Document 2EMajMgLwnD05nKnzqEEeL9p

The American Ceramic Society PLAINTIFFS EXHIBIT February 15,1993 I hereby certify that the attached copies of Ceramic Abstracts, Volume 19,1940, are true and accurate copies, which are maintained in the normal course of business at the American Ceramic Society, 735 Ceramic Place, Westerville, Ohio 43081. I cannot verify the accuracy of copies from Iron & Coal Trades Review, Volume 139,1932. Christine Schnitzer Product Manager Ceramic Information Center a 735 Ceramic Place Westerville, Ohio 43081-8720 614-890-4700 TWX: 7101109409 A fl '' 18 (4V (S) CERAMIC ABSTRACTS Compiled by The American Ceramic Society Volume 19, 1940 Ross G. Puxdv, Editor i Maxy J. Gas CEmily Van Scho ice Dobothy J. Wallace 1 Assistants Committee on Publications: J. D. St-T-LIVAN. Chairman, E. E. Uauaxes, J. B. Ai*stxn\ A. N. Ferae. R. C Pvrdy ABSTRACTERS J. S. Austin L. M. Church A. A. Ayers XV. M. Cohn L. R. Barrett M. V. Ceodoide K. W. \\\ Bartlett P. S. Dear : A. C. Bevao Frank Fisher : D. A. Biddle XV. O. Foster A. Biddulpb J. L. Callup V. 1.. Bo*aa J. O. Cat XV. II. Bruckner K. A. Gregory P. 1' Uudoikov Robert Halle j. C. Chastoo Max Hartrohctra l J. Haiti F. C. Heck R. A. Hciodt P. C. Herald M. B. HiU C. M. Hutt I. F. Hyde Herbert Insley C. B. lenni B. 2. tCamicb B. E. Kialtulkin XI*. O. JCucaas J. G Phillips C. R. ShcJtoa Seiji Koodo E. C. Pierce H. E. Siopsoa Veiio Kora Alexis Piaeus A. P. Son Robert Kama M. E. Poor P. E Soaaesscheio B. B. Last Katberioe Reed A. G. Stem XV. Lotweotbal H. K. Ricbardsoo B. H. Stroa F. S Mallttie R. A. Roooebeck M. Takei V. 5. dr Marchi B. C. Ruprecbt L. E. Tbiess I. F. Mar A. B. Searlc Haas Thuroauer E. H. McClelland J. P. Shaonk J. M. Noy Ludlle Shattuck E. I. Vaehusica F. J. Zvaaut Editorial Ofice: 2525 North High Street, Columbus. Ohio ' Publication Ofice: 20th and Northampton Streets, Easton. Pa. r V r91 r-.. V 'V K * ... kr.:* i <+ IV V r i- * M. + I r l b u tc `.I I: : 1940 General T9 General Ceramic Uboratoriei: Georgia School of Technology Anon. Ceram. Ate. 34 U! 1- (1939). Massachusetts Inatitute of Technology. Ibid.. (2| 44. New York State College of Ceramic*. Ibid., p. 45. Rutger* University. /4td,, (31 78. University of Illinois. Ibid.. [1| 13.--The { laboratories are briefly described and illustrated. F.G.H. Ceramic schools. Current survey of status and prog* I res*. Anon. Ceram. At*. 33 [6] 171-91 (1939).--A comprehensive survey of ceramic schools throughout the country is given. The course of instruction, the teaching staff, the research staff, and the student body of each of the following schools are described: Georgia School of Technology, University of Illinois, Massachusetts Insti- * tute of Technology. Missouri School of Mines, New York State College of Ceramics, North Carolina State College. University of North Dakota, Ohio State University. Pennsylvania State College. Rutgers University. Virginia Polytechnic Institute. University of Washington. Univer sity of Oklahoma. West Virginia University, and Carnegie Institute of Technology. Illustrated. F.GJi. Contract law for engineers. L. T. Pauk. Combat- lion, 11 [21 33-34 (1939).--P. explains implied and ex pressed contracts, as interpreted by the higher courts, with particular reference to the employment of engineers and personal services rendered by them. The liability of employers in such cases is illustrated by a number of court decisions, some of which are cited. H.E.S. Control of speed is important factor in cement manu facture. Anon. Concrete, Cement Mill Ed.. 47, 233-39 (1939).--Early devices were friction driven. Later, vari[ able-rpeed motors were used. Now a vari-pitch speed changer is used which is operated by a small pilot motor and which is either automatically or remotely controlled. New power self-synchronizing drives may be used to keep a kiln and the kiln feeder in synchronism. W.D.F. Development of central-heating systems. Lxugi Ranzl Cecundh.-Ini., 60 [501 753 (1937).--R. describes the de- . velopment of modem central-heating systems. A new type of installation is explained, and various examples are calculated. W.DJC. - Effect of condensate extraction on efficiency of the heat cycle. W- M- Meijer. Combustion. 11 [21 30-32 (1939).-- M. contends that the value of high superheat as a means of improving the efficiency of steam power plants is being overestimated and recommends the use of high initial steam pressures at moderate initial superheat combined with the mechanical extraction of condensate at appropriate stages of the expansion. H.E.S. J Fatalities from silicosis and asbestos!*; their incidence in industry. Anon. Iron a* Coal Trades Her., 139 [3732] 336 (1939).--The annual report of the Chief Inspector of Factories shows that from 1935 to 1933 inclusive, deaths from the two lung diseases in the refractories industries and in the manufacture of pottery have been approximately constant, Le.. GS in 1935, 56 in 1936. 83 in 1937, and 60 in 1938. Sandstone quarrying and dressing took 40 lives in 1935. 43 in 1936.19 in 1937, and 27 in 1938. Preventive measures have aided in a generally small decrease: some of these measures are as follows: (1) use of alumina for flint in china bedding. (2) use of alumina for siliceous ma terial in parting powders. (3) use of nonsiliceous abrasives for sand or flint in blasting, (4) use of nonsiliceous material for kieselguhr in the slow cooling of steel, and (5) use of nonsiliceous material for silica brick for lining steel and other furnaces. See `China--." Ceram. Abs., 18 !2) 54 (1939). M.H. Gas heating installation. H. Dietrich. Gesundk.-Int.. 60 [45] G.. 11937).--D. surveys the developments of gas healing after the World War and discusses the gas single heating system, the gas central-heating system, special gas tanks, tanks with built-in burners, rentability and gas prices, and the experimental capacity of a boiler on a low pressure steam-beating system and on a warm water heat ing system. Results of conducted experiments arc stated. W.D.K. Handling and disposing of recovered fly ash and dust. J. T. Dsvtsch. Combustion, 11 [5] 22-24 (1939).--Three methods are reviewed, including the vacuum, the sump, and the introduction of the dust by means of a water- cooled ram into a slagging-bottom furnace near the level of the molten slag. The last method is discussed in detail. 1LE.S. Health damage by means of industrial dust. Otto Schultz. Gasmaske, 11, 57-6G (1939).--Pure coal dust is not dangerous; neither is silicon carbide nor corundum dust. Tin, copper, bronze, and aluminum dust make slight alterations in the lungs, and iron oxide makes stronger alterations, but none of these dusts affects the health. Of the dangerous dusts, free silica usually causes silicosis, which is the most widespread and dangerous disease, after only a 5- to 10-year exposure. Asbestos dun causes asbestosis by mechanical irritation. Lung cancer is caused by radioactive dust. The symptoms are like those of sili cosis. Chromate dust or mist causes nasal sores and also cancer. It has a long latent period, up to 24 years. Thomas slag causes a severe lung inflammation, as it reduces the resistance of the body to bacteria. This can occur im mediately after exposure and has a high fatality. Pyro- lusite causes a different lung inflammation. Glass wool acts in a similar manner to asbestos. Over sensitiveness to flour, grain, hair, etc., causes asthma. Certain fungi can grow in the lungs. Methods of prevention are dis cussed generally. W.DJ. Healthy air, a guide for plant superintendents and workmen. Otto Elsner. Cesundh.-Int.. 60 [44] 676 (1937).--A review issued by the German Society tor Labor Protection gives the various kinds of air contamination and testing. Natural and artificial air-conditioning methods are discussed from the viewpoint of health, and a special chapter describes the airing of workshops, offices, etc. W.DJC. How benzol poisoning may be avoided. Anon. Gesundh.- In[.. 60 [521 795 (1937).--Forming benzol vapors must im mediately be caught by suction. A good supply of fresh air is necessary during the cold season, and the air should be replenished with prewanned air. Benzol vapors are heavier than air and. for this reason, sink to the floor. When installing a new air-ventilating system.- therefore, suction openings should be located in the floor or near it. Pieces treated with a benzol-containing solution should be dried in a well ventilating drier cupboard or special drying rooms. Benzol-containing vessels must be kept covered. W.D.K. Improved system in the application of noncondenaing or extraction turbines. H. W. Caoss and E. S. Wells. Ja. Combustion. 11 (1 ] 32-35 (1939).--Since electrical output is definitely established by the energy drop between initial and exhaust conditions and by the quantity of steam flow, increasing the total steam pressure at the throttle for a given pressure increases the available energy and conse quently the electrical output.' The application of'a com bined desuperheater and feed-water heater at the ex haust is advantageous in realizing gains from the tlse of higher temperature steam. Examples demonstrating the possibilities inherent in such systems are illustrated and explained. H.E.S. Lighting for special industrial purposes. W. R. Stevens. Trans. Ilium. En*. Soc. [London], 3 [1] 3-16 (1938).--S. describes installations requiring special lamp fittings for explosive and moisture-ridden atmospheres and the use of special sources of light, such as carbon dioxide discharge, daylight tubes, special daylight tungsten fila ments. and high-voltage fluorescent tubes, for color match ing surfaces and special inspections. H.K.R. Living and working conditions in the tristate mining districL Evan Just. Mining Congr. Jour.. 25 [11] 44--43 (1939).--Dust in the mines is kept within safe limits by wetting down, spraying, and ventilation. Above ground, dust from "chat piles" is practically nonexistent as they arc coarse material. On windy days dust is blown from a few flat accumulations of sand. Road dust, however, ac- I 1040 General SI I tests water, hardness has been developed by the German and the size and shape of the body. There is an optimum Society for 'Chemical Apparatus. W. D.JC. temperature at which drying is most readily carried out: Surface heat losses from outside furnace walla. J. G. the smooth nature of the relationships between greatest Coutant. Heat Treating St Forging, 23 [9| 463 (1939).-- safe rate of drying and the dimensions of the test pieces Aluminum i paint reduces heat loss from furnace walls. suggests that an ultimate understanding of the phenome See Ceram. Abs.. 19 [1] 16 (1940). S.S. non of cracking will be achieved. A theory of the mechanism of the flow of water through BOOKS AND SEPARATE PUBLICATIONS plastic day during drying has been developed, in which the A.S.T.M. Standards, 1939. American Society for force causing the flow is regarded as a repulsion between Testing Materials. Philadelphia. Pa. Price to non- the day partides which are separated in all directions by members SS.00 one part. S13.00 two parts; 323.00 three water films. A measure of this repulsion is obtained from parts.--The book is in three parts: 1, Metals: Ferrous and the moisture contents assumed by the clay when various nonfetTOus metals are discussed; methods of chemical pressures are applied through porous pistons into which analysis are not riven. General testint methods are pre the water is allowed to escape. This pressure is an ex sented. Q, Noometallic material*--constructional. This ponential function of the moisture content as is also the part includes cementitious materials, concrete and aggre- "aqueous conductivity" or the rate of flow of water through fates. masonry buildinr units, ceramics, refractories, pvro unit volume of the day under unit pressure. On this basis and tile, thermal insulating materials, timber preserva the distribution of moisture content at any time through tives. paints, varnishes, and lacquers, road materials, out a drying shape can be theoretically calculated, the waterproofing and roofing materials, and soils. General analysis being analogous to that of heat diffusion. A testing methods and thermometers are described. QX, Non- strict solution is not possible, but experiments on a num metallic materials--general. Fuels, petroleum products, ber of days show a means of approximation which permits electrical insulating materials, rubber textiles, soaps and the calculation of moisture-content distribution in bars detergents^ paper, plastics, and water are covered. Gen drying from one end only. The experimental verification eral testing methods are given. Available from Amer. of the theoretical results confirms the hypothesis. Soc. Testing Materials. 260 S. Broad St.. Philadelphia, Pa. Many years' study of electrical insulation and the ma ! F.F. terials used therefor has greatly improved the reliability Finding [List for United States Patent, Design, Trade and the advantageous selection, preparation, and use of Mark, Reissue, Label, Print, and Plant Patent Numbers. insulating materials. Better insulators have been de- M. Randall and E. B. Watson. University of Cali veloped, thus reducing the size and eventually the cost of fornia Press. Berkeley, 1938. 31 pp. Price 35c. Reviewed electrical apparatus of all kinds without loss of quality. in AfecA. Eng.. 61 [5J 402 (1939). F.G.H. The suitability of certain glasses for use in the manufac Report of the Department of Scientific and Industrial ture of tdephone insulators is shown. The degree of l Research, 1937-1938. H. M. Stationery Office, London. homogeneity in optical glass is almost completely de Price 3s. Reviewed in Pottery St Class Retard, 21(4) 89-90 termined by the temperature conditions prevailing during (1939).--Methods have been developed for assessing the annealing process. An investigation has been made of weathering characteristics of clay products fired under the maximum temperature gradients in an annealing oven various conditions. Work on clay roofing tile has been consonant with the production of substantially homogene continued.! Investigations on refractory materials include ous optical glass. The cooling schedules of the annealing (1) the pressing process and its. relation to the texture of process were experimented with to determine the minimum clay, silica, and sillimanite brick; (2) the drying of period of annealing for glass of high optical quality. clayware; and (3) the firing operation. A careful study of Methods of producing light etch marks on glass have the smoke' emission from various intermittent kilns firing been developed, and an optical system to enable the degree blue and brindled heavy clay products has been made, of polish of a glass surface to be assessed has been devised. and suggestions are advanced for its reduction and con The preparation of filing materials for etched lines, required trol. Laboratory work aiming at relating the conditions to be unaffected under specified conditions, is described. of atmosphere and temperature with the color of blue A.B.S. firing clay's has also been undertaken and has progressed Silicosis and Asbestosis. Edited by A. J. Lanza. y satisfactorily. Oxford University Press. New York. 1938. 439 pp. Drying ;cracks are due to differences in moisture con Price 34.25. Reviewed in Meek. Eng., 61 [51 405 (1939).-- tent established in different parts of the clay body, espe The medical and public-health aspects of these industrial cially between the surface and the interior. Differential dust diseases are comprehensively presented in this book, shrinkage thus occurs as drying proceeds, and stresses are to which several physicians have contributed. The history produced.! The direct method of studying the problem of the diseases, their symptoms and diagnosis, their consists in determining the fastest rate at which particular pathology, and their prevalence in various occupations are shapes of [a given clay can be dried with safety, and the discussed, as well as methods of prevention and control. variation of that rate with such factors as the temperature Each section has a bibliography. F.G.H. # I I So. 6 4icr^ alyses i from 1 with i indiic raw . Many i lines tap of is in* i-D. irrical R- G. W. E. 3433. . and tectrov-H. 3cress U.S. ree.-- tanga- ite ore .te ore white U tail s' ares V.H. WALD. 9.--la ate of ate to up to at k is h acid, larger which above, limes* save a me of tint) is an in- as and r rates :han is ic jive B.S. , 1940 Chemistry and Physics--General 149 composition and properties of the solid and liquid phases, and the fas phase. P-B. St E.S. Prevention and treatment of lead poisoning. Imre Heller. Orrosi Hetiiap, 83, 639-41 (1939); Chem. Abs., 33, S329 (1939).--In Huncarian Pb works. Pb poisonins occurs in lOt) to 200 of 1'J.OUO laborers annually. Lead ac cumulated within the human organism can be mobilized bv modifying the Ca/P balance cautiously. This was done in clinical experiments by a diet poor in Ca and S to 10 gm. Xa phosphate given each second day for 3 to 4 weeks. Any secondary effects of phosphate can be balanced by the administration of thiosulfate from time to time. Silicic add gels: CL Charles B. Hurd and Harris W. Pato.x. Jour. Pkys. Chem.. 44, 57-02 (19411).--The effect of a change of pH on the time of set of gels produced bv mixing solutions of sodium silicate and acetic acid is discussed. For Part V see Ceram. Abs., IS |3| 103 (1930). R-A.G. Theory of light scattering. S. Parthasarathy. Phil. Slat- 29 (193J 148-53 (194U).--P. shows that the scatter ing of light observed by Krishnan in binary liquid mixtures ("Molecular. . Ceram. Abs., 17 [3] 119 (1933)) is purely molecular, while no scattering arises from clusters, if any, at the critical solution temperature. No new theories as, e.`g.. those of Frenkel. Cans, or Muller, appear to be neces sary to explain Krishnan's results. R.H. BOOK Science Front, 1939. F. Sherwood Taylor. Cassell & Co., Ltd., London. Price 7s. 6d. Reviewed in Times Lit. Sttpp.. 39 [1984] 79 (1940).--T. describes recent developments in science, including theoretical researches and technical inventions. Illustrated. K.W.W.B. PATEXTS Cadmium-red manufacture. Walter F. Muster (Interchemical Corp.). Can. 387,430, March 12. 1940 (June IS. 1937; in U. S. July 9. 1938). G.M.H. Enamels and glazes and method of producing. Carl OberUvnder and F. H. ZsatACXE (Sioto G.m.b.H.). U. S. 2,194.246. March 19. 1940 (May 20, 1936).--A preparation for improving enamels, glazes, etc., comprises a magnesium borosilicate having substantially the follow ing composition: silicic acid 30 to 50. boric acid 10 to 30. magnesium oxide 15 to 35. and alkali compounds 10 to 297c. Magnesium titanates and method of making. J. A. Plunkett and Eugene Waxxer (Titanium Alloy Mfg. Co.). U. S. 2.196,325, April 9. 1940 (March. 5, 1933). --A calcined synthetic magnesia-titania composition con taining chiefly finely divided magnesium litanaie chemi cally combined with 3 to 12% of silica and alumina, the ratio of silica to alumina ranging from 3:1 to 12:1. of particle size substantially all within the range of 0.5 to 2 microns, and having a refractive index of about 2.15. Production of beryllium compounds. Carlo Aoamou ( Perosa Corp.). C. S. 2.190.048. April 2. 1940 (March 20. 1937;.--A process for the production of beryllium oxide from minerals containing beryllium and for the cyclic re covery of the reacting agent employed consists ia powder ing the beryllium-bearing ore.'mixing the powder with an alkali bifluoride in an amount corresponding to 2 roots, of bifiuoride for every BcO molecule present in the ore. add ing water to form a paste, compressing the paste to briquettes, healing the briquettes to a temperature be tween 550* and 800*C. to cause the fluorine to combine with the beryllium to form a double alkali fluoride, leach ing the reaction product with pure water at a temperature of about 90* to 100 *C., adding alkali hydroxide to the alkali beryllium solution to precipitate beryllium as beryllium hydrate and form neutral alkali fluoride, sepa rating the neutral alkali fluoride, calcining the beryllium hydrate to beryllium oxide, and treating the neutral alkali fluoride with a strong acid other than hydrofluoric to con vert the neutral alkali fluoride to the corresponding acid fluoride. Pure titanium dioxide. W. W. Plechnex and A. W. Hixson (National Lead Co.). Can. 386.985. Feb. 20.1940 (Oct. 12. 1937). G.M.H. Pure titanium oxide. W. W. Plechner and A. W. Hixson (National Lead Co.). Can. 386,625, Jan. 30. 1940 (March 7.1938). G.M.H. Titanium pigment manufacture. Robert W. Ancrum and Assux G. Opfegaard (National Lead Co.). Can. 386.623. Jan. 30. 1940 (Nov. 29. 1937). G.M.H. Zirconium oxide aud method of making. C. J. Kinzie. and D. S. Hake (Titanium Alloy Mfg. Co.). (J. S. 2.194,- 426, March 19, 1940 (July 23. 193<).--A crystalline zir conium oxide obtained by the calcination of a zirconium- oxygen-carbon compound without substantial grinding of the calcined product characterized as an essentially white powder and as being essentially white in color and consist ing of crystal particles having their length greater than their width and tbeir thickness less than their width, an index of refraction of about 2.3 to 2.4. and an adsorbed colorless carbon content of about a stoichiometric equiva lent of 1.64% carbon dioxide. ised in teral is V.C. values. 44, floccu(tannic .ioxide. ydroxA.G. EMING. 1939). se rule 5.H. Ko. 7. -sed on >uld be fleet of tstidty ount of q. cm. heterorature. General Absorption of lead and arsenic through akin. Anon. Jour. Amer. Med. Assn., Queries dr Minor Jfotes, 114, 604 (Feb. 17.1940).--Lead and arsenic absorption through the skin does not occur to an appreciable extent in contact with aqueous solutions of these compounds in concentrations be low 0.5 mgm. per 100 cc. of solution. It is unlikely that sig nificant quantities could be ingested because of contami nated hands. F.S.M. J Clinical studies in asbestosis. M. J. Sross. Amrr. Per. Tubtre- 41, 12-21 (Jan.. 1940).--This report is based upon examination at ISO persons formerly employed in the opening, carding, spinning, and weaving departments of an asbestos brake lining plant. F.S.M. Compensation for industrial injuries aud occupational diseases. E. R. Koonti. Jour. Amer. Med. Assh., 114. $oo-69 (Feb. 17, 1940).--K. gives an excellent discussion of a few at the many legal and medicolegal phases of com pensation laws of prime importance to physicians interested in the field of industrial medicine. Tables show the com pensability of occupational diseases, limitations of time and cost of medical and hospital benefits in compensable injuries and diseases, and the determination of medical matters under compensation laws: all data are given by states. F.S.M. Consider the audience. S. Marion Tucker. ASTM Butt., So. 103. pp. 27-29 (March. 1940).--T. stresses the importance of presenting papers effectively. The causes of complaints are considered. The preparation of a technical paper is taken up with regard to the content and style. The manner of presentation is also considered. The audience must be considered first in technical paper presentation. F.F. Dust-control syttems for the metal-finishing industry. Richard T. Pace. Metal Cleaning dr Finishint, 10 ;3i 53(1--47 (1938).--Dust is undesirable in any industry. Many of the metal-finishing processes, e.g., sandblasting, grinding, buffing, polishing, etc., are outstanding dust producers. Control procedures discussed are (1) personal respiratory protection. (2) substitution of a less harmful material causing the dust. (3) wet methods. (4) complete enclosure of the dusty process, (5) segregation of part of the equipment, (6) improved ventilation. (7) partial en closure under negative pressure, and (8) local exhaust ventilation. A detailed study of dust-collection systems is presented. Air motion is discussed, and a table of air speeds in ducts necessary to convey various materials is given. A table shows the minimum thickness of metal for straight exhaust piping. Fans and cleaning apparatus * 8 I 1..9.40 General 205 joa! I investigations are of considerable importance and fre- S. I aucntJy accompany the chemical work. The department I is equipped for complete mineralogical examinations by t*R. I microscopic and other processes used in determining rocks. -1 minerals, ores, and concentrates of all types. It is fre- lt. I fluently possible from the results obtained to offer opinions 137. I ,,pon the commercial value of a mineral product or to give :ali* I gdvice on methods of preparation for the market. Chemi- car- I enj and mechanical analyses can also be made of soils. I I. I K.R. Fatal subacute occupational lead poisoning. Werner | I I I I tins II :or- I 122 I EKSRAaor. Arch. Getrerbepath. of Getrerbehyg., 9, 407-13 iftcj**).----Industrial lead poisoning as a rule is a chronic poisoning. Characteristic symptoms appearing suddenly. like the colic and intestinal stoppage, show that the poison has been at work in the system for a long time, Acute poisoning as an industrial disease is seldom encountered. E. reports an acute case which came to the Berlin Clinic for Industrial Diseases and discusses its manifestations. On Dec. 4. 193S. a sprayer of lead. 49 im* | years old. was brought to the clinic in a dangerously ill rho I condition. Very carefully and fully he was examined; lay I the next day he died. For several weeks as an occasional nal I worker he had been spraying cable muffles in a cable tea. in II plant. The workspace was 3 x 4 x 3m.; the spraying was expected to be done under a hood. The worker used a ip. ] spray pistol in which a lead wire was inserted and the a" I me ual I I I on I 22 I propane gas flame mixed with air. which was introduced into the pistol at the same time, melted the lead wire, The molten lead was at once ejected by the pressure of the air. spraying the muffles revolving in front of it. During this process the worker was expected to wear a mask and to manipulate the pistol through slits. About the middle ry. I of November he had been seized with violent pain and. nd | vomiting; he was off from work for 8 days and resumed ms .he I I work again late in November. The hood apparatus was then out of repair; three other men working in his absence ;h. | in the same small space, with very low suction in the id* I ventilating apparatus, caused the returned worker to ask ta* I for the night shift where he could be alone. On November ni* I 30 he was overcome with the same violent symptoms as ex. I before. Being somewhat better by the next night, he :ot I insisted on working, only to return home in the same con* .n- I dition. with additional symptoms: his wife noted that he I his face was as black as lead. E. details the man's further ed | breakdown and the efforts of the company physician in to I palliation; these failing, the victim was transferred on sg I Dec. 4 to the Occupational Clinic. The plant conditions nt | under which the lead spraying took place were examined I and reported on by E. after the autopsy. A large hole i*. I tras found in the left side of the framework supporting 2 I the hood through which the sprayed lead had been escap* $7 I ing into the small enclosure: lead dust lay heavy on the *ts I glass valves of appliances carrying the cables; the clothing be I and shoes worn by the various shifts were loaded and ag I * sodden with the scattering lead dust: the mask of the of | worker was in disrepair, so that he might not have worn it id I on his final night shifts. He must have breathed the lead ah I dust in its most finely divided particles, i.e., in almost e- I molecular form. Such an aerocolloid condition is taken ic I up by the organism with special ease and constitutes the r- I highest possible risk to the subject. The lungs in this case r* I were permeated with it. and the blood readily carried d- I this fatal dust to the entire system. From the evidence tg | derived from the illness, the autopsy, and the plant. E. rondudes that the poisoning could be called acute but also subacute, the worker evidently having been sensitized by his first attack and the subsequent exposures, massive in character, sustained December 1 and 2. An inspector testified that, after being placed on the night shift, this worker had done the work of three ordinary men on the spraying Hcncc his constitutional resistance was utterly hroken down beyond repair. The lead content of the urine was 2140 y in 10 pm. of dry feces, 490 y in 10 gm. of the liver, and 370 y in 10 gm. of the kidneys. K.R. Fuel gas, generator. Harry A. Ciurts. Ralph B. Stitzer. axo Wilder J. Dariiy. Ind. Eng. Client.. 32 (81/37-62 (1940).--Developments in the use of electrical energy as a source of heat lor the carbonization of coal are described. Illustrated. F.C.H. Glass industry of Ohio. Arthur S. Watts. - Ohio Slate Unit. Eng. Expt. Sta. Next. 11 (4| 10-13 (1939).-- Ohio is the third largest glass-producing state and has twenty glass plants. In 1797 there was a glass plant on the Ohio river; by 1823 they were all over the state. The production of hollow glassware has increased twenty timeS' since glass blowing machinery has been introduced. Ohio is an important producer of flat'glass. Today this is drawn from the tank as a continuous flat sheet. Other important products are electric tight bulbs, fiber glass, and glass blocks for use in building construction. W.D.F. Plant laboratory. K. Sfixgler. Tonind.-Ztg.. 32 f44| 492-93 (1938).--The plant laboratory has the follow, ing tasks: the testing of raw materials and half-finished and finished products, the working out of new formulas, improvement of old shapes and construction of new shapes, and local research. W.K. Prevention of industrial dermatitis. J. V. Klaoser. E. R. Gross, and H. Brown. Arch. Dermatol, c* Syph- ilol., 41, 331 (Feb., 1940).--Much of the industrial skin disease is caused by the methods of cleaning the skin. Skin cleansing, methods and materials used, and the use of protective applications are studied. Formulas for eight protective applications are given. Substitutes for me chanic abrasive soap are listed. Various kinds of soaps and detergents, such as triethanolamine soap, naphthenic acid soap, and sulfonated oils, are discussed. The detergent properties of the vegetable meals are not sufficiently appre ciated. F.S.M. Pyropbytllte dust; its effect and control. M. F. Trice. Atner. Inst. Mining Met. Engrs. Tech. Pub.. No. 1179; Mining Tech., 4 [3| 13 pp. (1940).--North Carolina is the only commercial source of pyrophyllite at present. Pyro- phyllite occurs associated with quartz, together with chloritoid and sericite. All the pyrophyllite marketed is ground; it is classified by air separation. It is mined 2>y open-cut, glory-hole, and underground methods. At only one operation has work been carried on since 1920. Underground, the free silica content of the dust is 35%; S0% of the particles are less than 3 microns in size; dust concentration rises to 500 million particles per cu. ft. when drilling. X-ray examination was made of 101 workers; of those with over two years' exposure. 35% were affected; two died. The lesions were the same as those produced by free silica alone. The threshold dust concentration allowable underground is 10 million particles per cu. ft. Drilling is done wet; stopes are ventilated by "ventubes." Above ground, tight housing for machinery and exhaust ventilation have been installed. These procedures give the required results. W.D.F._ Recent Commission findings. Anon. Ohio Industrial Commission Monitor, 13, 41--12 (March. 19401.--An employee of a steel foundry worked from May. 1922, to June, *1939. in the cleaning department in the foundry, where his duties required him to remove hardened sand from castings by use of a pneumatic hammer. A dust count in the room showed an exposure well below the accepted safe standard, but the dust contained approxi mately 20% of free silica. The Claims Referee was of the opinion that the exposure to silica dust was well estab lished. and the claim was approved as compensable by the Silicosis Referees. Acting under the provisions of an amendment to the Occupational Disease Act effective May 20. 1939, the Commission granted an award of $6500 to the widow and minor children, payable at the maximum rate of S1S.75 per week. F.S.M. Recent development! in relation to silicosis. Leroy U. Gardner. Ind. Med.. 9, 45-51 (Feb.. 1940).--Certain tentative conclusions derived, from experimental work upon silicosis in progress at the Saranac Laboratory for some years are recorded. As a basic doctrine. G. con siders that it is still true that only certain forms of free silica and the group known as asbestos (fibrous silicates) / i i r* *: V. Li* & 7v *%\ 1 Jw* 1* I*: * . ' i > %* (> r-. - - -7*1 A l.j ;> >**.! 206 Ceramic Abstracts Vol. 10. No. 55 arc capable of producing fibrosis in a normal lung. The trend of tome of the Saranac experiment*, however, has altered certain concepts previously regarded among re search workers as fixed. Inhaled chrysolite asbestos fibers now appear to be irritating, not because they are silicates, but because they are stiff fibers, mechanically irritating to the lungs. Grinding them down very finely so that few of the fibers were longer than 2 microns prac tically destroyed this irritating property. Even with an average atmospheric concentration of 125 million particles per cu. ft. of air. no fibrosis developed. It the effect of asbestos on the lung were entirely chemical, a decrease in particle size might be expected to increase tissue response. Large particles of free silica have little effect on the body, but small particles increase the reaction of body cells. The histology of early asbestosis. as detailed by G.. does not suggest chemical injury. Among dozens of different silicate minerals, only the group of five known as asbestos are unique in having fibrous structure and in being com- raooly recognized as pulmonary irritants. The group varies in chemical composition within itself more markedly than, as a group, from other silicates. Chrysotile asbestos has the same chemical formula as a nonfibrous silicate, serpentine, which is physiologically inert. In mills that fabricate asbestos textiles there may be much fine dust, but if the dust is composed of serpentine and very short chrysotile fibers, clinical asbestosts will not develop. Free silica dusts, unlike those from asbestos, cause a chem ical form of irritation in laboratory animals. G. describes the two histological stages which characterize the tissue reaction in such animals after inhaling excessive quantities of pure quartz or dint dusts in an extremely fine state. In human subjects, only cases of rapidly developing silicosis show evidence of this two-stage reaction. The solubility hypothesis, however, hitherto rather widely used in interpreting silica reactions in the lungs, is de clared to rest entirely on indirect evidence. It has never been passible to prove that silica dissolved within the body, because the soluble material immediately combines with local tissue elements. Soluble silica detected in the urine and the blood is now generally accepted as more likely derived from food and drink than from inhaled dust. G. describes many of the Saranac experiments whose outcome individually and collectively is difficult to reconcile with the theory of silica solubility. So fibrosis has ever been produced by single or repeated in jections_ of soluble silica in its various forms. Evidences of specific toxicity exerted by silica upon living tissues have been manifested through long series of experiments last ing years: many concrete examples are given. Intrave nous experiments immediately fatal to guinea pigs produced no symptoms in dogs. The toxic effects of quartz have been more or less neutralized by adding small amounts of different substances, e.g.. colloidal aluminum hydroxide which gives complete protection in a 0.03% dilution. Particle .size is discussed as having new and unexpected relations with both highly toxic and merely slow fibrotic conditions. G. is cautious about drawing final conclusions from animal experiments alone, but he does begin to cor relate his experimentally derived facts into a coherent silicosis etiology. K.R. Relation between the thermal expansion and the proper* ties of ceramic products. IV. H. Earhart. Ohio Slate L'nio. Eitf. Expt. Sta. Next. 12 12| 25-28 (1940).--The composition of a body may be modified to ohr.xin a desired thermal expansion. The thermal history also affects the thermal expansion; certain compositions fired at low tem peratures have less expansion titan the same hodv fired at higher temperatures. Thermal expansion may be measured directly on a bar or by the interferometric method. Bodies with a considerable amount of highexpansion quartz in low-expansion clay may show doming tendencies on cooling. Beta-quartz expands on cooling and may also set up strains. The abrupt quartz inversion poinc at 575 *C. may be destructive. Quartz and days have fairly uniform thermal expansions, but the feldspars are variable. Hotel china, sanitary ware, and ffnor tile ail have thermal expansion curves lying close together. The quartz presenc does not seem to affect them. A quartz grain shrinks more rapidly on coding, and it is thought to pull away from the remainder, so that it docs not fill its recess in the body completely on cooling. W.D.F. Report of Committee on Ceramic Education. N*. \V. Tavlor. Chairman. Bull. Amtr. Ceram. Stic., 19 [61 220-21 (1940). Report of Committee on Publications. John D. Slxli- vaX. Chairman. Bull. Amer. Ceram. Soc.. 19 Jti) 222-23 (1940). Report of Committee on Research. As.THt.~R A. Wells. Chairman. Bull. Amer. Ceram. Soc.. 19 (HI 214-lS (1940). Report of Committee on Sections and Divisions. M. E. Holmes. Chairman. Bull. Amer. Ceram. Soc.. 19 [ri| 221-22 (1940). Report of Committee on Standards. John W. Whitts- more. Chairman. Bull. Amer. Ceram. Soc., 19 ftJl 213-20 OWO). Roentgenologicaspects ofbronchomycosis. K. P. Docs. Radiolotj. 34, 2S7-75 (March. 1940).--The signs and symptoms of the bronchomycoses are similar to those of tuberculosis and they are often at first thought to be tuberculous in origin. D. describes some of the more prominent Roentgen signs of (he various bronchomycoses. F.S.M. -Silicosis. E. R. Hayhvrst. Merck Rept., 49, fi. 3. 9. 23.30.32 (April. 1940).--H. gives an exceilenc short review of silicosis. F.S.M. BOOK Engineers and Engineering in the Renaissance. WilLrAM Barclay Parsons. Williams 5c Wilkins Co.. Balti more. fifil pp. Price 38. Reviewed in Science .Vrr Letter, 37 [12| 192 (1940).--P. discusses the amazing engi neering achievements produced during the Renaissance. P.G.H. PATENT Coating and coloration of granulated materials. N*. P. HarshuERCER(Bakelite Building Products Co.. Inc.). IT. S. 2.202.002. May 23. 1940 (June 2. 1936).--A roofing granule has on the exterior thereof a coating comprising a hardened high-alumina cement containing principally calcium aluminates or calcium alumina ferrites and sub stantially free of free lime in amount to produce objection able efflorescence in exposure, the surface of the granule being also substantially resistant to chipping and wear and stable with respect to a bituminous bond. ; ; j i I I i i ( I 226 Ceramic Abstracts Vol. ID. No. It Iteen taken of the advanced training centers in heavily in dustrialized communities, showing that there is evidently -mall demand for this held of practice. F.S.M. L Lead content of human blood. Q, Lead aa a poison. J. N'. M. Chalmers. Linen. 238, +47-30, -hid-(SI (Afarcli 0. 1040).--Tompsett's method of determination was used. Stood was obtained from Jo normal people and 30 hospital eases, all with no known exposure to lead, and also from 44 factory workers with a definite lead exposure while manu facturing white lead and storage batteries. The blood of the controls showed a lead content which varied from 3U to (hi Mgm. per 100 cc. with a mean of 57. The lead workers, who presented no symptoms of poisoning, had blood lead values ranging from ih) to 1!>J gm. per UW cc. .with a mean of 104. Augmented concentrations of lead in blood indicate increased absorption of lead but do not con stitute evidence of plumbism; they are a useful estimate of the degree of exposure. Clinical findings must still continue to govern the diagnosis of lead poisoning. There is a discussion of the problem and also of the value of milk in the diet of lead workers. With a high calcium diet, there is less lead absorbed from the gut than with a low calcium intake. Sines, industrially, most lead enters the body through the lungs, the calcium probably acts by helping to fix the lead in the bones and thus prevent it from circulating in the blood. Though of great value, blood studies and similar biochemical investigations must not be given too much consideration. F.S.M. Lungs of cement workers. S. Caccvri axo L. Dt- Prisco. Folia Med.. 26, 7-J0 (1040).--A review is given of Italian literature on the subject which seenu to give a less favorable picture of the health of cement workers than is found in other countries. Histories of seven cases are given which show silicosis in grades l and J and emphysema. Tuberculosis was not found. F.S.3L. Manufacture of fired days (brick, tile, and pottery). A. Colthox. ArTile. No. 197. pp. 13-21 (1939): No. 193. pp. 5-9 (1940).--C. discusses the raw products used in the manufacture of fired clay products, the formation of days, and their characteristics and composition. ALV.C. Mechanism of development of lead anemia: IV, Physiochemical nature of the splenic and liver substances which decrease erythrocytes. S. Kist. Jour. Med. Coil. Keijo. 9, lUl-in" (1939).--After injection with lead acetate, the spleen and liver seem to contain some specific chemical subscances which are able to decrease the number of erythrocytes. K. attempted to determine the physio chemical nature of these substances which were obtained from the splenic and hepatic veins after injection of the lead. The anemic action of the splenic substance disap peared after heating for an hour at 100*. The substance was soluble in water, but did not dissolve in ether and alcohol; it was adsorbed easily by animal charcoal or kao lin. Its action was also retained after ultraviolet radiation for 3 hr. F.S.M. Metabolism of nudeoproteins in lead poisoning. C. Michettj and F. Molrixo. Ross. Med. Applitata Lavoro Jnd., 10, 562-32 (1939).--Original research on ten cases of lead poisoning shows that there is a pronounced tendency to uric acidemia: this becomes more acute as the poisoning tends towards chronidty. No relation was seen between ;the degree of uric acidemia and kidney function, and no such connection is likely to exist in cases of recent lead poisoning. F.S.M. Nature of anthracodc foci. Experimental research. A. G. Savellini. Folia Med., 26, 21-32 (1940).--S. ; gives a review of the literature and of the views of some ; French and Italian workers who are of the opinion that the greater part of the "anthracotic" pigment in the lungs is not truly anthracotic but iron of hemolytic origin. Animal experiments by S. lead to the conclusion that car bon and iron partiripate in the common anthracotic focus; | some contain carbon and some iron only. F.S.M. Occupational dermatoses under the Illinois Workmen's Occupational Diseases Act. H. R. Foerstex. Illinois Med. Jour., 77, 79-85 (Jan., 1940).:--After analyzing various sections of the Illinois taw. F. concludes that "any skin disease may therefore legally be aa occupational disease in Illinois." F.S.M. Preventing economizer corrosioo. F. J. MArrnEtvj. Brit. Clayisorker, 48 [3731 :132-54 l 194U).--M. discusses the causes of corrosion and gives suggestions for the niainccnance of the economizer. R.A.H. Priceless possessions. L. Grcexrurc. ' Aat. Safetv AVer. 41, 20-27 (Jan.. 19401.--There were 1843 cases of compensated eye injuries in New York State in 1U33 .mrf (he cost was 31.163.000. Of these. 80^ were caused by foreign matter entering the eye and could be avoided by the simple and cheap method of wearing goggles. Ventila tion controls are needed for eye hazards of toxic dusts and fumes, and in the past year the Division of fudustrul Hygiene has passed and approved 2000 sets of plaas for uch control in factories. Special goggles are needed for protection against radiant energy, and fatigue of the eyes can be lessened or eliminated by proper illumination. G. discusses these sight-saving means and methods for pro moting their adoption. F.S.M. Two fatal cases of pulmonary asbestosis. E. C. / Vtct.tA.vt. Rais. MM. Applicant Lavoro Ind.. 11, 26-32 (1940).--The first of these cases concerns a woman who worked for thirty years in a factory using asbestos in the manufacture of cord. The second woman worked for seven years in an asbestos factory. Her susceptibility to colds increased while she was working and she suffered all her life from bronchitis and asthma. She died at the age of fifty, with symptoms of a lung disease, nearly thirty years after having stopped work. The autopsy showed interstitial sclerosis of the lungs and asbestosu bodies. F.S-AL Unemployment benefits no bar to worlmen's com pensation. Axox. U. S. Dept. Libor. Monthly Labor Rev.. SO, 670 (March. 1940).--An employee .receiving unemployment benefits under the Unemployment Com pensation Act is not disqualified from recovering com pensation for the same period under the Workmen's Compensation Act, according to the Supreme Court of Michigan. F.S.M. SEPARATE mUCATIOSS Basophilic Aggregation Test (for Lead Absorption and Lead Poisoning;. Axo.v. Ohio Dept. Health. Adult Hyg. Div.. 194U. 7 pp.--The technique and interpretation of results of the basophilic aggregation test are given in a concise form. F.S.M. Legal Aspects of Engineering. W. C. Saoleo. John Wiley tc Sons. Inc.. New York. 631 pp. Price 34.00.-- This is a direct application of the case method to engineer ing problems, three hundred cases being selected alter 6500 legal cases actually dealing with engineering problems were carefully analyzed. Cases dealing with compensation are of the most incerest. S. gives a general discussion of the subject. Cases are given to Illustrate the following points: elimination of defenses, hazardous employment, employer- employee relation, accidents arising out of and in the course of employment, proximate cause, award, dependency, and jurisdiction. F.S_iL Manual of Industrial Health Hazards. J. B. Ficxj.es. / Service to Industry. West Hartford, Coon. 175 pp. Price * 34.00.--F. presents methods for the evaluation of indus trial hygiene exposure resulting from many dusts, vapors, and gases. The first chapter gives principles which are basic procedures for making surveys and describes sam pling devices. The other chapters are given over to the ma terials or groups of materials which may cause industrial disease. For each substance. F. gives the occurence and . uses, certain physical properties, the clinical symptoma tology it produces in man. the physiological responses oc man to various concentrations, the concentrations allow able in the air of the workplace, and a simple method of estimation in air. Numerous references are given. _ An ap pendix includes useful constants, formulas, and. instruc tions for the preparation of standard solutions. i-H m HUNTER GAS BURNERS Latest and mote efficient vortex Burnert for every pi Gas 9urners with Oil Burners incorporated Gat Burnert taking two gates alternatively PflWFR nas ECONOMY CO.. HURST, NELSON & CO 6uildr a?, MOTHERWELL RAILWAY ROLLING S OF EVERT DESCRIPTION C*I'?*.*'(*. i IV Cu'tiWp (Cl we rows eon Simple mie hm ead Cel Trtdit le*4ev, tfttmktr g tm THE IRON & COAL TRADES LftXDOXf SEPTEMBER *. 1339 REVIE Iron-Ore Extraction in the Midlands* OPEN CAST WORKING AND UNDERGROUND MINING AMETHODS OF StURFACE WOREINC LL ironstone ia the Midlands vu The appended description of iroo-ere extrac Tho siso of bill sod dslo varies slsc with tho depth of overburden, since the excevetor used varies generally origiuaUy goi by hand either ti out* tion in the Midlands has beee takes Crow the depth of tho overburden to bo wor cnp or not more then 15 to SO ft. beloRweport* of the Committee on the Restoration eon therefore" talk of a ** normal ** i the surface. Tlie reinstatement of such lead of Laud Affected by Iron Ore Working, and sad dolo for a particular depth of for agricultural um immediately working preaented no difficulty. after the Mo great deals with methods of removing the over if it is understood tbet only s vsry g tionship is meant. The general wo- mtuei of subsoil had been disturbed; the topsoil waa merely thrown on ooe aide and burden, and winning ia underground workings matter of importance in connection costs of levelling. When tho cut is a final gullet is left. This may ba at then returned without any coat for haulage. of 200 to 300 ft. wide and CO ft. do At the turn of the ' century small steam navvy feUoviag up behind dragline A and load- may form a considerable difficulty i excavators with a short^rm jib were intro . ing the ironstone into wagons B. The fees st D access to the quarry, particularly for duced for the purpose of removing the over burden, but all land waa still restored by hand. When a quarry was about to become too deep for restoration it was abandoned or aiad. Excavator* were then Introduced for removing the ore itself. In the expansion of gradastly recedes as the ironstone is removed. The working is Hks e movable cliff. (2) A short jib exesvstor may be used (a conjunction with s conveyor ss ia Fig. 2. Th* exear star A removes overburden from tho face B sod thn empties tho load into s small truck, or dumping tram, ea tho steel-framed restoration work. Local Objections to Largo Exc It ts the operation of these moeh: has slarmsd local opinion aad which attention to the whole question of i working of ironstone in chi* country, development due to the War, the American conveyer at C. This runs up to the other sad reAction to tho coming of tho largest long jib and mechanical digger with a wide at D end tips over. Tho function of the con has been to suggest that they are not dumping radius waa introduced. About this veyor is therefore to move the damped over- It is soon that ironstone won be time some areas were first left unreetored. harden ewey es fer as possible so that there is machines cams sad it Is suggested : This was. at first not so much due to technical difficulties as to a eompeny going cut of business. oa danger.of tho-navvy which is removing tho ironstone becoming buried. Tho oytrburdea is damped by the cmve/or in a ridge end furrow formation similar to that which results from ought, la view of tho devastating co to bo a reversion to elder methods e covery of yet newer ones. If it is poia reply that ironstone could not be got The position became serious vhta. Is the the use of e long jib excavator but in e rather ally at 60 ft. depth by the old met thirties, Stewarts ead Lloyd* left Scunthorpe more wavy line. sometimes argued that, if the prorii Fto. 2.--Sxobt Jo Extsactos ad TsA.'tsroaTts aad came to Marthasta. Sisco they were late* (3) Tho overburden caa bo romoved sad pul to it, they oould invent new moth camera they found all the areas of easily got ore damped by a bog-jib exeavetor. Tho aketcheo would abolish or modify bill and dale, cootrolled by other- ftraa, end they were forced (Fig. 9) are of a 9<ub. yd. excavator at work. engineering devebpatents as they app* to lease arses of deep overburden. They bsgia Theso machines are the Urgaat ia Europe, and Committee from tho evidence put bet cork os those with as elactricai sxeavator they have aa output of about 500 tons per hr. included: -- which, with a 9 cub. yd. bucket (l cub. yd. each. In fact tho whole area assumes the aspect (t) Aa attempt might bo made to io represents very approximately 1 ton), a dump-* of baring gigantic furrows, which arc locally excavator. Tho present performance ot ing raJiua of 101 ft., and a dumping height of known aa " hill aad dais." Tho ridges consist function of the radius of tho jib ar B ft., could duel with overburden up to shout predominantly of subsoil, and in them tho top angle of repose of the dumped soil, 60 ft. in depth. soil is irretrievably lost. The else of these cause these two factors are fixed, that Ironstone is woo by a number of different furrows depends na the sixo of the navvy used dale formation occurs. If the length machines whose operations have somewhat for the excavation. Where tho largest navvies could be varied slightly with each hue different offsets. They include the 'dragline are in use, the distance from crest to crest is than- hill ' and dale of the present which works on the principls of a rake; the fnm 40 to 50 ft., tho doptli varying from 10 would not be formed and a surface wo earsvtor or ** digger " with a short arm (the ft. to 15 ft., but where smaller excavators hare which, if very irregular, would be much * jib ") dumping in U i conveyor or wagons; been used in the post, the crest to crest distance level. II the length of the jib were . tbs long*jib sxeavator which dispenses with ths is betwsaa 90 ft. and 30 ft., sod tho depth from however, ae ae to give a choice of tsttor, and the Lubeekar (tend) drsdgsr which U ft. to about 10 ft. The shape end sixo of tho which each bucket could bo emptied, tt can damp sand or other very light soil evenly. hills end doles depend not only on tho typo of of the entire machine, whieh U tires The drodgsr creates no problem of levelling be Machinery used for putting tho material across, 500 tons, would bo increased to an imp- muse of the number of smell backet bads but also so ths angle of repose of tho dumped extent. Further, if any attempt were damped, but for this reason it is ooly efficient in material. Ths natural angle of repose of any dump malarial anywhere nsr the exeat seed or light soil. There in e greet number of particular soil composition will generally only be angle of repose of the tipped soil woi combinations of theee machines, with or without found where it is free to trickle; e.y.*, ua the that the excavator itself would be btirie baed labour, which are used ia different quarries, slope of the dumped material stretching down (2) A new conveyor might be Jcsic and it would bo difficult to giro a complete tn the quarry floor. Measurements are often position of which could be altered b*tw. account of them. Tho following ore descrip mad# of this eagle for different materials and load plseod on it by a smell excevat tions of tho work in three quarries which are "uftibinstiont of materials, because it. is this witness suggested this, but the Commit- representative of certain typical conditions. angle that determines tho distance between tho it an unlikely development. The prw. (11 A 1( cub. yd. dragline et A (Fig. 1) re tnp of the dumped overburden and the fort of ecyorv eaonot be used where there is moves the 2-ft. overburden (including 9 in. of the excavation. These measurements show that of overburden of more than 40 ft. b topsoil) and deposits it at C in i rery shallow an average angle of repose is 1) horixontally to l the strain which would be imposed * ** hill and dale '* formetion which ia thvnjjvellud rrticslly, although it may be flatter in boulder arm of the conveyor when tits truck was be the |th cub. yd. dragline st C. The opera clay where there is s good deal of slipping and sway from its point of support. It tion is then completed by s 4-cub. yd. steam steeper is limestone. The angle of actual hill be easy, therefore, to design a convey and dale is nearly always flatter then the angle would produce better results with ea ov of repose proper because the materiel is partially of 0 fV or more in depth then ere * V*. tun--tf OSn, WJLS. |PH U Mt ) Ttrl Imn, lli|ir. leeAee, spread ia it is emptied from the eacavotor. tho present one with so overburden of 336 The Iron and Coal Trades Review September 8, 19 Fatalities from Silicosis and Asbestosis have been made therefore to 6nd ami int Acicat luUtitvtn for 'ilicoow* materials THEIR INCIDENCE IN INDUSTRY tLEZTTL . a considerable extent; ia others it is confi Tho problem* UMClItCa With suicoaii end UMIIMII imonglt . industrial technical experiment* in the processes worker* are receiving close attention. The former ha* tended to increase* Alumina for tint ia china bedding; (2i ai .nd the l*ltcrf on bJane., to decree in recent year. SUSiES il UTi Eft in*; (4) ooa^Uteceoa material for kies A SECTION' of the Anoual Report* of ths oecwpatiow wax that of impairing the silica brick used ia the slew cooling of stool; and li Chisf Inspector of Factories dealing Uoinga of strol furnaces or eoarertora, ooe a pot wlireoua material for silica bricks for Unix with health refers to the question of dust * ***" one an engine driver in a#d other furnaeeo. and Its edeets, including silicosis and * *^,r| works, and one a grinder of rt ~ ~ nshratmit - It is pointed out that for some '""Wy bbrraicckk*s,, tthhee rreemmaaiinoddeerr bbeeiinngg associated 7rrjrv p"rr,a?01 cm* .rastassraf <l*atU fmra there two tu*re. which have i processes in the getting, crashing, -grinding " . .. . .... . Hydraulic Stowing in Indie *(C--o--n-c--lu--d--e-d- </--root jwj----3--3--&) been Inveetigeted by the Department, have ^o,^, ,,iu Lot. ^LT been given and brought up to date. Theee ing to the Inspector', knowledge .nd iore.tigxt*d hTM the hr. figure, have been .peciaUy u.etul from the done, th. in ioo. The figure. rireo on practical point of view ia aiding the matalla. d " OtUr Com, of nmi. are th. num- 0f vtml; but in dry perioW lion of preventive measures of the necessary her of esses in kick Fibre'll of the Un w |be<| a* u I*,** ha, ^ nc; standard in processes exposed to risk. Of WV "t#r*d V** certificates ss the *cJ#ai| $tt|5ng w4ter is obtain*! direct fn much importance and mors general interest. ***** * thT**T"?ur** "JJI WP* river. The suetioa pips is submerged however. Is the trend of mortality rates from J;l0d V -"t*jrt4**T.1, " gitrar General. hf * flangt to tbo pump the.* (ii.en. with or without tuberculnii., , ln,,Mtlg*t* alt th* ,r lo-rend by a winch mounted which does, when eomp.ri.oo i. mad. aft., T J u,. `^ ,,hi* h" *_ . .1 m ..__ . majority the occupation of tlie ucceisml appeared QO needed on suetioa side, in a number of years, reflect the effectiveness^of not to kart involved rUk from *iliea or asbestos. aUanutr of sand ta water U reeutaU'd et the preventive muwra installed. For this and it h nil raesgnired that flhrnai. may b* du. 1 prem' the d.liv.ry aid* of tht^oump th purpoae. companion of the figure, of tiro ta nan ether than the inhalatina of dnt. ani, ,,attr i ccnre.rd hr m.an. lucco.ir. year* ia of no raiue aod wni.time. Thoae return, are intliipanubl. .inre, from tiin. ,rlIIO<,m| He.ibl. how pip.' ta tin* at mmlendillg. tn tiiu*. Umy prnrid. the .tartinc pain, nf .tori (dpr, in PUt. ta io-lt. Ir.mthr, fi.t- Table I shows deaths attribated to silicosis fortlior is*atigstion which provides valuable Victaulic joiats; tbe pipo raaie is cart (with or without tuberculosis) duriog tbe last information. (jat, ;n ((, stream. Tbe pipeline dflin T.ic* I.--OmOU from F!*romo of tit f.utf. iotMiof Sllico.l. and Aabeatosls end Cancer of the- renil-.at.r mixture into a reoical wpar: Silieoms end dskrstafM (gagloW and (Talwl, Lung thf rate of 9 tons per min.' Tho uni 193MI. Dmmm and ioduasry. 193*.; 103*.{ 1937. Silico>is Iftcfmctorin indoaerwe.. It 9 19 1035. 12 Tn reretil yean tbe suggestion has been made in medical publications that there is some r*la* tionship between silicosis or asbestoris and can* r.o.rj of..th.e lo_n_"g. T_h_o_*q u,,estion_is a .diffic.ult, one. mixture is fed on to screen platps vith lioic*: the velocity of tho incoming mix: so reduced that taad is deposited in the of tho separator and fairly clear water tuhrungnh tobo skuaotwesi aast wthe nsiduens eoif *thue* wumpy "i f `nA "* r*t lanre T,,. ,`,,J mUliaM to. much nhr, how. Pottcvy. maoalacturoof SaiwUtono qoarfying and ilemisf .. ftandstowo mMooa \T<al irindinc .. Band btortinf .. M 4ft *1 ts 14 47 G4 43 il9 a* in 24 ! i* 10 13 45 r^g?iJr r V dr*". "n'l"*""* u. dolirl direct to tho Ml conr.ro 27 .5* 25 ITS "fr th" .*'< the and i. further dewatered on a drrin to he covered is wuior than appears at fnt sight. Major points which win have to be settlod are: Sond*DryingDovlco 1 Dore ..lire or uhretre or tit. Ibreri. of th. lung ^ U>ici.,,.ur ntiature-hy wght Std diwMiii and rl--a thoy predneo loud to Inhih. reneor of tho lun* m>ulj. 4 part, ,,f ta 1 of oarer- isfofcaMinc* Stone. prhWr. Sint, and sand mtahing Semrinc powdora, BMuueiunof Ensrosl and fUu 1 i 1 49 14 2 3 or re prodore It? If tho latter do either of frenl 'lhe bottoot of the reparator thre there ton relwtance. act re .peeilie rarcinnceme pnnmd relvo over a iluiributing plat, o * acenu like tar, or I. it that the direnao they pro- 4 ft wija drrin, halt. Til. drring belt r 1 duco only prepare, tho reil for th. aeonrr.no. of of a wrie of tlulloo Iran, * 'io. deep. cancer? Th* following informatinn hu been on mlU-r-t; each tray contain, a niixt makers 1 nollretrd from th. Iiupector't rreorri.. No can* alag which ia kept ia place hr | in Coapo oiixrr (Tripoli).. t -- -- -- ku hren inrludcd in which a poat-morrem ...mi. ln,,, pl.tn prforared with i in. hold, Abr%sire.wbeel mans. nation haa nnt horn mad*. Holt ia driven at a apred of 10 ft. pc Mon ! Millstone dnrmne 1 Slats dressing with sand " " Elsctridan as stool foundry . -- Slate quailing and Among M3 fatal care, in which mlicoai. or T|,rr. roll.ra or aqureuc. or. pbred cquidi l 1 rilicrei. with tuhcreoloai* waa prerent, cancer ef a|,,,,g tli. upper belt eurfac. and a ae: the lung wre umxiated in 23 caw. (2.1 per .roiiga placwl ia wrin along th. hell tu 1 emih). Of there 23, In IT it waa oonudrrrd that ,aod 0r.r a. it ia carried forward. Th* th. cancer waa th. primary retire of death, and and prongi help ia th* d.ararering of th, divssirif S 1* 7 ia 6, rilicous or mlirou. with toberenloaia wfdbt th* alag ia tha traya allow, water ' Crmaito qoanying and Among 31T dreth. which were iaroatigatrd dur- hot aot tho read. ditssin* 1" Toooc) mining (sowago I * lag th* rein* period" owing ta tha pnreihiliiy of n,, land ireuiag from th* drying beilicoaia being prereat, preUmortam reanunation toini b roluo* appmximatalr 10 per ei works, sic.) .. Grave diggers .. Casl minifig Gold mtoog (Sooth Africa) * 1 111 I* 120 4 t o 137 15 t 177 12 rerraM ao riUereia hut renere of th* lung waa vaUr. 'The rend i. delirerml from th* found in IT care. (4.0 per rent.). th, drring' beit direct on to a 2&nn. tro Similarly with rebretnaia. among JOS fatal h,u eeareror which delirere it inu th. care* ia which rebretnaia or reWou with hunk.r. `Th. hrit eonr.ror .l.ratre th. Tin mining 29 24 20 20 tubmulam* waa prereat. renew, of th* lung waa w iB (t ran to th* top af fti* b lire ors (has matito) areaciatad ia U eaaee (11.6 per coat.1. Of there m u^oatit of thi. grade oalr fairly dr mining 12 . 15 13 12. ia t it *u eoomdered that th* rearer wu nf| h, rarrieil. Lead mimne ............. Copper mimng .. Barytes mining Mintftg engineers re2re s -- rer1e 1 1 11 11 i 3 2 the primarv reore af death, and ia 6, oehretoai. The rend is deiirered by tli. belt ronrer or uMflai. with tnbereuillamwiisi. a .preiiMc con.troctcd hanker holding n: I. i. el.ar from there incomplete figure* that Mal'ri, y .000 ton*. Oo the omlenide extended inquiry and collection of data and hunk,r th. ,!nnle roil .rm.nd wl.l Total: sflieosis 392 3*5 415 j 430 ereluatlnn of ago incidence and ago distribution ,af|1| of th, ur;,| ropc.nr gr Asbestosio........................ 15 II 13 ft are aMewary b(or* any eoneluaioaa rea b. ,Mirwcd from the mpe.' 0 arrired at. ,l,|n there are T ehutre which drlirer > Tho importaoc* of th. more careful pot- |h, ,,,lrkct,. th. regulator at the bottom Other cases of ibrosit 535 544 534 | 403 mortem reaminatum la emphaaiwd hy a recent <hut( mntrolling th# rend outflow to the ---------G---r-a-n--d--t-o--t-a--l--------------9-4--2----1---9-2-H-----1--9--6-3-------0--4-2--- care in which saked-oy* examination revealed ja of lv advanced ashvstests, out what appeared to j,ajflnrt a ,in,-f, wvight. ,Tpa_ ,,,d i, kept in A ene-ton capacity plac hn four rear*, togrther with lhe imlnitrioa con- h" * email btaod dot in, o hrnnehoa tiled in i tin. through on* of the ihut* i v ,. . o* | an mtcmampiral txaminauon to b# a rarvtnoma, r.erue. il. I*n factur-y ,rare,*, th* enAur,e .of dextli and al* aftwthrr _ra_** .i w.hfic_hK filieosis, ttnnll-s,rr.- hre Iwen Imrn, nut hr .lrpartn.rnl.-U ...rertiga- ^ primary carcinoma were all prereat turn. Tlie raru'ty of industries will l*o noted, ami if spam psnnittod tn giTe dotai! Uts pro* tw nrciipntionl history in each cam, tho vory widespread iialtiro of tho risk wonld ho still moro lua*s Substitution of Siliceous by Materials Non-SIHceou* Luxemburg : Iron and Steel Output 1939 Pis-imii ontpnt *.in .IfUtcmbure in JmIt 1*4.JMA metric tons (1M.SM tun* in Jim* i. riiicnt. For example, refrartorios* imlu-nrics ?t9et99n ;n which tho risk of silicosis is 117.904 tons in July. I9M1. 9tml pm<lMci: iactudo amongst tho 52 faUlitios threw who**- and uneontrollablo nr only partially ma 177.649 tons in July, scsintt IS7.W ton* : w*ti.">^7tTIn?"" T"* tmllahl#. tho prevention of Mlicosi' lies vithvr and 110.-193 too* in Julv. 1914. A total of U-"" in luUti-t.uti.onr.hy ih__a__r_m_ <l_r_e_.___m__a_t_ari-aiU-i.o-r at th. n__a__c_r_e__w___ir_e_ in LWi.arert no. JTu..llrye 5*1i . ftus f ublUh4 to promoto owdd thought upon *d conconiutg (duiiml nd*CMO nd traumatic 4tr9ry. To that end it will contain r' newt Hums, reports, digests, or presentetlons, together with ^Itrors* comments. The editorial pot- cy cs to encourage frank discussion. Da this basis contributions are invited. tUfV S.PU.QS. The J;. rs wHJ exercise cere in check* Sng on the accuracy of date printed, but in eQ other respects articles end opinions of which expression h allowed ere the opinions of their authors--the editors reserving e ell cases the right to comment on the same, Sn the cur rent or any subsequent issues, as they may be inclined. | The Journal of Occupational Diicaici and Traumatic Surgery With which are consolidated "The Industrial Doctor'' and "International Journal of Medicine and Surgery." The Science, the Law and the Economics of Industrial Health /olume 9 FEBRUARY, 1940 Number 2 General Motors Corporation Medical Conference --Dayton, Ohio, November 2 and 3.1939-- HE recent Medical Conference of General rMotors Physicians, held at the Biltmore Hotel, Dayton, Ohio, November 2 and 3,1939, omprised five meetings and 18 presentations. The Program was as follows: Thursday, November 2: v/TORNING Session: Chairman, M. M. Skates, MD, vJ- Medical Director, Frigidaire Division, Dayton, l "Recent Developments in Relation to Silicosis," O U. Gardner, MJ3., Saranac Lake, New York. A Flan tor the Control of Tuberculosis in Industry," Iax Burnell, M.D., Medical Director, AC Spark Plug ivision, Flint, Michigan. 3. "X-Ray in Industry," M. William Curt. MD, 'urley Hospital, Flint, Michigan. 4. "Preliminary Report on Hygiene Studies of Weldig," L. B. Case and V. J. Castrop, Industrial Hygiene ^boratory. General Motors, Detroit. \FTERNOON Session: Chairman, A. L. Brooks, MJD.. - Medical Director Fisher Body Division, Detroit 3. "Recent Developments in the Occupational Dermaises," Marion B. Sulzberger, M_D, New York City. 6. "The Course of Disabling Morbidity among Indusial Workers, 1921-1938," William M._ Gatafer. D-Sc., 0 S. Public Health Service, Washington,* D. C. 7. "The Industrial Nurse," Harold M. James. Mi), Medical Director, Delco Products Division, Dayton. 8. "The Doctor's Part in'.the Personnel Program," eorge A. Coburn, Personnel Director, Delco-Remy Divion, Anderson, Indiana. J*VEXING Session: Chairman, Walter M. Simpson, M. D., Director, Kettering Institute for Medical Re- ^rch. The Miami Valley'Hospital, Dayton. 9. "Relationships of Industrial Medicine to Private .'actice," Stanley J. Seecer, M.D., Chairman Council on dustrial Health, American Medical Association. 10. "Unfinished Business," C. F. Ketterstc, Director rneral Motors Research Laboratories, Detroit riday, November 3: ^TORNING Session: Chairman, G. L. Bird, M.D., Medi- Director General Motors of Canada, Ltd., Oshario, Canada. U. : '1 Practical Approach to Supervision of Mental ?alth in Industry," F. S. Parney, MX)., Chief, Division of dustrial Hygiene, Dept, of Pensions and National alth, Ottawa, Ontario, Canada. ^2. "An Example of Industry's Participation in the "ti-Syphilis Campaign," P. J. Ochsner, M.D.. Medical Director, Fisher Body Lansing Division, Lansing, Michi gan. 13. "Study of the Factors of Employability, Especially Disabilities and Infirmities of the Elderly, and Problems Arising from Employment of the Same," George A Paul, M.D., Medical Director, Hyatt Bearings Division, Harrison, New Jersey. 14. "Early Diagnosis of Acute Appendicitis," C. Rusk McAdam, JtD, Medical Director, Fisher Body St Louis Division, SL Louis, Missouri. AFTERNOON Session: Chairman, F. B. Wzshard, mty, as. Medical Director, Delco-Remy Division, Anderson. Indiana. 15. "Relationship of the Length of the Inguinal Liga ment to the Occurrence of Inguinal Hernia," C. M. Hnxekbrakd, MX)., Medical Director, Harrison Radiator DIvi- sion, Lockport, New York. 16. "Hernia in Industry; Review of the Cases During the Past Ten Years," R. L. Johnston, MX)., Medical Director, Inland Mfg. Division. Dayton. 17. "Antiseptics and Their Action," R. M. Freeman. MJD., Medical Director, Linden Division, Linden, New Jersey. 18. "Management of Fractures of the Spine," R. W. Pobobsky, MD, Medical Director, Electro-Motive Divi sion, La Grange, Illinois. Except for Dr. Sulzberger's address on "Recent Developments in the Occupational Dermatoses" all of the papers given at this Conference are in cluded here in full text, in the order of their places on the Program: Recent Developments in Relation to Silicosis * LeRoy U. Gardner, MJD., Director, The Saranac Laboratory for the Study . of Tuberculosis, Saranac Lake, New York HEN your Chairman asked me to speak of Wnew developments in the field of silicosis I was perplexed because all but a few of the pathological, clinical and diagnostic aspects of this disease are now well established. I realized Page 46 INDUSTRIAL MET TE February, 194U . that you had become better acquainted than I with in the uonchioles. As collagen forms and con the practical problems of diagnosis because you tracts, the air spaces are obliterated by scar tis were dealing with them ever}' day. After some sue. In experimental animals, at least, this change deliberation I decided to tell you of some of the is not a progressive one after cessation of exposure experimental work in progress at the Saranac to the dust as is the case in the response to quartz. Laboratory and to permit myself to speculate as Perhaps the reason is the deposition of the pe to: its significance. These experiments are incom culiar iron-containing coating on the surface of plete and no conclusions are possible now, but the inhaled fibres giving rise to the characteristic perhaps they may ultimately lead to a better un "asbestosis bodies." Dr. Timothy Learv consid derstanding of the action of irritant dusts upon ers3 that the resultant smooth rounded ends of the lungs. these bodies are no longer capable of scratching As far as I have been able to discover, it is still the delicate surfaces of the air spaces. true that only certain forms of free silica and the Finally it is most suggestive that among dozens group of fibrous silicates known as asbestos, are of different silicate minerals only the five known capable of producing fibrosis in a normal lung. as asbestos, which are unique because they are Many other silicates have been incriminated by fibrous in structure, should be commonly recog roentgenologists, but when autopsy specimens nized as pulmonary irritants. The variation in have been examined it is discovered that there chemical composition within this group is greater is associated chronic infection or that the inhaled than that between them and many other silicates. dust contains significant quantities of free silica. In fact chrysotile asbestos has the same chemical I shall first compare the action of chrysotile as formula as a non-fibrous silicate, serpentine, bestos with that of quartz upon experimental ani which is physiologically inert. Obviously irrita mals and review considerable evidence bearing tion would seem to be associated with the physical, on their respective modes of action. A few of rather than the chemical, composition of these these observations now have Dractical significance; minerals. others may prove to be quite unrelated to the One point of practical significance may be indi pneumoconioses found in human beings. cated by these observations, namely, that very finely ground asbestos is not dangerous. This FOR the last year or two we have been coming conclusion has support in clinical observation, for to the conclusion that inhaled asbestos fibres it has long been known that at the Thetford mills are irritating not because they are silicates but bethere was no clinical asbestosis even though in cause they are stiff fibres which mechanically ir former years the atmosphere was very dusty and ritate the lungs. Unlike the free silicas, these the dust was extremely fine. The fact that fabri minerals will not stimulate fibroblasts in any part cation of fibres of the same mineral in American of the body; only those in the lungs are affected. plants could produce disease was one of the puz It was inferred that these organs were affected zling features of this disease. But these experi because the movements of respiration are so much ments offer a plausible explanation. The fine dust more rapid and continuous than those of other in the mills is composed of serpentine and ex viscera. Then it was discovered that if asbestos tremely short chrysotile fibres; that in the spin was ground very finely so that few of the fibres ning and weaving mills contains many more long were longer than in length the irritating prop fibres. erty of the asbestos was practically destroyed. In Ihalation experiments with such fine chrysotile asbestos have now been continued for three years. N THE case of free silica everything points to a chemical form of irritation although the solu No fibrosis has developed in spite of the fact that bility hypothesis as now conceived is not com an average atmospheric concentration of 125 mil patible with all the observations that have been lion particles per cubic foot of air has been main made. In experimental animals inhaling or in tained. In contrast I would point out that in a jected with excessive quantities of pure quartz previously reported experiment* one third this or flint in exceedingly fine state of subdivision, it concentration of long fibre asbestos dust produced can be observed that tissue reaction takes place well marked fibrosis after about two years. in two stages. First there is an acute inflamma If the effect of asbestos were chemical, one tion resulting in necrosis. Following it there is would expect that a decrease in size would ac healing with fibrosis in the form of a granuloma celerate tissue response. With free silica large whose end product is the silicotic nodule. The particles have little effect, but as their size de collagen laid down by the connective tissue cells creases cellular reaction becomes more vigorous is modified in a peculiar way analagous to that in and even constitutional symptoms may ensue.5 the tanning of leather, and this is responsible for With fibrous asbestos the reverse is true. the characteristic hyalinization of silicotic fibro The histology of early asbestosis does not sug sis. Incidentally, leather has been "tanned with gest a chemical injury. Even under the most ex silica and sections of such leather reveal that the treme conditions that can be created by artificial collagen has undergone a similar hyaline trans iiijection there is no preliminary phase of tissue formation. In human subjects only cases of rapid necrosis with infiltration of leucocytes as occurs ly developing silicosis show evidence of a two- with high concentrations of very fine quartz. The stage reaction. In those with ordinary chronic connective tissue cells merely multiply very slow disease, degenerative changes are slight and over ly in areas where the asbestos fibres are caught shadowed by the formation of connective tissue. ry,1940 id concar tis- gc -are quartz, the peface of :teristic considnds of fetching dozens known ley are recog- on m eater licates. temical <entine, irritalysical, fe these ;e indiit verv . This ion, for d. mills ^n \\.j -nd : fabrilerican ie puzjxperi- dust nd ex3 spinre long ints to fe solu- t comI e been I or in quartz sion, it w place ammalere is luloma . The e cells that in fele for fifcro* transrapidj twoironic l overtissue. Vol. 9, No. 2 INDUSTRIAL MEDICI! Page 47 The solubility hypothesis is based solely upon ticles of larger size and it has not been observed indirect evidence. It is known that colloidal silica on injecting suspensions of several other minerals is toxic and that quartz will dissolve to some ex ground to the same particle size. tent in slightly alkaline fluids of the same pH as Symptoms are initiated even before completing those of the body. But it has never been possi the injection by the onset of rapid, labored respir ble to prove that silica has dissolved within the ation. The skin of the face and extremities becomes body, because the soluble material is immediately pale. The animal displays uncoordinated mus combined with local tissue elements. It is now cular movements and sporadic convulsions ter generally accepted that the soluble silica detected minating in death if the dose is sufficient. When in the urine and blood probably comes from in- smaller doses are administered complete recovery gested food and drink rather than from inhaled takes place. . dust. Autopsy of fatal cases discloses an intense en gorgement of the spleen, omentum and subperi- WE have made a good many experiments whose toneal tissues which are deep purple-red in color. results are difficult to reconcile with the solu The liver, and in fact practically all the remainder bility hypothesis. They do not necessarily invaolfi- the body, is almost bloodless. Counts of ear. date it because we may not have all the facts and vein blood show only about half the number of do not know how to interpret them. For example, leucocytes present just before the injection and we have found that cellular reactions begin within IS to 30 minutes after injecting fine particulate silica. In the test-tube traces of dissolved silica are only discoverable by an exceedingly sensitive colorimetric reaction after 12 to 24 hours. Possi bly "vital" factors may accelerate the process, but no means of evaluating them has yet been dis covered. No one has ever produced fibrosis by single or repeated injections of the various forms of soluble silica. The effect is apparently not due a corresponding reduction in red blood cells. The blood no longer clots. There is no hemolysis. Animals that have recovered from one reaction seem to acquire a tolerance so that in some in stances at least twice the former dose may be in jected without symptoms. The degree of toler ance, however, varies widely in different indi viduals. / These symptoms are not influenced by the in jection of adrenalin. They are not reproduced to the quantity of silica dissolved, for many of the by transfusing the blood of an animal dying in inert silicates in vitro are more soluble than quartz shock into another one of the same species. They or flint Evidences of alteration of the surface are only exhibited on injecting suspensions of of quartz particles long in contact with living tis sue have thus far escaped detection. In years of experimenting to discover the mechanisms by which free silica exerts its pe culiar effects upon living tissues we have re- quartz particles less than 3p. in diameter. They are not produced by injecting the supernatant salt solution from which the quartz particles have been removed by centrifugation. The severity of the reaction does not vary with the age of the par . peatedly observed evidences of a specific toxicity. ticle suspension, although the amount of soluble Guinea pigs, injected intraperitoneally with large silica increases on standing. doses of fine quartz particles are often obviously The toxic effects of quartz can be more or less sick for some hours. When Mr. Cummings and effectively neutralized by adding small amounts Mr.- Redlin3 were seeking an avenue for the of different substances. Colloidal aluminum hy quantitative introduction of silica they tried in* travenous injections into rabbits and discovered the method which we now use as a standard for comparing reactions to different dusts. But in droxide gives complete protection in a dilution of 0.03**; colloidal ferric hydroxide is much less effective. Animal charcoal cannot be injected, be cause it flocculates with the quartz and produces cidentally they found that these animals would emboli. The finely ground metallic aluminum, die very promptly if the unit dose of quartz par used by Denny, Robson and Irwin4 in the preven ticles were too large. These deaths were not em tion of silicosis has no influence upon acute in bolic because they did not occur with large par toxication. Further experiments are in progress ticles but only when the quartz grains were 3/i or to verify the conclusion of these authors that less in diameter, and they did not develop on in aluminum coats the surface of the quartz particles jecting suspensions of other minerals ground to with insoluble material.* the same size. Recent observations indicate that all species of Mr. Dworski and Mr. Delahant have extended animals are not equally susceptible to intravenous these early observations in a long series of ex injections of quartz. Dogs, which develop sili periments that have yielded interesting though cotic fibrosis very slowly and under conditions puzzling information. They have shown that fine not yet denned, tolerate intravenous injections of silica injected into the left side of a guinea pig's comparatively large doses of fine quartz without heart acts like a strong poison. symptoms of any kind. Rabbits, guinea pigs and Symptoms of shock followed by death within white rats all die of shock. a few minutes to one hour occur when a 400-gram Soluble colloidal silica in dispersed phase is also guinea pig receives an intracardiac injection of 3 0r 4 cc.:of a 1% suspension of 1 to 3^ quartz par ades in physiological salt solution. The reaction 15 specific in that it is not produced by quartz par Subsequent experiments have shown that sterilizing suspensions of metallic aluminum by heat destroys their power of neutralizing the action of silica. Unheated sus pensions of the metal are just as effective as the hydroxide. Page 48 ... INDUSTRIAL MEDIC r % February, 194q '; toxic, and intravenous injections produce the re peared to be quite uninfluenced by the ingested actions just described with extremely small doses. material. In the case of particles 3ft or under the With larger ones death occurs promptly with number inside each phagocyte was countless, and symptoms referable to the respiratory tract The there was marked evidence of degeneration of the lesions are then confined to over-distention of cytoplasm of these cells. In other words, the ef the lungs and subpleural petechial hemorrhages. fect of surface area had to be exerted inside of the cell and not upon the body fluids as a whole. Ex THE results produced by injecting particulate tracellular quartz seemed to have little influence, silica into the circulation all suggest a rela and even intracellular particles of a large size tionship to a large amount of mineral surface sudproduced no visible evidence of irritation. j denly brought into contact with the blood or tis sues. This is borne out both by the absence of reaction to large particles in excess of 3> in diam eter and possibly by the observations on neutral ization. Any effect due to preformed soluble silica liberated in the suspension before injection has been eliminated, and no active soluble silica could be demonstrated in the blood of an animal dying in shock by transfusion into a second host. Everything now suggests an effect taking place THIS observation brings us back to the cause:*. of these progressive changes. Apparently they are initiated with degeneration in the pri-: mary phagocytes, an effect which is exactly paral-" leled -in the histogenesis of tuberculosis. Some; years ago I published a paper calling attention: to the similarities between silicosis and tuber culosis.5 In both of these diseases the primary irritants, quartz grains or tubercule bacilli, as' very rapidly at the interface between the quartz the case may be, intoxicate the phagocytes.' la5 and some element in the blood or tissues. Whe tuberculosis the cells thus poisoned are commonly^ ther this is due to the very rapid production of designated as "epithelioid cells;" in silicosis the colloidal silica in this location or to unique elec morphological effect is similar. Visible fat. trical properties of quartz is still a fascinating droplets accumulate in the cytoplasm and the subject for speculation. In the same category is elements stainable by supravital dyes undergo the demonstration of the tolerance conferred by rearrangements in characteristic patterns. Giant previous injections. cells of the Langhan's type are produced in each- The manifestation of acute toxic symptoms by disease by stimulation and repeated multiplication- i those species of animals which develop silicotic of the nucleus. In each disease many cells die. fibrosis most readily and their absence in the dog, and their degenerated products are liberated inf which appears to be much more resistant, sug the tissue spaces. Incidentally it is the pabulum gests that these immediate reactions may have of necrotic cells in silicotic lesions on which tu some bearing on the etiology of silicosis. Until bercle thrive so well, an effect which is responsible more is learned about the reactions in the dog no for the high frequency' of complicating tuber inference is possible. culous infection in silicotics. In the tubercle it The influence of particle size is just as signifi is in the necrotic or caseous tissue that tubercle cant in the production of advanced silicotic fibro bacilli are most frequent. Perhaps they not only sis as it is in eliciting acute symptoms of intoxica cause such caseation but they themselves thrive tion.. Many injection experiments have convinced on it. Coincidentally more cells migrate to the us that quartz particles over 3p in diameter are area and proliferate to form the granulomatous of little or no physiological significance. The fact nodule that is characteristic of each disease. * that the lungs of persons exposed to most dusts Finally the production of necrotic tissue, high contain few particles larger than 10/i in diameter in lipoids, by two very dissimilar primary irri has been responsible for the establishment of this tants recalls the experiments of Fallon* and his size as the maximum important in dust counting. hypothesis that it is these lipoids which are dH As a matter of fact we know that with some dusts rectly responsible for the formation of the granu-T there may be many larger ones. While it would loma. He showed that the injection of such be just as well that any large fragments should lipoids, freed at least partially of contaminating be excluded from the lungs, it is felt that only silica particles, was capable of producing a granu-; ones 3/t or less in diameter are responsible for lomatous nodule. | causing silicotic fibrosis. Such mechanisms may be involved in the pro We have long maintained that particles of this duction of both silicotic nodules and tubercles. size are irritating because they present a suffi It still remains to demonstrate the nature of the cient surface of silica to the fluids. Recently Mr. primary injury by each of these irritants, and it- Dworski decided to test this reasoning further by is this problem that will probably engage our at injecting graded doses of different sized quartz tention for some time to come. particles which would all present the same total surface area. He found, however, that regardless Bibliography: of the total surface, silicotic reaction only de 1. Gardner. L. U.. and Ccmmencs. D.E.,: Studies on veloped when the size of the particles was 3n or Experimental Pneumoconiosis: VI. Inhalation of Asbestos less. On examining his material it was-discov ered that with particles 4 to 5/t in diameter or larger there were only two to four visible in a thin section of each phagocyte. These cells ap Dust: Its Effect upon Primary Tuberculous Infection. / lndust. Hyp., 13:65-63 and 97-114. February and March1931. 2. Gardner, L. U., and Cummings, D. E.: The Reaction to Fine and Medium-Sized Quartz and Aluminum Oxid* . VOL. 9. No. 2 INDUSTRIAL MEDICINE ( Page 49 Pirtlclcs. Silicotic Cirrhosis of the Liver. Am. J. Path., tion. This is done with the intent of placing that 1933:9, Supplement whole number 54, 751-763. individual in industry where he or she is best 3. Timothy Leary: Personal Communication. physically as well as mentally fitted. This exam 4. Denny. J. J-. Robson. W. D., and Irwin. D. A.: The Prevention of Silicosis by Metallic Aluminum, Canad. M. A. J* 37:1-11, 1937. ination is not done for the purpose of either pass ing or rejecting that person for employment. This 5. Gardner. L. U.: The Similarity of the Lesions Pro pre-employment examination gives the examining duced by Silica and the Tubercle Bacillus. Am. J. Path^ physician the best possible opportunity to detect 13:13-23, January, 1937. pulmonary tuberculosis. 6. Fallon. J. T.: Specific Tissue Reaction to Phos Dr. Robinson Bosworth, President of the Illinois' pholipids: A Suggested Explanation for the Similarity of the Lesions of Silicosis and Pulmonary Tuberculosis. Tuberculosis Association, states:3 "85% of adult A Canad. M. A. J, 36:223-228, 1937. pulmonary tuberculosis has its beginning in the age group 18 to 28. In the vast majority of cases there are no symptoms and no physical signs." A Plan for the Control of It is exactly this age group that concerns us most in our pre-employment physical examina Tuberculosis in Industry tion, for it is during this age period that most em ployees first enter industry. We therefore feel Max R. Burnell, MJ), that such an examination is not complete without an x-ray of the chest Medical Director, We believe, with Dr. Andrew R. Riddell, of the AC Spark Plug Division, General Motors Corp., Industrial Hygiene Department, Ontario Depart Flint, Michigan ment of Health, that the wholesale tuberculin testing in industry has many disadvantages. He T IS a proud day when it can be stated that I one o the safest places to be in this country is at work. Statistics from the National Safety states that3 "the individuals must present them selves at least three times--there is considerable disruption of work--even after most careful ex Council seem to ibear this out The reduction inplanation as to the meaning of the test, the em the frequency and severity accident rates in our ployees who react positively are greatly dis industrial institutions has been nothing short of turbed." remarkable. Prevention has been the watchword. Applicants in whom active pulmonary tuber A With such improvements, the consideration of culosis is discovered are sent to their family physi * je medical departments in industry has more re cian. Our roentgenogram is at his disposal, but cently been drawn to the general health of its em must be returned to our files so that we can later ployees. Attention to the control of tuberculosis compare the progress of the disease and determine has been a very major issue. We believe that in at what future time those persons may be pro no adult group throughout the country can so nounced employable. much be accomplished in prevention and early Applicants with arrested or quiescent tubercu 0 recognition of this disease as in our industrial in losis are placed at work after being informed of stitutions. their condition and instructed to return for pe Legislation varies in the different States regard riodic examinations. These examinations for new ing occupational disease but the ultimate objective employees, in this classification, are conducted of this legislation is dear: The general health of every three months. the employee must increasingly become the re- It has been increasingly evident that our re sponsibility of the employer. While the status of sponsibility does not end there. We explain to * tuberculosis has been debated by many legisla the employee that while he now has an arrested tive bodies, silico-tuberculosis is definitely com tuberculosis, it was once active. We encourage pensable. In the state of Illinois the new occupa him to have the members of his family examined tional disease disability compensation law went by the family physician. We feel that not until into effect on October 1, 1936. Dr. C. 0. Sapping- then has industry wholly discharged its duty to ton states that "during the first year of the oper- 'the community. q ation of this law, 10.9 % of disability claims filed 2. Periodic Examinations for Old Employees. were for pulmonary tuberculosis while silicosis These examinations are made at different times daims were 15% of the totaL"1 and for varied reasons: The corporation that is looking toward the fu (a) Upon returning to work after vacations. ture with the best interests of its employees in mind certainly should be actively engaged in the (b) After absence caused by an illness. (c) Re-employment following seasonal lay-off. problem of the control of tuberculosis. Many of our industrial institutions have already shown, by (d) Transfer from one type of work to another. (e) Medical department requesting the exam marked reduction of the incidence of pulmonary ination for some definite reason. berculosis, just how this can be accomplished. (f) Volunteer requests by the employee for Our own corporation has a very definite program such_an examination. concerning tuberculosis. Little comment is necessary concerning these examinations except to state that every employee q npHE PROGRAM: 1. The Pre - Employment comes into our medical department for a general X Physical Examination. Every prospective physical check up at least once each year. employee is given a thorough physical examina Two types of periodic examinations deserve Page SO INDUSTRIAL MEDICINI February, 19-KT " special attention. First, the medical department requesting the employee to appear for some spe cific reason. Each employee has his own physical record Card. His visits to the medical department are recorded here. If it is noticed that frequent visits are being made for colds, bronchitis, loss of weight, feelings of fatigue, etc., he is requested to appear so that we may get at the underlying cause. These examinations are always accom panied by x-rays of the chest and if the disability is from early tuberculosis, we are able to detect it. The other type of periodic examination is most gratifying to the medical man in industry -- the physical' check up requested by the employee him self. This is, indeed, a measure of the confidence that has been established between the medical de- partment and the worker. Cooperation with the family physician is of paramount importance. When some disability is uncovered and it is discussed with the employee's own physician, that employee realizes that the corporation is not attempting to deprive him of his job but is trying to keep him at work by im proving his health. Again confidence is estab lished, and that is the best foundation for a suc cessful program to maintain a high standard of health within your organization. One striking example of such a relationship is of unusual interest in regard to the .tuberculosis problem. After the installation of excellent x-ray equipment in one of our plant hospitals, it was suggested to the employees that they take advan tage of [this opportunity to have their chests x-rayed. | These were all old employees, some with service records of over 20 years. The re sponse was amazing. Over 4600 employees re quested | the examination during the first 10 months. ' All of these employees were working every day. They considered themselves in excellent health-- so did the medical department as a matter of fact, as their 'previous physical examinations during the year had shown no disabilities. However, 12 cases of early active tuberculosis and 42 cases of arrested or quiescent tuberculosis were brought to light. I The active cases are all under treatment --nine of them have been referred to sanatoria by the family physician. Active tuberculosis has also been found by the family physician in the house' holds of those in the arrested groups. 3. Control of Tuberculosis Within the Plant. If there is to be real control of tuberculosis in in dustry, the activities of the industrial medical de partments must not stop with examinations with in the plant hospital. Dr. G. !T. Drolet4 has shown conclusively that where there are bona fide cases of active tubercu losis the results of treatment, irrespective of where or. how, are still far from satisfactory. In other words, "the hopeful sign is steady reduction in the mimber of cases and not what happens IP those who actually develop the disease. Progress has come by prevention and not through treat ment."5 ; We must take a page from the program of the plant safety engineer and `again adopt "preven tion" as our slogan. As Dr. C. D. Selby has stated, the industrial physician is the health officer of the plant.* "It i* his duty to locate, identify jmd determine the un- portance of all occupational and environmental sources of disease or health impairment and to see that they are corrected.'* __ | In relationship to tuberculosis he must know if' "exposures" to the inhalation of dust particles at. obnoxious gases and vapors are present within the- ; plant Also he must pay attention to overcrowds j ing, proper lighting, ventilation, arranging rest; \ periods for those engaged in strenuous or neces sarily rapid operations, and have knowledge of thd toxicity of materials handled. Dr. Hamilton7 has listed definite industrial po sons which are capable of irritating severely th^E bronchopulmonary system and activating a pre-^ t existing pulmonary tuberculosis -- chlorine gas/ \ ammonia, benzine, brass fumes, phosgene, nitric-. J. acid fumes, selenium and vanadium, to mention z: few. .Sj The danger of exposure to the inhalation of; t dust, especially silica dioxide (crystalline silica)] f is only too well known. It is not within the prov-; e ince of this paper to discuss silicosis. However^; \ as Dr. Riddell5 has stated. "Tuberculosis is the; \ commonest and most important complication in: i. deaths among silicotics. Therefore in any dis-: [ cussion of the control of tuberculosis in industry;! the subject of silico-tuberculosis must have its! : place." . i Dr. LeRoy Gardner* contends that "silicosis is the menace that it is because it specifically pre disposes to tuberculosis. It is the latter which is responsible for disability, lost time, and, in many cases, death, and it is really tuberculosis against; which we have to fight." H\ This statement has been recently challenged bv : Dr. George Ornstein.1'* ^ Whatever the conclusions may be in the future- concerning the exact relationship of silicosis to tuberculosis, the industrial physician must con tinue his attempt to eliminate dust. Dust counts should be made to locate the points of greatest hazard. Consultations should be held' with the safety engineer as to the best type of con trol, whether (a) mechanical ventilation of the positive or supply type or local exhaust systems: (b) isolation or total enclosure methods, or (c) respiratory protection by respirators and positive pressure masks or helmets, are to be advised. THE purpose of industry is manufacturing-' i Often the installation of adequate equipment ; is expensive. This adds to the cost of the-m'anu- factured article. It behooves the industrial physi- f cian to study his problem with care. Our experi- ' ence has proved that when management is in- \ formed of the hazards that are present and shown the necessary steps toward their elimination. | whole-hearted cooperation is immediately forth- t coming. f To Summarize: A plan to control tuberculosis s j 1940 ven- : imntal d to #Pir the pre gas, litric ion a n of ilica) . provever, s the m in 'i -i sis is preich is #nany gainst ed by 'uture ^is to . conpoints I held ' tfconof the ^terns; )r (c) Dsitive .d. culosis Vol. 9, No. - INDUSTRIAL MEDIC*. Page 51 in industry must start with pre-employment ex ail know, from the several years that industry has amination." The majority of employees firs: er.ter recognized its use. The contact of the roentgen industry during the age period when adul: pul ologist with the industrial physician has been monary tuberculosis is most prevalent. X-ray of largely in the field of forensic medicine. With the chest is a requirement, if early cases are :o be the new awakening of industry to the importance detected. When arrested or quiescent casss arc of preventive medicine has come a change in the discovered, we feel that it is industry's duty :o the qualifications of the roentgenologist and the physi community to cooperate with the family physician cian. and a necessity for greater cooperation with in an attempt to uncover active cases in that em and by the management of the organization. This ployee's household. has meant a study of the hazards of industry. That . Once the employee is at work, periodic ex necessitates not only an intimate knowledge of aminations are the next requirement. Such those hazards but of those who may encounter an examination should be conducted at least them. Therefore, the roentgenologist must have a annually. The employee quickly learns the per close contact with the factory physician, who in sonal value of these physical check ups. Con turn, must have contact with the individual em fidence then established between the worker and ployee and be conversant with the nature of his the medical department goes far toward simplify work. ing any plan for the control of tuberculosis in in Just how large a part the- roentgenologist can dustry. contribute to this field of medicine depends upon Lastly, the influence of the industrial medical two factors: first, the physical set-up of the de department must extend to every department of partment and, second, the cooperation received the operating plant. Inspections must be made from the management. regularly. The industrial physician should be The extent of the equipment naturally depends familiar with every possible "exposure" to health upon the size of the plant and the burden that will impairment. This is the final requirement of our be imposed upon the medical department. How program. ever, there are certain minimum requirements Our goal should be to make the employee's that can not be neglected if efficient service is to hours at work not only the safest from accident be rendered. The equipment and arrangement of but also the freest from exposure to disease. the department must be such as will produce the References: 1. C O. Sappincton, MJD., DhJ*H.: Central States So ciety of Industrial Medicine and Surgery. May 17. 1933. 2. Robinson Bosworth, M.D.: University of Michigan Postgraduate Lecture, October. 1938. results most economically. In the past two years the author has had the opportunity to organize and try out, what in his own mind is a model industrial x-ray department, this because of a sympathetic management and 3. Andrew R. Riddell, M.D.: Industrial Medicine, Vol. 6. No. 5. May, 1939. 4. G. T. Drolet, MJ5.: Am. Rev. Tuberc- Feb- 1933. 5. James A. Britton, M.D.: Industrial Medicine, Vol. 7.No. 6. June, 1938. the helpful cooperation of a medical department which was attuned to the requirements of modem industrial medicine. It is impossible to do adequate work without 6. C. D. Selby, MJJ.: Paper presented before National efficient equipment. And it has been thoroughly Tuberculosis Association, Los Angeles, June 23. 1938. 7. Alice Hamilton. MJD.: Industrial Poisons in the United' States. MacMillan Co. ' 8. Andrew R. Riddell, MJD.: Trans. National Tuber culosis Association, 29-1933. demonstrated that in larger factories x-ray work can be done most economically within the plant itself. To refer cases to the private roentgenolo gist is both expensive and lacks the cohesive ef 9. LeRoy U. Gardner, M.D.: Third Symposium on Silicosis, 1937. 10. George Ornstein, MJ).: Industrial Medicine, VoL ' 7, No. 7. July, 1938. ficiency that can only be obtained within the organization. The result of two years' experience has demon strated that the initial cost of the x-ray equipment is an extremely small factor in the economics of a X-Ray in Industry medical department. With the most modem equipment and with a well regulated plan of M. William Clift, M.D., F.A.C.P.. Hurley Hospital. Flint, Michigan operation the cost per case is hardly an incident in factory medicine. My experience in the or ganization with which I am connected has shown that the entire capital investment for the x-ray HE new attitude that has grown up between equipment has not only been liquidated but has Tindustrial physicians and the employees of also shown a dividend in less than two years. How this organization, stimulated by the consult ever. the greatest dividend has been in the salvage ant, has made it not only an interesting privilegoef individuals working in factories and by appreci but also a pleasure for an associate to be in contact ating their physical needs, placing them back in with What we must feel are among the best ideals industry in positions they can adequately fulfill. of the medical profession. Therefore, it seems to In the time that we have had the opportunity to me that you might be interested in my experience examine the employees, we have seen upwards of of the past two vears in the field of x-rav in in 6000 cases. We have detected cases of early tu dustry. berculosis. placed them under the proper condi That x-ray has had its definite function you tions for their rehabilitation, and had the pleasure