields overflowing w ith food--these are pitifully poor results from an age that has promised so much. Men w ill not long tolerate such conditions. The his tory of out own day is increasingly marked w ith the struggles of great bodies of peoples to work out a salvation for them selves, however violent the forces to effect th at end. may be. This is not a situation newly made, indeed, one may find in the records of the English Parliament of a hundred years ago pro tests over the state of things that might appropriately be said of our own times. In its struggles to find relief our social structure has sought increased mechanization, and has been willing to pay a higher and higher premium for labor-saving devices, the tendency of which, however, is to submerge the individual and interrelate him w ith the group. Before W att's day that circle of inter dependence was small, perhaps limited to the confines of a vil lage, but in any event, small enough to have characteristics of flexibility'. In the intervening years how this circle has grown! From the village to the state, from the state to the nation, and from the nation to the entire civilized world. And in that growth, brought about almost wholly by improved transporta tion and communication, the individual has steadily tended to lose his individualism and of very necessity to merge his efforts w ith those of his fellows. Whether the results have been w orth the price or not is another question, but there is no doubt th at a new group of social problems has developed. And so there inevitably arise those attempts at correction by law, by fiat decree, and by force that are foredoomed to failure. For men cannot be made good, or wise, or kind by law or force. Those characteristics, so much more necessary today than ever before, spring from deeper sources; and while friendship, tolerance, cooperative understanding are not all sufficient in themselves they w ill go far toward the solution of the manifold human problem of this industrial age. A better understanding between employer and employee; a greater tolerance between people of differing languages and colors; a more willing friend ship of man for man wherever their paths cross--these elements are vital to the continued existence of our social structure. And now for final emphasis, I cannot fail to remark that these qualities, which seem to me to h a v e been so conspicuous in W att's success, are noticeably lacking in a part of the economic structure w ith which we here tonight are vitally concerned-- the lack of unity in our own profession. Engineers have a cer tain quality of mind that tends to make them intolerant of any deviation from their conception of a right course of action and 94 M echanical Engineering are perhaps unyielding in th at give and take which is an in evitable part of cooperation. We have manifested this trait of independence in our professional organizations to the point th a t we are today overloaded w ith societies purporting to repre sent the engineer. We have not sought unity and we have not achieved strength. The spectacle of scores of national societies and literally hun dreds of local bodies w ith few coordinai- ing elements and dis- tressingly little coor t/ dinative force, would not be surprising if it were that of any other profession than ours. m y But our education and training have been of another kind. It has been basic to us to em phasize ab sen ce of waste motion and sim plicity--all of those elements th a t go to make up efficiency. Indeed, most of us base our livelihoods on the practice of these principles. Have we applied them to the organization of our own profession? I fear we have not. Instead of a great united body of scientific and technical men, so organized as to appraise its social and economic responsibilities and to present united and determined front, we seem only interestedin our own little corners and the narrower confines of our own local interests. If an effective degree of professional unity is to be achieved, some sacrifice will be involved; but w hat a vi sion there is of the possibilities that may flow from such a union. Is it too much to conclude that the very life of the industrial age and of our present organized society may hang in the bal ance? Unity of the engineering profession can be achieved if the leaders of the scores of national so cieties and hundreds of local societies, sup ported by the tens of thousands who com prise their member ship, will set as their single .guide th e se c h a r a c te r is tic s of friendship, tolerance, and cooperative under standing--these self sam e characteristics that sto o d o u t in strong relief in James W att'slife, th at bound him to th at extraordinary circle of friends of which we have heard so much today and without which his inventive mind and mechanical genius might well have gone for naught. W ithout these qualities of mind and heart in this industrial age of W att's creation--in this profession which has had so sig nificant a part in its growth--it and we may go as other futile civilizations of the past and their peoples have gone. i; H EATHFIELD, WATT S HOUSE AT H A N D SW O K H HEATH, BIRMINGHAM , W HERE HE SPENT THE LAST YEARS OP HIS LIFE (From Smiles's "Lives of Engineers.") ds P- , oi (>* n- f :r- : :ir J sc i of :e, 1 i^Jff CS in cs id I ve id it. aJ g:ic J Ii? PROGRESS * POWER-- A Review By CHARLES E. LUCRE COLUMBIA UNIVERSITY REVIEW of progress in power is consciously or un consciously guided by some conception of what consti tutes progress, and by w hat standards it is to be judged in dealing w ith the fact data of the 1935 reports of the several professional divisions of The American Society of Mechanical Engineers. TJiese reports are devoted to new engineering de velopments, and improvements in generating equipment or in operating procedure are recorded and discussed. A summary of these developments is usually accepted as a review of progress in power on the assumption that power progress is the same thing as engineering development. However, there seems to be some advantage in the unconventional hypothesis that how ever necessary engineering development may be to progress in power, these things are not identical, and the former does not always mature into the latter. Whatever may be the meaning of progress, it is clear that a review should be something more than a statistical statement. It should have some elements of judicial opinion. An editorial differs from a reporter's story in the daily papers. OBJECTIVE o r PROGRESS IN POW ER IS REDUCTION IN POWER COST OR IMPROVEMENT IN SUITABILITY OP PLANT The true objective of progress in power is reduction of power cost, or improvement of suitability of generating plant for a special case or class of drive in any of the divisions of trans portation or stationary service. Whatever has reduced power cost is thus proved to be an item or a means of power progress, and the same is true of anything that improves the suitability of equipment for a given service w ithout increase of power cost beyond what can be borne. There can be no absolute measure of progress. Comparison of new w ith old on a com petitive basis as to power cost and service suitability must de termine when progress has been made. Those new engineering ideas or inventions, newly developed processes or equipment that are the result of a power-progress motive, may or may not finally be entitled to such a claim. The conclusion must be deferred until after acceptance and use in competition with alternates. Progress certainly is not measured by novelty alone, whether engineering progress or power progress. While conclusion must thus be deferred, there is value in a weighing of possibilities of engineering improvements as prospective means of making progress in power. This sort of thing is, moreover, quite necessary in the formulation of plans, programs, and policies by engineers and organization execu tives concerned w ith any phase of power activity. Usually each one prefers his own opinion, and there is just as touch competition between opinions as there is between alternate power-generating systems and equipment. Interpretation of facts to discover trends may be as important as the facts themselves, and it may indicate directions worthy of effort in the interest of progress, or, negatively, directions in which no effort seems worth while. Identification of Based on the: 1935 Progress Reports of the A.S.M.E. Divisions on Fuels and Steam Power, Oil and Gas Power, and Hydraulics; the Edison Electric Institute Prime Movers Committee; and the Association of Edison Electric Illuminating Companies' Power Generation Committee. Presented at the Annual Meeting, New York, N. Y., Dec. 2-6, 1935, f The A m e r ic a n Society or M ech a n ica l E n g in e e r s . trends really amounts to forecasting, dangerous but necessary, and it requires information on both tangible things and in tangibles, the interpretation of which may lead to conclusions as to what should or should not be done w ith no specific evi dence in that direction. THREE MAJOR TYPES OP PERSONS CONCERNED W ITH POWER PROGRESS There are three major types of persons concerned w ith power progress and each may properly set up different standards of judgment as to advances in its own zone of activity: (1) The power user and engineer of utilization or application of power; (2) the manufacturer of power-generating equipment, and the designing engineer; and (3) the operator of power equipment and the operating engineer, independent of power use and of creation of means of power generation. The power user must be put in first place as the supreme court of judgment of com petitive cost of power and of the suitability for his purpose of alternative means of generation, the supplying of which is the business of the other two groups. The other two groups whose attention is necessarily con centrated on alternative means of generation must deal with sources of energy, efficiency o f transformation, apparatus de sign, and performance limits, but here novelties that are engi neering improvements worthy of notice as items of engineering development may not be classed as real contributions to power progress until accepted by the first group, the user, as com petitively better for his purposes than what had been avail able. Admiration for the ingenuity of the designer or in ventor, for the profundity of knowledge of the research engi neer, or for the resourcefulness of the solver of technologi cal problems is apt to obscure the fact that the result is accept able and salable to the user only when the new generating equipment produces cheaper power, or is more suitable for his needs. While the user group is the one that must pass judgment on progress as to competitively acceptable improvements in generating equipment, the exercise of this judgment by one class of user has been too often limited by disinclination to change an old practice, thus minimizing the prospective value of new means perhaps developed and in successful use by another class of user, and so close the door to possible progress arising from the efforts of the other two groups concerned with the improvements of means. Open-mindedness on the part of user groups is a prerequisite which is essential to all power progress. There is evidence of progress by all three groups, both tangi ble and intangible, the tangible being concerned w ith creation of improvements in new equipment, in operation of equipment, and in user acceptances, especially as between different groups of users, such, for example, as stationary in relation to trans portation classes of users. Some observations and comments on progress are given in w hat follows in four classes, the first being general as to systems of generation, and the last three based on the steam, internal-combustion, and hydro systems, respectively. Some are items of power progress, others of engi neering development, and each reader may judge for himself the relation of the latter to the former. 95 96 M echanical Engineering GENERAL FACTORS IN POW ER PROGRESS Intangible progress is evidenced by rapidly growing ac ceptance by all three groups of research, properly defined and properly directed, as a necessary activity instead of something to be suppressed as a nonproductive expense. This was men tioned last year1w ith reference to means of generation, but it is being extended to the user problem of selection or adoption of alternate driving equipment. The key to this problem is ration alism of analysis of relations between cause and effect, as distinguished from empiricism or tradition, and rational analysis has never been so actively accelerating in so many directions as now. In fuel-burning systems the extent to which premium prices for special grades of fuel and the corresponding increase of fuel expense per horsepower-hour may be justified by increased suitability is receiving more attention and new answers are to be expected. Should fuel be processed w ith cost addition to suit burning equipment, as, for example, in the gasoline en gine? Should higher-priced fuels be selected from grades avail able but not equally suitable, as, for example, coal for a given stoker? Or on the other hand, should burning equipment be designed to be more independent of fuel grades and kinds, both in internal-combustion engines and in steam boilers? Which practice will best promote progress? The proper degree of operating reliability in relation to life, and to life per unit of capacity per dollar of investment for generating equipment, is an old question that has been differ ently answered for transportation motive power especially w ith internal-combustion engines, compared w ith stationary service in Units of various sizes. It needs further study and clarification. Increase in reliability in fuel-burning systems has been an objective and its attainment in many directions a more notable mark of progress than increased efficiency. It contributes both to increased suitability or serviceability and to reduction of power cost in transportation motive power and stationary power plants using either steam or internal-combustion systems. In aircraft engines an operating period of 500 hours without overhaul is now commoner than one of 50 hours at the end of the War, and in automobile engines the foolproofness th at has be come standard and permits of an operating life in unskilled hands of about 1000 hours w ithout overhaul, is a real achievement. In central-station practice where the most highly skilled operators are the rule, reliability reduces power cost through reduction of expense of outage or its equivalent fixed charges for spares, in addition to other items, and considering what the boiler must do, the following quotation from the recent report of the 1935 Prime Movers Committee of the Edison Electrical Institute is evidence of true progress: "Boiler avail ability for high-pressure units compares favorably w ith, or exceeds, the turbine availability," and the availability factor is 90 per cent more or less. STEAM DEVELOPMENTS Coal is the most abundant fuel and always will be, so its utilization to the maximum degree is a m atter of importance in the interest of reduction of coal expense per horsepower-hour w ith growth of power production, and coal-burning furnaces w ith increased independence of rank or grade of coal would contribute to power progress. Equally so is the furnace that can burn alternate fuels, oil, gas, or coal, w ith the least change in structure, reliability, and efficiency of absorption of heat, when and where heat in one of these forms may be cheapest. The universal fuel furnace is truly a power-progress objective. 1See "Progress in Power," by C. F. Hirshfeld, M echanical E n g i n e e r in g , February, 1935, pp. 99-102. Greater reduction of fuel expense per horsepower-hour is possible in this direction than by increased efficiency of plant. This is a phase of reduction of premium prices for fuel, but also one of improved operating reliability through increased in dependence of grades or kinds. At the present time, develop ment in pulverized-coal furnaces, which are suitable for a variety of grades of coal, and for gas or oil, is the most promis ing line of attack. The successful use of high pressures and temperatures in stationary practice, the figures for which are the same as last year, 1400 lb at 850 F w ith reheat, or 600-800 lb at 800-900 F without reheat, except for 1400 lb at 900-950 F, is beginning to affect marine practice, an especially conservative section of the user group. This is an interesting observation in view of the fact that ships have been the laboratory for the development of Diesel engines. Some American steam vessels are now operat ing w ith 450 lb and 750 F and some foreign ships at 600 lb and 850 F, but current American proposals reported last month by William W. Smith, chief engineer of the Federal Ship Building &Dry Dock Co., Kearny, N .J., to the Society of Naval Archi tects and Marine Engineers are in line with stationary practice of 1200 lb at 950 F. The dominance of steam in large capacities with turbines, and the successful competition of Diesel engines in small capacities burning premium-priced fuels, noted last year, are concentrating more attention on the reasons for the situation and the possibilities of changing it. High efficiency, necessary for a competitive fuel expense, imposes high steam pressures on the small steam plant for a high cyclic efficiency, but the turbine has been unable to utilize it efficiently in small units. Does this mean that turbines never can succeed here? Does it mean that the reciprocating engine may be revived for this service? If so, the multicylinder, balanced, high-speed gasoline engine is a model of mechanism that could be easily adapted to double-acting steam cylinders. There is no difficulty in producing suitable boilers. Progress in this direction, now definitely problematical, has as a motive the removal of existing fuel limitations as to kind and price from power-generating units of small capacity, equally suitable for stationary service and for transportation motive power, especially for locomotives and small ships. Lack of improvement in maximum efficiency of steam-power generation in the interest of reduction of fuel expense per horse power-hour or kilowatthour provides a motive for effort to correct the condition, and success in this direction would be real progress. The near approach to what seems to be the limiting efficiency for steam, w ithout increase of other items of power expense or loss of service suitability, is responsible for an effort to find new chemical compounds of proper physical properties for power cycles of a single fluid, or with several fluids cooperatively. The mercury-steam installations at Kearny and Schenectady as examples of dual vapor cycles in series are noteworthy examples of increased efficiency. Bring ing these to the state of satisfactory operativeness has meant the solution of innumerable engineering problems, many with no precedent, and is a noteworthy development that stimulates interest in future reports on the effect on power progress. Chemical efforts to produce new and satisfactory working vapors are to be encouraged, especially in view of success at tained in development of new refrigerants of desired properties. Thermodynamic study of multiple cycles is also worth while, particularly w ith the objective of finding regenerative cycles of two or more working fluids th at may approach most nearly the ideal condition of constant-temperature addition of all input heat, and constant-temperature abstraction of all heat necessary to close the cycle, and correcting the inefficiency February, 1936 97 effect on cycles of temperature changes w ith heat content of the working fluid. Much progress in steam-power generation is to be expected n another direction, th at of raising the efficiency and reducing the fuel expense of those units that have less than the maximum attainable efficiency of the system. Development of ways and means of solving this problem of economic modernization of old equipment, or of its disposal and replacement, has been in tensified by the depression, and results of great value are to be expected. Progress in steam power in central stations is more evidenced by rational analysis of possibilities and programs of execution when additional capacity is needed, than by actual tangible progress, but .this result seems to be just around the corner. The planning for most economical ways of additing capacity has for one of its objectives the best means of salvaging or replacing old, obsolete equipment as applied to the individual station and to a system of several stations as a whole. Super position of new high-pressure units on old low-pressure units is one possibility that looks promising. The distinction be tween interstate and intrastate system operation, resulting from recent government action, is a new factor in th is study of how to make progress in central-station generation when the time for action arrives. From the reference reports of the A.S.M.E. Fuels and Steam Power Divisions for 1935, some items have been abstracted. These are all engineering developments and their relation to power progress is open to interpretation by any one: Lack of new installations, no outstanding developments, concen tration of effort on improved operation and solution of many detailed problems. Improved equipment availability factors, especially for high pressures in central stations and warranting unit arrangements of highpressure boilers and turbines. Modernizing programs in both central stations and industrial plants. In boilers: Extension of waterwall practice to underfeed stokers; continued trend toward pulverized coal and toward unit system; more flexibility and wider range of pulverizedcoal burners; slag screens in pulverized-coal furnaces; keeping tube bank clean; cinder, dust, and fly-ash control; increased use of stokers in small capacities under 1200 lb per hr and increased use of sprinkler type; treated feedwater in place of condensate; control of superheat, especially after a change of fuel; remodeling of furnaces to increase dependability and increase capacity; determination of circulation limits of high-level water tubes and correction for overheating zones; steam washing to reduce superheater and turbine deposits; continued use of drumless boilers abroad and study of competitive situations here. Pipe-joint welding increasing and stress relieving of metal; special metals. Turbines: Perfection of details; better materials; casing growth; blade corrosion; erosion and inspection; special oils and oil treatment; high-speed proposals for large units. Condensers in general unchanged; tube materials; slime control. Pumps: Improved pack ing, bearings, and supports. INTERNAL-COMBUSTION DEVELOPMENTS Gasoline-engine practice in powering automotive vehicles, while proceeding steadily w ithout revolutionary changes, is, nevertheless, making progress that should have reactions in other directions. 0 0 The practicability and utility of reliable balanced high speed reciprocating units of good torque characteristics is a demonstrated fact, and the adoption of similar mechanism for high-pressure steam engines is feasible, if it is found th at they are found to be economically justified. ( 0 The large production volume of identical small units with modern shop tools and methods has proved th at power generating capacity can be produced at a low cost in this way. The new Ford V-8, 90-hp engine at 3800 rpm peak weighs fO lb and retails at $135, or $1.50 per hp at the peak, and *0-27 per j|-> The production of automobiles and trucks for 1935 is expected to be four million-, and the horsepower capacity can be estimated by any one. Adoption of this system is now being extended to Diesel engines, primarily for tractors, and it is making cheap units available for isolated-plant stationary service and for other transportation motive power but with limited life. (c) Low cost of power-generating capacity permits a cor respondingly low total life without increase of, and perhaps w ith decrease of, fixed charges per horsepower-hour, reduces the problems of disposal of obsolete equipment, and encourages new development for replacement, especially as elapsed time and operating-life period approach equality by continuous use. Interurban truck operation of nearly 24 hr per day is an illus tration of the latter point. This general practice of producing cheap capacity of short life prompts inquiries as to the proper relation of it to the opposite one typical of large stationary stations, of building equipment for long life, 20 to 40 years, at a higher cost per unit of capacity, even for equal fixed charges, balancing cost of capacity against life. Gasoline-engine performance has reached its peak in the radial air-cooled aircraft engine, of which the Wright " Cy clone" is an example of the largest size and maximum capacity per cylinder, securing 166.6 brake mep at 1950 rpm with super charging in nine cylinders, 6l/a in. by 67/s in-, or 83.4 hp per cylinder. This is a total of 750 hp, w ith a gasoline consumption of 0.60 and 0.48 lb per hp-hr w ith and w ithout supercharger, respectively, and a total weight of 1000 lb, or 1.31 lb per bhp and 0.53 lb per cu in. of displacement. Substitution of fuel oil for gasoline, the Diesel engine replac ing the gasoline engine as transportation motive power is an example of reduction of premium prices for fuels processed to fit an engine, by changing the engine from the carburetor to the injection mode of utilization to fit the cheaper fuel, but it is threatened w ith loss of advantage by excessively detailed specification of grades of fuel oil. This again invites attention to the desirability of a liquid-fuel engine of such design as will be independent of grade of fuel, or as much so as possible to insure maximum suitability and minimum fuel expense in power generation. The motive-power cost competition between motor ships and steamers continues, but the situation seems to be clearing up. While European practice still favors motor ships of larger size than American, both agreeing in adopting steam for the highest capacities, the European trend toward larger Diesel engines, 20,000 hp more or less, is not so marked as it was, as marine steam-plant efficiency is being raised. For ships re quiring 2000 hp or less, Diesel power is in general cheaper than steam, and the competitive range of sizes now lies, interna tionally, somewhere between 2000 and 15,000 hp, with a lower maximum here, and with some exceptions at both ends. The adoption of Diesel motive power on rails, especially for locomotives in competition w ith steam, continues, and has stimulated development of new designs. The relative com petitive merit of the two types as to service, suitability, and power cost will not be known until the end of the period of evolution. From the reference report of the A.S.M.E. Oil and Gas Power Division, for 1935, some items have been selected, as possible contributions to progress in power to be judged by appropriate standards: Increased use of high-speed automotive-type Diesels in trucks re placing gasoline, more than 2000 in use and five manufacturers; growing demand for similar units for boats under 50 ft. Three new manufac turers' designs of submarine engine developed--Winton, FairbanksMorse, and Hooven, Owens & Rentchler, same for rail cars and locomo tives, with others by McIntosh and Seymour and Ingersoll-Rand; the i 98 M echanical En g in eer in g ; use of the opposed-piston engine in submarines and rail cars; the BuschSulzer V-type locomotive engine; the 3600-hp Winton locomotive en gine for the Santa Fe. Trend toward high-speed engines for marine service; high efficiency of Sulzer engines in the M.S. Dorset and Durham, 0.35 lb oil per hr per shaft horsepower for all purposes; use of exhauststeam boilers on ships. New Diesel manufacturing plants of AtlasImperial, at Matoon, 111., Hill, at Lansing, Mich., and Worthington, at Buffalo, N. Y. Production for 1935 estimated at twice that for Perhaps as important as turbine improvement is th e effect * of the use of methods employed in perfecting turbines on the J development of pumps utilizing similar hydraulic principles | but required to meet a wider range of conditions o f head speed, capacity, and temperature w ith all sorts o f liquids, including dirty ones carrying solids in suspension. T his is, of course, not direct power progress, but an engineering develop 1934, from 3/< to H/j million horsepower. ment growing out of former hydro-power progress. I t is ap plicable to progress in the power-consuming field, b u t also HYDRO-POWER DEVELOPMENTS applicable to power progress as pumps are used as auxiliaries Characterized by w hat is probably a higher cost of potential energy in form available for use in the prime mover than for any fuel-burning system, owing to fixed charges on water concentrating and protective works, by irregularities in supply, fixed location w ithout reference to markets, and as near to 100 per cent efficiency of utilization as man may expect to reach, it is surprising that the unique difficulties in making progress in steam-power plants. Especially interesting is the report that the efficiency of some centrifugal pumps has been brought above 90 per cent, in line with that of turbines, considered, only a few years ago, to be an impossibility. The reference report of the A.S.M.E. Hydraulic D ivision for 1935, notes the following items of development: in hydro power are not better understood, especially with the Large sizes of Frances turbine, 100,000 hp at 123 ft for River Dnieper, constant strengthening of competitive generation of power by Russia; 115,000-hp at 420-590 ft for Boulder Dam; and propeller tur '.6 Diesel or steam units located at the power market or point of bines of 45,000 hp at Wheeler Dam. Centrifugal pump lifting water use, to which point the hydro power must be electrically trans part time, for turbines proposed for Passamaquoddy along lines used at !H. mitted. Rocky River station, Connecticut. Centrifugal-pump design research ;jvv In spite of these limitations, w ith the possibility of. local at California Institute of Technology, associated with specifications for generation by Diesel engines in small capacities, or by steam pumps of supply pipe line across the State of California in five stations plants for larger capacities at power costs competitive w ith, with fifteen pumps of 200 cfs each, and 146 to 444-ft head, totaling 600 or lower than, transmitted hydroelectric power, hydraulic- cGfsranagdaiCnosut le1e63o4f-ft16h,e0a0d0 acfnsd craepqauciirtiyngag1a3i7n,s5t0029h0p-ftdrhievaed. . PRumatpiosnaalt power-plant construction proceeds. It is significant that these analyses with experimental data of cavitation limits; and reduction of are mainly government projects. As fuel-power progress entrance acceleration at pump entrance, leading to more reliable pump-. proceeds, hydro should recede. ing of liquids at saturation temperature, and liquids with gases, with Hydraulic turbines at their best have not been made more some application to steam-power plant service. efficient than they were. It is hard to see how they could ever be more efficient, since all hydraulic and mechanical losses CONCLUSION are but little more than 5 per cent. Moreover, they are no In conclusion, progress in power may be expected in pro cheaper except as larger size may reduce cost per horsepower, portion as engineering developments of ways and means arc nor more serviceable as to reliability or other operating features effectively prosecuted. The advance of engineering itself, except perhaps in some minor m a tte r.. Engineering develop being what it is, the future of power progress is very bright, ments applied or applicable to them have made it practicable and will remain so as long as the efforts of the engineer arc to build larger ones th at could have been produced before, properly supported and are not neutralized by influences beyond : but hardly better ones. his control. Cu#Mn0 ! formation and Growth of SUGAR CRYSTALS in VACUUM PANS B y ALFRED L. WEBRE UNTIED STATES PIPE AND FOUNDRY COMPANY, BURLINGTON, N. J. IN A NUMBER of bulletins descriptive of the research and development work done by us on calandria vacuum pans, the subject of the formation and growth of sugar crystals has been mentioned many times. During these investigations, certain important corollary conclusions became unavoidable, and it is the purpose of the present discussion to review the data carefully, inasmuch as they compel revisions in our con cept of the actualities of sugar crystallization. PRESENT PROCEDURE It is appropriate to summarize the generally accepted pro cedure in the elaboration of a strike of sugar. The first step is the making of the grain and its subsequent preparation. Be fore going into detail, it is wise to consider certain fundamentals bearing on the subject. UNIFORMITY OF INITIAL NUCLEI In the past, the literature has indicated the advisability of obtaining the greatest uniformity in the fine grains which are the starting points for the eventual full-grown crystals. Vari ous methods of effecting this result were given in detail. It is felt, however, th a t the significance of this feature has been somewhat exaggerated. Actually, extreme uniformity is relatively unimportant, as will be gathered from the following facts. Consider the char acteristics of any solid of regular formation, such as sugar crys tals, and observe that: When grain is actually formed in the pan it must be even finer than this fine seed. The variations of size of the individual nuclei must be appreciable, since it takes perhaps fifteen or more minutes, according to purity, to bring out the full crop. The point of importance, however, is that considerable variations of weight in the ultimate crystals, after they are full grown, in volve relatively smaller variations of linear dimensions. Thus it can be seen that a crystal weighing one-half as much as an other will have its linear dimension reduced by only 20 per cent, a variation which to the eye is relatively unimportant and substantially negligible from the standpoint of satisfactory commercial sugar. SMALL CRYSTALS GROW FASTER Since the increase of weight and volume is directly propor tional to the surface of these crystals, it follows that the smaller crystals will gain weight and volume faster than the large ones. In fact, the rate of weight and volume increment of the indi vidual crystals will be inversely proportional to their size. This extremely important fact becomes an automatic corrector of irregularity. It is our inevitable conclusion from this that excessive size variations are due not to irregularities in the size of the initial grain, but rather to the fact that during the strike new grains are formed at a time when they are neither expected nor wanted. All of this comes from the conditions prevailing in the pan during operation, which are not suitable for uniform crystal development, and hence the defective result. CO The linear dimension varies directly w ith the magnitude HOW SUGAR CRYSTALS START ofthe dimension. There are several methods of bringing about the formation of CO The surface of the solid varies w ith the square of the the initial grain nuclei, which are given briefly as follows: dimension. (1) The original technique of making grain is to " let it (3) The w eight or volume varies w ith the cube of the dimen come in." This was accomplished by concentrating a charge sion. of syrup progressively "dead end," until the supersaturation One of the principal factors controlling the rate of growth of crystals is the area of their surface exposed to the supersatu rated syrup. The exact weight of the initial individual small grains when they are formed is a very difficult m atter to deter mine. They are of microscopic proportions. Perhaps a prac tical example m ight shed some light on the subject. In a large sugar factory it has been found possible to seed completely a 14-ft vacuum pan w ith about 10 lb of extremely fine sugar. The final strike produced about 72,000 lb of com mercial product. No new crystals were formed during the strike, which contains the same number of crystals as were in the original 10 lb of seed. From this it may be seen that for each individual crystal: (1) The increase in weight and volume was 7200 to 1 (2) The increase in crystal surface was 361 to 1 (3) The increase in linear dimension was 19 to 1. reached a high point, in the neighborhood of 1.35 to 1.40, at which spontaneous formation of crystals took place of its own accord w ithout any external influence or manipulation. That is to say, fine microscopic grains of sugar began to form in the heavy syrup. (2) Another very popular method of starting Crystallization in vacuum pans is the so-called " shock system." The pro cedure consists of drawing in a certain limited quantity of fine sugar crystals, w ith the simultaneous admission of air, when the supersaturation has reached a point established at approxi mately 1.20 plus. The shock produced by the presence of these crystals accompanied by the inflow of air causes a new crop to form much before it would in the aforementioned "waiting method," and as a rule, a more uniform and satisfactory grain. (3) The third method is by "seeding," or the introduction into the strike of the full number of fine crystals which will eventually grow to the ultimate size required without the for Contributed by the Process Industries Division and presented at the Annual Meeting, New York, N. Y., Dec. 2-6, 1935, of T h e A merican Society of M e c h a n ic a l E n g in e e r s . mation of new grain. In this case the seed is introduced just after saturation has been reached. Various authorities advise different procedures as to the quantity and fineness of the seed. 100 M echanical Engineering How far this can vary will be understood from the fact that it is possible to seed a 14-ft vacuum pan w ith as little as 10 lb of fine sugar. On the other hand, two or three tons may be used. In this instance, the size of the seed is proportionately much coarser. In other words, there would be the same number of crystals in the 10 lb of seed as there is in the charge of two or three tons, if the same coarseness of ultimate sugar is to be made. Outside of the inconvenience of handling the large bulk, the advantage is in favor of the large seed. The crystals have much more accreting surface and thus avoid a difficult stage in the operation of controlling the growth at the beginning, which has always been a ticklish matter. PREPARING THE GRAIN Having the starting nuclei in the pan, obtained by the w ait ing method, the shock system, or the seeding system, the next step is the preparation of these crystals for further growth, or, as they say, "hardening the grain." Stripped of all unneces sary verbiage and local terminology, this consists of preventing the formation of new grain while at the same time causing the existing crystals to grow at the maximum possible rate until they are large enough to absorb the sucrose from the surround ing syrup as fast as it is made available by evaporation. This sounds easy, but it is the most critical stage of the entire opera tion of sugar boiling. The reason is not difficult to find. It has been mentioned that it is possible to seed a 14-ft vacuum pan w ith 10 lb of fine sugar. For the sake of simplicity, let us assume th at this quantity of sugar nuclei is present in the 14-ft strike at the start, irre spective of the method by which it has been obtained. The rate a t which these crystals can be made to grow depends principally upon tw o factors, namely, the supersaturation of the syrup and the surface of the crystals. It is generally conceded that maximum rate of growth will be obtained when the super saturation is in the neighborhood of 1.20. This varies somevvhat w ith the purity, but the point is th at there is a maximum concentration for fastest crystal growth, and if this is exceeded, not only w ill the accretion of sucrose on the crystals be im peded, but there is imminent danger of forming undesired new crystals; "false grain." If the concentration is too low, then the rate of crystal growth will decrease also, and stop alto gether when saturation is reached. Since at the start the sum total of the surfaces of the crystals present is only V361of what it will be at the end of the strike, it is evident that it is possible to make sucrose available by evaporation much faster than it can be absorbed by the sugar crystals; hence, if evaporation is allowed to go on unrestricted, the supersaturation will rise and false grain w ill come in. On the other hand, active masseeuite movement must be main tained for uniform crystal development, and this movement can not be achieved without evaporation, and thus a dilemma. There are several methods of solving the problem. One is to feed water into the pan, so-called "movement w ater," which is adm itted a t a rate sufficient to prevent excessive supersaturation, while the rate of evaporation is maintained fast enough to give the proper circulation and movement. As the crystals grow and acquire more and more surface for sucrose absorption, less and less movement water is used, until, in a short time, it can be stopped altogether, since the rate of sucrose absorption by th e new enlarged crystals now equals or exceeds the rate at which it can be made available by evaporation. From now on the condition is no longer critical. Another method in quite g en eral u se is t o lo w e r the vacuum, thus raising the temperature, and decreasing the supersatura tion w ithout using movement water, until the crystals have grown sufficiently to absorb sucrose as fast as it is made avail able by evaporation. This sudden increase of temperature is usually supplemented by giving the strike a "drink" of light syrup, further to reduce the supersaturation during this difficult period. This is the usual procedure after the waiting method and also after shocking. It may also be used after seeding. The technique varies w ith locality and tradition. It is defi nitely objectionable to feed water into the strike, as it has to be evaporated for nothing, and locally may dissolve some of the fine grain. Mechanical circulation produces movement without evapo ration, and here it is possible to " hold everything," allowing the circulator to operate w ith steam cut off and vacuum fixed, if necessary, until the required preliminary crystal growth has been obtained. In fact, w ith control instruments, the ad visable thing to do is to hold the vacuum steady and adjust the steam supply to maintain the supersaturation at the desired point. Particular care must be exercised in the control of the vacuum, as a change here is immediately followed by a change in temperature, and hence a change of supersaturation. False grain is sure to appear if the temperature is lowered while the strike is in this critical state. There is some diversity of opinion as to the best plan to follow after this grain preparation has come beyond the critical stage. Some advise not to carry the strike too "tig h t" on the assump tion th at tightening it will increase the supersaturation, and, therefore, bring out the false grain. We are decidedly in favor of tightening the strike, and this is one of the reasons why this paper was written. The explanations follow: WHAT HAPPENS W H EN A STRIKE IS TIGHTENED In a recent paper1 a fairly detailed discussion was given of what happens when a strike of sugar is "brought together." It is quite appropriate to review some of the points brought out bearing strongly upon this discussion. Very accurate in struments were used in profusion, and it was possible definitely to establish the following points: When the strike was brought together (1) The boiling-point rise went down, as did the supersatura tion. (2) The rate of evaporation increased more than 40 per cent. There is a definite limit in bringing the strike together, which must not be exceeded. If this limit is passed, the strike be comes so stiff that circulation is impeded, and evaporation re tarded. It has been well established that for high-purity strikes the reactions just stated invariably take place. There is a delicate point in the transition of physical condi tions while the strike is being brought together. Apparently, the crystals will absorb sucrose much faster when they are close together. Not only will the growth be faster, but the danger of forming false grain practically disappears. It must be restated that the critical point must not be exceeded. The only accurate way to determine this is by the use of a steamflow meter attached to the supply of heat to the pan. When this instrument shows a maximum steam flow, that is the right point and the best point for the strike. BALANCE BETWEEN HEAT SUPPLY AND CRYSTAL GROWTH .Going back to the m atter of crystal surfaces which determine the rate at which sucrose can be absorbed from the syrup, con sider the example given at the beginning in which it was shown that total surface of the sugar crystals at the end of the strike was 361 times as great as it was when the pan was seeded. A 1 "The Design and Use of Vacuum-Pan Control Instruments," by A. L. Webte, Industrial and Engineering Chemistry, vol. 27, October, 1935, pp. 1157-1161. February, 1936 101 natural question would be to ask what influence this fact has on the operation of the pan. It is felt that when ideal supersaturation is maintained, maxi mum and most uniform crystal growth takes place. This super saturation may be 1.15,1.20, or 1.25, more or less, according to the purity. At a certain point, when the grain has been finally prepared, w ith this ideal supersaturation, a balance is obtained between crystal growth and the rate at which sucrose is made available in the syrup, which in general corresponds to the rate of evaporation. Soon, the possible rate of crystal growth exceeds the rate at which sucrose can be made available by evapo ration, and toward the end of the strike the former exceeds the latter many times. Under these conditions, the necessarily decreased rate of crystal growth brings about an automatic reduction in the supersaturation .of the syrup between the crystals, as this is the only way the balance can be established. It easily explains the reason why the strike is brought together and the rate of crys tal growth increases the boiling-point rise-, and hence the supersaturation, decreases. This, in turn, decreases the vis cosity of the syrup, and hence permits an increased rate of evaporation, other things remaining the same. As was mentioned in the reference,1 the controlling factor is no longer the supersaturation, but the fluidity of the mass as a whole. This fluidity is a function of the ratio between the volume of the voids between the grains of sugar and the volume of the syrup in the pan and is not necessarily a function of the concentration of the syrup or of its viscosity--a very in teresting conclusion indeed, and one to which consideration must be given. CONDITIONS FOR CRYSTAL GROWTH No one is justified in assuming that ideal conditions for the growth and development of sugar crystals are obtained in the average vacuum pan. It is necessary to face the facts and ana lyze them. Fundamentally, it is known that crystals grow in a supersatu rated sugar solution. This supersaturation can be increased in two ways, namely, by evaporation of water or by lowering the temperature. Conversely, it can be reduced by diluting with water or by increasing the temperature. Any tw o of the four reactions may be combined w ith corresponding results, except heating and cooling. Let us consider w hat are the ideal conditions for satisfactory crystal growth, after which the pan operating conditions can be examined to see how closely the requirements are met. In the first place, the supersaturation must not exceed the limits set for the purity of the syrup being used, otherwise, the growth of the crystals w ill be retarded and there is danger of forming false grain. In the second place, in no part of the pan at any time must we have local conditions of unsaturation, as in this case the crystals already formed w ill dissolve in the syrup. In the third place, for uniform and rapid growth, there must be considerable motion in the mass. Since sucrose is absorbed by the surface of the individual crystals, the tendency is for the film next to the crystals to approach saturation at which sucrose absorption ceases, so that this film must be changed and re placed by new rich syrup if growth is to be maintained. This is true with high-purity syrups, and much more so if the purity is lowered, in which case the unabsorbed impurities insulate the crystals from contact w ith available sucrose and make fu rth e r accretion difficult, if not impossible. This establishes the necessity of uniform conditions as regards concentration of syrup and movement of the mass, and no such conditions are to be found in either coil or calandria pans of the average design. It has been established2 beyond any doubt whatever that temperatures in vacuum pans are subject to un believably severe variations during even carefully controlled operation. The magnitude of these local temperature varia tions is of the order of 50 F, or even more under bad conditions. Of course, it can be easily shown that if syrup at a normal super saturation of 1.20 in a panful of massecuite is heated 50 deg, it will be much below saturation, and Table 1 will give a fair idea of the extent of the change. A study of this table shows that an increase in temperature of 25 deg will practically bring the concentration of the syrup right down to saturation, and anything above this will bring about a condition of unsaturation wherein sugar will redissolve into the syrup. In view of the data brought out in the begin- TABLE1 SHOWING THE EFFECT OF TEMPERATURE INCREASE ON MASSECUITE SUPERSATURATED AT 1.20 (For normal supersaturation 1.20, new supersaturation for increases of temperatures) Theoreti cal temp, F 10 deg 20 deg 30 deg 40 deg 50 deg 60 deg 120 1.14 1.08 1.02 0.94 0.89 0.83 130 1-13 1.07 1.00 0.94 0.87 0.81 140 1.13 1.07 0.99 0.93 0.86 0,78 150 1.13 1.05 0.97 0.91 0.84 160 1.13 1.05 0.97 0.89 170 1.12 1.03 0.93 180 1.11 1.02 ning, it will be realized that for the largest part of the strike the supersaturation is probably not more than 1.10 and may be even less than that. If such is the case, fluctuations in tem perature will be much more harmful, in that an increment of only 12 deg will remove all supersaturation. Since these conditions are purely local, it is evident that some crystals will suffer and others will not, making for size irregu larities, not to mention local increase of syrup concentration due to the dissolution of already crystallized sucrose. This latter condition can cause bad results when the mass reaches the sur face of ebullition, for the supersaturation will suddenly become excessive, locally, resulting in false grain, conglomerates, mo lasses inclusion, and what not. It must be emphasized that these conditions are in no way exaggerated. They actually exist and can and have been ob served, as has been pointed out in another paper.3 Since it is known that ebullition takes place far below the surface of the massecuite, at such points temperatures are reached which cor respond to the reduced vacuum due to the superposed hydro static head, and this would easily account for variations of the magnitude mentioned above. When all this is fully appreciated, it is a wonder that it is even possible to make satisfactory sugar in many vacuum pans of w hat has generally been considered standard design. Turning back now to the question of movement of the crystals in the mass, further elaboration is necessary. In the ordinary pan all movement is due to ebullition which is really what causes circulation. Temperature conditions have little to do w ith movement, except in so far as they bring about the forma tion of bubbles of vapor under the mass. In other words, cir culation is caused by boiling. It is interesting to note that at the locus of the heating surface there is either ebullition and motion, or absence of ebullition and stagnation. With ebulli- 2 "Circulation in Vacuum Paris," by A. L. Webre, Trans. A.S.M.E., 1929, pp. 913-922, paper PRO-56-1. 3 'Temperature Conditions in Vacuum Pans," by A. L. Webre. Pre sented before a meeting of the International Sugar Technologists, at Brisbane, Australia, in August, 1935- 102 M echanical Engineering tion, the temperatures existing at these points must be high enough to correspond to the boiling temperatures due to the reduced vacuum, which is simply another way of proving the inevitable presence of local hot spots. This cannot be avoided if operation is to go on, and for th at reason, until recently, it has been found necessary strictly to limit the height of the strike above the lowest heating surface in order to avoid these excessive local temperatures. It is a quite well-known characteristic of vacuum pans that they boil much slower as the strike is higher, and hence the motion is most sluggish when the danger of overheating is greatest, thus vitiating the entire cycle. Our tests on standard raw-sugar vacuum pans have shown the following, for strikes about six feet above the heating surface: 1 Type of strike (14 ft) Maximum evaporation, lb pec hr Minimum evaporation, lb per hr "A" (80 pur.) B" (70 pur.) "C" (58 pur.) 30300 23900 17850 15250 12600 1150 (Note that the worst variations are for the low grades, the most dan gerous strikes.) MECHANICAL CIRCULATOR PERFORMANCE In reality it was as a result of these pan investigations that we decided it was practically impossible to approach ideal condi tions w ith natural circulation in vacuum pans. It is not claimed th at the mechanical circulator enables us to operate under perfectly ideal conditions. However, the operation has been so greatly bettered th at a radical improvement has been achieved. Whereas there are still observable temperature variations, their magnitude has dwindled down to negligible proportions, thus minimizing the ill effects outlined. The complete elimi nation could only be accomplished at an altogether unjustifiable expense. The motion of the massecuitc is at a certain definite constant rate independent of the rate of evaporation, the purity of the massecuite, the steam pressure, or the vacuum. It is governed simply by the volumetric displacement of the circulator. As far as movement is concerned, it is adequate for all practical purposes, and under complete control. As regards the influence of height of the massecuite on the making of the strike, this has completely disappeared, and per fectly good strikes are being made as high as 14 ft above the top of the heating surface. The most remarkable feature has been the maintenance of sub stantial uniformity in the rate of evaporation from the begin ning to the end of the strike, another large step toward the absence of variations so desirable for the proper elaboration of massecuite. Sugar-fabrication men are quite familiar w ith the characteris tic sluggish operation a t the end of the strike when it is brought together. This feature also has almost disappeared. Highpurity strikes come together in about three minutes, whereas low grades take proportionately longer. Greatly increased heat transmission brought about by proper mechanical circulation makes possible the use of juice vapors at low temperature, even under partial vacuum. This not only effects a large steam saving, but allows the making of strikes w ith a minimum of heat injury. The most significant gain, however, is in the uniformity of size and shape of crystals. From the viewpoint of the rawsugar factory, it is well known that bad grain invariably results in sugar of low filtrability, and hence undesirable and of poor marketing value. From the standpoint of the refinery, uniformity of size and shape of crystals is still more important. Irregular shape and lack of uniformity produce sugar which becomes lumpy and unsalable, even after moderate storage. Furthermore, due to lack of heat injury, the color of the sugar is always white, and serious losses by temperature inversion are avoided. These results are directly attributable to the use of the me chanical circulator. Nesmith OCCUPATIONAL DISEASES Additional Responsibility Legislation Places On Industry B y HENRY D. SAYER ASSOCIATION OF CASUALTY AND SURETY EXECUTIVES, NEW YORK, N. Y. NOT many years ago legislators and industrialists re sponded to the new doctrine of compensation for indus trial accidents w ithout regard to fault as a causative factor. So familiar has this compensation principle become that it is virtually unanimously accepted by employers, and this idea th at was so revolutionary only a short twenty years ago is now an accepted rule of industry. Its burdens have not been lessened as time has passed. On the contrary, compensa tion costs have steadily mounted. But industry long since learned to absorb those costs and to assume those burdens, even though frequently a t the cost of great hardship. Entirely aside from the monetary benefits to injured workers and the dependents of deceased employees, the tw o great out standing benefits to workers through the compensation system are (1) the reduction of accident frequency brought about by the promulgation of safety standards and by good engineering, and (2) the reduction of accident severity, by the requirement for prompt medical and surgical care at the expense of the employer. These are the positive sides of compensation for accidents, and employers may well take pride in the accom plishments of industry, of medicine, and of engineering in these lines. RECENT LEGISLATION ON OCCUPATIONAL DISEASES WIDESPREAD Just as twenty years ago there was the insistent demand for compensation for accidental injuries, so now there is an ever growing demand for legislation for compensation for industrial diseases. This is no new thing to us here in New York. We have had an occupational-disease statute since 1920. Three or four other states have rather full occupational-disease laws, while some others have laws of somewhat limited application. But in the greater number of states, no provisions have been adopted for compensation for occupational diseases. The essence of the idea of compensation for occupational diseases is th a t disability or death from a truly occupational disease is just as much the responsibility of industry as is such a condition resulting from industrial accident. With this principle it is hard to disagree. Few there are who will say th at the workman who suffers a disability, who is de prived of the means of a livelihood through a disease or sick ness th at came upon him only because of his exposure in his work to the deleterious effects of some poison or some chemical, some dusts, gases, or fumes, is not equally entitled to compensa tion w ith his brother whose disability came on him by reason of an accident. In principle both seem alike. So prevalent is this idea that in the legislatures of 18 states bills were introduced last winter newly providing for occupa tional diseases or for enlarging the existing laws. In a number of states provision was made for the appointment of interim legislative committees to study and report on the subject of occupational-disease legislation at the nexrt sessions. Un- Contributed by the Safety Committee and presented at a session on Occupational Diseases at the Annual Meeting, New York, N. Y., Dec. 1935, of T h e A m e r ic a n So ciety oe M e c h a n ic a l E n g in e e r s . Slightly abridged. doubtedly, another year w ill see legislative attempts in many more states. In great part these efforts were not successful, but a renewal of them is inevitable. Employers will have to prepare to meet the added burden of such laws. Just as in time the cost of compensation for acci dents was absorbed,: so too w ill the cost of compensation for diseases in time be absorbed if right principles prevail and if the effort is not made under the guise of compensation to charge employers w ith general health and life insurance of their workers. But it is not certain th a t correct principles will always be observed. The temptation is great to give to the oppressed and distressed--out of the other man's funds! To be the public almoner of industry's money must be a comforting thought to some public officials--especially at election time. NECESSARY TO SAFEGUARD AGAINST ACCRUED LIABILITY We must, therefore, be vigilantly on guard to demand in all such legislative efforts a recognition of sound principles and policies, and insist that such laws do not throttle the industry itself. It is essential that we insist on at least two safeguards: (1) To guard against the already accrued liability, and (2) to make certain th at compensation shall be payable only for diseases that are truly occupational. What is meant by the term accrued liability is illustrated by what has recently happened in New York. The New York state law is what is known as a schedule law, that is, the law itself contains a list of diseases or poisonings with a parallel column listing the occupations or processes in which such con ditions usually occur. Thus, to use a common illustration, lead poisoning is listed as a disease, and is compensable when in curred by a worker engaged in any work that causes him to use or be exposed to lead. This, it will readily be seen, is truly an occupational disease, readily recognizable as such, and is a definite pathological entity. Seldom is the disease found ex cept among lead workers, painters, and the like. The schedule in the New York act had been enlarged from time to time until it included practically all known occupa tional diseases w ith the exception of lung diseases attributable to dust. It is generally conceded that these dust diseases call for special provisions of law and for different procedures. The effort to provide such special provisions proved abor tive, and when the legislature passed a general all-inclusive provision to cover in broad terms " any and all occupational diseases," it swept in under the law all dust diseases along with the rest. So m e o cc u pa tio n a l d isea ses a r e of slo w d e v e l o pm e n t Now by the very nature of these diseases they are of slow, progressive development. Silicosis, or a fibrous condition of the lungs resulting from the inhalation of silica dust, requires a minimum of five years of exposure to produce disability, and many authorities assert that the progression to disability takes from ten to fifteen years. In all these diseases, there comes a time when regular work is not possible. This is called in the 104 M echanical Engineering law " disablement." The moment the wide-open law went on the statute books, it created a liability for many years of expo sure that had already taken place among thousands of workers. Industry found itself faced with the problem of paying for con ditions th a t arose at a time when the law imposed no special duty on the employer to pay for the condition or to take effective measures to prevent the disease. While industry cannot assume safely such a burden, neither can insurance be asked to take it on. Payment for losses that accrued prior to the insurance contract is not in any sense in surance; insurance is the assumption of liability for a contin. gency or for a fortuitous future happening. The result of the new law in New York has been disastrous. Premium rates were set at prohibitive figures. Where dust exposures existed supplementary rates were added to the regu lar already high compensation rates. These supplemental rates ranged from the lowest at something more than a dollar per hundred dollars of payroll up to as high as twelve and thirteen dollars a hundred. The total compensation cost, therefore, for many industries has risen to more than twenty dollars. When this is compared to the comparatively low compensation cost in states where such liabilities have not been imposed on industry, it will be readily appreciated how difficult it is for New York industries to survive under competition. Since September 1, 1935, the effective date of the new law, many plants have utterly closed down, some have gone on part time, others are contracting out to plants in other states that part of their operations which are involved in dust, and with it all, the worker may be said to be the sufferer through unemployment. Any attempt anywhere to impose on employers by law a burden of responsibility for diseases of past contraction will lead inevitably to such a muddled situation as exists in New York today. co m pen sa tio n sh o u ld b e c o n fin e d to t r u l y o ccu pa tio n a l DISEASES The second principle is that compensation shall be provided only for diseases truly occupational. The term "occupational disease" is in common use,, yet it has no fixed definition nor definite limitations. The effort is sometimes made to define it as a " disease that arises out of and in the course of employ m ent." Such a definition is thoroughly unsatisfactory. This terminology has been used probably because it has ample precedent in the field of accident compensation, but the condi tions surrounding accidents and those surrounding disease are so radically.different that the same terms w ill not do. Shall we say that heart disease, tuberculosis, pneumonia, pleurisy, head colds, and all the multitude of human ills shall be deemed occupational when they occur among workers and it is claimed th at some act or incident of the employment caused or contributed to the disease? If so, it means nothing less than general health and life insurance for workers at the employer's expense. This is not a burden that industry should or could bear. An occupational disease is not a disease of ordinary life, but a disease " characteristic of and peculiar to " the occupation. When speaking of disease, these words are far more definite than is the phrase " arising out and in the course of" employment. They should be used wherever it is impossible to have a schedule or listing of diseases. This qualification has received the approval of the State In dustrial Board in New York. As yet there has not been suffi cient time for a case to arise under it and be passed on by the courts, but it is greatly to be hoped that the courts will follow this view of occupational diseases. There is another, and to engineers a very important, con sideration in favor of the schedule method of covering occupa tional diseases, rather than the general all-inclusive method and that is prevention. Prevention is the key to the occupa tional-disease situation. Just as the engineers took up the challenge in the field of industrial safety when accident-com pensation laws came into operation, and have done a magnifi cent job, so they w ill have to take over an intensive study of the means and methods of prevention of disease. They have learned that good results are obtained only when they can concentrate on some special problem or on some phase of a problem. . How better can the engineer concentrate on occupationaldisease prevention than to start out with a named list of diseases set forth in the law? It is often necessary to appeal to employers or management to take certain steps in throwing up safeguards, and these cost money. If the engineer is dealing with a definite schedule of diseases he looks for the conditions in a plant from which those diseases may arise. He can tell management th at if lead is used workers must be safeguarded from it. That is ele mentary. But without the law suggesting it, how many would think to guard against chrome ulceration, or adequately safeguard workers coming in contact with or using methyl chloride, or any of the other many conditions included in the occupational-disease schedule? SAFEGUARD AGAINST EVERYTHING It may be suggested: Safeguard against everything. How ever, no matter what attempts are made, no matter how willing the employer to go along w ith the plans, under any blanket plan some dangerous conditions will certainly be overlooked. And from the standpoint of bringing to the employer the necessity of spending money in disease prevention, it is hard going to convince him th at he has a disease hazard warranting the expenditure of large sums unless the law gives the clue to the diseases to be guarded against. Only by the slow laborious process of picking up diseases as they occur and are made com pensable over a period probably of years will we get effective prevention work, unless the scientific knowledge of diseases and industrial processes now possessed by public authorities in the field of industrial hygiene is made available to industry through writing it into the statute. That new burdens are being imposed on employers by recent legislation or are impending in the demand for new legislation must be recognized. There will be no turning back in this field, any more than there will be turning back in the field of compensation for accidents. If, however, we are wise, we will give heed to the lessons we have learned out of an abundant experience in accident compensation. The same motivating factors will be present in this new field; the same liberality, the same generosity w ith the employer's moneys. The cure for all the workers' ills will be attempted through these laws. Vagueness and lack of definition but play into the hands of the overliberal. We should insistently demand that occupational-disease legislation be intelligent, certain in terms, and properly safe guarded against already incurred liabilities. Let the em ployer's responsibility be expressed in understandable terms and with a scrupulous regard for the ability of industry to carry the increased load. And above all insist that the law be so worded as to make effective prevention work possible. By so. doing, and only by so doing, will industrial justice be done and effective steps taken to carry industry's part in the field , of the true occupational disease. Engineering Control of OCCUPATIONAL-DISEASE HAZARD B y WARREN A. COOK CONNECTICUT STATE DEPARTMENT OF HEALTH IT IS the purpose of this paper to outline a practical procedure which the .engineer can employ in his own plant to assist in che control of occupational-disease hazards. The solution of the occupational-disease problem is by no means a one-man job; it requires the active cooperation of all concerned, the engineer playing a large part in its successful solution. He is more than an important cog in the wheel; he is a vital center in the mechanism for control of industrial health hazards. The mechanism to be set in motion for provision and main tenance of healthful working environment is, within limits, much the same whether the engineer is associated with a large manufacturing organization or w ith a small unit. The first step for the engineer to take is to ascertain just what hazardous materials, processes, and conditions exist in his plant. We all know generally that a variety of organic solvents are used in spray lacquers and thinners, that grinding wheels are made up of various types of abrasives. But such generalized information is not sufficient. It is essential that the engineer know specifically every potentially hazardous material used in his plant. tin presents a list of hazardous occupations and the injurious materials and conditions which may be associated with them. The potentially hazardous materials to which workers were exposed in a group of plants in a typical industrial area are listed in the report2 of a survey recently conducted by the United States Public Health Service. This report includes the number and percentage of workers exposed. It may also assist in compiling the list of such materials used at: your plant. The permanent record of the potentially hazardous materials and the opeFations w ith which they are associated may well be compiled in the form of the potential-health-hazard chart pre pared by our bureau, in which the injurious materials are listed along the abscissas and the industrial classifications along the ordinates of cross-section paper. In the chart which you make up for your plant, the individual departments and operations will be substituted for the industrial classifications. The in formation given by this chart may be made more complete by inserting, instead of the X used in our chart, the number of workers exposed together w ith a symbol to indicate the relative severity of the hazard. LIST THE MATERIALS THAT ARE HAZARDOUS LEARN W HAT PROPERTIES OP HAZARDOUS MATERIALS AFPECT HEALTH This then is the first item of the practical procedure to follow: Go through the plant, department by department, and list the materials used in or given off by each operation. You may be of the opinion that you know all these items as part of your intimate knowledge of the plant. But it has been our experience when making plant surveys th at there are usually a number of gaps in the engineer's knowledge of these materials. Do you know, for example, whether the thinner used in your plant contains benzol as a constituent, whether gasoline for nonfuel purposes is free from lead, whether sandstone grinding wheels are employed, and w hat abrasives are used on made-up wheels or disk grinders? A complete survey of plant conditions will disclose such information and provide information on the potentially hazardous materials w ith which you have to contend. Since new materials are constantly being introduced, have a standing arrangement w ith the purchasing department to keep you informed of any such materials ordered. If it is decided to substitute methanol for denatured alcohol, it may not be neces sary to make any mechanical changes in a process and you may not be notified of the substitution. But you should know that this more hazardous solvent has been introduced, as additional control measures may be required. One of the surest methods of keeping your permanent record up to date is to have the purchasing department transmit this information to you. Of assistance in compiling the list of injurious materials used in the plant is the bulletin, " Occupation Hazards and D iagnostic Signs," prepared by Dublin and Vane.1 This bulle 1U. S. Bureau of Labor Statistics Bulletin No. 582, 1933. _ Contributed by the Safety Committee and presented at a session on Occupational Diseases at the Annual Meeting, New York, N. Y., Dec. 1935, of T h e A m e r ic a n Society or M e chanical E n g in e e r s . Having made a complete permanent record of the materials used, including their constituents, and of the departments and occupations where they occur, be sure that you are informed on the properties of these materials which affect health. You should know relatively how much of the material is required to cause injury and, generally, how the material affects the body. You should be sure th at your information is reliable and that it is in accordance w ith up-to-date knowledge and opinion. Research on this subject is continually being con ducted and our knowledge of the injurious action of these materials extended. Occasionally, erroneous impressions of the hazards presented by various materials gain credence and must be corrected. Some years ago the textbooks stated that pneumoconiosis was caused by sharp-edged dust particles such as those of granite and aluminum oxide. It has since been shown that the sharpness or hardness of the dust particles is not the criterion of their pneumoconiosis-producing properties and that workers exposed to sufficient concentrations of quartz dust to cause pneumoconiosis do not develop this condition when exposed to similar concentrations of equally hard and sharp-edged aluminum-oxide dust. Many engineers have a good conception of the types of dust which are most injurious, but erroneous impressions come to light when industrial health hazards are discussed. For example, we often find that the engineer fails to recognize that carbon tetrachloride is injurious on its own account but has the m isco n cep tio n t h a t only its products of hydrolysis when used in extinguishing fires are hazardous; and again that toluol is noninjurious since it was recommended 2 "The Potential Problems of Industrial Hygiene in a Typical Indus trial Area in the United States," by Bloomfield, Scott, and Sayers, Public Health Bulletin No. 216, December, 1934. 105 106 M echanical Engineering as a substitute for the more toxic benzol. The facts are th a t all the organic solvents are toxic, though to varying degrees. So although you cannot expect to know the whole subject of industrial toxicology, it is important th at you be reliably in formed on the injurious properties of the materials used in your plant. Such information can be obtained from some of the recent general references on the subject, or, even better, from such sources as your plant physician, federal and state bureaus of industrial hygiene or occupational diseases, insurance engi neering departments, universities, and private consultants. DETERMINE WHICH POTENTIALLY HAZARDOUS MATERIALS, PROC ESSES, A N D CONDITIONS ARE ACTUALLY CAUSING INJURY TO HEALTH OP THOSE EXPOSED The third step in the procedure of controlling occupationaldisease hazards is to decide which of the potentially hazardous materials, processes, and conditions are actually causing in jury to the health of those exposed. These potentially hazard ous conditions will fall into three categories: Those obviously requiring control measures, those which may be considered negligible, and those which require determination of the exposure to show whether or not the potential hazard may actually be affecting health. The use of determinations of atmospheric contaminants has been emphasized in the Connecticut Bureau of Occupational Diseases as an exceedingly satisfactory basis on which to proceed. Engineers are trained to work from facts; the results of determinations of injurious materials in the air are the fundamental facts in occupational-disease control. The following experience shows w hat can happen when in formation is lacking concerning the exposure of workers to potentially hazardous conditions. Eighty men were con nected w ith a department in which two machines involved the use of one of the newer organic solvents th at had been shown to be only moderately toxic. Eleven of these men were di rectly engaged in the operation of the machines. The process had been in use for some time when an alteration was made which increased the concentration of the vapor and duration of exposure of the workers. Even w ith the increased concentra tion of the vapor, the odor was not unpleasant nor, as far as we know, did it cause the workers to complain. W ithin a fortnight, one of these 11 workers, a normally healthy young man, 29 years of age, went home after the extra long Sunday shift of 12 hours feeling ill. He died six days later, the cause of his death being attributed to influenza and dilated heart. No cause-and-effect relation was linked at that time between his occupation and his death. On the Sunday following, a second man working at these machines was taken ill, and on the next day a third. Cases 2 and 3 were still ill when two more workers were transferred from workroom to hospital; and within 14 days from the death of the first victim, five workers had succumbed to fatal poisoning. The point of this illustration is not that the organic solvent was extremely poisonous nor that it should necessarily be re placed by some less injurious material. There is no question but w hat the process, employing the very same solvent th at caused the deaths, could have been conducted in such a manner as to cause no injury to health. The point is that the engi neer in charge of the operation did not recognize his responsi bility to ascertain definitely whether the exposure to the solvent vapor was within safe limits. Had vapor determinations been made at the time the process was changed, the hazard could have been controlled before the injury to health occurred. Materials of equal or greater toxicity are being used in many plants today. If any change is made in an operation or in the material used, ascertain th at such change does not increase the hazard beyond safe limits. Only by knowing the hazards and determining that the exposure to them is w ithin safe lim its can you be assured that your plant will not be visited by any such lamentable occurrence. Not only do determinations of these atmospheric contami nants show where control measures must be instituted but, in other instances, they may permit appreciable saving by showing th at control measures involving expensive exhaust equipment may not in every case be necessary. Illustrative of such a situa tion is the potential hazard from the lead melting pot. For years there has been a tendency to recommend exhaust ventilation over melting pots containing lead and its various low-melting alloys in slush casting and linotype-machine operation. To determine just how necessary it is to have hoods over the melting pots of type-setting machines, air analyses were made in connection w ith an investigation of health hazards resulting from the use of these machine^ .3 The results of these analyses showed th at the daily exposure where there were no exhaust hoods was less than 0.2 mg. Studies made by our bureau where no local exhaust was applied to th e linotype machines have also shown lead concentrations of this same order, well below the amount which causes poisoning. In studies conducted in lead-casting departments of four plants during the past year, we found the exposure of the casters to vary from 0.1 to 0.5 mg of lead per 10 cu m of air. The amount of lead collected in samples taken directly over the melting pots varied from less than 0.1 mg to less than 0.4 mg per 10 cu m. Since it has been well established th at except for prolonged exposures the limit of safety under most industrial conditions is an atmospheric concentration of lead dust or fumes of less than 1.5 mg per 10 cu m of air, the foregoing determinations in dicate th at there are more important control measures than the provision of exhaust ventilation for lead m elting pots kept at moderate temperatures. Of interest in this regard is a table of the calculated maximum lead-vapor content of air over surfaces of lead kept at various temperatures from 250 C to 1500 C which was published in the foregoing paper.3 A portion of this table is reproduced in Table 1 . TABLE 1 CALCULATED MAXIMUM IEAD-VAPOR CONTENT OF AIR OVER SURFACES OF LEAD KEPT AT VARIOUS TEMPERATURES --------Temperature- C F Concentration of lead, mg per 10 cu m 300 572 0.00006 350 662 0.0016 400 752 0.02 450 842 0.2 500 932 2.0 From this table it w ill be noted thac-the temperature must exceed 900 F before injurious concentrations of lead vapor are given off from the melting pot. A warning should be given, however, th at as the temperature exceeds this value the amount of lead vapor evolved from the surface of the molten lead in creases rapidly; when the temperature doubles from 500 C to 1000 C the equilibrium concentration of th e lead vapor above the surface of the molten lead increases 50,000 times. Since things are not always what they seem, even when con sidering such a prosaic entity as occupational-disease hazards, the engineer should have information on the amount of the in jurious substance to which the worker is exposed wherever there is a possibility of doubt. Determinations of atmospheric, contaminants bring to light hazardous conditions before occu- 3"Hygiene in Setzmaschinenraumcn," by Vaje and Weber, Schrifterf aus dem Gesamtgebiet der Gewerbehygiene, no. 44, 1935. February, 1936 107 tional diseases develop. In former years the only criterion of the healthfulness of the industrial environment was whether of not clearly demonstrable injury to health occurred. And usually- it was necessary for several cases of occupational disease to develop before the working conditions were accepted as the aetiological factor. Utilize the methods available today to keep one step ahead of the occupational-disease specter. Determine whether the working conditions are safe or hazardous on the basis of the concentration of the hazardous material present. If the worker is exposed to more than the threshold dose, then act a t once to correct the condition. It is not necessary for the engineer to delay, fearing th at he may be overestimating the severity of the hazard and so letting his concern in for unessential and unproductive expenditures; he can stand behind his recom mendations when they are based on facts which show the hazard to be excessive. It has been our experience th at the engineer armed w ith such facts has received support from the management such as had previously been accorded him only on projects which offered an assured production profit. apply e n g in e e r in g pr in c iples to k e e p W ITH IN SAPE LIMITS w o r k b r 's e x p o s u r e This leads to the fourth step in the procedure for the control of occupational-disease hazards: The application of engineer ing principles to keeping the worker's exposure to potentially hazardous conditions within safe limits. As stated by Clark and Drinker in their new book, 4 ``Prevention of industrial disease is largely an engineering problem, as its basis is a separa tion of the toxic or irritating substance from contact w ith the worker." This separation of the harmful material and the worker may require application of the most ingenious engineering skill or merely of simple engineering principles, but in either case there should be a generous portion of th a t most valuable qual`Ijf~ ity, the ability to be practical. General methods of occupa tional-disease control measures can be divided into a number of groups, such as provision of enclosures, exhaust ventilation (both local and general), changes in process (dry to wet, for example), substitution of more toxic by less toxic materials, and wearing of special protective equipment. W ithout going into examples of each of these general meth ods, consider from an industrial-hygiene point of view some simple operation, such as sandblasting. Assume th at this operation is conducted in a modern, specially designed room, that the sandblaster is equipped w ith a positive-pressure helmet, that a steel abrasive is used, and th at a cloth-filter type of dust collector is provided. It may perhaps be felt th at the condi tion can be dismissed as completely satisfactory. But is the sandlbaster adequately protected? Let us see just what should be taken into consideration to assure that an affirmative answer can truly be given. The dust to which the sandblaster may be exposed comes from tw o sources, th at in the sandblast room and th at in the air line to his helmet. If there is an appreciable amount of molding sand on the castings being cleaned, the dust in the room w ill contain free silica, though the percentage will be considerably lower than if a sand abrasive were being used. The positive-pressure helmet may look good on paper, but examine it on the man to make sure it permits no easy access for the dust. W ith some types of helmets there is a strap or elastic which permits a tight fit around the neck. Does the sandblaster so adjust this that the dust cannot enter the breathmg space? Or perhaps there is an opening at the front' of the 4 `Industrial Medicine," by Clarke and Drinker, National Medical tok Co., New York, N. Y., 1935. helmet when he leans over in the course of his work. The ve locity of the dust is so great during sandblasting that it will find its way into the helmet if there are openings of appreciable size even against the stream of air escaping from it. Having ascertained that the helmet fits properly and is so adjusted that the dust does not have access to its interior, turn your attention to the air supplied in the positive-pressure line. How much dust does it contain? Is the intake of the compressor so located th at the air is clean? Even when an air washer is supplied we have occasionally found this to be ineffective if dust has been allowed to accumulate in it or if the water has evaporated or the glass cracked. And is a sufficient volume of air supplied? Does the valve on the air-supply line permit the sandblaster to reduce the volume of air below th a t necessary to make the helmet as effective as its manufacturer designed it to be? Possibly the air line contains some oil from the com pressor and the blaster may shut off the air to avoid the dis comfort at the expense of subjecting himself to a severe health hazard. Provide the man w ith a clean air supply and be sure he is getting the proper volume of it. Having checked these items, make a dust determination of the blaster's exposure while conducting operations in the usual manner. A determination of the free-silica content of the dust will assist in the interpretation of the result. But a good helmet will keep the exposure well below five million particles per cubic foot of air which is considered good performance whatever the free-silica content. After the actual sandblasting has been completed, are there other dusty operations which the blaster may include as a part of his duties? An approved filter-type respirator should be worn while performing incidental jobs involving moderately excessive dust exposures. Perhaps one of these jobs is emptying the dust: collector two or three times a day. In one case we made dust determinations of the blaster's average exposure while transferring the dust from the hopper of the collector into barrels and found it to be 324 million particles per cubic foot of air! Even this repre sented an improvement over a former condition since a canvas cover had been provided which extended the canvas discharge tube so th at it fitted over the top of the barrel. A t the p lan t' where this determination was made, the blaster was exposed for ten minutes twice a day to this high dust concentration. It is essential not only to keep the average exposure within safe limits, but also -to avoid exposures to greatly excessive concentrations for even brief periods. The importance of avoid ing such exposures is not limited to dusts but also applies to many other injurious materials found in industry, especially where the brief exposures are repeated day after day. There are several methods for removing the dust from the collector w ithout subjecting the worker to large amounts of it and some effective method should be utilized. In problems of this type the engineers of the equipment manufacturers are of much assistance. A survey of the sandblast operation should include exposure of other workers in its vicinity. Is the sandlbast room itself tight? Where is the dust collector discharged? There has been much discussion concerning the discharge of cloth-filter dust collectors back into workrooms where free silica is one of the constituents of the dust. The final answer to this question de pends upon the ability of the engineers of the equipment manu facturers to provide a collector which will clean the a ir suffi ciently and with such certainty when all operating factors are considered th at the worker is not exposed to an injurious at mosphere. The difficulties of dust suppression, the limitations of dust collection, and certain other factors cause the preponderance of 108 M echanical Engineering opinion at the present time to favor the discharge at a point outside the plant of air from collectors handling a dust of high silica content. However, in a particular plant under certain cir cumstances, it may be especially desirable to return the air from the collector to the workroom. If this is done, then by all means ascertain by dust determination that those employed in the workroom are not exposed to excessive dust concentrations, and further, institute a rigid routine of maintenance and check dust determinations to assure yourself that the dust exposure is being kept w ithin safe limits. INSTITUTE ROUTINES OF MAINTENANCE AND CHECK-UP The engineering control of any occupational-disease hazard cannot be attended to once and for all and then forgotten. Eternal vigilance, in the form of maintenance and check de terminations of the atmospheric contaminants, is essential to the complete solution of the problem. This is the fifth step in the engineering control of occupational-disease hazards. Maintenance is of such paramount importance in occupationaldisease control th at it should be made the subject of an entire paper. The following is an example of what can be done when such a piece of equipment as a dust collector is properly main tained under the direct supervision of the plant engineer. Dust collectors were connected to two sandblast-table rooms using sand abrasive. The collectors had been in continued use for six years. During this time they were thoroughly inspected and cleaned every month. Konimeter dust samples were taken at the discharge of the two collectors. These showed counts of 1.2 and 0.7 million particles per cubic foot of air for one of them, and, for the other, 3.1 and 2.8 million particles. A week later the second dust collector was checked w ith an impinger and a concentration of 2.35 million'particles was found in the exhausted air. This collector had been cleaned and inspected about three and one-half weeks previously. Another impinger sample was taken within a few days after its next regular cleaning and the concentration at the discharge was found to be only 0.87 million particles per cubic foot of air. After another two weeks, opportunity was taken to collect still further konimeter samples at these two dust collectors and average concentrations of 2.3 million particles and 1.5 million particles per cubic foot of air were found. The engineer who maintained these dust collectors in such excellent condition deserves much credit, which the engineers who originally designed the equip ment would gladly accord him. Other pieces of equipment than dust collectors also require adequate attention to maintenance to assure that a health hazard once controlled will continue to be controlled. CONCLUSIONS A procedure has been outlined for the engineer to utilize in his plant as his part in the control of occupational-disease hazards. (1) He should make a permanent list of the materials used in his plant and keep the list up to date. (2) He should be informed concerning the injurious proper ties of the hazardous materials used. (3) He should determine which of the potentially hazardous conditions are actually causing injury to health and should be controlled. (4) He should engineer the control measures, preferably checking the completeness of control by determinations of the injurious materials in the air breathed by the worker. (5) He should institute routines of maintenance and check up determinations. The manner in which this procedure could be followed was outlined in connection w ith the simple operation of sand blasting. This same procedure can be utilized for the control of health hazards of similarly simple operations or of the most complex operations where a variety of hazardous materials are involved. Every available aid should be made use of in coping w ith the occupational-disease problem to the end that the hazardous condition may be controlled before it manifests itself in the form of cases of occupational disease. FUNDAMENTAL FACTORS in the DESIGN of EXHAUST SYSTEMS > By THEODORE HATCH HARVARD UNIVERSITY BECAUSE of the widely varying requirements and limita tions ctf the vast number of industrial processes to which local exhaust ventilation is applied, the American Standards Association Safety Code Committee for Exhaust Systems proposes to develop separate standard specifications for each industry rather than one inclusive code. Several sub committees have been appointed or projected to deal w ith various industries. In addition another subcommittee, on fundamentals of exhaust systems, was formed whose function It is to formulate and arrange in useful form the basic principles of design common to all exhaust systems, which should be in corporated in the separate codes. Most state exhaust codes are based upon a few empirical specifications w hich have not been changed in any important respect since their formation. 1 These specifications are being applied today to the design of exhaust systems for processes never considered when the codes were prepared. In many cases the results have not been satisfactory; but, on the other hand, some highly efficient systems have been constructed. In no case, however, have the systems been described in terms of basic engineering specifications, nor has it been general practice to test new installations to determine the degree of dust control effected. Since state codes required only the de velopment of a definite amount of static suction, it was enough simply to check this value. Hence, the considerable experience gained in the design of exhaust systems has not been evaluated and systematized and made generally available to designing engineers. Personal experience still remains the principal guide to design. Two steps are necessary to correct this situation: ( l ) Formu late and present in a systematic manner whatever fundamental concepts and data are available at the present time and indicate the manner in which these influence the method of design; (2) analyze existing systems critically and summarize the basic data pertaining to them in useful form. The adoption of fun damental methods of design and. the systematic analysis of re sults accomplished are necessary in order to build up a body of technical experience to serve as a guide for future design. The Subcommittee on Fundamentals of Exhaust Systems has attempted to assemble in ordered fashion the underlying prin ciples of design and operation of exhaust systems and these are presented as a progress report for critical review.12 The sub 1A notable exception is the Wisconsin code. 2For the organization of the subject matter, the subcommittee has drawn freely from the manuscript of a book: "Industrial Dust: Hygienic Significance, Measurement, and Control," by Philip Drinker and Theo dore Hatch, to be published by McGraw-Hill Book Company. Contributed by the Safety Committee and presented at the Annual Meeting, Dec. 2-6,1935, of T h e A m e r ic a n Society oe M echanical En- OINe b r s . A preliminary report by the Subcommittee on Fundamentals of che American Standards Association Committee on Code for Exhaust Systems: Theodore Hatch, chairman; M. I. Dorian, W. M. Graff, Leonard Grcenburg, J. C. Hardigg, H. M. Nichols, W. L. Keplinger, G. E. San'rd, R. R, Sayers, and S. E. Whiting. ject may be presented under five headings: Hoods, piping, air-cleaning plant, source of suction, and construction and maintenance.3 EXHAUST HOODS In order to prevent the dispersion of contaminating material into the atmosphere, the force which causes the dispersion from the source must be destroyed or otherwise brought under con trol. The energy of dispersion is supplied in several ways. I Solid and liquid 'particles. (a) If the particles are large enough and are thrown off with sufficient velocity, they will be dispersed by the kinetic energy of their own motion, i.e., by dynamic projection. The energy supplied in this way varies with the size, specific gravity, and the initial velocity of the particles. () Microscopic particles cannot be dispersed any distance by virtue of their own kinetic energy because of their relatively great air resistance and small weight. CO Microscopic particles are dispersed primarily by the movement of the air in which they are suspended. II Vapors and gases. (a) The maximum velocity of diffusion does not exceed 1 fpm and this is therefore an unimportant dispersing force. CO Vapors and gases lighter or heavier than air rise or fall, but the velocity of escape is not high unless there is a consider able difference in density. Gases escape from pressure contain ers w ith velocities th at may be very high but such a source of contamination is best controlled by means other than exhaust ventilation. (/) Vapors and gases escaping into the atmosphere at ap proximately the same density and temperature as the room air are dispersed primarily by air movement. Thus, it may be concluded that the basic problem is to collect contaminated air rather than to remove the contaminating ma terial from the air. This concept is important because it directs attention at once to the primary point of attack, namely, the source of air motion. It follows from this th at prior to apply ing the exhaust hood every means must be taken to reduce the velocity of air movement around the process by eliminating or otherwise controlling the sources of air motion. There are numberless ways in which air movement is produced around manufacturing processes; the following classification of im portant sources is helpful: (a) Motion produced inherently by the operation of the process itself. Examples: Air thrown off by the fan action of a rotating grinding wheel; escape of air from a container as it is filled w ith a powdered material. (b') Air movement generated incidentally to the operation of 3 Criticism of the report and suggestions are invited, and should be sent to the Secretary, Subcommittee on Fundamentals, Exhaust Code Committee, American Standards Association, 29 West 39th Street, New York, N. Y. 109 110 M echanical Engineering the process. Examples: Escape of air past worn pistons on pneumatic tools; vibration of machinery. ( 0 Drag of air in the wake of large particles dynamically projected from their source, as from a grinding wheel. (d) External sources of air movement. Examples: Natural convection currents; motion due to the operation of nearby machines. CONTROL OF AIR MOVEMENT The best way to eliminate air motion generally suggests it self from the nature of the source. Thus, proper maintenance prevents air leakage around pistons. The vibration of ma chines is corrected by improved design and proper foundations. Relocating the exhaust port on a pneumatic tool directs the blast of exhaust air away from, instead of toward, the point of dust generation. A properly vented water seal on a digestion tank prevents the accumulation of excess pressure and sudden release of gas at high velocity. The scattering of dusty air from a container being filled w ith powdered material is most effectively minimized by using a collapsed container or by pro viding a suitable vent from the container to a safe point of dis charge. Air motion generated by the operation of the process itself can be eliminated in part by the application of suitable baffles and enclosures. Example: Locating a stationary disk as close as possible to the face of a rotating wheel materially reduces the fan action of the latter. The pulsating waves of air generated by a reciprocating part can be minimized by enclosing the part. In some cases, as w ith a rotating wheel, the housing can be de signed to direct the air movement into the exhaust opening and thus utilize the energy of the air for its own collection. It is impossible to eliminate all air motion by these direct means but such measures are of great practical importance. In general, more can be done in this way to reduce the size of the exhaust system, the power consumption, and the cost of opera tion than by the most elaborate method of hood design. The exhaust hood creates air flow from the zone of generation of the contaminating material toward the exhaust outlet. At any point, the velocity thus established must be greater than the outward velocity of the contaminated air; th a t is to say, all air movement must be turned toward the hood. This is ac complished w ith any kind of a suction opening provided air is drawn into it at a high enough rate. The object of hood de sign, however, is to accomplish the desired result w ith the lowest possible rate of air flow. This requires a knowledge of the laws governing the flow of air into suction openings. The following general rules should be observed: (a) Enclose the process as much as possible. The total rate of air flow into an enclosed or semienclosed hood is determined by two factors: ( 1) The air velocity through the openings in the enclosure must be great enough to prevent the escape of con taminated air at these points; (2) the velocity within the en closure must be high enough to prevent the settlement of unde sirable material--in certain cases no settling is permitted, in others, the velocity must not be high enough to carry away valuable product.4 (b~) An exhaust hood which does not enclose the process should be placed w ith the opening as close as possible to the point of generation of the contaminating material, since the air velocity in the zone of hood influence varies approximately inversely w ith the square of the distance from the hood open ing. 4 In the design of an enclosing hood, particular attention must be paid to securing tight joints around shafting, sliding, or other moving parts of the process which must extend through the enclosing wall of the hood. (c) Shape the hood and provide flanges and other guiding vanes to create maximum air flow from the area of contamina tion and the least possible flow from the ineffective areas in which no polluting substance is dispersed; e.g., back of the face of the hood. If the area of production is long and narrow, use a hood of the same shape. GO Locate the hood opening, or part of it, so as to utilize the directional tendency in the motion of the contaminating air for its own capture. There is a tendency for all suction openings, regardless of shape or size, to draw air equally from all directions. This tendency increases w ith the distance from the hood, so that beyond a certain distance the distribution of flow becomes prac tically the same for all hoods. Thus, the velocity 30 in. in front of a square hood is the same for a given rate of air flow when the hood has an area of 20 sq ft as when its area is only 1 sq ft. Because of this basic tendency, the distribution of air flow toward a suction opening cannot be materially altered by changing the shape of the opening but much can be accom plished by the addition of baffles and enclosures. In this re spect, a discharge nozzle is superior to an exhaust hood, since a given air velocity w ithin a fixed area at a certain distance from the opening can be established w ith very much less total air flow and power consumption by blowing than by exhausting. This fact can sometimes be utilized effectively in hood design, although the use of a positive air stream is objectionable for two reasons: ( l ) When a positive stream of air strikes a barrier, it immediately scatters and carries dust or other contaminants w ith it; when the flow toward an exhaust opening is inter rupted by such a barrier, on the other hand, the flow simply ceases; ( 2) eddies are set up at the boundary between a positive air stream and the surrounding atmosphere, thus causing the escape of some contaminated air. REQUIRED AIR VELOCITY The aif velocity which must be developed in the zone of hood influence is determined by the velocity of air movement to be overcome, the magnitude and direction of which depend upon many factors not subject to exact evaluation. The designer should be aided in making his estimate by the experience ob tained w ith previous installations, but at the present time al most no data pertaining to required air velocities are available. Certain theoretical considerations are of some assistance: ( 1) The velocity of diffusion of vapors and gases does not exceed 1 fpm; natural air movement in the room is generally higher, 25 to 50 fpm. It is reasonable to put the minimum air velocity to counteract natural convection currents at 60 to 100 fpm. (2) Vertical convection currents created over hot surfaces or by the escape of a lighter gas into air vary in velocity with the square root of the difference in the densities of the column of rising gas and a parallel column of surrounding air, thus V= K where V = vertical velocity at any point in the rising column, ft per min -- r = average density, lb per cu ft, of the air at various 44 points in the rising column above the level at which the velocity is measured and below the level where d\ = dz ~ = average density, lb per cu ft, in parallel column of " room air February, 1936 111 H -- height of column in feet up to level where dx = K = a constant V = required velocity through the open area below the hood, ft per min (3) It can be shown th a t large solid and liquid particles STATIC SUCTION AS AN IN D EX OR HOOD OPERATION thrown off by dynamic projection cannot be captured by an opposed air current because the velocity required is so high as t0 be impracticable. From the practical standpoint, the velocity required in most cases lies between one hundred and several hundred feet a minute. In the Wisconsin code ) ... the velocity of air motion in the plane area within the outer rim or edges of the hood and at all points of the source of contamination, ex cept as otherwise herein specified, will be not less than the following: For gases, 60 fpm. For vapors,'fumes, and dusts, as follows: (a) Where the outlet consists of an enlargement of the exhaust duct arranged to house only or in part, the source of contamination, 170 times the specific gravity of entrained materials in feet per minute, except that in no case shall the velocity be less than 500 fpm ... (b) Where the outlet consists of an enlargement of the exhaust duct arranged to house the operator as well as the source of contamination, 120 fpm. While these figures leave much to be desired, they represent a marked improvement over the common static suction index. Undoubtedly, the best way to determine the air velocity re quired to capture the contaminating material produced by a Static suction is commonly employed as an index of hood operation since it determines, in part, the rate of air flow through the hood. But more important determining factors are the area at the throat (where the static suction is measured) and the restriction coefficient, thus Q = 4000/4,/ V I where Q = air flow, cu ft per min At = area, sq ft / = a factor k = head, in. of water The throat area is specified in many codes and an average value of / = 0.7 assumed, in which case the value of Q is rigidly de fined. It would be better, therefore, to specify j2 and permit the designer to create this rate of flow w ith whatever combina tion of A,, / , and h is most desirable. The static suction values which have been determined by past experience to give satis factory results are thus readily converted into values of Q, the rate of air flow. particular process is by direct experiment. Two methods are available: (1) Isolate the process from other sources of con tamination, install an experimental hood, and vary the air flow until satisfactory atmospheric conditions are obtained, as determined by quantitative air analysis; (2) determine by visual inspection or another simple means, the minimum velocity necessary to turn the contaminated air into a small portable EXHAUST PIPING The purpose of exhaust piping is threefold: ( 1) To connect exhaust hoods to a central source of suction and air-cleaning plant; (2) to create the proper distribution of flow from the various hoods; (3) to insure adequate air velocity for the pneu matic transport of the collected material. testing hood by noting the distance from the hood to the point of generation of th e material to be captured when this occurs. Knowing the flow characteristics of the testing hood, and the total rate of air flow into it, one can quickly calculate the air velocity at the point in question. TRANSPORTING VELOCITY (1) Vapors and gases may be moved at any convenient ve locity, such as is used in general ventilation. In certain cases a drop in temperature causes condensation from the vaporous to the liquid state. Provision must be made for drainage or for REQUIRED RATE OE AIR FLOW INTO TH E HOOD maintaining the temperature. The required rate of air flow is determined by ( l ) the re quired air velocity at the source of contamination, and (2) the (2) Dusts require higher velocity for lifting than for hori zontal conveying, thus location and design of the hood w ith respect to this source. (1) Within a semienclosure Vertical: V = 1200 \ d - or V = 13,300 --7-- -57 IP v+ 1 Q=VA where Q = air flow, cu ft per min V -- velocity, ft per min A -- area of the hood face, sq ft . (2) Outside an unobstructed hood Horizontal: V 6 0 0 0 --7-- d0A <r + 1 where V = air velocity, ft per min a = specific gravity of the material p = air density = 10 V (X 2+ 0.1 A) d = diameter of the largest particle to be moved, in. where Q, V , and A are as in ( 1) X = distance from face of hood to source of contamina tion, ft. (3) A chip trap removes large particles close to the hood and serves to reduce the required air velocity. Objections to chip traps are the pressure-loss introduced, the fact that all the dust is not brought to a central point of collection, and the traps re Where the hood lies on a flat surface, the value of Q to pro quire frequent dumping. duce a given value of V is reduced 25 per cent from the calcu lated value. An equal reduction is permitted when a flange is METHOD OR PROPORTIONING PIPE SIZES added to the face of the hood. Two basic factors are: ( 1) Area at any section should not (3) The air flow into a hood over a tank or table is given by exceed QJV, where Q is the rate of air flow in cu ft per min past Dallavalle's equation = 1.4 PD V the section, and V is the minimum transporting velocity- in ft per .min; (2) the pressure loss produced in any branch line should equal th at created in th at part of the system which lies where P = perimeter of the hood, ft upstream of the branch when the proper rate of air flow exists D = distance from the edge of hood to the edge of the in each. The rate of air flow into any hood should not depart surface over which it is suspended, ft from the estimated value by more than =*=25 per cent. 112 M echanical Engineering The calculation of pressure losses involves no unusual steps and employs standard formulas and charts. Actual measure ment of the resistance is often desirable in the case of special fittings. It is sometimes not practicable to select pipe sizes exact enough to insure the requirements of both (1) and (2). In such cases, determine the size required under ( l ) and provide suit able variable resistances which are adjusted until the required distribution of flow is obtained. ALLOWANCE FOR FUTURE EXPANSION No additions to an existing system should be permitted which throw the distribution of flow out of balance by more than the =*=25 per cent variation allowed in pipe design. Failure to ob serve this important requirement has resulted in overloading many efficient exhaust systems. New pipe connections are best made at a point in the main pipe downstream of all branch connections and as near the air-cleaning plant as possible. In certain cases, notably when expansion is contemplated soon, it may be desirable to design the piping and fan for the ultimate system, only the needed part of which is built, and to provide orifices in th e ends of blanked-off pipe lines of sufficient capacity to admit as much air as w ill be handled by the future additions, thus maintaining the required velocity of transportation. PLANT LAYOUT Processes to be connected to one system should be located close together and w ith as much symmetry as possible about a center. The purpose of this is to permit the use of the shortest length of pipe and minimum number of bends, and to simplify the adjustment of pipe sizes for the proper proportioning of air flow from the various hoods. The plant layout should be arranged to permit the locating of exhaust piping so as ( 1) not to interfere w ith the operation of cranes, elevators, and trucks; ( 2) to allow ready access to the piping for inspection, cleaning, and repairs; and (3) to provide maximum protection of the piping from external damage. AIR-CLEANING EQUIPMENT Air cleaning is required for several reasons: CO To prevent the creation of a nuisance or hazard in the area around the out let; (2) to prevent the recontamination of plant air from the outside; and (3) to permit recirculation of the air which is discharged from the exhaust system in the plant; this is necessary in deep mines and is also often desirable in fac tories to conserve heat. Air-cleaning requirements vary w ith local conditions, from the most rigid in the case of complete recirculation, to a mini mum for an isolated plant from which the exhaust air can be discharged w ithout danger of recontamination. Operating characteristics of air-cleaning equipment shall be such as to give steady and continuous operation during a prac tical working period and thus not to require cleaning until the end of the w ork shift. There shall be no serious change in efficiency w ith use. Means must be provided for the disposal of collected material w ithout exposing the workmen to a hazard. The concentration of polluting material in the discharge air should be measured by a standard technic and should not exceed a previously established level; D ISC H A R G E STACK The simplest means of disposal is through a high stack. Dilution and favorable wind currents serve to reduce the con centration to a safe level. The nature and concentration of the escaping material and local meteorological conditions, such as down-draft winds and eddies around buildings, must be care fully considered, since these determine the practicability of this method of disposal. Dust particles large enough to settle out at once must be removed before reaching the stack, if a nuisance in the immediate neighborhood is to be avoided. PRIMARY DUST SEPARATORS Gravitational settlement chambers, cyclones, and simple inertial chambers serve to remove relatively large particles of dust, but cannot be depended upon to take out the minute par ticles of hygienic interest. They may be employed for two purposes: ( 1) To prevent the development of a nuisance from settling dust in the discharge area; (2) to relieve the load on dust filters in a two-stage cleaning plant. DUST FILTERS Properly designed cloth dust filters, when not overloaded, are capable of reducing the dust concentration in the filtered air to a level well within the safe limits of dustiness. Important factors contributing to unsatisfactory filter operations are over loading, improper cleaning, and lack of maintenance. Manufacturers of equipment must know the nature and par ticle size of the dust to be handled and the load of dust per cubic foot of air, as well as the rate of air flow. COLLECTION OF GASES AND VAPORS Gases and vapors are separated from air by physical adsorp tion and chemical combination and the proper method of treat ment must be determined for every gas to be collected. SOURCE OF SUCTION Fan and motor capacity are determined by (1) total rate of air flow , and (2) overall resistance of the system. The total rate of air flow Q equals the sum of the rates for the various hoods. Ten per cent may be added for leakage, although this should be unnecessary with well-constructed piping. The total pressure loss equals the sum of the losses due to (1) en trance into the hoods; (2) friction in most resistant branch; (3) friction in main exhaust pipe, including bends; and (4) air cleaning plant, including losses at entrance and discharge as well as within the plant. In order to get the static suction at the entrance to the fan it is necessary to add the velocity head in the pipe line to this sum. In general no special care is taken to convert velocity head into static pressure at transition sections, and it is best, therefore, to add for this purpose the head corresponding to the maximum velocity in the system. This usually occurs at the hood throat and is included in the static-suction reading at this point. Further addition of the resistance on the discharge side of the fan is necessary to give the combined suction and pressure against which the fan must operate. This value may or may not be equivalent to the static-pressure value employed in fan-capacity tables, depending upon how these are made up. Adequate provision must be made for the entrance of air into the building to replace that which is removed by the exhaust system. Inlets should be arranged and located so th at the workers are not subjected to harmful drafts. Fans handling inflammable vapors and explosive dusts must con form to regulations such as those which are incorporated in A.S.A. Code Z-33-1935- Fans on systems handling abrasive dusts should be located on the clean-air side of the dust filter to avoid wear. Fans han dling corrosive materials must be constructed of suitable resis tant material. February, 1936 CONSTRUCTION AND MAINTENANCE Details of construction are dictated in part by local condi tions, such as exposure to corrosive substances, abrasive dusts, and weather. Methods of construction should be governed to a greater extent by the question of subsequent maintenance than bv initial cost. As an engineering structure, an exhaust system should command as much care in its operation and maintenance as any other p art of th e plant equipment. The use of light con struction and improper protection of the system are not con ducive to this end. Modern methods of welding make possible the economical use of welded pipe and fittings in many places instead of lighter sheet-metal construction. Whenever possible, the manufacturer of plant machinery should incorporate the exhaust hoods in th e design of the ma chines. Consideration of the problem of exhaust ventilation before the machine is built will result, in m ost cases, in a more satisfactory solution than is given by the compromise that must be adopted when the hood is added to the finished ma chine. OPERATION A N D M AINTENANCE OP EXHAUST SYSTEMS Responsibility for the operation and maintenance of an ex haust system should be placed in the hands of one man. His duties should include: (1) Routine inspection and the repair or replacement of worn or damaged parts; ( 2) proper maintenance of the fan and m otor and other moving p arts; (3) operation of the air-cleaning equipment in accordance w ith the instructions of the designing engineer and the manufacturer of the equip ment; and (4) instruction to the workers in th e proper use of the systemfor their maximum safety and comfort. MEASUREMENT OP AIR PLOW Development of th e rates of air flow through the various exhaust hoods equal to the estimated requirements employed in the original design carries no guarantee th a t the proper de gree of control will result, since these rates are only estimates. Routine measurement of air flow, however, does show whether 113 the system is operating in accordance with the original design and is therefore a valuable index of operation. The determina tion of static suction at the various hoods is helpful in this re spect, but in addition it is desirable to provide an air-flow meter in the main pipe to indicate the total flow. A pitot static tube may be used for this purpose. Its advantages are that it is sim ple to install and operate, and it introduces no pressure loss in the system. In a dust-control system it is troublesome be cause the pressure holes plug w ith dust. A venturi section in the main pipe provides a permanent meter w ithout great cost and does not introduce an excessive pressure loss when properly designed. TESTING EXHAUST SYSTEMS FOR EFFICIENCY OF OPERATION The measurement of the concentration of contaminating material in the plant atmosphere and in the discharge area of the exhaust system constitutes the basic means of determining the effectiveness of the control secured. Suitable methods of sampling and measurement must be employed and the results compared w ith certain pre-established standards of permissible concentration. Methods of analysis and allowable concentra tions have become sufficiently well-standardized to warrant their inclusion in the specifications for exhaust systems for many industrial processes. A few tests at the outset of plant operation cannot be relied upon, however, to give a true measure of control over a long period of time. It is essential to make certain that the design of the system is fundamentally sound, that the system is oper ated in accordance w ith the instructions of the designing engi neer and the manufacturer of the equipment, and, finally, that the system be properly maintained. In certain cases, conditions may warrant the installation of automatic recorders of concentration of the polluting material. Such instruments are available for certain kinds of dusts and for various gases. In other cases, routine measurement of con centration through the use of simple measuring instruments is to be recommended. Suitable measuring instruments are avail able for many industrial contaminants. PLANNING-THREE VIEWPOINTS By B. ALDEN THRESHER MASSACHUSETTS INSTITUTE OF TECHNOLOGY D ISCUSSION about the possibility and desirability of a planned society commonly proceeds on one of three different planes or levels: First, the engineering or physical level; second, the economic or value level; and third, the political or, more broadly, the social level. Three books selected from the large current literature of the subject illus trate these three planes: Loeb's "C hart of Plenty, " 1 Mrs. fact, are keys to the economic aspects of the problem, to which Mr. Loeb, in his preoccupation w ith the physical aspects, gives scant attention. The economic aspects, however, fo ra the main theme of Mrs. W ootton's analysis, to which we now turn. " plan or no pla n " W ootton's "Plan or No Plan, " 2 and Lippmann's " Method of Freedom." 3 This arrangement of titles corresponds roughly to the respective levels of analysis just mentioned, to an as cending order of complexity in the problems dealt with, to a descending order of naivete in the manner of treatment, and to an ascending order of conservatism in estimating the poten tialities of planning. " Plan or No Plan" is an able comparative study of the un planned capitalist economy and the Soviet planned economy. The strength and weakness of each is appraised, and- the methods by which each can meet the problems of balance and adjustment are subjected to economic analysis. Mrs. Wootton, so to speak, begins where Mr. Loeb leaves off, and grapples with the tough issues which he so airily glosses over, such as " n a t io n a l su r v e y o f p o t e n t ia l p r o d u c t ca pa city " On the physical level, the questions to be answered are: How much can we produce? and, How much should we con sume? To answer these questions, Mr. Loeb and his associates in the "National Survey of Potential Product Capacity" have made an elaborate statistical survey of productive capacity, compared w ith actual 1929 output and w ith an estimate of consumption needs. The information has been ingeniously sum marized into a " flow sheet" which takes some account of the complexities of production by stages, w ith finished goods com ing forward into use at points whose remoteness from the extractive industries varies widely. To focus the argument, let us assume th at the statistical estimates are correct. They indicate, briefly, a potential capacity, w ith existing plant and manpower, to turn out a national dividend valued at 135 billion dollars, or $4400 per family, an increase of about 40 per cent over the 1929 figure. Thus far the author is on firm ground. The physical capacity is there. Nor can we disagree w ith the conclusion that our exist ing system results in much restriction of output in the interest of maintaining monopoly price. The solution offered, however, is the uncritical one of distributing "purchasing power," together w ith " central control" of the production of "nonscarce" goods. It is, of course, clear th a t the defect in our economy is not primarily technical, but concerns those intangibles of mutual balance, organization, and incentive which are essential to the smooth operation of the economic process. It is not to be ex pected th at distribution of purchasing power will serve to redress this balance. To the extent th at it does not, the effect w ill be simply an uneven rise in prices. The author fails to realize, moreover, that scarcity is entirely a relative term, and th a t the problems of central control may well exceed in com plexity those which now confront us. These two terms, in the nature of scarcity, the problem of balance, and the tech nique of central control. Mr. Loeb sees the production prob lem in terms of " bottlenecks" of physical capacity. Get rid of these, or make adequate allowance for them, and all will be well. Mrs. Wootton, however, is more realistic as well as more subtle. She apprehends the opposing pull of comparative costs and sees the economic process as one of continual, mutual adj ustment of these costs to each other and to the utility of one more or one less unit of product. The cost of producing bread depends not only on how much bread is or " ought" to be produced, but on how many shoes or tacks or false teeth arc produced. Mr. Loeb, w ith his bottlenecks, is on safe ground as long as he hews to the line of a given pattern of consumption and a scheme of production defined in advance. But this is only the beginning of the problem of economic control, i.e., to obtain continuous mutual adjustment of the system to internal changes. The old dilemma of value remains: How much of one thing is equivalent to a unit of something else? How can we equate one man's pleasure w ith another man's toil; the satisfaction of the consumer to the effort of the worker? The price system provides machinery for this comparison, albeit defective machinery. The controlled system substitutes an authoritative judgment which must make its own assumptions about what people want or what is good for them. Mrs. Wootton works over the ground of this analysis with care and no little skill. She checks her conclusions against actual results under both systems. When, in consequence, she finds some balance of evidence in favor of planning (not, of course, the same thing as communism), we feel that she has at least passed beyond wishful, and into analytical, thinking. The " dollar vote" mechanism performs the service of equating work and pleasure, costs and prices, subject to two leading defects. First, the machinery of competitive markets is im perfect, so that, for example, a low money wage may throw on 1 "The Chart of Plenty," by Harold Loeb and associates, Viking relatives or on the state the burden of later supporting a broken- Press, New York, N. Y., 1935, 180 pp., $2.50. down worker. Price does not include all "real" costs. Sec- 2 "Plan or No Plan," by Barbara Wootton, Farrar & Rinehart, Inc.,opd, because incomes are unequal, a large money bid for a New York, N. Y., 1935, 360 pp., $1.60. product or service does not necessarily reflect a higher real 3 "The Method of Freedom,'' by Walter Lippmann, The Macmillan, Co., New York, N. Y., 1934, 117 pp., $1-50. " want" or " need" on the part of the bidder. Out of these two Eleventh of a series of reviews of current economic publications type situations, plus the periodical breakdowns of depression, affecting engineering, prepared by members of the Department of one can develop the entire case against individualism. Economics and Social Science, Massachusetts Institute of Technology, at the request and under the sponsorship of the Management Division The case against control may be exemplified also by two type of T h e A m erican Society of M echanical E n g in ee r s. situations. The first is the well-known fact that the first Five 114 February, 1936 115 Year Plan pushed heavy industry for future use at a pace which half starved the consumer-goods industries. Under the con trol of a " market" rate of interest, a different and more hu mane balance would have been struck between " some goods now and more goods later." For our second case, consider a certain Soviet orphans' home in which the children, on half time work, turned out simple electrical fittings. The director explained w ith pride th a t the home was completely selfsupporting. It developed, however, that a monopoly existed and a high price was charged to make this possible. Buyers of these fittings were, in effect, assessed the cost of running the children's home. Here, then, is a converse case of unbalance. Where the competitive economy may exclude certain costs from the market price, the controlled economy may load the price irrationally w ith costs which should logically be borne in a different manner. If we translate these cases into other terms and multiply them, we get a picture in which neither plan nor no -plan gives more than the roughest possible adjustment of production to wants. But, as our author points out: "If the planners make mistakes exactly like the mistakes of capitalist producers, and embark on lines of production which are expected to be profit able but find a disappointing market, they are by no means obliged to shut up shop unless they wish. A mistake is, of course, still a mistake, but there is no necessity for it to reveal itself in the particular form of unemployment and unused plant. Instead, goods can be offered below cost to a public which does not consider them w orth the money spent in making them, and the mistake is paid for in that way.'' Hence there may be a less direct connection between mistaken estimates and unem ployment in such a system than in ours. The planned economy, like the doctor, can bury its mistakes, or at least absorb them in ways which make them less obvious. Or, to change the metaphor, its mistakes, instead of breaking out in local boils on the body politic, can be reabsorbed and the virulence of the poison distributed more widely and imperceptibly. The foregoing remarks are too compressed to do justice to Mrs. W ootton's book. It is an analysis primarily on the economic plane, and colored perhaps by the viewpoint of an English writer thinking in terms of a compact and homogene ous country. The terrific social and political upheavals that have accompanied the institution of planning in Russia, right down through the famine of 1933 and the collectivization of the peasants, are passed over lightly. It is the virtue of Mr. Lippmann's little book th a t it takes account of the political accompaniments of such methods of assuring physical pro ductivity and of compelling economic balance. Mr. Loeb and his engineers hail w ith visionary rapture the planned state; Mrs. Wootton admits it grudgingly. Mr. Lippmann rejects it, except in a mild and tentative form. ` `t h e m e t h o d o f f r e e d o m " The analysis in "The Method of Freedom" is more sophisti cated and wiser than these others, because by implication it includes their arguments, and then goes beyond them. As Lippmann .points out, the real choice is not laissez-faire versus collectivism, but solely what kind of collectivism. And here the main contrast is between the sort of directed economy which the previous authors come to, i.e., one subject to thorough going central control, and, on the other hand, w hat Lippmann calls a compensated economy, or the method of free collec tivism. " The military pattern is the basic pattern of any directed social order. . . . In an economy which is directed according to a plan and for definite national objectives, the official must be superior to the citizen, and the hierarchy of officials who compose the government must be absolute as against the individual. . . . The law is the will of the rulers above him. They are subject to no law. There are no customs, contracts, constitutions, or ancient usages which limit them. His rulers are controlled only by their own judgment and by the scope of their own power." The method of free collectivism, per contra, arises naturally out of the long series of government measures which have grown up to regulate and control capitalist industry in many countries. While it is acknowledged th at the state has an ob ligation to protect the standard of life and insure the smooth running of the economy as a whole, there is, nevertheless, free dom of individual initiative within wide limits. But in the compensated economy of Mr. Lippman, the state must go beyond the mere prevention of abuses. I t must throw its weight now this way, now that, like live ballast in a sail boat, to com pensate for the cumulative errors which mass emotion, mass buying, and mass investment bring about:. Such a system is not an abstract theory, but is built out of elements already in practical use. Such compensatory devices are, for example, the control of credit and currency by central banks; the long-range planning of public works; discriminatory taxation, repressing here, en couraging there; control of the capital market in ways illus trated, for example, by our recent securities legislation. All these devices are natural outgrowths of institutions to which we are already attuned, and which accord with the genius of our people. On the other hand, it has never been demon strated th at a system of thoroughgoing control can coexist with political freedom. Existing examples point to the re verse. Addressing himself to the practical problems of operating such compensating devices in a representative democracy, Mr. Lippmann turns up the important principle that the people who are applying the compensatory forces must usually be working directly against immediate popular opinion and against pressure groups representing special interests. The in ability of the modem democratic state to administer policies that require independence, foresight, and devotion to general, not local, interests, he traces to the fact that legislatures have acquired the initiative in fiscal matters. Historically and rightly, he argues, the power of the purse has meant the power of the assembly to refuse revenues, and grant them " on terms." But in modem states, the legislature, instead of telling the executive w hat he may spend, tells him what he must spend; not merely how much he must tax, but what he must tax. An indispensable condition of free collectivism, then, is an execu tive initiative in fiscal matters, w ith the legislative branch serving only as a check and balance. Such a free collectivism " as indicated in the policies of the English-speaking countries during the present crisis is the method of liberty in the twentieth century as laissez-faire was its method in the nineteenth." Its special concern is' to bring as many as possible into the "middle condition" which Aris totle saw as the great source of stability in the state. "Free men with vested rights in their own living: Men like these alone, and not employees of the state or the disinherited who today walk the streets and arc at home nowhere, can constitute a free society." The foregoing brief and sketchy characterization of these three books does real justice to none of them. This the reader can remedy by perusing them for himself. The aim of the re viewer has been rather to characterize each and to place it in a larger setting. Study of the three books, in the order named, will go far toward providing the elements of a hu mane and liberal education in this much-abused aspect of political economy. ENGINEERING PROGRESS AERONAUTICAL ENGINEERING Automobile Engines for Aircraft THE author believes that the activi ties of the Bureau of Air Commerce in the direction of conversion of auto mobile engines for aircraft use is un fortunate. He considers the m atter pri marily from the point of view of weight and shows how much heavier automobile engines are than aircraft engines. More over, an automobile engine is mostly driven at half throttle or less, while an aircraft engine operates some 75 per cent to full throttle most of the time. Parts of automobile engines used for aircraft are widely accessible, but skilled aircraft repair mechanics are not. The author expresses a doubt whether an automobile engine compares favorably w ith the modern aircraft engine in respect to dependability. The cost of the former is lower, which is largely due to mass production, and the author doubts whether an engine designed specifically for light aircraft can be manufactured and sold at prices comparable to auto mobile engines. The article is highly controversial and cannot be abstracted in full. A suggestion is made that an en gine be developed which is basically suitable for rear-end-mounting on auto mobiles as well as for aircraft, the matter of weight being a serious con sideration in both classes. (Glenn D. Angle in Aero Digest, vol. 27, no. 4, October, 1935, pp- 23 and 102) APPLIED MECHANICS Surge in Springs THE author discusses the surge condi tion generally and points out the possibilities of trouble from resonance. To study this phenomenon special appara tus was set up in the laboratory of the Department of Mechanical Engineering of the Pennsylvania State College, de scribed in detail in the original article. These investigations have shown that surge is an important factor in tHe be havior of springs in many applications, even in those of relatively low speed. By test it is possible to determine the speed of the cam and the initial tension which will reduce the effect of surge in any given spring to a minimum. Avail able formulas for determining the natural period of such springs do not give results sufficiently close to the actual to be of much use. The author recommends the Simmons formula to be used as it approximates the results of Love, but points out th at the theoretical formulas unfavorably give results from 10 to 15 per cent higher than those shown in the actual spring. (C . H . Kent, Professor of Mechanical Engineer ing, Pennsylvania State College, in Machine Design, vol. 7, no. 10, October, 1935, pp. 37-39) CORROSION The Duraspray Rust-Proofing Process THIS process consists primarily in ap plying first a priming coat of red-lead paint, then dry-spraying on to the wet surface of this coat a finely divided metal lic powder consisting of specially pre pared zinc dust containing a certain pro portion of aluminum, and finally apply ing a finishing coat of paint of a character and color to suit the particular job. The priming coat is of special undisclosed character. The metallic-powder spray ing equipment is coupled by means of flexible hose to an air compressor de livering 21 cu ft of air per min at 40 lb per sq in. pressure. (Engineering, vol. 140, no. 3641, Oct. 25,1935, p. 456) ELECTRICAL ENGINEERING High-Frequency Current for High-Speed Motors THE use of high-frequency current is attributed to the desire to obtain higher speeds than those obtainable w ith current of normal frequency. W ith 60 cycles, for example, maximum motor speed obtainable is th at of a two-pole unit, or 3600 rpm. High-frequency mo tors are generally employed when it is de sired to avoid the necessity of intermedi ate transmission such as gear, belt, or chain drive. One of the largest fields o f application is in woodworking. Two methods are available for raising the frequency above th at of the supply line; by motor generator and by fre 116 quency converter. A motor generator employed for frequency changing requires a generator having a sufficient num ber of poles to produce the desired frequency when running at the speed of the driving motor. The frequency converter con sists of a motor-driven induction genera tor similar to a wound-rotor motor. Motor-generator sets are less commonly used than frequency converters because of the latter's higher cost and necessity of attendance, but frequency converters have the advantage that the high-frequency output is independent of the voltage fluctuations in the supply lines. Further details about this kind of apparatus, in cluding combined autotransformer and frequency converter, will be found in the original article. (Geo. H. Hall, Cons. Engr., in Electrical World, vol. 105, no. 21, Oct. 12, 1935, pp. 34-35, and 90-91, illustrated) ENGINEERING MATERIALS Plaskon PLASKON was originally developed at the Mellon Institute of Indus trial Research at the University of P itts burgh on behalf of the Toledo Scale Co. and is now being made at the Toledo Synthetic Products, Inc., at Toledo, Ohio. It is of the group of urea com pounds. It is a heat-hardening plastic for hot-welding, compounded from ni trogenous resins, fillers, pigments, mold lubricants, and softening agents. The original article states in some detail the method of making parts from this mate rial and the precautions in molding. The moldings can be used as they come from the mold or after a light buffingThey can be tap-controlled or otherwise machined. Plaskon moldings can be joined to one another by being cemented, by pressure fits, and by rivets or screws. The control of molding conditions, the making of molds, and the molding of a large casing are described in the original article. The physical properties of plaskon may be briefly noted as follows: Specific'; gravity, about 1 .5 ; flexural strength (modulus of rupture), 10,000 to 20,000 lb per sq in.; compressive stren g th ,' 25,000 to 35,000 lb per sq in.; tensile February, 1936 117 strenerh, 8000 to 13,000 lb per sq in.; hardness on the mineral scale, 3 to 3.5; hardness on the scleroscope scale, 80 to 95The list of applications where Plaskon can be employed usefully and for which h is not recommended are given in the original article. (Machinery, New York, vol. 42, no. 3, November, 1935, pp. 165?-174, illustrated) Subcutaneous Effects During the Scaling of Steel THE author deals w ith minor changes of structure or composition of articles during heat-treatment, which may affect the surface finish. He deals primarily with changes which have been observed during the oxidation of various steels in the laboratory. Some of these, how ever, may prove to be of industrial interest. The experiments made by him show that when steels containing certain elements in contact w ith the scale are heated, globules and spots are formed within the steel. It was established that the presence of oxygen is necessary for the formation of these globules and spots, and this oxygen is supplied by the scale in the cavity and obtained during the initial stages from such oxides as Fe20 3 and Fe3C>4, and during subsequent changes from FeO which would cause the main effect. The character of the globules and spots differs according to the elements contained in the steel. Whenever scaling of an article occurs-- for instance, during heat-treatment-- particularly if the surface oxidation is slow, some formation of globules and spots is to be expected. Whether the affected area is removed by subsequent processes, such as pickling or machining, will depend, inter alia, on the extent of the affected area and the amount of metal removed. It would also appear th at the more oxidizable elements contained in the steel, the greater is the extent of precipitation and formation of globules and spots, so th at where a specially good surface is required the steel should contain a minimum of elements having a high affinity for oxygen--that is, any excess of deoxidizing agents, such as aluminum, should be at a minimum. Unless the affected area is removed completely, the effects of the phenome non on a steel' intended to be fatigueresisting may be to initiate surface cracks. In tin-plate manufacture, while the affected area, if any, must be extremely thin, owing to the rolling processes subsequent to its formation, its possible presence cannot be entirely disregarded. It is conceivable that its effect would be to increase the possi bility of porosity, particularly' if the sheet is to be used for deep stamping. The surface of the sheet containing the nonmetallic particles might not be able to withstand the stressing occurring in the process, and minute incipient cracks m ight be formed at the surface of the steel. The support of the tin coating would not then be continuous, so increas ing the liability to failure and the result ing porosity of the coating. (Engineer ing, vol. 160, no. 3638, Oct. 4, 1935, pp. 378-379, illustrated) Beryllium D ETAILS of the manufacture of beryl lium and a brief statement of the properties of the metal itself are con tained in this article, and there is a table of the physical properties and technical characteristics of beryllium copper w ith 2.5 per cent beryllium, beryllium copper w ith 1.9 per cent Be, and beryllium contracid w ith 0.75 per cent beryllium. It is stated th at the price of raw beryllium in Hamburg is l for each per cent of BeO per ton. It is said, however, that the present price is much lower than the one which prevailed only a few years ago. The consumption of beryllium in Ger many at present is between 500 and 1000 kg per year. Much greater amounts are consumed in the United States, particu larly in the manufacture of beryllium bronze. (W. Hessenbruch in Metall und Er%, vol. 3 2 , no. 11, June, 1935, pp. 234237) FUELS AND FIRING Motor Spirit From Tar THE Department of Scientific and In dustrial Research in England pub lished two reports (Technical Papers Nos. 40 and 41) dealing w ith the conver sion of tars into motor spirit by means of hydrogenation cracking. According to these reports a wide variety of catalysts was tried. The general conclusion is th a t a mixture, of commercial molybdic acid and sulphur was the most effective substance. Three groups of tars were tried as raw materials: From different low-temperature carbonization processes; from five coals of different types carbon ized in vertical cast-iron retorts; and from four coals carbonized at rather high temperatures in narrow, vertical, brick retorts. The tars of the third class were definitely more difficult to treat. (The Steam Engines, vol. 4, no. 12, September, 1935, pp- 503-504) INTERNAL-COMBUSTION ENGINEERING Supercharging A SYMPOSIUM of four papers on supercharging dealing respectively w ith aircraft engines, marine oil en gines, touring-car engines, and super charging generally is presented. In discussing the application of super charging to aircraft engines, A. H. R. Fedden states that it is true to say that it would be impossible to produce the large modern aircraft engines with their present power-weight ratio without the aid of supercharging, and the disposable load and maximum speed of aircraft would be most adversely affected by the increased weight, bulk, and drag entailed by the use of naturally aspirated engines of the same power as existing super charged types. For instance, a singleseater fighter driven by an engine giving 700 hp at ground level might have a top speed of 200 mph at an altitude of 15,000 ft, but w ith an engine giving 700 hp at 15,000 ft it would show an increase in top speed to 248 mph, because the engine rated at 700 hp at ground level would give only about 420 hp at 15,000 ft. The extent to which the supercharging can be carried out on any engine depends upon a number of factors, such as the oc tane number of the fuel, piston compres sion ratio, fuel-air mixture strength, mix ture temperature, ignition advance, and the shape and size. of the combustion chamber. It can be seen, therefore, that the purpose for which the engine is to be used must be taken into consideration, and while one can say generally that for the same increase in overall compression ratio, more power can be obtained by in crease in supercharging pressure rather than by increase of piston compression ratio, such a division of overall com pression ratio adversely affects the fuel consumption, which is an extremely important point on engines employed in long-range aircraft. It has been clearly proved in the past that it is unwise to endeavor to increase by boosting at ground level the power of an engine having inadequate breath ing organs, as such a procedure inevitably brings trouble in its train. To obtain satisfactory and efficient supercharging the engine should have the largest possible valve and port areas. As an example of what can be done w ith an air-cooled aircraft engine boosted at ground level, the Bristol Company has recently completed an Air Ministry type test on the "Pegasus X" engine, which gives 920 hp at ground level for take-off, and 875 hp at 6000 ft, the net 118 M echanical Engineering dry weight of this engine being only 995 lb. As regards the mechanism of super charging, the mechanically driven centri fugal-fan type is generally preferred. The Bristol Company has recently com pleted an exhaustive research for the Air M inistry on geared centrifugal blowers, which covered some fifteen months' work and included an investigation into differ ent types, diameters, and clearances of impellers and diffusers and impeller bear ings. From this research it has been possible to obtain a fair idea of the possibilities of this type of blower, and the detail improvements which may be expected. Where it is necessary to main tain considerable power for take-off and climb, it is not thought reasonable to use a single-stage blower of centrifugal type w ith a compression ratio of more than 1.85/1 (giving a rated altitude of 15,000 ft), owing to the power losses in the blower when running throttled on the ground and the power limita tions entailed by mixture temperature w ith the available standard fuels. The exhaust turbo-compressor type has so far proved difficult to arrange neatly on a radial engine, but can be better accommodated on the in-line type. In the author's opinion the ex haust turbo-compressor has been unduly condemned, and it has been shown that this type of turbine provides an efficient silencing and flame-damping system for the engine. MARINE OIL ENGINES In discussing supercharging in connec tion w ith marine oil engines Sterry B. Freeman says that at the present time in marine work a number of supercharged engines working on the four-stroke cycle are run at mean indicated pressures of 134 lb per sq in., which is approximately 50 per cent higher than th a t employed by induction or nonsupercharged engines. The heat given up to the cylinder cooling w ater is not increased by the additional amount of fuel burned per stroke, consequently the heat stresses in the metal are not increased; also the effect of the better scavenging and cooling supplied by the supercharged air helps to keep down the temperature of the metal. It has been general experience that the best combustion and the greatest econ omy of fuel have been attained when scavenging has been most complete, and this is not the least part of the benefit of supercharging. TOURING-CAR ENGINES The touring-car engine situation was discussed by L. E. W. Pomeroy. Trans lating the " controlled" horsepower gain into terms of road performance, it is neces sary to realize that the percentage of in crease in surplus horsepower is far greater than that of net horsepower, " surplus" horsepower being defined as the margin available at any speed above th at re quired to overcome wind and tractive re sistance, Thus, while the net horse power may be increased by 50 per cent at 45 mph, there will be 100 per cent gain in surplus horsepower which will rise to 150 per cent at 50 mph, and to infinity at 60 mph, taking as an example a 10-hp saloon car w ith this speed as its maxi mum. These impressive figures are realized because supercharging is fundamentally the only way an engine can be given an increased effective capacity w ithout en larging the overall dimensions, or the windage of the car, and w ith an increase in weight of under 2 per cent. As a re sult, it is common for the acceleration times either on top gear or with the use of the gears to be halved, and for the top-gear speeds up main road hills to be increased from, say, 40 to 60 mph. With quite small supercharged engines, a car can be produced w ith a top-gear perform ance approaching that of a large luxury vehicle and high average road speeds can be attained in safety and without great mental or physical effort. The development of the supercharged car has been delayed by the difficulty of producing a suitable machine having no highly loaded parts, but in order to secure good volumetric efficiency it must be manufactured w ith the utmost care and by reason of slight distortions of the large cam-shaped rotors, often seems to demand hand-fitting, which materially raises production costs. Another factor tending to costliness is that in order to achieve silence, a fine clearance must be maintained between the rotors them selves and between the rotors and the case. The former clearance depends not only on the machining of the rotors, but also on that of the gears which maintain them in relative position. Production engigineers are fully cognizant of the difficul ties of making gears silent, and if the rotors are regarded as two large gear wheels, it will be seen that the problem is really that of matching two sets of gears to run completely silently, a prob lem which, if it is not insuperable, is at least one which presents considerable difficulty. The merits of the Roots blower are its reliability and the fact that all bear ings requiring lubrication are outside the pumping chamber. POINTS AGAINST SUPERCHARGING A position against supercharging was taken by R. H. Ricardo, who said that it has frequently been claimed that by means of supercharging, it is possible to gain a large increase in output and in fuel economy. It is not possible to make good both claims. If the addi tional air is to be used for anything like a proportional increase in power, and if the maximum pressure is limited as it must be in practice, then the effect is to curtail the ratio of expansion, and there fore to lower somewhat the efficiency. If it is used to increase the air-fuel ratio, then it w ill provide an improvement in efficiency by increasing somewhat the ratio of expansion, but not in power output. Nature offers an unlimited supply of air at a pressure of 15 lb per sq in.; we are not bound to take what is offered, but we must be prepared to pay extra if we decline to accept what is available. We must pay for it either by the power required to drive the blower mechani cally or by accepting the inconveniences and limitations of an exhaust-driven blower. The author apparently can see some reasons for using supercharging for in creasing the power of an existing engine but not (except in certain special applica tions) for installing it in an engine newly designed. Among other things he states the following: One is often told to look at the exhaust temperature of a super charged engine and note the low reading, w ith its implication of high thermal efficiency. Such a reading is bound to be low, for the hot exhaust gases are diluted with cold scavenge air, but that does not mean that the efficiency is in creased, or that the cycle is any cooler. One is almost tempted to suggest that scavenging is not so much an advantage for the engine as a positive necessity for the turbo-blower so that its temperature may be kept within bounds. One is told, too, to look at the reduced heat flow from the cylinder head. By far the greater part of the heat which passes into the cylinder head is given up by the outgoing gases in the exhaust port and this is also greatly reduced by dilution with cool air. One can always-cool his soup by blowing it, but that does not economize the cooking. When one looks at the piston temperatures, one finds rather a different story, and it must be remembered that the piston tempera tures are the most truthful indication of the efficiency, and the piston the most susceptible part of any engine. (Sym posium before the Internal-Combustion F e b r u a r y , 1936 119 gngjne Group, Institution of Mechanical Engineers Proceedings, vol. 129, 1935, p p .197-217) Scavenging of Two-Stroke-Cycle Carburetor Engines THE conventional method of scaveng ing small high-speed two-strokecycle carburetor engines is shown at the left of/Fig- ! This is said not to have proved to be entirely satisfactory, and a new method of scavenging has been developed by Schnurle shown at the right of Fig. 1.` 1 lb n o . 1 DIAGRAMMATIC PRESENTATION OP THE CONVENTIONAL AND N EW METHODS OP SCAVENGING TW O - STROKE - CYCLE HIG H SPEED CARBURETOR ENGINES ([Quirstromspulung = crosswise scavenging; Umkehrspulung = reverse scavenging; Ausfuff = exhaust; Einlass = admission; Scbnitt = section.) The characteristic feature of this new method of scavenging is the absence of a baffle projection on the top of the piston, giving the piston a clean arch top. The gases are handled by means of slots so as to produce w hat is claimed to be thorough scavenging of the cylinder w ith a minimum o f'g as losses. It is claimed that the combustion chamber is more efficient w ith the new piston. To w hat extent the improve ment in operation is due to the shape of the piston, or to the new method of scavenging, has not yet been completely established. It is claimed, however, on the basis of tests at the Institute of Internal Combustion Engineering that there is an improvement. It is also claimed that it has been found that any rise of temperature in the charge before the closing of the exhaust slot affects the "quantitative" scavenging efficiency in the same manner as if the scavenging medium were used to a greater extent. It is further claimed that of the improvement in efficiency about 65 per cent may be ascribed directly to the new scavenging process and 35 per cent to the higher compression ratio made pos sible by the shape of the piston. Any lowering of temperature in the scaveng ing-pump chamber not only improves the output but .correspondingly raises the quantitative efficiency of scavenging. (Klaus Karde in Automobiltechnische Zeitschrift, vol. 38, no. 15, September 10,1935, pp. 421-426,8 figs.) W olf Airless-Injection Engine for Tour ing Cars THIS engine has a piston stroke of 120.6 mm and a cylinder bore of 85 mm, giving a swept volume of 2.75 liters. Recently a number of private owners of cars of different makes have substituted it for their original engines. Trials in Russia are briefly reported here. The original article gives power and torque curves. The upper curves in each case FIG. 2 POWER AND TORQUE CURVES OF A WOLF AIRLESS-INJECTION ENGINE FOR MO TOR VEHICLES have been obtained from the engine fitted to a racing car and the lower from a com mercial-vehicle engine. A description of the design of the engine w ill be found in Engineering, voi. 136, 1933, p. 583. (En gineering, vol. 140, no. 3640, Oct. 18, 1935, pp. 426-427, 5 figs.) Influence of Benzol Additions to Gasoline Alcohol THE author enumerates the advantages of benzol additions, such as in creased resistance to pinking. These are well known and therefore not re ported here. The tests were performed w i t h m ix tu re s of v a rio u s proportions and w ith various nozzles. Only the general conclusions are stated here. Mixtures of 5 per cent of benzol did not seem to be greatly affected by the sizes of nozzles selected. A table in the original article gives data as to engine output and fuel consumption. Where ten per cent of benzol has been tried w ith some nozzles, better performance at speeds above 1200 rpm was found than with straight alcohol gasoline. With some other nozzles the performance fell off at speeds above 2000 rpm. It was found generally that w ith certain nozzles the consumption of the mixture con taining benzol fell off w ith increase of speed, and were generally lower than that of the gasoline-alcohol mixture. With other nozzles the consumption fell off at first but at speeds above 2800 rpm began to increase. Apparently the dimensions of the air nozzle had a decid ing effect in this case. Data are given in the original article for cases of 20 per cent benzol and a mix ture of 20 per cent by volume of an hydrous alcohol, 30 per cent by volume of benzol, and 50 per cent by volume of gasoline, as well as a mixture containing 25 per cent by volume of absolute alco hol, 30 per cent by volume of benzol, and 45 per cent by volume of gasoline. The consumption in both cases was ap parently less than th at of straight gaso line-alcohol mixtures for about the same power output, although the second of these two mixtures did not turn out quite so well as the first. (Prof. J. Formanek, Automobiltechnische Zeitschrijt, vol. 38, no. 16, August 23, 1935, pp. 409-413,7 figs.) Bituminous-Coal T ar as Fuel in High-Speed Diesel Engines ONE of the main reasons why this investigation was undertaken is because this fuel is a native German product and if successful could be used instead of imported fuels. The matter of effect of fuel on the process of com bustion generally is discussed somewhat briefly. Tests on, starting have shown that it is impossible to start even a warm engine w ith bituminous-coal-tar oil after only a few seconds of standing still without some auxiliary starting device. This can be done w ith a hot spot, however, and methods of installation are discussed in detail. The conclusion to which the author comes is that it is necessary in order to ignite heavy fuels to maintain high temperatures in the combustion chamber of a Diesel engine, and that this must be accomplished by some means which would not have any deleterious effect on the quality of the combustion which then takes place. A process, which, it is claimed, does this very thing, has been developed for V 120 M echanical Engineering precombustion-chamber machines and has been tried on three motors of various constructions. In this case the air flow ing through the precombustion chamber was preheated in a heat-storage device iocated at the point of maximum heat transfer. It is said that w ith this device bituminous-coal-tar oil, which is by far the most difficult to ignite of all other fuels of this class, could be burned in a satisfactory manner in high-speed pre combustion-chamber engines, (Dr. of Engrg. Karl Zinner, Zeitsckrift its Vertints dtufschtr Ingenieure, vol. 79, no. 44, Nov. 2,1935, pp. 1319-1326,15'figs.) Diesel Dredge "Jewett" THE Jewett Diesel dredge is an unusual combination of pipe-line dredge and large river towboat, the hull having some of the characteristics of each type of vessel. The result is a powerful suc tion dredge that is independent of tow boats and is able to move to any desired location under its own power. The dredge equipment consists of a centri fugal type of pump having a 22-in. suction line driven by a Busch-Sulzer six-cylinder Diesel engine rated 1600 bhp at 250 rpm. The engine is con nected w ith the dredge pump by means of a Farrel-Birmingham gearflex cou pling. The propelling machinery com prises two 750-hp Busch-Sulzer Diesels designed to operate at 250 rpm and drive cast-steel adjustable-speed propel lers having four blades. The equipment has a number of interesting features of which only a few can be mentioned here. The first is a 450-hp motor mounted on the dredging ladder and used for operating the cut ter head. This motor is connected through Farrel-Birmingham reduction gears to the cutter-head drive shaft. It is supplied w ith current from a 375-kw motor generator, and speed control is obtained by varying the field voltage of the generator. A large winch is mounted on the for ward end of the main deck and is used for raising and lowering the dredging ladder, and for hauling to port or starboard as required during dredging operations. The two hauling drums and the hoisting drums are operated by a single motor, in dependently controlled by means of brakes and clutches operated by pneu matic cylinders. These pneumatic cyl inders are operated from the dredging control room on the upper deck and air for the system is supplied from a lowpressure air system. This low-pressure air system includes a motor-driven twostage compressor which discharges to two tanks 30 in. in diameter and 5 ft long, the air being stored at 125 lb pressure. The control of the pressure in this system is entirely automatic, the compressor starting up when the pressure falls to 120 lb and stopping when the pressure reaches 130 lb. The winch motor is of 125 hp and drives the winch through a Farrel-Birmingham speed reducer. A 105-kw motor genera tor supplies current for this motor, and speed control is obtained by varying the generator field voltage. A completely equipped machine shop having all the machine tools required for ordinary maintenance work is installed. The water system is unusually complete and complicated but cannot be described here. To facilitate the handling of machinery parts in the course of main tenance and operating work complete hoisting facilities are provided. In order to make use of the heat avail able in the exhaust from the main dredg ing engine which w ill be in operation a large part of the time, an exhaust-gas boiler of the Clarkson type manufactured by the Electric Boat Company is to be in stalled. This boiler has a capacity of 815 lb of steam per hr at a pressure of 25 lb when the dredge-pump engine is operat ing at rated load. This boiler is ar ranged for burning oil fuel when no exhaust gases are available, and the oil firing system is entirely independent of the exhaust heating system. (Motorship, vol. 20, no. 11, November, 1935, pp. 416-418 and 424, illustrated) Dissociation of Combustion Gases and Its Influence on the Efficiency of Car buretor and Diesel Engines THIS is an extensive investigation, and only the part dealing w ith the dissociation of gases itself will be ab stracted here. SPECIFIC HEAT OF GASES Up to a few years ago specific heats of gases could be determined only by experi ment. The possibility of computing them from spectroscopic data was recog nized but not practicable. This resulted from the fact that only within the last few years, as a result of studies in the field of band spectra and the discovery of the Raman effect, has the necessary spec troscopic data become available, while the developments in atomic physics have given the theory of determination of spe cific heats a solid foundation. The deviation of the theoretical values from those determined experimentally was quite substantial at times in the past. Thus, the true specific heat of oxygen at 500 C was usually 14 per cent smaller than the experimentally determined values. Of late, however, impression is gaining th at the theoretical values are more likely to be correct than the experimentally de termined values, particularly in view of the work of Eucken and Mucke. The foundation of the theory of this method of determination is briefly as fol lows: The energy supplied to a gas being heated appears as molecular energy, par ticularly as kinetic energy in motion of translation, kinetic energy in motion of rotation, and the energy of atoms oscil lating back and forth in the molecule. If the distribution of energy in a single molecule be known, the internal energy and hence the specific heat of the gas can be determined. The most probable dis tribution of energy in this case may be computed by using the laws of statistical mechanics. In such a case, however (apart from the matter of motion of trans lation), no arbitrary intermediary values of energy in a molecule arc possible, as was assumed in the classical kinetic the ory of gases, but only a certain number of predetermined stages of energy. In the case of the energy of rotation these stages lie so close to each other that, in so far as their effect on the specific heat is con cerned (w ith the exception of what hap pens at very low temperatures), the same values as in the classical kinetic theory of gases are obtained. It is only in the case of hydrogen that this is true for tempera tures above room temperature. The determination of the individual stages of energy in a molecule, and par ticularly of the energy of oscillations, can be effected by observing the spectrum of the gas concerned, since, in accordance w ith the teachings in atomic physics each line of the spectrum corresponds to the transition between two different states of the molecules, which means two different stages of energy. Here the wave length of the particular spectrum line is inversely proportional to the dif ference in energy between the two stages of energy of a molecule. Further, since the wave length of light can be measured w ith great precision, the specific heat of a gas can be determined by this process w ith a precision unattainable when direct measurement is resorted to. In the case of carbon dioxide' the in vestigation of the spectrum has not yet been ^completed, so that the precision of measurement is still comparatively slight. The values of the specific heat of gases used in the present investigation, are given in a table in the original ar ticle. The computation was carried out by means of the Planck-Einstein formula, based, however, on a somewhat simph" February, 1936 121 fied scheme of the spectrum. The equa tions with the necessary constants will be found in the Landolt and Bornstein Physico-Chemical Tables (in German). The author gives an equation for the computation of the entropy of a simple gas. In this equation he employs a function F(T), which expresses the functional relationship between the entropy of a semiperfect gas and the temperature. He also gives an equation for the compu tation of the adiabatic. The theoretical values of specific heats cannot be applied to gasoline vapor, because only com paratively simple molecules containing a few atoms of the spectrum can be handled in such a manner as to obtain all the necessary constants. The specific heats for gasoline vapor, however, have been determined elsewhere and otherwise. DISSOCIATION In past publications dealing with dis sociation of gases in the internal-combus tion engine the only cases that have been considered were the breakdown of carbon dioxide into carbon monoxide and oxy gen and of water vapor into hydrogen and oxygen. In addition to these two reactions within the range of tempera tures existing in an engine, others have great importance. Thus, the formation of hydroxyl according to the equation 2H20 + 0 2 <=4OH..........[7] in combination w ith the equation for the dissociation of water 2H20 ^ 2H2 + 0 2........... [6] giving 2H20 20H + H2..........[7a] is more important than the dissociation of water vapor according to Equation [6]. To this should be added the break down of hydrogen and oxygen into their atoms. H2 2Hj or 0 2 2 0 i . . [8], [9] and the formation of nitrogen oxide N 2 X 0 2 <=*2NO............ L10] Finally, there is the water-gas reaction H2 + c o 2 H 20 + C O ... [11] to be used in the case of gases containing hydrogen and carbon monoxide. From this the author proceeds, to the presentation of a notation by means of which the dissociation may be indicated. Among other things, the relation be tween the composition and temperature is indicated. He does this by intro ducing a constant Kv which depends only on temperature and increases when the temperature rises. Equation [14] in the original article, the value of K, is next derived. It contains entropy constants, though up to quite recently their values could be determined only experimentally by direct measurement of the degree of dissociation. These measurements, how ever, greatly lack in precision. The idea arose, therefore, of determining the absolute entropies of the individual gases by processes based on the observa tion of changes of specific heat of the bodies under investigation at extremely low temperatures. Thus Eucken, Karwat, and Fried have determined for a number of gases the constants of vapor pressure which have direct functional re lationship with the constants of entropy. Schmidt, who has been closely studying the subject of dissociation, has computed the constants of entropy from the relation T dQJT The two processes are interchangeable and therefore, given the same experi mental numerical values, should give the same results. It so happens, however, th at in the final results no more precision may be expected from these processes than from direct measurements of disso ciation, as the author explains in detail. (Dr. of Eng. H. Khl, Forscbung auf dem Gebiete des Ingenieurwesens, issue B, vol. 6 , no. 373, July-Aug., 1935) LUBRICATION Automatic Lubrication IN THE latest models of electric accounting machines of the Inter national Business Machines Corporation the mere raising of a T-handle of a lubri cator provides the impulse th at oils all of the bearings simultaneously. The entire operation of lubricating the ma chine requires only a few seconds. A sectional view of the new lubricator is shown in Fig.- 3. A small piston pump is operated by a T-handle at the top of the reservoir. A coil spring forces the piston downward to feed oil into the system. This lubricating system, which is known as the Bijur, w ith the single reservoir reaches and serves 90 bearings. The schematic diagram shown in Fig. 4 in the original article gives some idea of the arrangement of the component parts of the lubricating system. In the normal position the pump piston is held down by the operating spring and the pump outlet is mechanically closed. When the T-handle is pulled the piston is raised, compressing the coil spring and drawing oil through the hollow piston and ball check valve into the pump cyl inder in the space under the piston. The piston fit in the cylinder is sealed with a cup leather. As the T-handle is released, the coil spring forces the piston downward and the upward rush of oil lifts the valve PIG. 3 SECTIONAL V IEW OF BIJUR LUBRICATOR ball to its seat in the piston. The meas ured charge of oil trapped in the cylinder below the piston is then automatically forced through the felt filter into the oil feed lines by the pressure of the spring. The stroke of the piston is adjustable so that any predetermined amount of oil may be fed into the lines at each opera tion of the pump. Metering fittings or "drip plugs" (Fig. 6 in the original article) form an important part of the lubricating system. Each bearing has its own drip plug and this device controls the amount of oil fed to that particular bearing. The pump, therefore, measures the total quan tity of oil fed into the system and the drip plugs proportion this quantity ac cording to the requirements of each bearing. As the amount of oil required by some bearings is greater than that re quired by others, drip plugs w ith larger flow rates are used for the larger bearings. Further information about the drip plugs will be found in the original article. 122 M echanical Engineering This is a closed lubricating system and the oil is fed to the bearings in the form of a heavy film. It is impossible for dirt to be fed into the bearings w ith the lubricant. (Fred M. Hew itt in Machine Design, vol. 7, no. 10, October, 1935, pp. 19-22,7 figs.) New Developments IN A discussion of modern methods of refining oils, Dr. A. E. Dunstan said it was quite conceivable that if a lubricat ing oil were merely a lubricant it would not be refilled at all, because, obviously, in the process of refining, the exceedingly valuable polar bodies, from the lubricat ing point of view, were necessarily re moved. On the other hand, these same polar bodies were an intolerable nuisance in practice, and therefore petroleum lu bricating oils had to be refined in order to separate these particularly active and objectionable substances, which con ferred polarity and the property of re ducing friction. Possibly, however, it was only fair to say that King's recent work on lubrication in connection w ith one of the committees of the Department of Scientific and Industrial Research showed that although these bodies could be removed, the lubricating oil soon pro duced them again, so that in the long run not much was lost. For many years the ordinary routine practice of refining mineral oil had been based on the work of James Young, and took the form of the removal of the un saturated polar bodies by acid and the removal of the traces of acid by absorp tion, but during the last year or two there had been impor tant new developments, prob ably brought about by the pioneer work of the Standard Oil Company of New Jersey on the hydrogenation of mineral oils. In the course of that work it was shown that from a conventional mineraloil stock there could be ob tained a highly effective, highly refined, and extremely useful oil characterized by a very flat viscosity curve. These modern methods were coming into practice and would steadily increase in their application. They de pended on the specific solu bility of unsaturated and polar bodies in a variety of sol vents, which resulted in in creasing what m ight be called the " paraffinicity" of the oil. This tr e a tm e n t could be brought about by a large number of solvents, and a few of these solvents which had proved quite effective, parti cularly in the United States, were nitro benzene, phenols, sulphur dioxide mixed w ith benzolene, cresols, furfural, and ftS-dichlorethylether. (Discussion be fore Section G--Engineering of the Brit ish Association Meeting at Norwich, abstracted through Engineering, vol. 140, no. 3642, Nov. 1,1935, pp. 481-483) MACHINE TOOLS Hydraulic Indexing H YDRAULIC indexing is used in the Hammond boring and reaming ma chine. A heavy table carrying five auto mobile cylinder blocks on which the ma chining operations are performed is auto matically indexed through 72 deg by fluid motor F, Fig. 4, the rotation being effected through spur pinion T in mesh with ring gear A bolted to the underside of the table. A foot pedal at the floor level sets the fluid motor in motion to carry out the in dexing cycle. As the operator steps on the foot pedal, which is connected to lever B, Fig. 4, lock-bolt C is withdrawn from its guide bushing in the table which now is free to be rotated. As the bolt re cedes it carries w ith it an integral plate D which operates limit switch E. A solenoid is energized to open valve N and allow oil pressure to actuate the fluid motor F. When the table has revolved 72 deg, dog G on the underside of the table comes into contact w ith a plunger on valve H and stops the fluid motor. Subsequently lock bolt C snaps into engagement with a guide bushing in the table, operating the limit switch E through plate D in a direc tion opposite to that at the beginning of the index. This energizes another solen oid to actuate valve 0 and consequently advance the four tool heads into work ing position. (Harold B. Veith in Ma chine Design, vol. 7, no. 7, July, 1935, pp. 26 and 67) METALLURGY Cerium in a Light Alloy NEW alloy called Ceralumin "C," which consists of nickel and alumi num w ith a small addition of cerium has been developed by the J. Stone Co., Ltd., London. It is a casting material con taining iron (about 1.2 per cent) and aluminum as the main constituent. Tests have indicated that cerium allows the beneficial mechanical effects of a high iron content to be obtained by sup pressing the embrittling constituent which is otherwise likely to be formed. The heat-treatment applicable to this alloy is quite simple. Castings arc maintained at the solution temperature of 515 to 535 C for from four to six hours and then quenched in water; aging is achieved by heating to 175 C for 16 hr, followed by quenching in water. The risk of distortion at the solution tem perature is no greater than that involved, for example, in heat-treating "Y " alloy at 520 C. February, 1936 123 jn the heat-treated condition Ceralumin "C" presents a combination of tensile strength a t ordinary and elevated temperatures, high elastic limit, hieh Brinell hardness, and exceptional fatigue strength of 18,500 lb per sq in. at 2 0 ,000,000 cycles. The alloy is said to be suitable for high-duty service in the form of die-castings, chill castings, and sand castings. If, after quenching, the aging treat ment is omitted, aging at room tem perature takes place, and after five days a modified form of the alloy is produced having somewhat lower tensile strength but increased ductility. This modifica: tion is intended for purposes where ex tra toughness is required in castings, such as for shrinking-on cylinder heads where heavy stresses may be set up and a little "give" in the casting is essential. (Machine Design, vol. 7, no. 10, October, 1935, p -29,1 fig.) m o t o r -c a r e n g i n e e r i n g Cotal Electrically Controlled Gear Box THE Cotal is an epicyclic gear w ith magnetic clutches and a simple form of remote control. It has been exten sively tested in France and preparations are being made to manufacture it in England where some tests of it have been made. The chief object of those tests was to determine whether a high-powertransmission efficiency could be obtained in all ratios and whether the tempera ture of the box remains low during pro longed full-load operation. The ratios in the box tested were 4.231, 2.610, 1.621, and 1.0 to one, and the transmission efficiencies w ith approxi mately full engine torque were 92, 94, 96, and 98 per cent. These figures allow for the slip in the fluid coupling which would account for nearly 2 per cent of the power-loss figures of 8, 6 , 4, and 2 per cent. ' During a 3Vr-hr run w ith all the ratios in use and under almost continuous full load the temperature of the box rose to 159 F, the room temperature being 75 F. The smallness of the temperature rise, while being another indication of the high efficiency of the Cotal box, is to be attributed in part to the arrangements for maintaining a rapid flow of lubricat ing oil from the inside of the box where the gears are at work, to passages in the outer casing where the filter and pump are located. One of the drawings in the original article shows the outline of the box tested, and from this it is apparent that the unit is extremely compact; it is in fact considerably smaller than other gear boxes designed for a similar duty. (Diesel Railway Traction, Supplement to Railway Gazette, Oct. 4,1935, p. 567) Duoautomatic Hydraulic Braking THIS is a device used on Hudson cars for 1936. Every emergency applica tion of the' hydraulic brake is backed up by a mechanical application which be comes operative when the pedal has been moved through three-quarters of its range, or in the event the hydraulic brake fails. The first part of the travel of the pedal applies the hydraulic brake. After a certain movement the pedal picks up a link connected with the mechanism that applies the emergency brake to the rear wheels. (Automotive Industries, vol. 73, no. 17, Oct. 26, 1935, pp. 550-552, 4 figs.) Victor Touring Car With Airless-Injec tion Engine THE first touring car fitted with an airless-injection engine to be offered to the public in England was recently demonstrated there. It consists of a horizontally opposed twin-cylinder en gine in a Jow ett chassis. A fuel con sumption of 1 gal per 65 miles, and a lubricating-oil consumption of 1 gal per 2000 miles are claimed. Both the engine and the chassis separately have been ex tensively used, the former in motor-boar work. The engine is of the air-cell type and has a cylinder bore of 80 mm and a piston stroke of 100 mm, giving a capacity of 1000 cu cm. The cylinder heads of cast iron are detachable. The cylinders are provided w ith removable wet liners and the pistons are of aluminum alloy with gudgeon pins of the fully floating type. (Engineering, vol. 140, no. 3640, Oct. 18, 1935, pp. 416,1 fig.) POWER-PLANT ENGINEERING 60 Per Cent Steam-Power-Plant Efficiency T HE paper claims th at it is possible to organize industrial steam generation and utilization to operate at an overall efficiency of more than 60 per cent, even though the most efficient super power stations today generate electricity at an overall efficiency of less than 30 per cent. The new higher efficiency is to be obtained by utilizing the latent heat of steam through a combination of steampower generation and heating. Ex actly how this is to be done the paper does not show, however. It is fully realized that this ideal cannot be attained over a short period of time, but it is definitely the goal toward which effort must be made if progress is to be secured along the line of cheaper elec tricity and more economical working of the power plant. If this ideal is kept clearly in mind, there is little doubt that local district schemes can be de veloped, which w ill merely be an elabora tion of many industrial schemes already in successful as well as economic opera tion. The policy of developing steam-power schemes by districts rather than by in dividual industries as at present will bring w ith it a number of subsidiary advantages. Steam generation will be under the control of qualified engineers, and the plant will be arranged for the highest generating efficiency. Heat and power will be "on tap" not only for industrial works, but also for business houses and domestic needs; and in the latter cases there w ill be a considerable saving in labor and also elimination of dirt, and heating will be more efficient due to the continuous maintenance of a normal temperature. (The Steam Engi neer, vol. 4, no. 12, September, 1935, p. 506) Safety Valves in High-Pressure Boilers THE safety valve was primarily de veloped at the time when the large water-drum boiler was principally used. In the case of such a boiler the steam can be blown off safely because the amount of water contained in the boiler is so large that when the safety valve is suddenly opened enough time is available for the feeding device to prevent the water level in the boiler from going down too much. On the other hand, in the highoutput boiler, the amount of water available is small and under certain con ditions the sudden opening of a safety valve can bring about such a reduction of the water content in the boiler as to cause overheating of the tubes with all that this involves. Furthermore, when the safety valves of a high-pressure boiler are blown the action of the steam is so extra ordinarily erosive as to produce lack of tightness in the valve when returned to its seat. This happens when the steam pressure is in excess of 30 atm. It is stated that when this happens it takes a week to replace the valves in order to give them a tight seat. A German de vice by which this condition may be avoided is described in the original article. (Archiv fur Warmewirtschaft und Dampfkesselwesen, vol. 16, no. 9, Septem ber, 1935, p- 226) 124 M echanical Engineering High-Output Sectional-Chamber Inclined-Tube Doebler Boiler THE purpose of this boiler is to com bine the advantages of an inclinedtube and a vertical-tube boiler. The fundamental idea is to assure water cir culation under all conditions. In the design of the boiler particular attention was paid to the requirement that when the steam is removed and water to replace it admitted there shall be no material resistances between the sectional chamber and the boiler cham ber. The circulating tube is therefore arranged so that it can be used to take steam from the forward sectional cham ber while water is being added to the real sectional chamber. To do this the cross section of these tubes is made at least as large as the free cross section of the sectional chambers which they join. In order to permit the steam generated in the boiler tubes to move as fast as possible in a predetermined direction, the bundle of boiler tubes is inclined more steeply than usual. The position of the boiler tubes at less than 45 deg was found to be the most desirable. Because of this the upward flow of steam bubbles is facilitated, and the return flow of water assured. This was done by creating a useful static head produced as a result of locating the lower boiler tube ends at a low point and making the sections of great height. W ith the boiler tubes set at a steep angle the static head in the upper row of tubes is not less than in the lower row of tubes. This great head on the lower ends of the boiler tubes affects water circulation favorably under all conditions, and disturbances in the flow of steam inside of the upper rows of tubes have never been observed in practice. ARRANGEMENT OF CONNECTING TUBES The upper row of steam-carrying cir culation tubes is located so high that under all conditions it is above the water level in the boiler drum. The connect ing tubes located below it serve more for water circulation. The rearmost row of the back circulation tubes serves pri marily to admit the feedwater. The other tubes of this kind are engaged in providing water circulation. The reli able supply of feedwater provided by the lower drop tube rows is assured by the installation of a properly proportioned sheet-iron baffle. The feedwater trough in th e b o ile r d ru m is as lo n g as t h e tu b e system is wide. The feedwater coming in is distributed by means of the trough over the entire width of the boiler. There is the same number of circula FIG. 5 DOEBLER BOILER, 23 ATM 450 C ("jtssblser = soot blower; Schauluken = peep hole; Erdgasbrenner = natural-gas burner; Wanderrost = traveling grate; Lufterhitzer = air preheater; Kanal gum Einsaugen der Khllujt von der hinteren Feuerkammerwand = duct for taking in cold air by suction from the rear combustion-chamber wall; Saugzuganlage = suction draft; Asbest = asbestos; Steige eisen = stirrup.) tion tubes front and rear, and these tubes are of equal length, thickness, and shape, there is likewise an equal number of sectional chambers. This simplifies the manufacture and facilitates replace ments. The fact that all the elements are alike results in a perfectly symmetri cal construction of the boiler, while the uniform distribution of heat expansion over the entire boiler is also facilitated. Furthermore, the water circulation is uniformly distributed over the entire w idth of the boiler, while temperatures of the heating surfaces coming in contact w ith water are approximately the same, and undesirable heat stresses are elimi nated. HEATING THE DOWNCOMERS In order not to disturb the water cir culation an attem pt was made not to permit generation of steam in these tubes. The best way would have been to place the tubes entirely outside of the gas stream. While this step, under certain conditions, might have been fully justi fied, it would be going too far to use this arrangement as a basic element in every kind of boiler. In modern boiler opera tion there are conditions which not only permit the low heating of the down comer, but in the interest of simpler boiler construction, make it desirable. In the sectional boiler here described these tubes are placed in the last stack behind the boiler area, where the gases have been so effectively cooled that only a small amount of heating is provided. Moreover, the heating surface of the economizer has been so proportioned that the feedwater temperature at the entrance to the boiler is at least 30 C lower than the boiler temperature. The feedwater admitted, together with the circulating boiler water, is immedi ately led into these downcomers and the water is supplied w ith the amount of heat just necessary to bring it to the boiling temperature. Quite a number of these boilers have already been installed and are apparently giving satisfaction, although in Ger- February, 1936 125 this type is as yet little known, n lw of tests are given in the original 'tick- (A- D eMer in ^tchiv fur %Varmewirtschaft uni Dampfkesselmsen, vol 16, no. 9, September, 1935, pp. 233-235,2. figs-) SPECIAL MACHINERY Electrography ELECTROGRAPHY is a new method of electrostatic recording. At a meeting of physicists in Hamburg in 1928 the author presented a high-vacuum cathode-ray tube w ith which oscillo grams were to be recorded on the sur face of a body by means of negative charges of electrons. This left an in visible record which could be then "de veloped" by spraying over the glass sur face a powder carrying positive electrical charges. At the time this process was described it had barely passed the initial stages of experimentation. Of late, however, the author succeeded in de veloping it to the point where the record ing of electrical processes by means of electrostatic charges could be carried out FIG. 6 APPARATUS FOR ELECTROGRAPHICAL RECORDING in the open, w hich offers important possi bilities for the technical and physical application of the process. The apparatus used in this process is diagrammatically shown in Fig. 6 . In principle it is comparable to the opera tion of three electron tubes or Braun tubes. The hot cathode K consists of a platinum strip or wire covered with barium oxide. At a distance of a few tenths of a millimeter from the cathode is located a metal screen G which has two functions to perform. In the first place, the opening of a slot limits the cross section which the stream of ions can pass and in the second place the screen oper ates as a grid or a Wehnelt cylinder, in that the potential induced in the screen controls the magnitude of the stream of 10ns. The metal plate A is the anode. Its forward surface is covered w ith a good msulator P, such as ebonite, lA to V2 mm thick. The distance of the plate P from the metal screen is also as small as possible, say, about x/ 3 to 1 mm. If the cathode be heated and a potential of 500 to 1000 volts be induced for a short time in the anode, the ions flow through bered collars or similar indicators which the opening in the grid and charge the are attached to the shafts or parts. Sup surface of the ebonite plate. If the latter pose that the intended speed of a certain be then dusted, a clearly marked round shaft is 200 rpm. The collar applicable spot is brought out. If the electrical to this shaft has the number 15 marked at charge on the anode be left for a longer equally spaced intervals fifteen times time the bundle of ions flowing through around its periphery. As an alternative the opening spreads out, the spot becomes an equal number of reflectors which greater, and finally may attain a diameter catch the light from the stroboscope and of 5 to 6 mm. On the other hand, if return it to the observer's eye may be during the exposure of the anode and provided. Since a 200-rpm shaft makes ebonite plate they are moved in their one-fifteenth of a turn in one-three thou plane, the bundle of ions records a sharp sandth of a minute, it is clear that if the line on the plate. This electrical line is shaft is running at its intended speed, the the thinner the faster the anode is dis numbers of reflectors on its appropriate placed, but at the same velocity of dis collar will appear stationary when illu placement, the thickness of the line de minated 3000 times a minute. If it is pends on the grid voltage, and the line is running slower or faster the numbers will the narrower the more negative the volt appear to move around against or with age on the grid has been selected. This the rotation of the shaft. If it is desired is explained in detail in the original ar to determine by how much the shaft is ticle which also shows samples of rec running slow or fast, it is sufficient to ords. (P. Selenyi in Elektrotechnische count the rate at which the numbers dis Zeitschrift, vol. 56, no. 35, Aug. 29, 1935, appear from view for the apparent rotary pp. 961-963, 8 figs.) speed of the numbers equal to the dis crepancy between the actual and the in TESTING AND MEASUREMENTS tended speeds of the shaft. The device may be used to measure any speed of the The "Relator" Speed-Checking System shaft, such as 110 rpm and not merely an exact submultiple of 3000. ( The Engi TROBOSCOPES can be used both for neer, vol. 160, no. 4162, Oct. 18, 1935, p. measuring the speed of rotating parts 409, 1 fig.) and for checking whether this speed is right. In the latter case the stroboscope has a constant setting, in the former it VARIA has to be adjusted to suit each case, which is a time-consuming process pre senting opportunity for the commission The Machine Age in the Glass Industry of errors. It is claimed that this particu lar difficulty has been overcome in the new stroboscope developed in England by IN A presidential address to the Fourth Glass Convention (Great Britain) the author says that he believes that the A. J. Ashdown, and called the "Relator" universal adoption of mechanical proc system. esses is bound to increase unemployment This apparatus comprises a strobo unless sufficient machines are installed to scopic device working at constant speed absorb all those who were previously w ith high accuracy, and consisting of a engaged in the hand-operated processes. " gun" which throws a whirling beam of The glass industry is in a peculiar light on to the part, the speed of which condition because the question of the is to be checked. This whirling beam proposed compulsory introduction of may be considered as equivalent to a sta the four-shift system into glass works By tionary rate which is interrupted 3000 means of an international convention times a minute for the standard rate of has been before the International Labor w hirl of the beam of 3000 rpm. At one Conference at Geneva. In 1934 the con point of the whirl the object toward vention was adopted by the Conference which the beam is directed is illuminated prescribing, as far as sheet-glass works by the light over the rest of the whirl; were concerned, a four-shift system, the light does not fall on the object. each shift of eight hours' duration and The whirling beam therefore effects the the hours averaging 42 per week taken same results as when interrupted by the over a period of four weeks. The mechanical and electrical objections asso author tells the experience of his firm ciated with high-frequency interruption in the plate- and sheet-glass industry. of illumination. The following comparative results In order to make a stroboscope of fixed- of the six months prior to and the six glimpse frequency applicable to shafts or months after the inception of the scheme other parts of machinery running at vari are reported. The reduction in hours ous speeds, the device makes use of num per person was 10 per cent. The in- 126 M echanical Engineering T crease in output was 15 per cent (trade The method for determining the forge actually improved in this period). The ability of welds is described in the W elding and Failure of Machinery if HIS following editorial is based on increase in th e number of employees was original article. annual reports of the British Engi only 8.4 per cent and represented in actual The conclusions to which the author neering Insurance Company: numbers 500 men and women. It should comes is th at in the case of electric The introduction of welding into ma also be observed that before the scheme autogenous and atomic arc welds with chine construction has produced a pos many men were on short time. The out unalloyed uncovered welding rods tensile sible new source of failure, as is demon put value per man-hour went up 11.4 strength is not improved by forging. strated by the details given in the report per cent. The average weekly earnings The angle of bend in the case of an elec under notice, concerning the failure of a were unchanged. The scheme has now tric weld forged at 800 to 700 C is some motor shaft, due to the effect of the weld been adopted as permanent, and it can what lowered because of critical defor ing-on of fan-blades. Here, rupture oc be truthfully said th a t the employee is mation, but increases as compared w ith curred on the shaft at the root of one of happy because, although his wages unforged samples when the weld has the blades, after 12 months' service, and have not been affected, he is enjoying been forged at a higher temperature. it is reasonable to assume th at the ve greater leisure. In this particular case In the case of autogenous and atomic locity of rotation was fairly uniform, the employer is also able to say th at his arc welds there is no improvement at all, since the shaft was driven by an electric costs have not been increased, though due to the fact th a t the test pieces as motor. Moreover, it was found that in one should draw attention to the 15 delivered have already a bend angle of dependent cracks had started in line with per cent increase in total output which 180 deg. five of the six blades, so that the trouble has to some extent obscured the issue. The notch toughness of electric welds was not confined to one weld that might If it is possible to apply this system to one w ith uncovered rod is lowered by forg have been faulty. Although the metal part of the glass industry, it is worthy of ing because of the high content of proved to be sound, the break involved serious consideration by others. oxygen and nitrogen. In the case the tearing away of part of the shaft and The author stresses the great impor of autogenous and atomic arc welds a complete blade, whence it is possible to tance attached to being able to consider forging at 800 to 700 C produces at first infer that the vibration of the rotating such problems as these in conjunction a reduction of notch toughness because blades was the means of producing an w ith representatives of the labor in of critical deformation. By forging, increase of stress, due to the reflection of the form of the Plate and Sheet Glass however, at 150 deg C the notch tough the stress-waves at the interface of the Industrial Council, which enables not ness improves materially because of welded and parent metals. The phe only problems concerning hours of grain refinement, but forging at still nomenon of reflection would be affected employment and rates of pay in the higher temperatures makes matters worse by the emulsified condition of the pear- industry to be fully examined by both again because of the appearance of coarse litic structure found under each weld, for sides of the table, but also frank discus grains. W ith the deformation of 20 to the original interfacial conditions are sions from time to time on the state of 40 per cent the same static and dynamic naturally modified by heat-treatment of the industry itself and the conditions of values have been obtained for all kinds any kind, and by the presence of contrac world trade generally. of welds. tion cracks. Such discontinuities in a The next subject discussed is mechani In practically every case where weld metallic structure would be partially re zation and quality of product. The ing rods w ith higher carbon and man moved by heat-treatment, but it is not author believes that improvements in ganese contents have been used, forging always easy to effect the necessary treat design of mass-produced articles are both at 1050 to 950 C produced a mechanical ment where a large casting or shaft is possible and desirable. (Geoffrey L. improvement in practically every case. involved, for which reason there is a Pilkington, Journal of the Society of Glass From a picture of rupture of forged test need for research into the transmission of Technology, vol. 19, no. 75, September, pieces made from pure welds, and by stress-waves across the interface of 1935, pp. 106-111) the determination of the work of de welded materials. The report also con formation, it becomes possible to deter tains an account of the failure of shafts WELDING mine in a laboratory the degree of im in the consideration of which attention provement of test pieces by forging. might be given to the examination of the Forgeability of Welded Joints It appears that up to a forging tempera transmission of stress waves along a shaft ture of 1050 to 950 C forging produces carrying a massive flywheel, which, in THIS investigation was to determine what influence forging has on the quality of welded joints, and, in par an increase in the work of deformation, while if the forging temperature is in excess of 1050 C, work of deformation acting as a reservoir of energy, imposes an alternating torque on the shaft. Since it is by no means easy to treat the practical ticular, how the heat of forging and the decreases. problem along mathematical lines, it is deformation in forging, the composition Welded joints made with welding rods very much to be hoped that Professor of the welding rod, and the character of of higher carbon and manganese content, Coker's photoelastic method will subse the welding process react on the forge reach the highest degree of forgeability quently be applicable to the general ability of the joint. Two testing proc when the addition of alloying elements problem of stress waves. Such an ex esses have been developed to determine produces a more powerful deoxidation perimental procedure may elucidate the the forgeability of a weld in the labora of the weld. It has been also found that significance of the fact that a number of tory and in the field. atomic arc welding produces the highest the failures occurred on the shafts in the This is quite an extensive paper, and degree of forgeability, autogenous weld neighborhood of a flywheel, or a crank- am o n g o th e r th in g s i t discusses th e ing a medium, and electric welding w ith arm, which corresponds to a sudden matter of forgeability as a function of uncovered rod the lowest degree of change of load and of cross section in the the forging heat. The influence on forge forgeability. (Heinz Becker in Auto path of a wave traveling along a shaft. ability of the carbon content in the weld gene Metallbearbeitung, vol. 28, no. 13, (Editorial in Engineering, vol. 140, no. ing rod of the manganese content therein. July 1 , .1935, pp. 193-202,27 figs.) 3641, Oct. 25, 1935, pp. 449-450) LETTERS AND COMMENT Brief Articles of Current Interest, Discussion of Papers, A.S.Ai.E. A ctivities 7 Fabricated Housing T o the E d it o r : The article on " Prefabricated Hous ing" which was published in the Septem ber, 1935, issue of M e c h a n ic a l E n g i n e e r in g points out the various economic factors underlying the demands for fac tory fabrication of houses. It has been stated th at three-fourths of all the fami lies in this country can afford no more than $25 a month for shelter. It is the writer's belief that the only type of house which can be purchased at this price and which can be prefabricated completely is one evolving naturally from the house car or automobile trailer. This sub stitute for the conventional home on a fixed site conceives the house and fur niture as a unit completed in the fac tory, and delivered ready for immediate occupancy on a basis similar to th a t on which the automobile is purchased. With these thoughts in mind, the writer has designed tw o types of pre fabricated houses. The first of these is a trailer-type l W ton house w ith three rooms and a bath. Sewer, gas,water, electrical, and telephone connections can be made to these utilities through a single coupling. On the first floor of this unit is an 8 by 12-ft cabin, a 4 by 12-ft galley diner, a dressing room, and a 3 by 8-ft combination bath and laundry, while on the second floor is an 8 by 12-ft bedroom incorporating a builtin means of maintaining the low over all height of the house. The frame of the house, constructed of wood and steel, is supported by the individually sprung wheels attached directly to the trussed side walls which are covered w ith a weather-faced hot-plate plywood ma terial. This design has been designated as the "Nomad" unit by the writer. The second house designed by the writer is called the "Mobile House" and can be built w ith as many as ten rooms and two baths. The central structure of this unit contains four rooms and a bath and has 600 sq ft of floor space. There is an 11 ft 3 in. by 16-ft living room, a kitchen containing an electrical re frigerator and an oil-heating unit, two bedrooms on the second floor, a complete bathroom, and a laundry w ith an elec tric washing machine. This unit weighs 4 tons and can be moved by truck over an improved highway by special permit. It is designed so th at it can be set up on a foundation of hidden concrete wheels if it is to be sold as chattel or mounted on four steel posts. The frame of the house is constructed of wood and steel and is designed with bridgetruss walls so th a t it can be placed on the foundation posts or over a basement on a continuous wall. Various hoods, porches, pergolas, single rooms, and second-story units may be added until the house becomes a ten-room unit w ith two baths. The central four-room unit, how ever, is standard and contains all the complex and costly parts of the structure. The house is designed so that its struc tural units can be jig-cut and jigassembled in the factory. Units needed for erecting more than the four-room cen tral structure are stored in the central structure while it is being moved to the home site and there they are removed and assembled. One of the "Mobile" houses has been erected in Flint, Mich., and has been ex posed to climatic conditions long enough to indicate what problems must be solved by manufacturers of prefabricated houses. The great differential between inside and outside temperatures in severe climates w ill result in the collection of condensa tion moisture on the thin plywood walls of prefabricated structures to an even greater extent than on the walls of the conventional house. The plywood wall of the prefabricated house with its joints closed with glue or mastics is excep tionally liable to damage from this source. Moisture accumulated during the winter between the walls of prefabri cated houses is apt to cause serious dam age to the plywood structures. In the " Mobile" units described by the writer double air spaces have been utilized to eliminate this trouble. The problem of damaged plywood exteriors, caused by the disintegrating effect of sunlight, moisture, expansion, and contraction, must also be met satisfactorily by the manufacturer of prefabricated houses. This problem has been solved in the con struction of the " Mobile" unit by utiliz ing a special type of fiber-board exterior. 127 The writer is of the opinion that the solution of the low-cost-housing prob lem lies in manufacturing a complete house which is strong and light enough to be delivered cheaply over a consider able radius and which can be sold at a c?t ^ .i c h the lower-income groups can afford, to pay. C o r w in W illso n . 1 A Modem Dust Collector To t h e E d i t o r : . ^ dumber Qf considerations have been introduced by H. Van Tongeren in his paper which warrant careful study by the power engineer interested in the re moval of fly ash from flue gases. One fundamental consideration in any at tempt to solve this problem requires an economic solution by carefully comparing the lowered nuisance factor, resulting from a decrease in particle size, w ith the increased first cost and operating ex pense involved in collecting such smaller particle sizes. Any attempt to by-pass this problem by considering only total collection effi ciencies does not really simplify it be cause the investment and operating ex pense necessitated by a given total effi ciency will depend on the distribution of particle size in the fly ash. This effi ciency will be higher for increased pro portions of very fine particle sizes. Thus, the final analysis still necessitates the weighing of increased cost against the lowered nuisance effect by a decrease in the particle sizes allowed to escape to the atmosphere. Irrespective of the solution decided upon, the engineer is still confronted by the fact th a t some particles will escape w ith the flue gases, inasmuch as any at tempt to collect them would be prohibitive. How does the difficulty of collec tion increase w ith decreasing particle size, and what factors are involved? Such questions can best be answered from a study of Stoke's law. This law gives th e ra te of fall of spherical particles un- Abiding Research, 318 Welch Blvd., Flint, Mich. ,, A Modern Dust Collector," by Herman V an Tongeren, M echanical E n g in e e r in g , voL 57, December, 1935, pp. 753-759. 128 M echanical Engineering der the influence of gravity in terms of physical constants, and therefore, it ap plies primarily to settling chambers. However, it can readily be extended to cover centrifugal separators, which are adapted to separate smaller particles from larger gas volumes than can be handled in settling chambers. While Stoke's law applies only to spherical particles, other particles can be included in the analysis by defining equivalent spherical particles which would fall at the same rate in still air. The rate of fall of spherical particles in still air as given by Stoke's law is where v = the rate of fall of spherical particles in still air, r = radius of an equivalent spherical particle, w = spe cific weight of the particle, w' = specific weight of gaseous fluid, n = viscosity of gaseous fluid, and g = acceleration due to gravity. Formula [1] can be adapted readily to centrifugal separators by re placing the acceleration of gravity g by radial acceleration. The rate of fall then corresponds to the entrainment velocity which will support the particle against the radial acceleration. Formula [1] then becomes 2 2 v = y where V = tangential velocity of the particle, R -- radius of curvature of the path, and the other terms are the same as given previously. I t is convenient to divide the radial acceleration V 2/R by the acceleration due to gravity g, thus ob taining a pure ratio defining a separation factor which indicates how many times gravity is multiplied in the centrifugal apparatus. Formula [2] shows the qualitative re lationship between the various physical factors involved. In order to obtain a quantitative basis for judgment, Table 1 has been prepared giving the entrainment velocity of equivalent spherical particles of unit density through air at 212 F when the separation factor is one thousand times gravity. By observing the rela tionship in formula [2], the entrainment velocity under any other conditions can be readily determined. It is to be noted that the viscosity of the entraining gas varies as the square root of the absolute temperature. Table 1 illustrates th e difficulty of separating single isolated particles from a large gas stream, and how this difficulty increases w ith decreasing particle size. In addition, it must be kept in mind that the practical solution embodied in the equipment must be such th at the theo retical conclusions can be closely ap proximated. In this connection, the so lution proposed by Mr. Van Tongeren merits careful consideration. TABLE 1 ENTRAINMENT VELOCITIES OF PARTICLES OF UNIT DENSITY THROUGH AIR AT 212 F Entrainment ------ Diameter of particle------, velocity at Microns In. Mesh 1000 g, fps 104 0.0041 140 860.00 100 0.0039 74 0.0029 797.00 200 435.00 44 0.0017 325 154.00 20 0.00078 625 31.80 10 0.00039 1250 7-95 5 0.0002 2500 1.99 2 0.000078 6250 0.32 1 0.000039 12500 0.08 Some questions have been raised as to the range of particle size for which for mula [2] based on Stoke's law still holds in centrifugal collectors. In connection w ith applications where limitations as to permissible capital outlay and power costs for operation do not yet enter, ac tual operating experience has been ob tained which indicates that this range of particle size can be extended below 5 mi crons. In the operation of the micronizer re duction mill, controlled by International Pulverizing Corporation, the grinding energy is furnished directly by high-pres sure steam or air w ith initial tempera tures up to 750 F. The air or steam is also utilized for air-sweeping the grind ing zone and classifying the product. In certain instances, the high whirling motion of the gas stream is utilized for collecting the product in a centrifugal separator of the cyclone type. In com mercial operation, a collection efficiency of 98 per cent has been secured for a product having a maximum particle size of 5 microns, the efficiency being deter mined by weighing the raw tnaterial and collected product. Referring to formula [2 ], the radius of curvature R for the collector was 2V 2 in., while the tangential velocity V re sulted in a pressure drop exceeding 1 lb per sq in. Under these conditions, and taking into consideration the density of the material, the figures for entrainment velocity given in Table 1 would probably be multiplied by a factor of at least 2 5 . The collection of 5-micron material then becomes predictable from formula [2]. _______ M a r c e l A. L is s m a n . 3 3Consulting Engineer, International Pul verizing Corporation, Camden, N. J. A.S.M.E. BOILER CODE Interpretations THE Boiler Code Committee meets monthly for the purpose of con sidering communications relative to the Boiler Code. Any one desiring infor mation on the application of the Code is requested to communicate w ith the Secretary of the Committee, 29 West 39th St., New York. The procedure of the Committee in handling the cases is as follows: All inquiries must be in w ritten form before they are accepted for consideration. Copies are sent by the Secretary of the Committee to all of the members of the Committee. The interpretation, in the form of a reply, is then prepared by the Committee and passed upon at a regular meeting of the Committee. "This inter pretation is later submitted to the Coun cil of The American Society of Mechani cal Engineers for approval after which it is issued to the inquirer and published in M e c h a n ic a l E n g i n e e r i n g . Following are records of the interpre tations of this Committee formulated at the meeting of December 6 , 1935, and approved by the Council. C ase No. 756 a n d C a se No. 757 (Annulled) C a se No. 808 (Interpretation of Par. H-24) Inquiry: (a) May the provisions of Par. P-216 be applied to heating boilers as an extension of the provisions of Par. H-24? Q>) In the case of welded low-pressure heating boilers having unflanged heads, may the provisions of Par. H-24 be applied? If not, w hat would the re quirements be w ith respect to the area to be stayed and w hat would be the maximum height of the segment above the tubes? Reply: (a) The provisions of Par. P-216 may be applied to the design of low-pressure heating boilers having flanged heads. (b) Excepting only the allowance of 128 M echanical Engineering der the influence of gravity in terms of physical constants, and therefore, it ap plies primarily to settling chambers. However, it can readily be extended to cover centrifugal separators, which are adapted to separate smaller particles from larger gas volumes than can be handled in settling chambers. While Stoke's law applies only to spherical particles, other particles can be included in the analysis by defining equivalent spherical particles which would fall at the same rate in still air. The rate of fall of spherical particles in still air as given by Stoke's law is where v -- the rate of fall of spherical particles in still air, r -- radius of an equivalent spherical particle, tv -- spe cific weight of the particle, w' = specific weight of gaseous fluid, n = viscosity of gaseous fluid, and g = acceleration due to gravity. Formula fl] can be adapted readily to centrifugal separators by re placing the acceleration of gravity g by radial acceleration. The rate of fall then corresponds to the entrainment velocity which will support the particle against the radial acceleration. Formula [1] then becomes the practical solution embodied in the equipment must be such th at the theo retical conclusions can be closely ap proximated. In this connection, the so lution proposed by Mr. Van Tongeren merits careful consideration. TABLE 1 ENTRAINMENT VELOCITIES OF PARTICLES OF UNIT DENSITY THROUGH AIR AT 212 F Entrainment ---- Diameter of partici velocity at Microns In. Mesh 1000 g, fps 104 0.0041 140 860.00 100 0.0039 797.00 74 0.0029 200 435.00 44 0.0017 325 154.00 20 0.00078 625 31.80 10 0.00039 1250 7.95 5 0.0002 2500 1.99 2 0.000078 6250 0.32 1 0.000039 12500 0.08 Some questions have been raised as to the range of particle size for which for mula [2] based on Stoke's law still holds in centrifugal collectors. In connection with applications where limitations as to permissible capital outlay and power costs for operation do not yet enter, ac tual operating experience has been ob tained which indicates that this range of particle size can be extended below 5 mi crons. In the operation of the micronizer re duction mill, controlled by International Pulverizing Corporation, the grinding energy is furnished directly by high-pres sure steam or air w ith initial tempera tures up to 750 F. The air or steam is also utilized for air-sweeping the grind ing zone and classifying the product. In certain instances, the high whirling motion of the gas stream is utilized for collecting the product in a centrifugal separator of the cyclone type. In com mercial operation, a collection efficiency of 98 per cent has been secured for a product having a maximum particle size of 5 microns, the efficiency being deter mined by weighing the raw material and collected product. Referring to formula [2], the radius of curvature R for the collector was l 1/ i in., while the tangential velocity V re sulted in a pressure drop exceeding 1 lb per sq in. Under these conditions, and taking into consideration the density of the material, the figures for entrainment velocity given in Table 1 would probably be multiplied by a factor of at least 25. The collection of 5-micron material then becomes predictable from formula [2]. M arcel A. L issman. 8 . 3Consulting Engineer, International Pul verizing Corporation, Camden, N. J. where V = tangential velocity of the particle, R = radius of curvature of the path, and the other terms are the same as given previously. It is convenient to divide the radial acceleration V 2/R by the acceleration due to gravity g, thus ob taining a pure ratio defining a separation factor which indicates how many times gravity is multiplied in the centrifugal apparatus. Formula [2] shows the qualitative re lationship between the various physical factors involved. In order to obtain a quantitative basis for judgment, Table 1 has been prepared giving the entrainment velocity of equivalent spherical particles of unit density through air at 212 F when the separation factor is one thousand times gravity. By observing the rela tionship in formula [2], the entrainment velocity under any other conditions can be readily determined. It is to be noted th at the viscosity of the entraining gas varies as the square root of the absolute temperature. Table 1 illustrates the difficulty of separating single isolated particles from a large gas stream, and how this difficulty increases with decreasing particle size. In addition, it must be kept in mind that A.S.M.E. BOILER CODE Interpretations THE Boiler Code Committee meets monthly for the purpose of con sidering communications relative to the Boiler Code. Any one desiring infor mation on the application of the Code is requested to communicate w ith the Secretary of the Committee, 29 West 39th St., New York. The procedure of the Committee in handling the cases is as follows: All inquiries must be in written form before they are accepted for consideration. Copies are sent by the Secretary of the Committee to all of the members of the Committee. The interpretation, in the form of a reply, is then prepared by the Committee and passed upon at a regular meeting of the Committee. This inter pretation is later submitted to the Coun cil of The American Society of Mechani cal Engineers for approval after w hich it is issued to the inquirer and published in M echanical E n g in e e r in g . Following are records of the interpre tations of this Committee formulated at the meeting of December 6 , 1935, and approved by the Council. Case N o. 756 and Case N o. 757 (Annulled) Case N o. 808 (Interpretation of Par. H-24) Inquiry: (a) May the provisions of Par. P-216 be applied to heating boilers as an extension of the provisions of Par. H-24? (b) In the case of welded low-pressure heating boilers having unflanged heads, may the provisions of Par. H-24 be applied? If not, w hat wohld the re quirements be w ith respect to the area to be stayed and what would be the maximum height of the segment above the tubes? Reply: (a) The provisions of Par. P-216 may be applied to the design of low-pressure heating boilers having flanged heads. (J>) Excepting only the allowance of February, 1936 2 in. above the tubes, the provisions of Par. H-24 may not be applied to the unflanged flat heads of welded heating boilers w ith the exception th a t unflanged flat heads inserted in the shell at least flange which is screwed over the end of a shell, pipe, or header be considered acceptable under the rules in Par. P-198? (J>.) Will a head of this type be subject to the limit of 100 lb per sq in. working She// ?-- ^ She// j She// A ! Head GO Head CO HO. 31 H ead CO 3/ (see Fig. 3l( )) may be considered the equivalent of flanged heads (t = shell thickness). For flat unflanged heads not inserted in the shell (see Figs. 3 1 and (()), the maximum distance from the top row of tubes to the shell must not exceed If without staying. Case N o. 813 (.Interpretation of Pars. P-198a and P-268a) Inquiry: (a) Will a flat head having a pressure specified for threaded joints in Par. P-268? Reply: (a) Flat heads attached in the manner described may be considered equivalent to either sketch (/) or (f) of Fig. P-14 V2 provided all other require ments thereof are m et and all possible means of failure of the threaded joint, either by shear, tension, or compression, due to the hydrostatic end force, are resisted w ith a factor o f safety of five. The limitation referred to in Par. P-268 is not intended to apply to 129 threaded joints not connected to external piping. Case N o, 814 CInterpretation of Pars. U-69 and U-70~) Inquiry: Do the plate-thickness limi tations of IV 2 in. in Par. U-6 9 , and 5/a in. in Par. U-70 apply to all plates that make up the heads and shell of the vessel, or do they apply only to the shell thickness? Reply: It is the opinion of the Com mittee that the plate-thickness limita tions of Pars. U-69 and U-70 apply to shell plates, also to heads when fabricated of more than one piece. They do not apply to heads formed from a single plate. Case N o. 810 (Annulled) Case No. 815 and Case N o. 816 (In the hands of the Committee) REVIEWS OF BOOKS A n d Notes on Books Received in the Engineering Societies Library Reducing Industrial Power Costs Reviewed by H . D rake Harkins1 Re d u c in g I n d u s t r ia l P o w e r C osts. By David Moffat Myers. McGraw-Hill Book Company, Inc., New York, 1935- Cloth, 57s X 9 in., 378 pp., 35 figs., supp. plate, $4. AS stated by the author, "the object of this book is to give the business and industrial executive unprejudiced infor mation of the kind he wants and needs, virtually, a short intensive course on industrial steam and power engineering from the economic viewpoint." The author has ably reached his objective but this reviewer questions if any appreciable number of industrial executives can be persuaded to read its 366 pages. Indus trial power engineers might well exert 1Industrial Engineer, E. I. du Pont de Nemours & Co., Wilmington, Del. Mem. A.S.M.E. some effort to persuade them to do so. Failing this, they can make good use of the book by using it as a reference work for preparing and presenting "dollar arguments" to management. Likewise, the recent engineering graduate (and some not so recent) should read this book to learn the proper balance between tech nology and the dollar in every-day engi neering work, as it is set forth emphati cally in every page of this book. Chapter 24 is devoted to power facts and data and makes interesting reading for the power engineer. The author shows by comparison and by statistics, that power cost, although relatively an unimportant part of industrial total cost, is a very important part of net profit even in prosperous years. Unfortunately, this important relation is also borne by pack aging, advertising, and so many other industrial costs that we may doubt that it w ill do much to impress management. This reviewer finds management easier to convince by the argument th at profits made in the power plant continue through good years and bad and are rela tively independent of sales effort, changes in style, and buying habits and the other adverse factors which affect the sale of commodities. The author has included a chapter put ting " hydro" in its proper place. The author has wisely included his power-loss check chart because the book would not be complete without it, al though this material has been published before. In his attempt to simplify steam-powerplant engineering for the.nontechnical reader, the author has done an excellent job but occasionally permits his own technical knowledge to lead him away from th at reader's viewpoint. For ex ample, he might have spared those read ers some of our technical idiosyncrasies, especially " equivalent evaporation" and "factor of evaporation." Boiler effi ciency can be explained without these terms. February, 1936 129 2 in. above the tubes, the provisions of Par. H-24 may not be applied to the unflanged flat heads of welded heating boilers w ith the exception th at unflangcd flat heads inserted in the shell at least flange which is screwed over the end of a shell, pipe, or header be considered acceptable under the rules in Par. P-198? (b) Will a head of this type be subject to the lim it of 100 lb per sq in. working S he// Head Head W FIG. 31 31 (see Fig. 3 1 ) may be considered the equivalent of flanged heads (t = shell thickness). For flat unflanged heads not inserted in the shell (see Figs. 3 1 and (c'j), the maximum distance from the top row of tubes to the shell must not exceed l j without staying. Case No. 813 (Interpretation of Pars. P-19Sa and P-268a~) Inquiry: (a) Will a flat head having a pressure specified for threaded joints in Par. P-268? Reply: (a) Flat heads attached in the manner described may be considered equivalent to either sketch (c) or (j) of Fig. P-14V2 provided all other require ments thereof are met and all possible means of failure of the threaded joint, cither by shear, tension, or compression, due to the hydrostatic end force, are resisted w ith a factor of safety of five. The limitation referred to in Par. P-268 is not intended to apply to C / threaded joints not connected to external piping. Case No. 814 (Interpretation of Pars. U-69 and U-70') Inquiry: Do the plate-thickness limi tations of l 1/* in. in Par. U-69, and y 8 in. in Par. U-70 apply to all plates that make up the heads and shell of the vessel, or do they apply only to the shell thickness? Reply: It is the opinion of the Com mittee that the plate-thickness limita tions of Pars. U-69 and U-70 apply to shell plates, also to heads when fabricated of more than one piece. They do not apply to heads formed from a single plate. Case No. 810 (Annulled) Case N o. 815 and Case N o. 816 (In the hands of the Committee) REVIEWS OF BOOKS A nd Notes on Books Received in the Engineering Societies Library Reducing Industrial Power Costs Review ed by H . D rake H arkins1 R e d u c in g I n d u s t r ia l ' P o w e r C osts. By David Moffat Myers. McGraw-Hill Book Company, Inc., New York, 1935. Cloth, 57/s X 9in., 378pp., 35 figs., supp. plate, $4. AS stated by the author, " the object of this book is to give the business and industrial executive unprejudiced infor mation of the kind he wants and needs, virtually, a short intensive course on industrial steam and power engineering from the economic viewpoint." The author has ably reached his objective but this reviewer questions if any appreciable number of industrial executives can be persuaded to re ad its 366 p ag es. In d u s trial power engineers might well exert 1Industrial Engineer, E. I. du Pont dc Nemours & Co., Wilmington, Del. Mem. a .s .m .e . some effort, to persuade them to do so. Failing this, they can make good use of the book by using it as a reference work for preparing and presenting "dollar arguments" to management. Likewise, the recent engineering graduate (and some not so recent) should read this book to learn the proper balance between tech nology and the dollar in every-day engi neering work, as it is set forth emphati cally in every page of this book. Chapter 24 is devoted to power facts and data and-makes interesting reading for the power engineer. The author shows by comparison and by statistics, that power cost, although relatively an unimportant part of industrial total cost, is a very important part of net profit even in prosperous years. Unfortunately, this important relation is also borne by pack aging, advertising, and so many other industrial costs that we may doubt that it will do much to impress management. This reviewer finds management easier to convince bv the argument that profits made in the power plant continue through good years and bad and are rela tively independent of sales effort, changes in style, and buying habits and the other adverse factors which affect the sale of commodities. The author has included a chapter put ting "hydro" in its proper place. The author has wisely included his power-loss check chart because the book would not be complete without it, al though this material has been published before. In his attempt to simplify steam-powerplant engineering for the .nontechnical reader, the author has done an excellent job but occasionally permits his own technical knowledge to lead him away from that reader's viewpoint. For ex ample, he might have spared those read ers some of our technical idiosyncrasies, especially "equivalent evaporation" and "factor of evaporation." Boiler effi ciency can be explained w ithout these terms. 130 M echanical Engineering Key to E co n o m ic Progress I n co m e a n d E conomic P rogress. By Harold G. Moulton. Brookings Institution, Wash ington, D. C., 1935. Cloth 5l/i X 8 in., 192 pp,, $2. Rev iew ed by F ra nk Clay Cross2 THE Brookings Institution, Washing ton, D. C., which the author of the book under review serves as president, was organized to conduct economic and governmental research. It is a non profit corporation devoted to public ser vice, and is financed largely through grants from philanthropic trusts. The Maurice and Laura Falk Foundation, of Pittsburgh, Pa., provided the funds for a study of income and economic progress which has just been completed after three years of investigation, and which has provided material for three books al ready published, "America's Capacity to Produce," " America's Capacity to Conserve," and "The Formation of Capital." This study began w ith a comprehensive survey of America's productive capacity. The purpose of the survey was not to esti mate w hat production might become under some fanciful system but the practi cal possibilities under present techniques. The second phase of investigation had to do w ith consumption habits, trends, and possibilities; the third, w ith the processes whereby more factories and other plants and equipment are financed from savings; the fourth, which com pleted the work, w ith the question of how the distribution of income is related to the rate of economic progress. The chief impediment to the nation's economic progress j the Brookings report declares, is to be found in the growth of measures and policies which have ham pered the free functioning of the competi tive system. In the past half century, a definite tendency has arisen to protect business enterprises by stabilizing the price structure. Corporate consolida tions, pools, trusts, cartels, and trade associations have been established to hold competition in check. Then came the NRA which undertook, through Code Authorities, to maintain certain price levels by the force of public opinion. This active philosophy, the Brookings economists believe, is responsible, in no small measure, for the difficulties which business and industry have experienced in recent years. "Particularly since the World War, and often w ith the assistance of governments," the report asserts, "efforts have been going forward to `sta bilize' existing business situations and to 2 Denver, Colo. underwrite the prosperity of individuals, corporations, or large business groups by attempting to stabilize prices. We be lieve the evidence is clear th at such at tempts, however well intentioned, are dangerously short-sighted. They result inevitably in `freezing' situations which in the interest of economic progress must be left as fluid as it is possible to make them ." The way forward suggested by the study is indeed a very simple one when compared w ith many of the intricate, or radical, schemes which have been pro mulgated. It is simply a return to wholesome competition. To reestablish that condition the first move must be to eliminate all the devices and agencies which have been created to maintain the status quo, and to make lower prices-- not higher--the goal of business and industry. The conclusion is reached that the key to economic progress is to be found in long-term reduction of prices, as technological advance makes it possible. The force to insure the reduction is com petition. The efforts of certain groups to obtain the benefits of improved efficiency in higher wages have resulted in economic disparities which arbitrary wage in creases unavoidably create between urban and rural groups. These disparities are not alone the misfortune of the agricul tural communities; their effect is adverse to all industry. The survey significantly points out that 40 per cent of the entire population of America lives either on farms or in towns of less than 2500 in habitants. If these potential buyers are to have their purchasing power aug mented as productive efficiency is in creased, they must get it through lower prices. Another large group which falls out side the wage group and hence must re treat before any artificial increase in prices is made up of small shopkeepers, professional men, and various other workers who number approximately twenty million. The fallacy of curtailing production by the establishment of quotas, the restric tion of working hours, or the control of new capital development is also clearly revealed. Whatever may be said in favor of such measures as a means to meet tem porary emergencies, the report declares, in the end they can only lead in the direc tion of national impoverishment. Even in the boom years, preceding 1929, mil lions of American families were undersup plied w ith goods. More than 16 million families had incomes of $2000 or less; six million received less than $1000. That these families wanted more goods than they were able to buy at prevalent prices is hardly open to question. The popular notion th a t the problem, can be solved by bonuses, doles, or any other government largess, or by shorter hours of labor which would distribute more money to more workers w ithout a corresponding increase in production, confuses money income w ith real income. Money is valueless except as it represents property and merchandise to supply the needs and desires of its possessors. There never has been a state of over production in America. On the con trary, production has never equaled the needs and desires of the entire population. The trouble has been a m atter of distri bution. In lucid terms the report shows that the proposal to shorten hours of labor in proportion to increases in man-hour efficiency, if carried into effect, would definitely prevent any future improve ment in the standard of living. The proponents of the plan argue th at since production per worker increased about 71 per cent in the 14 years between 1919 and 1933, work which required about 52 hr to complete in 1919 can now be done in 30 hr or less. Therefore the universal 30-hr week is advocated to relieve present unemployment. "T he adoption of such a principle," the Brookings economists declare, " would mean a freezing of standards of living in general at 1919 levels." On the basis of present prices the total national production in 1919 was considerably less in per capita terms than the low production of 1934. The pro gram thus calls specifically for a level of national production not only below th at in the boom year, 1929, but also below that obtaining in the depression period. When carefully analyzed, it says to labor: "You can reap henceforth no advan tage from technological progress, other than greater leisure; ypu shall have no choice as between more goods and ser vices and more spare time; only in so far as you may be able to obtain a larger share of a fixed total of w ealth produced will it be possible for you to enjoy more of the material comforts and conveniences of life." The unsoundness of the proposal for shorter hours of labor as an impetus to stable economic progress is identical with the fallacy that underlies all other plans to establish prosperity by such methods as bonuses to soldiers, and pen sio n s fo r th e aged--provided th e y cease to work. The proponents of such plans see more money in circulation through trade channels, constituting a greater market demand for new production. February, 1936 131 They do not see th at the production of eoods to meet the new demand would be curtailed by the very measures which would increase the monetary income. In a similar way the successful achieve ment of any program, sponsored by farm organizations or business groups, to ob tain a higher money income by selling less goods a t higher prices can only re duce the aggregate real income of the nation. Among the other popular schemes to correct economic maladjustment,, which are analyzed by the Brookings study, is the "share the w ealth" proposal. It is shown, first, th a t any attempt, short of communism, to equalize the ownership of wealth would be entirely futile. Only a small fraction of our national w ealth is actually divisible. The greater part consists of such property as railway tracks, telephone lines, power and gas plants, factories, warehouses, pipe lines, mines, and office buildings. If any di vision were to be made of such properties it would have to be accomplished through the distribution of shares of stocks which could be done only under a form of government far different from ours of today. The equalization of incomes would be equally impracticable. Those who ad vocate such a plan erroneously maintain that poverty could be relieved by utiliz ing the salaries of corporation officials and the income derived from investments, for the benefit of the masses. The amount available for distribution under such a plan, the report points out, would be less than 18 billion dollars, which would amount to about $140 per year per capita. There is just one logical way to insure prosperity, and th at is to adopt a policy which w ill enable more people to pur chase more goods, and simultaneously promote the production of more goods for them to buy. The solution of the problem, the Brookings economists as sert, is the steady lowering of prices as increased productive efficiency makes it possible--a recommendation which takes direct issue w ith much of the economic philosophy now current. Such a program would naturally en counter few, if any objectors among the consumer class. There is a widespread belief among producers, however, that profits vary directly w ith prices, and hence th at a decrease in prices would mean a decrease in earnings. The his tory of business enterprise disproves that theory, according to the Brookings study. In every instance where prices have been reduced progressively as tech nological improvements were made, profits, for business as a whole, have taken care of themselves. The two decades between 1870 and 1890 are cited as a period of rapid technological ad vance in which wholesale prices and transportation rates were greatly re duced w ithout impairing profits. Be tween 1922 and 1929, however, the story was different. In the latter period effi ciency, as measured by the productive ability of the individual worker, in creased about 18 per cent in all industry, and about 25 per cent in manufacturing. The prices of manufactured goods, how ever, declined only about 5 per cent, and the prices of raw materials remained practically stationary. Lower prices would automatically ac celerate buying, and greater production would be necessary to meet the new de mand. It is a well-known industrial principle that the unit costs of produc tion vary inversely w ith the volume of goods produced. There has never been a time in Ameri ca's economic history when the needs and desires of the population for the goods of industry did not far exceed pro duction. Yet, even in prosperous 1929, 20 per cent of the nation's plant ran to waste for lack of market. The explana tion of that fact, according to the Brookings report, lay simply in the fail ure of industry to pass along the savings of efficiency to consumers in lower prices. This process is supposed to be automatic under capitalism, but its operation has been artificially blocked to such an ex tent that our whole economic structure has become impaired. If prices had declined w ith the increase of industrial efficiency, between 1922 and 1929, the new market for goods among consumers in the lower-income brackets would have necessitated the construction of new factories and other plants to keep production apace w ith demand. More labor would have been needed to man them; more raw materials would have been required. Thus money, in the form of wages to workers and disbursements to the producers of raw materials, would have gone into the pockets of more and more potential consumers. Since con sumer demand was insufficient, however, additional plants became unprofitable. Hence savings went into speculative bid ding-up of outstanding securities and other property. The balance between production and consumption was far out of adjustment. The real income of the nation is its production. Money is merely a symbol. A program of lower prices, according to the Brookings study, would inevitably result in a greater demand for goods. This greater demand would speed the wheels of industry. Profits would in crease proportionately. More workers would be needed in factories, and in all branches of the production of raw mate rials, mining, lumbering, farming, etc. The benefits would be limited to no one group or class, but every one would share them; and the nation could look forward to a consistent and healthy growth in every division of its economic structure. Books Received in Library A erodynam ic T h eory , a General Review of Progress under a Grant of the Guggenheim Fund for the Promotion of Aeronautics. Vol. 5, Div. N-O. Edited by W. F. Durand. Julius Springer, Berlin, 1935. Cloth, 6 X 9 in., 347 pp., diagrams, charts, tables, 20 rm. (15 rm. to U. S. A.) The treatise of which this volume is a part, is intended to provide the aeronautic designer and student with a reasonably adequate presentation of back ground theory. The first of the two mono graphs presented is the "Dynamics of the Airplane," by Professor B. Melvill Jones. It is chiefly devoted to a discussion of the experi mental data, symbolic analyses, and numerical computations that are required for the study of small disturbances from straight flight. The second monograph, by L. V. Kerber, dis cusses various methods for estimating the performance of airplanes, or the consequences of changes in their design, prior to their con struction. A.S.T.M. Stan d a rd s o n T e x t il e M aterials, prepared by Committee D-13 on Textile Mate rials, Specifications, Tolerances, Methods of Testing, Definitions and Terms. American Society for Testing Materials, Philadelphia, October, 1935. Paper, 6 X 9 in., 246 pp., illus., diagrams, charts, tables, $1.50. This pamphlet contains all of the specifications and tests approved by the American Society for Testing Materials, together with other infor mation of use to users of textile materials. The book includes various new and recently revised standards, some of which are pub lished for the first time. A n a ly tica l a n d A p p l ie d M echanics. By G. R. Clements and L. T. Wilson. McGrawHill Book Co., New York and London, 1935. Cloth, 6 X 9 in., 420 pp., diagrams, charts, tables, $3.75. This text aims to provide a simple but rigorous discussion of the mathe matical theory necessary for a thorough first course in mechanics, and to present a wide variety of applications, interesting in them selves, and of direct usefulness to students of engineering. Both graphical and analytical methods are discussed. Many problems are provided. DAMPFTURBINBNKRAFrWBRKB K lEINER UND M ittlerer L e ist u n g . By F. Aschner. Julius Springer, Berlin, 1935. Cloth, 6 X 9 in., 145 pp., diagrams, charts, tables, 9 rm. The c o n s tr u c tio n o f s te a m - tu rb in e e le c tric p la n ts IS here considered with reference to the require ments of the smaller installations, with generating units up to 5000-kw capacity. Attention is paid to economic and mechanical questions, to boiler and turbine equipment, costs, and operating costs. 132 M echanical Engineering H istoire de la L ocomotion T errestre. Les Chemins de Fcr. Texte et Documentation. By C. Dollfus and E. De Gcoffroy. Villustration, 13 rue Saint-Georges, Paris, 1935. Leatlicr, 11 X 15 in., 376 pp., illus., maps, charts, diagrams, 195 fr. To celebrate the centennial of the first European railway system, VIllustration has issued a handsome folio, describing the development of the rail road from its beginnings to the present day. An outstanding feature of the work is the illustrations, numbering several hundred and including many in color. These comprise re productions of contemporary drawings and photographs and give a vivid picture of de velopments. The book will delight every student of railroad development. Introduction to Atomic Physics. By J. Thomson. Methuen and Co., London, 1935Cloth, 6 X 9 in., 228 pp., diagrams, charts, tables, 10s 6d. The author has endeavored here to supply a concise, logical account of the fundamental facts and theories of the subject, which will give the reader a clear idea of the essential simplicity of atomic phe nomena and show in proper perspective the new principles that modem investigations have brought into being. The more important experiments which form the basis for the various theories are first described. This is followed by a summary of Bohr's conceptions and an account of elementary wave mechanics. There is a final section which applies the theory to questions of atomic, nuclear, and molecular radiation. Introduction to the T heory of Functions or a Complex Variable. By E. T. Copson. Clarendon Press, Oxford, England, Oxford University Press, New York, 1935. Cloth, 6 X 9 in., 448 pp., charts, diagrams, tables, $8.50. This text, which is based on a course of lectures given to undergraduates at the universities of Edinburgh and St. Andrews, is intended to provide an easy introduction to the methods of the theory of functions of a complex variable. The first six chapters contain an exposition of the properties of one valued differentiable functions of a complex variable. In the rest of the book the problem of conformal representation, the elements of the theory of integral functions, and the be havior of some of the special functions of analysis are discussed. J. & E. H all, Ltd., 1785 to 1935- By E. Hesketh. University Press, Glasgow, 1935Cloth, 6 X 9 in., 58 pp., illus., diagrams. The former chairman of this firm has written a brief account of its history. Founded in 1785, it was a pioneer in the manufacture of paper-making machinery, marine engines, and refrigerating machinery. Richard Trevithick was employed at these works during the clos ing period of his life. The little book is attractively printed and contains a number of interesting illustrations. Machinery's Yellow-Back Series. Ma chinery, 148 Lafayette St., New York, 1935Paper, 5Vs X 8V2 in., 14 to 22 pp., illus., diagrams, charts, tables, $0.15 each; 8 for $1. This scries comprises fifty pamphlets, each of which discusses a specific topic of interest to machinists and mechanical engineers. Each pamphlet presents the essential facts in a con cise statement, usually about fourteen pages long. The information is specific and prac tical, and in many cases is not easily available elsewhere. A wide scope is covered, including advice on electric motors, change gears, pat ents, plastics, steels, welding, brazing, bear ings, and many other subjects. M aterials T esting, Theory and Practice. By I. H. Cowdrey and R. G. Adams. Second edition. John Wiley & Sons, Inc., New York, 1935- Cloth, 6 X 9 in., 144 pp., illus., diagrams, charts, tables, $1.75. This book is intended to provide those taking a labora tory course in the study of materials under stress with a discussion of the methods com monly used for testing and of the fundamental principles involved. Basic methods of attack and interpretation are indicated. The new edition has been brought up to date, and a chapter on the testing of concrete added. T he Metal--Iron. (Alloys of Iron Re search, Monograph Series.) By H. E. Cleaves and J. G. Thompson. Published for the Engineering Foundation by McGraw-Hill Book Co., New York, 1935- Cloth, 6 X 9 in., 574 pp., illus., diagrams, charts, tables, $6. This monograph is the fifth of the series pre pared by the Alloys of Iron Research. It pro vides a review of the available information on the preparation and properties of metallic iron of high purity. It therefore supplies the best approximation of the properties of pure iron that can be presented and is a basis for the other monographs in the series. An exten sive select bibliography, containing over one thousand references, is included. M olybdenum Steels, Their Manufacture and Application. By J. L. F. Vogel and W. F. Rowden. High-Speed Steel Alloys Ltd., Widnes, England, 1935. Leather, 7 X 10 in., 103 pp., illus., diagrams, charts, tables, 5s. This publication discusses the manufac ture of molybdenum steel, its properties, work ing and heat-treatment, and the uses of the various types. Praktischb Physik. By F. Kohlrausch. Seventeenth edition. Edited by F. Henning. B. G. Teubner, Leipzig and Berlin, 1935. Cloth, 6 X 9 in., 958 pp., diagrams, tables, charts, 32 rm. (25 per cent discount in U. S. A.) Kohlrausch's " Lehrbuch" has long been the standard treatise on physical-labora tory methods and measurements, and this new edition will be welcomed by physicists gen erally. The book has been thoroughly re vised by a group of specialists under the direc tion of Dr. F. Henning, of the PhysikalischTechnische Reichsanstalt, and has been en tirely reset. Additional tables and illustra tions have been added and the book is some what larger than before. Those who are engaged in research work in pure or applied physics will find the work a valuable reference book. P reparation of E ngineering R eports. By T. R. Agg and W. L. Foster. McGrawHill Book Co., New York and London, 1935. Cloth, 5 X 8 in., 192 pp., charts, diagrams, tables, $1.75. The beginner in report writing will find this work a help in presenting his material in an orderly way. The collection of the data, the arrangement of the subject matter, style, illustrations and Other practical questions are discussed in a satisfactory way. Press W ork Pressures. By C. W. Lucas. McGraw-Hill Book Co., New York and London, 1935. Cloth, 8 X 11 in., 128 pp., diagrams, tables, $4. This volume presents the results of over one thousand tests of the pressures necessary for various operations, and is intended to guide the engineer in estimating the size of press required for a given job. The information is classified according to the operation, material, shape, and size of piece and is presented clearly and concisely. Coin ing, drawing, embossing, forging, seaming, curling, punching, cutting, and riveting opera tions are included. Schweizerischer Verband fr die Material prfungen der Technik (S.V.M.T.) Associa tion Suisse pour l'Essai des Matcriaux (A.S.E.M.) Diskussionsbericht Nr. 31. Struc t u r e A n ATOMIQUE ET VALEUR TECHNIQUE DU Bois. By P. Jaccard. Zurich, Switzerland, Dec., 1934. Paper, 8 X 12 in., 27 pp., illus., diagrams, charts, tables. Professor Jaccard in this book gives a report of the results of his studies of the anatomical characteristics of wood and their influence upon its engineering value. Schweizerischer Verband fr die Material prfungen der Technik (S.V.M.T.) Association Suisse pour l'Essai des Materiaux (A.S.E.M.) Diskussionsbericht Nr. 30. V erleim technik m it K nochen- u n d L ed er leim ; Spannungs f r e ie H o lztro c k n u n g . Zurich, Switz., Dec., 1934. Paper, 8X 1 2 in., 28 pp., illus., charts, tables. The first of these two reports discusses methods of testing bone glue and leather glue, and their proper use. The second discusses the kiln drying of lumber. Science Museum (South Kensington). Handbook of the Collections illustrating M arine Engines, History and Development. By G. L. Overton. His Majesty's Stationery Office, London, 1935. Paper, 6 X 10 in., 96 pp., illus., 2s. This pamphlet, as a recent addition to the valuable series of guidebooks issued by the Science Museum, sketches the history and development of marine engineer ing. Early efforts in steam propulsion and the development of paddle, screw, and internalcombustion engines and steam turbines, of boilers and propellers are outlined and illus trated from the museum collections. Sky' H igh, the Story of Aviation. By E. Hodgins and F. A. Magoun. Little, Brown and Co., Boston, 1935. Cloth, 6 X 9 in., 414 pp., illus;, $2.75. An excellent popular history of man's efforts to conquer the air. The work was first published in 1929 and is now brought up to date by the inclusion of , the important achievements of the past six years. The book is readable and accurate. Steam Plant Operation. By E. B. Wood ruff and H. B. Lammers. McGraw-Hill Book Co., New York and London, 1935. Cloth, 6 X 8 in., 368 pp., illus., diagrams, charts, tables, $3. This book is intended to provide a working knowledge of the fundamental principles of stationary engineering. Ap proved methods of operating all the equip ment usually found in power plants are de scribed, and rules of procedure are outlined. Technical and practical information are com bined in a useful way and presented with clearness, to form a very satisfactory textbook. T echnical Aerodynamics. By K. D. Wood. McGraw-Hill Book Co., New York and London, 1935- Cloth, 6 X 9 in., 330 pp., diagrams, charts, tables, $3.50. Intended for students preparing for the design and manu facture or a irc ra ft, th is b o o k aim s t o p ro v id e a simple, practical text on airplane perform ance and stability calculations. Funda mental principles are emphasized rather than technical details of construction and opera tion. WHAT'S GOING ON Including News of A.S.M .E. Affairs This M onth's Authors READERS of M echanical Engineering Deed no introduction to the four dis tinguished engineers whose addresses at the Watt Bicentenary are published in this issue. Geo. A. O rrok, consulting engineer, mem ber, A.S.M.E., whose engineering experience covers the entire history of the electric-light ing industry, designed some of the largest and most modern steam engines ever used for the generation of electrical energy, at a time when the reciprocating engine was still undisputed in this field. Joseph W. R oe, professor of industrial en gineering at New York University, member, A.S.M.E., is well-known as a student of the history of engineering and biographer of engineers. His "Early English and American Tool Builders" remains an authority on this subject. Dexter S. Kimball, Dean of Engineering, Cornell University, past-president, A.S.M.E., himself designed and erected, for the Union Iron Works, some of the unusual steam engines described and illustrated in his address. W. L. Batt, president, SKF Industries and president, A.S.M.E., has had that close con tact with and responsible charge in industrial affairs that gives his appraisal of the many sources of Watt's greatness a real and modern meaning. Ch a r le s E. L u c r e , head of the department of mechanical engineering, Columbia University, consulting engineer and member, A.S.M.E., is a specialist in thermodynamics and steam and gas power, and author of textbooks on power engineering. Alpred L. Webrb, member A.S.M.E., engi neer with the U. S. Pipe & Foundry Co., Burlington, N. J., writes on "Formation and Growth of Sugar Crystals in Vacuum Pans." Mr. Webre has been identified for the past thirty years with the sugar industry as de signer of evaporators, vacuum pans, and heaters. He is the author of a textbook entitled "Evaporation" as well as many papers and bulletins on related subjects, pre sented before groups of sugar technologists. Theodore H atch, instructor in industrial sanitation, Harvard Engineering School and Harvard School of Public Health, lectures on the engineering aspects of problems in indus trial-disease control. He has done consider able work in research on dust, its properties, production in industry, control; in the de velopment of sampling instruments and meth ods of measuring dust concentrations and size f dust particles, in the study of exhaust hoods and air-cleaning equipment, and in the design of dust-control systems for granite cutting and the pulverizing, mining, and hard-rock indus tries. H enry D. Sayer, auchor of the paper "Occupational Diseases" and who is associated with the Association of Casualty and Surety Executives was former Industrial Commis sioner of New York State. Warren A. Cook, who writes on "Engi neering Control of Occupational-Disease Haz ard," is industrial hygienist of the Bureau of Occupational Diseases, . Connecticut State Department of Health, Hartford. From 1925 to 1928 he was engaged in occupationaldisease prevention for the Travelers Insurance Company. For the past seven years he has been in charge of the technical work of occu pational-disease control in the Connecticut Health Department. Another in the series of reviews of current economic topics of unusual interest to mechani cal engineers is "Planning--Three View points," contributed by B. Alden Thresher, a member of the Department of Economics, Massachusetts Institute of Technology. Activities of A.S.M.E. Executive Committee AT a meeting of the Executive Committee of The American Society of Mechanical Engineers, held on January 4,1936, the follow ing actions of general interest were taken. PROGRAM FOR 1936 In a discussion of the items on which prog ress should be made during the administra tive year it was voted to authorize the presi dent to appoint a committee to study the relationships between the local sections of the Society and the various local engineering societies. vice-presidents designated as councilors Mr. Batt reported that the seven vicepresidents had been designated as the coun cilors for the seven geographical districts of the country in accord with the action of the Council at St. Louis and that a letter was being sent to the sections asking their co operation. He has asked each of the seven councilors to have a report for each meeting of the Executive Committee. certificates of in d eb ted n ess It was reported that $5000 of the issue of the Certificates of Indebtedness to members of the Society had been retired. Roy V. Wright, Erik Oberg, and W. D. Ennis were elected as the trustees of the fund. DATE OF DALLAS MEETING It was voted to setJune 15 to 20,1936, as the date of the Dallas Meeting of the Society. 133 BOILER-CODE APPOINTMENTS Upon recommendation of the Special Com mittee on Boiler Code, the Executive Com mittee authorized the appointment of sub committees on Ferrous Materials and Nonferrous Materials, as follows: Subcommittee on Ferrous Materials: H. LeRoy Whitney, chairman, A. J. Ely, H. J. French, H. W. Gillette, J. J. Kanter, H. J. Kerr, A. B. Kinzcl, and A. E. White; Subcommittee on Nonferrous Materials: H. B. Oatley, Chairman J. J. Aull, D. K. Crampton, A. M. Houser, F. P. Huston, H. C. Jennison, E. F. Miller, and Joseph Price. The Executive Committee of Council authorized the appointment to the Main Boiler Code Committee of H. C. Boardman and W. G. Hampton. CALVIN W . RICE MEMORIAL COMMITTEE Upon the recommendation of the Calvin W. Rice Memorial Committee, the Executive Committee voted to assign to the Committee on Meetings and Program the responsibility for the administration of the Calvin W. Rice Memorial Lecture. HALSEY BEQUEST The Secretary reported that Frederick A. Halsey, member of the A.S.M.E., who died October 20, 1935, bequeathed the Society the following four books: Reuleaux' "Kine matics of Machinery," translated and edited by A. B. W. Kennedy; "Principles of Mecha nism," by Willis; "Rumford's Essays," three volumes; "Metric System," by Davies. The Secretary was asked to express the apprecia tion of the Society and to place the books in the Engineering Societies Library. COURTESIES FOR I.C .E . A communication from the secretary of the Institution of Civil Engineers, London, offering the courtesy and privileges of the Institution to accredited visitors was re ceived and acknowledged with appreciation. It reads: "The President and Council of The Institution of Civil Engineers have directed that a letter be addressed to kindred En gineering and Scientific Societies throughout the world stating that members of such Socie ties visiting this country, if suitably intro duced, will, as a matter of courtesy, be ac corded the privileges of attending the meetings of this Institution and using the Institution Library and Reading Rooms. Further, such accredited visitors will, if they desire it, be presented with letters of introduction to members of the Institution to enable them to visit engineering works in this country. Perhaps you will be so good as to take the necessary steps to make this known to the members of your Society. / 134 M echanical Engineering The Sixteenth Annual Meeting of American Engineering Council DELEGATES from the 42 member or ganizations of American Engineering Council, meeting in Washington, January and 11, discussed the growing evidence of unity in the profession as to the formulation and dis semination of opinion on matters of public affairs. The Assembly acted upon reports from sixteen major and minor committees and subcommittees of the Council, listened to stimulating addresses at the All En gineers Dinner, attended by some 450 en gineers, and left Washington with renewed expressions of the opportunities for advancing the public interest and for maintaining high professional standards through the agency of the American Engineering Council. At the morning session at the Mayflower Hotel, January 10, President J. F. Coleman opened the meeting with an address on the es sential elements in reviving the construction industry. Then followed in order a series of reports and discussions covering a wide range of subjects of timely interest to engineers. 1, with the plan of presenting the report pub licly as soon as possible thereafter as the engi 1n0eers' contribution to the national welfare. Charles W. Eliot, II, executive officer of the National Resources Committee, discussed the purposes and plans of that body in forwarding a state and local as well as a federal concept of planning. The need of approaching planning from a local and regional viewpoint was espe cially emphasized. It was voted to refer the SURVEY o r THE PROFESSION George T. Seabury, as chairman of the Engi neering and Allied Technical Committee, re ported on the "Survey of the Engineering Profession" conducted by the Bureau of Labor Statistics of the U. S. Department of Labor. His report, based on returns from more than 60,000 questionnaires, the largest survey of this kind ever conducted, indicated that the findings would tend to give direction to engi neering education, to choice and distribution of occupation, and to compensation of engineers. It is expected that full returns will be available in the early spring. It was voted to recom mend to the Executive Committee of Council that steps be taken toward private publication of a mass of detailed information to supple ment the government report. Dr. Leonard D. White, U. S. Civil Service Commissioner, discussed the needs for a widely extended civil service to include state and local governmental bodies as well as federal, in or der to uphold the professional standards of engineers in the public service, Discussion developed that classification by position is essential in the development of a suitably paid civil service. It was voted to instruct the Executive Committee to take the steps neces sary to put these basic concepts into action, especially in cooperation.with local and state engineering societies. ECONOMIC BALANCE TOWARD HIGHER STANDARDS Ralph E. Flanders presented the third progress report of the Committee on the Inter relation of Production, Distribution, and Con sumption. In 108 classified questions and answers there was presented a catechism on the engineers' concept of the possibilities of an economic balance in the interests of a high standard of living for all. T he re p o rt w as accepted with the recommendation of the com mittee that all delegates study it, secure local discussion on its major objectives and detailed recommendations, and report back February A. A . POTTER, PRESIDENT, A .E.C. bill (S. 2825) now before the Senate, providing for the continuation of the Federal organiza tion on a permanent basis, to the Public Affairs Committee of Council for recommendations. PUBLIC AFFAIRS REPORTS The Public Affairs Committee of American Engineering Council, under the chairmanship of F. J. Chesterman, of Pittsburgh, has been organized under a new plan during the past year with several subcommittees active in studying public problems which fall within the purview of the profession. For coordina tion, the subcommittee chairmen are members of the national committee and steps are being taken to make the membership of subcom mittees overlap with that of similar commit tees of national, state, and local engineering societies. As a result of this work, the re ports rendered at the annual meeting cover basic findings in a broad variety of fields. The subcommittee on the Administration of Public Works, F. M. Gunby, chairman, re affirmed Council's past position that engineer ing public works of the Federal Government, in so far as practicable, should be concentrated under one qualified head. The Water Resources Committee, headed by W. S. Conant, reiterated its belief in two fun damental needs for the formulation of a waterresources policy: (1) Complete and coordinated basic data bearing on the subject and (2) com prehensive study of water control legislation. The establishment of a body similar to the Board of Surveys and Maps of the Federal Gov ernment for the correlation of government data on water resources was recommended. As a result of the work of the Aeronautics Subcommittee, headed by Grover Loening, the Public Affairs Committee adopted a report supporting aeronautical research by the col leges, disfavoring further investigations of the industry, recommending further studies to ward the simplification of aircraft construc tion regulations, and favoring the placement of employees of the Bureau of Air Commerce under Civil Service. The Committee on Competition of Govern ment with Engineers in Private Practice, under the chairmanship of Alonzo J. Hammond, ad vocated the curtailment of competitive ac tivities by government and the raising of con sulting fees by public bodies to a basis compar able to private practice. RURAL ELECTRIFICATION R. W. Trullinger, of the U. S. Bureau of Agricultural Engineering, reported on the activities of a subcommittee, made up of mem bers of the American. Society of Agricultural Engineers, a member body of the Council, to forward the rural electrification program through the aid of engineers. It was voted that this work be continued under a com mittee which would be representative of the profession as a whole. The Assembly received a report of the Com mittee on Patents, Dean A. A. Potter, chair man, dealing with the elimination of fraudu lent practices, the use of a single signature on patent applications, the validation of joint patents, and the extension of the full rights of inventors. In addition, several specific items of legislation were presented as under con sideration by the committee. It was recom mended that the work of the committee be continued. MAPPING The Assembly adopted the recommendations of the Executive Committee that American Engineering Councilestablish anew Committee on Mapping and Surveys and that it endeavor to organize public opinion as to the basic need for completing the map of the United States. It was voted to support the original Temple Act to the end that its purposes be effectuated by appropriations which are to be based upon the fundamental values of mapping and not on a relief basis. GOOD-FELLOWSHIP DINNER The annual All Engineers Dinner of Council, held on the evening of January 10, filled the main ballroom of the Mayflower Hotel. Some 450 engineers, representing all the major branches of the profession were in attendance. Dr. Harrison E. Howe, editor, Industrial & En gineering Chemistry, proved a brilliant toast master. Following the dinner, an engrossed resolu tion was tendered to J. F. Coleman in apprecia tion for. his services as president of Council during the past two years. Dr. William Mc Clellan, president of the Potomac Electric February, 1936 135 Power Company and chairman of the Dinner Committee, made the presentation. He told jjo-vv Mr. Coleman had been successful in carrving Council through a critical period in its history. Dean A. A. Potter was introduced js the new president of the Council. He stressed the need for solidarity of engineering opinion. Dr. William F. Durand, chairman of the Third World Power Conference, past-president A.S.M.E., and John Fritz Medalist for 1935, discussed the deeper functions of the engineer. He stated that engineers are the custodians of natural resources such as minerals, coal, and oil but are not fully living up to their responsi bility in conserving these resources. The profession, he said, must concern itself not alone with technical matters but increasingly with human and social problems. Ralph E. Flanders, past-president of the A.S.M.E., directed his remarks toward a reply to a recent address by Walter Lippman before the American Medical Society. Mr. Lippman had stated that the engineer is a master of material resources but that the application of his material concepts does not work involving human problems. Mr. Flanders stated that on the contrary every phase of the engineer's work is intensely human in its application and relationships. He predicted that engineering technique will carry the nation far beyond the "miserable physical standards of 1929." The meeting was addressed also by the presi dents or secretaries of each of the seven national engineering societies holding membership in Council, and by the chairman of the Sixth Conference of the Secretaries of Engineering Societies. Those present were unanimous in affirming their support to the continued leader ship of Council as a unifying influence in engi neering affairs. NEW OMICERS Council's new president for 1936 and 1937 is Dr. A. A. Potter, Dean of the Schools of Engi neering, Purdue University, who succeeds J. F. Coleman, of New Orleans. New vice-presi dents are: Ralph E. Flanders, president of the Jones & Lamson Machine Co., for a two-year term; and J. S. Dodds, professor of Civil Engineering, Iowa State College, for a oneyear term. The chairmen of the Public Affairs Commit tee and of the Committee on Membership and Representation were made ex-officio members of the Executive Committee of Council. The present Public Affairs chairman is F. J. Chesterman. C. L. Bickelhaupt, who heads the membership group, already is a member of the Executive Committee as vice-president of Council. In addition to these, the Execu tive Committee includes Alonzo J. Hammond, vice-president, C. E. Stephens, treasurer, and William McClellan, chairman of the Finance Committee, who were re-elected. Frederick M. Feiker was re-elected as executive secretary of the Council. SECRETARIES' CONFERENCE Preceding the meeting of the Assembly of American Engineering Council, there was held onJanuary 9the Sixth Conference of Secretaries of Engineering Societies. Some thirty na tional, state, and local societies were repre Technology, Clarkson College of Technology, sented. The morning program developed the College of the City of New York, Columbia possibilities and opportunities for cooperation University, Drexei Institute, Johns Hopkins and coordination on matters of public affairs University, Lafayette College, Manhattan through state societies, national societies, and College, New York University, Newark the American Engineering Council. College of Engineering, University of Pitts Both at this session and at the subsequent burgh, Polytechnic Institute of Brooklyn, Council session on Public Affairs, the develop Princeton University, Rensselaer Polytechnic ment of local and state public affairs commit Institute, Rutgers University, Stevens Institute tees was carried forward and both meetings of Technology, Swarthmore College, Syracuse favored the further cooperation of present University, Union College, Webb Institute of organizations to develop united action in these Naval Architecture. matters. Engineers' Council for Professional Develop Speakers at the Secretaries' Conference in ment is a conference of seven engineering cluded: J. F. Coleman, on Progress in Engineer bodies concerned with the technical, educa ing Organization; General R. I. Rees, of New tional, and legislative interests of engineers. York, on Opportunities for Unity Among En Its object is to enhance the status of the engi gineering Organizations; and Col. J. M. John neer. The constituent bodies are: American son, Assistant Secretary of Commerce, on the Society of Civil Engineers, The American Engineer in Government and Business. Other Society of Mechanical Engineers, American topics included cooperation with national, Institute of Electrical Engineers, American state, and local secretaries; employment ac Institute of Mining and Metallurgical Engi tivities; engineering publicity; nontechnical neers, American Institute of Chemical Engi programs; and engineering society manage neers, Society for the Promotion of Engineer ment. ing Education, and National Council of State On adjournment of the Secretaries' Confer Boards of Engineering Examiners. By unani ence, an informal tea and reception was held mous action these organizations authorized at the home of Mr. and Mrs. F. M. Feiker in E.C.P.D. to act as an accrediting agency. This honor of Mr. and Mrs. J. F. Coleman and Dean it does through the activities and on the A. A. Potter. recommendations of its Committee on Engi neering Schools headed by Dt. Karl T. Comp Inspection and Accrediting ton, President, Massachusetts Institute of Technology. Other major committees of of Engineering Colleges Begun by E.C.P.D. E.C.P.D. give their attention to selection and guidance of prospective engineering students, further professional training of young engi T neering graduates, and the development of HE program of inspection and accrediting standards of professional recognition. Head of engineering curricula, which the quarters of E.C.P.D. are at 29 West 39th Engineers' Council for Professional DevelopS treet, New York City. Charles F. Scott is ment offered last year to schools granting chairman and George T. Seabury, secretary. engineering degrees, has been accorded a hearty response by 34 colleges and universities in the New England and the Middle Atlantic A .M .A . to Discuss Industrial States. Inspections in these two regions were inaugurated late in 1935 and will be actively Relations Problems continued during the next few months. When substantial progress,has been made in these areas, it is expected that the program will be extended to engineering schools throughout the United States. The accredit ON February 5, 6, and 7, 19.36, the Ameri can Management Association will hold a conference "on "Today's Major Personnel Problems" at the Palmer House in Chicago. The conference is one of the usual meetings of ing program has for its purpose the best development of engineering education by identifying those institutions that offer engi the Personnel and of the Office Management Divisions of the Association. This year the Industrial Relations Association of Chicago is neering curricula worthy of recognition as cooperating. such. The second objective is to build up a The meeting promises to be of unusually list of accredited engineering schools, which great interest because of the problems of man it is hoped may be uniformly adopted by agement that face American business execu educational, technical, and state organizations tives under recovery conditions and under the now using dissimilar lists. new Federal laws. Institutions in the New England States Among the speakers will be: Tom Girdler, that have applied for accrediting are: Brown chairman of the Board, Republic Steel Cor University, Dartmouth College (Thayer School poration; Dean William H. Spencer, School of of Civil Engineering), Massachusetts Institute Business, University of Chicago; M. B. of Technology, Northeastern University, Nor Folsom, treasurer, Eastman Kodak Company; wich University, Rhode Island State College, J. Douglas Brown, director, Industrial Rela Tufts College of Engineering, University of tions Section, Princeton University; S. F. Maine, University of New Hampshire, Uni Shattuck, vice-president, Industrial Relations, versity of Vermont, Worcester Polytechnic Kimberly-Clark Corporation; and other execu Institute, and Yale University. tives of the very large and of smaller com In the Middle Atlantic States the following panies. James O. McKinsey, chairman, Mar schools have applied: Alfred University, shall Field & Company, will preside at the Bucknell University, Carnegie Institute of dinner meeting. 136 M echanical Engineering 1935 Census of Business MECHANICAL - engineering firms are among the business-service groups being included in the Census of Business, which be ganJanuary 2,1936, covering the calendar year 1935. Other groups in the business-service field to be included are architects, civil engi neers, accountants, advertising counselors, statistical reporting services, public-relations counselors, and sales consultants. These professional groups have a vital part in modern business, hence their inclusion in this broad measurement of American business. All mechanical-engineering firms will be canvassed for reports on their 1935 operations. The inforfnation will include legal form of organization, number of active proprietors and firm members, paid employees and pay rolls, receipts in 1935, and other supplemental facts. Whereas the first census comparable to the present project, covering 1929, was limited primarily to the distribution field; and the second project, the Census of American Busi ness for 1933, was limited to distribution, service businesses, amusement enterprises, and hotels; the 1935 Census of Business will cover the following fields: retail trade, wholesale trade, insurance, real-estate, construction, banking, finance, ' business services, broad casting, advertising agencies, hotels, amuse ments, distribution of manufacturers' sales, trucking, warehousing, bus transportation, ,, and operation of nonresiden tial buildings. With the broader field covered this year, the Bureau will be able to supply for the first time the answer to the question of how many concerns there are in business, the total volume of business that is done annually, and the total pay rolls and employment by kinds of business. Headquarters for the project is Philadelphia. Fred A. Gosnell, experienced head of former business census, is chief statistician in charge. The field work will be completed within three months after the enumeration starts, and preliminary reports will be available by next July, if not earlier. Only sworn employees of the Bureau of the Census are permitted to examine the individual returns. No access to them is permitted FHA Modernization Booklet THE Federal Housing Administration, Washington, D. C., is distributing its booklet FHA-180, designed to inform public regarding certain provisions of the National Housing Act and the advantages of using government insured modernization credit to improved business property. Under an amendment to Title 1 of the act, the shop, factory, or industrial plant owner, handicapped by worn-out or inefficient equip ment or production equipment, can now bor row funds from the FHA to modernize his plant and equipment. Modernization credit is no longer limited to $2000 for such plants. Under favorable conditions it may be extended in amounts up to a maximum of $50,000. The other new member is James T. Macken zie, metallurgist and chief chemist of the American Cast Iron Pipe Company, who takes the place of R, E. Kennedy, technical secre thetary of the American Foundrymen's Associa tion. Wide advances in the use of alloys were reported by the Foundation as the result of the scientific investigations which are going on in laboratories in many countries. "Interest in these ferrous metals is growing rapidly and use is increasing through spread of knowledge of their properties," said the re port, pointing out that the Foundation's critical survey will go forward in 1936 with the support of American science and industry and of metal experts in many countries. The booklet illustrates numerous examples of modernization, explains the Modernization Engineering Literature - Credit Plan briefly, answers obvious questions regarding the plan, and gives selections from Requested for N ew York the 27 regulations governing banking opera tions under Title 1 of the National Housing State Prisons Act. A list of structures and properties eligi ble for modernization credit loans up to $50,000 is included. Copies of booklet FHA- THE director of education of the' Depart ment of Correction, State of New York, Walter C. Voll, member, A.S.M.E., has asked 180 may be obtained from the Federal Hous for magazines, drawings, courses of study, ing Administration. standards, and other pieces of engineering literature for use in the adult-education project I.S.A. Rules for the Measure being carried out in the prisons of New York State. Readers having material which is Tment o f the Flow o f Fluids suitable for such use are asked to communi cate with Mr. Voll at Clinton Prison, DanHE A.S.M.E. Power Test Code Instru nemora, N. Y., or with the warden, Thomas ments and Apparatus Subcommittee on the H. Murphy. Measurement of Fluid Flow has prepared a few copies of a translation of the third draft, April, 1935, International Standards Associa Texas Tech.ro Hold Second tion Rules for the Measurement of Fluid Flow (by means of the I.S.A. standardized Annual Welding Conference orifice and/or flow nozzle), for loan to those interested. The official trilingual edition of the Rules which the I.S.A. is to issue, will not be available for some time. The subcommittee is especially interested in learning the experiences of those who have used the I.S.A. orifice or flow nozzle. Those interested in obtaining a copy, either to note or for comment, should write to W. A. Carter, 2000 Second Avenue, Detroit, Michigan. TEXAS Technological College at Lubbock Texas, will hold its Second Annual Welding Conference on February 13 and 14, 1936. All persons interested in welding are invited to attend. Mornings will be de voted to lectures and motion pictures on various phases of welding and afternoons to exhibits and demonstrations. Manufacturers of welding equipment will display and demon strate equipment. Inquiries should be direc ted to J. C. Hardgrave at the college. under the law, not even to other Govern mental agencies, and no information will be disclosed which would reveal any of the facts New Appointments to Alloys of Iron Research Committee M. E. Cooley Honored or figures in the returns. PPOINTMENT of three representatives ORTIMER E. COOLEY, past-president A M of the steel industry to the Alloys of and honorary member of The American U.E.T. Elects Officers Iron Research Committee of the EngineeSrociety of Mechanical Engineers, was elected ing Foundation, which is carrying on world an honorary member of the American Society T a meeting of the United Engineering research embracing the entire body of knowl of Civil Engineers at its meeting in Birm A Trustees, Inc., October 24, George L. edge of steel, alloy steel, alloy iron, and cast, ingham, Ala. Knight, member, A.S.M.E., vice-president iwn rought, and pure iron, is announced by the charge of mechanical operations, Brooklyn Director of the Foundation, Dr. Alfred D. Edison Company, was elected president. Other officers elected were Otis E. Hovey, member, A.S.M.E., vice-president; John Arms, member, A.S.M.E/ secretary; and Albert Roberts, assistant treasurer. Representatives of The A m erican Society of Mechanical Engineers on the Board of the United Engineering Trustees, Inc., are D. Robert Tarnall, Walter Rautenstrauch, and Harold V. Coes. Flinn. Dr. John Johnston, director of research of the United States Steel Corporation, was named to the Committee to represent the American Iron and Steel Institute. Wilfred Sykes, a director of the Inland Steel Company, becomes a member-at-large, suc ceeding the late Dr. John A. Mathews, who was vice-president of the Crucible Steel Com pany of America. Medal Awarded C. A. McCune CHARLES A. McCUNE, member, A.S.M.E., director and secretary of the Magnaflux Corporation, was awarded the Samuel Wylie Miller memorial medal of the American Weld ing Society at the fall meeting of that society held on September 30, 1935, for his contribu tions to the promotion of modern welding processes. 138 M echanical Engineering President Batt to Visit Sections and Branches in South VISITS to A.S.M.E. Local Sections and Student Branches in the South will be made by William L. Batt, president of Society, during February and March. His addresses to the Sections will be on "Unity Begins at Home," while he will talk to the students on "The Initiation of the Young Engineer Into His Profession." MR. BATT's ITINERARY February 10, Richmond, Va. February 11, Raleigh, N. C. February 12, Raleigh, N. C. February 13, Charlotte, N. C. February 14, Greenville, S. C., and Clemson College February 17, Savannah, Ga. February 18, Gainesville, Fla. February 21, New Orleans, La., and Tulane University February 24, University of Louisiana February 26, State College of Mississippi February 27, University of Alabama February 28, Birmingham, . Ala., evening meeting March 2, Chattanooga, Tenn., and Atlanta, Ga. March 3, Atlanta, Ga., Local Section meeting with Georgia School of Technology Student Branch March 4, Knoxville, Tenn., and University of Tennessee March 5, Virginia Polytechnic Institute March 6, University of Virginia Air Hygiene Foundation of America, Inc. AIR Hygiene Foundation of America, Inc. has been formed by a large group repre senting various industries, with headquarters at Thackeray Ave. and O'Hara St., Pittsburgh, Pa. The purposes of this organization are to conduct investigations of and to stimulate research on problems in the field of air hygiene and to gather and disseminate factual informa tion relating thereto. It will also cooperate with and assist other agencies active in this field and will collaborate in the coordination of such research efforts. A comprehensive investigation has been begun at Mellon Insti tute of Industrial Research, Pittsburgh, under support of Air Hygiene Foundation of America, in which the hygienic, technologic, and eco nomic aspects of air contamination, especially by dust met with in the industries, will be studied. H. B. Meller, who has been appointed managing director of Air Hygiene Foundation of America, will head this investigation at Mellon Institute. He will be aided by Dr. F. F. Rupert. Other assistants will be added to the staff of the Foundation as the work progresses. The investigational program will also em brace medical considerations and studies. The medical adviser will be Dr. Samuel R. Haythorn, professor of preventive medicine in the School of Medicine of the University of Pittsburgh and director of the Singer Research Laboratories, N. S., Pittsburgh. A.S.M.E., Semi-Annual Meet Use of the A.S.M .E. Pin ing at Dallas, Tex., June 15-20 PON recommendation to the Council of the A.S.M.E. at the Annual Meeting U HE program for the Semi-Annual Meeting in December, 1935, by the Special Committee Tthe to be held at Dallas from June 15 to 20 is on the Use of Society Pin, the following now being developed. E. W. Burbank, chairrecommendations were voted: That the use man of the North Texas Section, is organizing of the present standard form of badge, i.e., the local arrangements. The technical pro the blue enamel, should be restricted to gram will have sessions on Petroleum, Process Fellows, Members, and Associate-Members; Industries, Machine Shop, Power and Fuels, (2) that for Associates the standard size Hydraulic, Management, and Fluid Control. badge should be permitted but the enamel Papers that are to be preprinted in Transac should be a dark green; (3) that the Junior tions in advance of the meeting must be sub and Student designs should be continued as at mitted for consideration by March 15. present. A Member's Responsibility in Indorsing a Candidate for Admission to the A.S.M.E. THE Standing Committee on Admissions comment is made. The reference simply (formerly Membership Committee) has checks a definite grade. In such cases, if the built up a procedure or tradition regardingapplicant fails to have a majority of positive standards for admission to membership in endorsements and the professional record is which the changes are few, constituting an not thoroughly convincing, recommendation evolution in the stiffening of requirements to Council is witheld until further investiga rather than radical changes of policy. tion is completed to the Committees' satis Because the committee welcomes all real faction. assistance that it can secure from the member ship at large, individually or by Sections, it CONSTITUTIONAL REQUIREMENTS NOT wishes to set forth some of its operating UNDERSTOOD methods. A great difficulty which can only be appre INFORMATION SENT TO REFERENCES ciated by those of us who have served and have become thoroughly imbued with the When an application is received, the per traditions of the Admissions Committee is tinent information contained therein is sent that so few members, even in the case of some to the references furnished by the applicant. of our most prominent ones, fully realize the It might be assumed that these references are requirements. Because an applicant is active individuals prejudiced favorably to the can in his section, of pleasing personality and high didate, but it has been found that this is by character, constitutional requirements of the no means the case. In other words, members simplest kind are overlooked. For instance, have a high regard for the Society and fre every now and then word is received from a quently, intentionally or otherwise, give the local section when a case is referred to it, committee information which is not favorable. that the candidate should be admitted to the The reference forms, when returned, arc dis grade he asks for "because he has higher tributed in books, one to each member of the qualifications than many of the existing mem committee, about a week before its monthly bers." That kind of a reply has absolutely no meeting, and each member makes his own weight with the Admissions Committee and notations and records his own opinion. At results in a poor opinion of the person making the meeting, a preliminary vote is taken, after such a reply. No doubt there are men in which, discussion generally takes place before the Society who are not of membership caliber a final vote, is taken. Not infrequently, the in spite of the care taken, but that is no excuse committee regards the information supplied for increasing the number of such members. by the candidate as insufficient and the appli There have been cases where a statement such cant is asked for additional information or as the following is made: "This applicant is elaboration, or is asked specific questions an exceptionally able engineer and should be regarding his record. Frequently all the given the grade of Member, although he is references do not reply or replies arc of an several years below the age limit required by unsatisfactory character either in kind or the Constitution. I recommend that the detrimental to the candidate. Committee waive this Constitutional require Frequently, all five or more references check ment in this case." Needless to say, the for the definite grade of Member, or other Committee can pay no attention to such a grades as the case may be, but comments are recommendation, frequently made by promi such that the Committee does not believe the nent members who ought to know better. reference understands the constitutional re quirements, or for one reason or another the APPLICATIONS PUBLISHED affirmative vote is not satisfactory to the All applications for membership are pub Committee. In spite of the request contained lished by the Society in ample time for any one in the form to the reference for reasons a interested to look them over and send a con member should receive a certain grade, often fidential communication to the Committee, no reason is given. The sheet is merely en but such comments are rarely received. Mem dorsed "Yes" and many times not even that bers apparently are either not willing to take 140 M echanical Engineering the trouble or do not care to become involved in a matter of this kind. The Committee believes that it is the duty of every member to take such action, and while he need not recommend one way or another, he should give facts which he believes should be con sidered by the Committee. The Engineers' Council for Professional Development which includes a committee from The American' Society of Mechanical Engineers and which has the cooperation of the four Founder Societies, the Society for the Promotion of Engineering Education, the American Institute of Chemical Engineers, and the National Council of State Boards of Engineering Examiners, which is interested in state licensing, has given much considera tion and is continuing to do so, in regard to the uniformity of requirements for engineering degrees, standard grades of membership, and standard forms for requirements by state licensing boards and by the engineering societies, all looking to professional recog nition on a uniform basis. In due course, it is anticipated that individual examinations may be undertaken which will have such universal approval that qualifications may be more easily and accurately determined, but until such standards are set up and mutually agreed upon, the Committee on Admissions feels that its present procedure is adequate and may be counted upon to maintain a high standard, if the membership at large charge themselves with a share of the responsibility. Henry A. Lardner, Chairman Committee on Admissions Meeting Places of Local Engineering Groups IT HAS been suggested that for the benefit of those members who travel regularly, or even occasionally, there be published a list of the meeting places of local engineering groups, with especial mention of those groups who hold weekly luncheons. Atlanta: Atlanta Athletic Club, 166 Car negie Way, Mondays at 12:30 p.m. Baltimore: Engineers' Club, 6 W. Fayette St., daily except Sundays from 12:00 to 2:00 p.m. Boston: Engineers' Club, 2 Commonwealth Ave., third Thursday of each month at 6:30 p.m. Buffalo: King Arthur Restaurant, Dela ware Ave., second Tuesday of each month at 6:30 p.m. Chicago: Chicago Engineers' Club, 314 Federal St., Tuesday at 12:15 p.m. Charlotte: Efirds' Department Store, every other Monday at 1:00 p.m. Cincinnati: Engineers' Club Rooms, Ninth and Race Sts.', at 8:15 p.m., fourth Thursday of each month. Cleveland: Hotel Statler, Cafeteria, Euclid Ave., Wednesdays at 12:30 p.m. Colorado: Chamber of Commerce, Sixth floor, 1726 Champa St., Denver, fourth Friday of each month at 6:30 p.m. Columbus: Engineers' Club, Chittenden Ho tel, Spring and High Sts., 12:00 noon, third Friday of each month. Inland Empire: Davenport Hotel, Spokane, Wash., Wednesdays at noon. Indianapolis: Rose Polytechnic Institute, Terre Haute, Ind., luncheon daily. Knoxville: Knoxville Technical Club every Monday at 12:30 p.m. at the Andrew Johnson Hotel. Los Angeles: Engineers' Club, Biltmore Hotel, 515 South Olive St., Los Angeles, Calif. Thursdays at noon. Milwaukee: Wisconsin Club, 900 W. Wis consin Ave., third Wednesday at 8:00 p.m. Ontario: Faculty Union Room, Hart House, University of Toronto, second Thursday of each month at 6:15 p.m. Philadelphia: Engineers' Club, 1317 Spruce St., fourth Tuesday of each month at 6:00 p.m. Providence: Providence Engineering Society Building, 195 Angell St., first Tuesday of each month at 8:00 p.m. Rochester: Sagamore Hotel, 111 East Ave., Tuesday at 12:15 p.m. St. Louis: Washington Univ. Campus, Lindell & Skinner Boulevards, fourth Friday of each month at 8:15 p.m. San Francisco: Engineers' Club of San Francisco, 206 Sansome St., Thursdays at noon. Western Massachusetts: Hotel Highland, Hillman St., Springfield, Mass., third Tuesday of each month at 6:30 p.m. Western Washington: Engineers' Club, Arctic Building, Seattle, Wash., luncheon daily at noon. Worcester: Worcester Polytechnic Institute, Worcester, Mass. Time varies. Youngstown: Republic Rubber Club House, Albert Street, fourth Monday of each month. Coming Meetings of A.S.M.E. Local Sections H ille, Edward, Forest Hills, L. I., N. Y. Kranich, Henry O., Toledo, Ohio Krause, Robt., Chicago, 111. Laird, I. Lavren, Walpole, Mass. Lawrence, J as. V., Long Island City, N. Y. Lerch, Werner E., Long Island City, N. Y. Marx, Erich, New York, N. Y. N agoshiner, Geo.', New York, N. Y. N icolai, A. Lewis, New York, N. Y. Oliker, H erman, Brooklyn, N. Y. Rabe, J. S., Philadelphia, Pa. Schoenfbld, Ed., J r., Montrose, N. Y. Singh, K ishan, Jamshedpur, India Strauss, J erome, Bridgeville, Pa. (Rt & T) Torok, Elmer, Elizabethton, Tenn. (Rt) Van Dykb, J os. J., Jackson Heights, L. I. N. Y. Waddell, C. L., Morristown, N. J. Warner, Leslie T., Concord, N. S. W., Australia Williams, Arthur, Hammond,. Ind. Z ahel, Alex., Yorktown Heights, N. Y. Change of G rading Transfers from Junior E ngle, Daniel E ., Akron, Ohio H oagland, Cecil N ., Bridgeport, Conn. N icastro, G eo. j . , Woodcliff, N . J. Necrology THE following deaths of members have recently been reported to the Office of the Society: Connor, H erbert R., May, 1935 H owe, Ralph W., October 23, 1935 Land, Frank, December 24, 1935 Lewis, David J., Jr ., December 26, 1935 Rossmassler, Carl, December 28, 1935 T urner, Robert T., November 13, 1935 Youngstown: February 24. Republic Club House, Albert St., Youngstown, Ohio. A speaker from the Republic Steel Corporation will provide moving pictures and sound recording, showing the manufacture and application of stainless steel. A.S.M.E. Transactions for January, 1936 THE January, 1936, issue of the Trans actions of the A.S.M.E., contains the following papers: Engineering Problems in Aircraft Operation Candidates for Membership in the A.S.M .E. in High Altitudes (AER-58-1), by R. E. Johnson and R. F. Gagg The Flow Characteristics of Variable-Speed THE application of each of the candidates Reaction Steam Turbines (FSP-58-1), by Adolf Egli listed below is to be voted on after Febru Distribution of Air to Underfeed Stokers ary 25, 1936, provided no objection thereto is made before that date, and provided satis (FSP-58-2), by A. S. Griswold and H. E. factory replies have been received from the Macomber required number of references. Any member Film-Lubrication Theory and Engine-Bearing having comments or objections should write LoDcoesmigontiv(Oe GaPn-5d8-1C)a,rbyJoEu.rSn.alDenLnuibsroincation to the secretary of the A.S.M.E. at once. (RR-58-1), by E. S. Pearce ; N ew Applications Bealing, E rnest, York, England Bergner, H. W., Chicago, 111. Brinkman, Chas. F., Newark, N. J. (Rt) Cronin, A rthur D., Detroit, Mich. A Study of the Turning of Steel Employing a New-Type Three-Component Dynamometer (RP-58-1), by O. W. Boston and C. E. Kraus DISCUSSION Cross, B. J., New York, N. Y. On previously published papers .by S. D. Erwin, Robt. M., La Habra, Calif. Mitereff; O. R. Wikander; and F. F- Gaddis, H. L., Dallas, Tex. Fisher and E. T, Cope. G iangrandb, Vincent J., New York, N. Y. For closing dates on discussion, see footnote H iggins, Alexander, Calgary, Alberta, Can. on first page of each paper.