Document gbk7Jjvo95w57ZVOkpM5pKVZa
The a American / Ceramic ' Society , s
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
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(U CERAMIC ABSTRACTS
IMS
' Compiled by
The American Ceramic Society
Volume 19, 1940
Ross C. Pour, Editor
Muir J. Gas
Emily C. Vast Soto ice Dorothy J. Wallace
J Auutantt
Committee on Publication}: J. D. Sollitak, Chairman, E. E. MajuakER, T. B. AntB, A. N. Pisx, R. C Pour
ABSTRACTERS
J n. Aunia
L M. Church
A. A. A^an
V. M. Cohn
L. R. Barrett M, V. Coodoida
K. V. tv. Bartlett P. S. Dear
A. C. Bvn
Frank Filber
D. A. Biddlt
S'. D. Pnttr
A. Biddulph
J. L. Callup
V. I.. ioum }, D. Gat '
S'. H. Bruckner ft. A. Cmory
P. I* Budnikov Robert Hall*
J- C. Chaiton Has Mannheim
J. J. Hatel F. 0. Hack R. A. Htiodl P. 0- Harold M. B. m C. M. Hutt J. r. Hyde Htrbaat tiwlev C- B lentil B. Z. Kaioich B. E, Kiokulkio
S`, D. Klucmaa Seiji Kendo Yomo Korn RB.obBa. nLaKnueoio TV. Loaweothal F. S Slallatte V. 5. da March!
I.. F. Mae
E. H. McClelland
J. . Soy
f. G. Phtttipa E. C. Flarea Alaaia Piocua M. E. Poor KHa. tKb.trRioiochRaerdaidon R. A. Rooaebacl: B. C. Rupracht A. B. Haul, I, P. Shanolc LuctUc Sbattuck
G. R. Shelton K. E. Simpaoe A. P. Som
P. E. Soonanachtin A. G. Stare
B. K. Sirom M. Takai I~ E. Tbieaa Han, Tburoaucr K, J Vachuaka F. J. tvuui
Editorial Office: 2523 North Rich Street, Columbus. Ohio Publication Office: 2Uih and Northampton Streets. Easton. Pa.
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1940
Central
79
9 General
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Ceramic Laboratories: Georgia School of Technology.
Handling and disposing of recovered fly ash and dust
Anon. Ceram. Ate. 34 [11 12 [1939). Massachusetts In J. T. Dkvtsch. Com&uNien, 11 [51 22-24 (1939).--Three
t
stitute of Technology. Ibid.. |2| 44. New York Swte methods are reviewed, including the vacuum, the sump, College of Ceramics. Hid.. p, 45. Rutgers University. and the introduction of the dust by means of a water-
l
Ibid.. (3J 78. University of Illinois. Ibid.. [1| 13.--The cooled ram into a slagging-bottom furnace near the level
Uboratories are briefly described and illustrated. F.G.H.
of the molten slag. The last method is discussed in detail.
Ceramic schools. Current surrey of status and prog
H .Ej.
ress. Anon. Ceram. At*. 33 (6j 171-91 (1939).--A
Health damage by means of industrial dust. Otto
comprehensive survey of ceramic schools throughout the Schultz. Casmaske. 11, 57-66 (1939 (.--Pure coal dust
country is given. The course of instruction, the teaching is not dangerous; neither is silicon carbide nor corundum
staff, the research staff, and the student body of each dust. Tin, copper, bronze, and aluminum dust make slight
of the following schools are described: Georgia School alterations in the lungs, and iron oxide makes stronger
of Technology, University of Illinois, Massachusetts Insti alterations, but none of these dusts affects the health.
tute of Technology. Missouri School of Mines. New York
State College of Ceramics, North Carolina State College, University of North Dakota, Ohio State University,
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 dust causes
Pennsylvania Sate College, Rutgers University. Virginia
Polytechnic Institute. University of Washington. Univer*
sity of Oklahoma, West Virginia University, and Carnegie
Institute of Technology. Illustrated.
F.GJi.
Contact law lor engineers. L. T. Puns. ComSus-
/wit, 11 [2] 33-34 (1939).--F. explains implied sad ex.
pressed contracts, as interpreted by the higher courts,
with particular reference to the employment of engineers
and personal services rendered fay 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-speed 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-synchroairing drives may be used to keep
a kiln and the kiln feeder in synchronism. W.D.F.
Development of central-heating systems. Lrtrci Ranh.
Cmndh.-Ing.. 60 (50 j 753 (1937).--R. describes the de
velopment of modern central-heating systems. A new
type of installation is explained, and various examples are
calculated.
'
W.DJL -
Effect of condensate extraction on efficiency of the heat
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 latest 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 aod has a high fatality. Fyro-
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 is the lungs. Methods of prevention ^arc dis
cussed generally.
T.DJ,
Healthy air, a guide 'for plant superintendents and
workmen. Otto Elsnex. 0*sundk.~It., 60 (441 676
(1937).--A review issued by the German Society for 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 msy be avoided. Anon. Gtsundk.-
In60 [521795 (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 prewarmed air. Benzol vapors are
heavier than air and. for this reason, sink to the floor.
cycle. W. M. Metis*. Combustion. 11 [2( 30-32 (1939).-- When installing a new air-ventilating system; therefore,
31. contends that the value of high superheat as a means suction openings should be located in the floor or near it.
of improving the efficiency of steam power plants is being Pieces treated with 1 benzol-containing solution should
Overestimated and recommends the use of high initial steam be dried in a well ventilating drier cupboard or special
pressures at moderate initial superheat combined with drying rooms. Benxol-coaiainiag vessels must be kept
the mechanical extraction of condensate at appropriate covered.
W.D.K.
stages of the expansion. '
H.E.5.
Improved system In the application of noncondensiag or
y Fatalities from silicosis and asbestos!*; their incidence extraction turbines. H. W. Caoss and E. S. Wells. J*.
in industry. Anon. Iron d* Coal Trades Res., 139 [37321 Combustion, 11 [1J 32-35 (1939).--Since electrical output
336 (1939).--The annual report of the Chief Inspector is definitely established by the energy drop between initial
of Factories shows that from 1935 to 1933 inclusive, deaths and exhaust conditions and by the quantity of steam flow,
from the two lung diseases in the refractories industries increasing the total steam pressure at the throttle for a
and in the manufacture of pottery have been approximately given pressure increases the available energy and conse
Constant, i.e.. G3 in 1935, 56 in 1936, 83 in 1937, and 60 quently the electrical output.' The application of a com
in 1938. Sandstone quarrying and dressing took 40 lives bined desuperheater and feed-water heater at the ex
in 1935.43 in 1936, 19 in 1957, and 27 in 1938. Preventive haust is advantageous in realizing gains from the Use of
measures have aided in a generally small decrease: some higher temperature steam. Examples demonstrating the
of these measures are as follows: (1) use of alumina Cor possibilities inherent in such systems are illustrated and
flint in china bedding, (2) use of alumina for siliceous ma explained.
H.E.S.
terial in parting powders. (3) use of nonsiliceous abrasives Lighting for special industrial purpose*. W. R.
for sand or flint in blasting. (4) use of nonsiliceous material Stevens. Traits. Ilium. Eng. Soc. [London], 3 [1] 3-16
for kieselgubr in the slow cooling of steel, and (5) use of (1938).--S, describes installations requiring special lamp
nonsiliceous material for silica brick for lining steel and fittings for explosive and moisture-ridden atmospheres and
other furnaces. See "China--," Ceram. Abs., 18 (fff 54 the use of special sources of fight, such as carbon dioxide
(1939).
M.K.
discharge, daylight tubes, special daylight tungsten fila
Gas beating installation. H. Dietrich. GttundU.-Ing., ments. and high-voltage fluorescent tubes, for color match
60 [45] G< 1 (1937).--D. surveys the developments of gas ing surfaces and special inspections.
HJw.R
heating after the World War and discusses the gas single Living and working conditions in the tristate mining
heating system, the gas central-heating system, special district. Evan Just. Mining Congr. Jour,. 25 [11] 44--,5
gas tanks, tasks with built-in'burners, rentability and gas prices, and the experimental capacity of a boiler on a low
pressure steam-heating system and on a warm water heat ing system. Results of conducted experiments are stated.
(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 wmdy days dust is blown from a
W.DJC.
few flat accumulations of sand. Road dust, however, ac-
1040
General
SI
tests water hardness has beta developed by the German
Society for Chemical Apparatus.
W.D.K.
Surface heat losses from outside luresce walls: J. G.
Coutant. Heat Treating & Porting. 2$ l#| 463 (1939).--
Aluminum paint reduces beat loss from furnace walls.
See Ceram. Abs.. 19 [1J 16 (1940).
S.S.
BOOKS A.V0 SCPaKATE YVEUCATION*
A-S.T.J1- Standards, 1939. . Amateur Society rox
Testing Matexiau. Philadelphia, Pa. Price to non
members SS.OO one part. 913.00 two parts; $23.00 three
parts.--The boot: is in three parts: L Metals: Ferrous and aooferrous metals are discussed; methods of chemical
analysts are not riven. General testing methods are pre sented. H. NomnetaUic material*--eoastrucdonaL This
part includes cementitious materials, concrete and aggre gates. masonry building units, ceramics, refractories, pyro and tile, thermal insulating materials, timber preserva
tives. paints, varnishes, and lacquers, road materials, waterproofing and roofing materials, and soils. General
testing methods and thermometers are described. HI, Non metallie materials--general. Fuels, petroleum products,
electrical insulating materials, rubber textiles, soaps and . detergents, paper, plastics, and water are covered. Gen
eral testing methods are given. Available from Amer.
Soe- Testing Materials. 260 6. Broad St., Philadelphia, Pa, F.F.
Finding List for United States Patent, Design, Trade
Mark, Reissue, Label, Print, and Plant Patent Numbers. M. Ra-voau. and E. B. Watson. University of Cali
fornia Press. Berkeley. 1938. 31pp. Price 35d- Reviewed
in ifeeh. Eng.. 01 (01 403 (1939).
F.G.H.
Report of the Department of Scientific and Industrial
Research, 1937-1933. H. M. Stationery Office, London. Price3t. Reviewed in Patter? <5* Glass Record, 21 (4JS9-90
(1939).--Methods have been developed for assessing
- weathering characteristics of day products fired under various conditions. Work on day roofing tile has been
continued. Investigations on refractory materials indude (1) the pressing process and its. relation to the texture of
clay, silica, and sfilimanite brick; (2) the drying of elayware; and (3) the firing operation. A careful study of
the smoke emission from various intermittent kilns firing blue and brindled heavy day products has been made, and suggestions are advanced far its reduction and con
trol. Laboratory work aiming at relating the conditions of atmosphere and temperature with the color of blue
firing days has also been undertaken and has progressed satisfactorily.
Drying cracks are due to differences in moisture con tent established in different parts of the day body, espe cially between the surface and the interior. Differential shrinkage thus occurs as drying proceeds, and stresses are produced. The direct method of studying the problem consists in determining the fastest rate at which particular shapes of a given day can be dried with safety, and the variation of that rate with such factors as the temperature
and the size and shape of the body. There is an optimum
temperature at which drying is most readily carried out;
the smooth nature of the relationships between greatest
safe rate of drying and the dimensions of the test pieces
suggests that aa ultimate understanding of the phenome
non of cracking will be achieved.
-
A theory of the mechanism of the flow of water through
plastic day during drying 1ms been developed, in which the
force causing the flow is regarded as a repulsion between
the day panicles which are separated in all directions by
water film*. A measure of this repulsion is obtained from
the moisture content* assumed by the clay when various
pressures are applied through porous pistons into which
the water is allowed to escape. This pressure is an ex
ponential function of the moisture content as b also the
"aqueous conductivity" or the rate of flow of water through
unit volume of the day under unit pressure. On this basis
the distribution of moisture content at any time through
out a drying shape can be theoretically calculated, the
analysb being analogous to that of heat diffusion. A
strict solution is cot possible, but experiments on a num
ber of days show a means of approximation which permits
the calculation of moisture-content distribution in bars
drying from one end only. The experimental verification
of the theoretical results confirms the hypothesis.
Many years' study of electrical insulation and the ma
terials used therefor has greatly improved the reliability
and the advantageous selection, preparation, and use of
insulating materials. Better insulators have been de
veloped, thus reducing the size and eventually the cost of
electrical apparatus of all kinds without loss of quality.
The suitability of certain glasses for use in the manufac
ture of tdepbone insulators b Shown, The degree of
homogeneity in optical glass b almost completely de
termined by the temperature conditions prevailing during
the annealing process. An investigation has been made of
the maximum temperature gradients in an annealing oven
consonant with the production of substantially homogene
ous optical glass. The cooling schedules of the annealing process were experimented with to determine the minimum
period of annealing for glass of high optical quality.
Methods of producing light etch marks on glass have
been developed, and an optical system to enable the degree
of polish of a glass surface to be assessed has been devised.
The preparation of filing materials for etched.lines, required
to be unaffected under specified conditions, is described.
A.B.S.
Silicosis and Asbestosb. Edited by A. J. Lanza.
Oxford University Frees, New York, 1933. 439 pp.
Price $4.35. Reviewed in .Week. Eng.. 61 (5] 405 (1939).--
The medical and public-health aspects of these industrial
dust diseases are comprehensively presented in this book,
to which several physicians have contributed. Tbe history
cf the diseases, their symptoms and diagnosb, their
pathology, and their prevalence in various occupations are
discussed, as -well -as -methods of prevention and control
Each section has a bibliography.
F.G.H.
V
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No. 6
alyscs l from l -with l indi te raw Many * lines tap of is isID. ugicii
R. O.
V. E. 3433.
.iecstraod-
t-H.
Tf.
ree.-- us[aite ore -te ore white 11 tall* sr ores UH. WAU, 9.--Is ate of ate to up to it it is b add. larger which above, iimes-
ume of lint) is an ta ng and r rates :han is ic rive B.S.
1940 Chemistry and Physics--General
149
composition and properties o( the solid and liquid phases,
and the css phase.
_ P-B. & E.S.
Prevention and treadteat of lead poisoning. Imre
Heller. Orrtni Httilap, S3,639--(1 {19391; Client- Alt.,
jj, 8329 (1939).--In Huncarisn Pb works, Pb poisoning
occurs in 10t) to 200 of KJ/.rki laborers annually. Lead ac
cumulated within the human organism can be mobilised
by modifying the Ca/P balance cautiously. This was done
in" clinical experiments by a diet poor in Ca end 3 to 10 gm.
Na phosphate (Wen 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 acid gels: DC. Charles B. Hurd and Haems
tl\ PaTon. Jaur, Pkys. Clem., 44 37-4*2 (1940).--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 PartV see Ceram. Alt., 15 (31 103 (1933).
R.A.G.
Theory of light scattering. S. Paxthasaratmy. Phil.
Hat- 29 (193| US-53 (I94U).--P. shows that the scatter
ing of light observed by Krishsan in binary liquid mixtures
("Molecular. , Ceram. Ait., 17 (3j 119 (1933)) is purely
molecular, while no scattering arises from clusters, il any.
at the critical solution temperature. So new theories as,
.g,, those of Frenkel. Gans. or Muller, appear to be neces
sary to explain Kriabnan's results.
' R.H.
loos
Science Front, 1959. F. Sherwood TavlOr. Cassell
i: Co., Ltd.. London. Price 7s 6d. Reviewed in rimer
Lit. Supp.. 39 (1984( ~9 (1940).--T. describes recent
developments in science, including theoretical researches
and technical inventions. Illustrated.
K.W. W.B.
fatest*
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 (lazes and method of producing. Carl
OberlAnbEr and F. H. Zsaucacx (Slow G.m.b.H.).
f. S. 2.194,246. March 19, 1940 (May 20, 1936).--A
preparation for improving enamels, (lazes, etc., comprises
a magnesium borosilteate 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
20%.
Magnesium titanates and method of making. J. A.
Plunkett and Eugene Waxner (Titanium Alloy Mlg.
Co.). L\ S. 2.196.325, April 9. 1940 (March. 5, 1938).
--A calcined synthetic magnesia-titanic composition con
taining chiefly finely divided magnesium uianate 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 Adamou
(Perosa Carp.). I'. S. 2.19(5,048, April 2.1940 (March 20.
19371.--A process for the production of beryllium oxide
from minerals containing beryllium and tor the cyclic re
covery of the reacting agent employed consists in powder
ing the beryllium-bearing ore,'mixing the powder with an
alkali bifiuoride in an amount corresponding to 2 tools, of
bifiuoride for every BcO molecule present in the ore. add
ing water to form a paste, compressing the paste to
briquettes, beating the briquettes to a temperature be
tween 550* and 300'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
beiyllmm 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 oeutral alkali fluoride to the corresponding acid
fluoride.
Pure titanium dioxide. W. W. Plcchxer and A. W.
Hixson (National Lead Co.). Can. 336.985. Feb. 20.194V
(Oct. 12. 1937).
G.M.H.
Pure titanium oxide. W. W. Plichker and A. W*.
Hixson (National Lead Co.). Can. 386,625, Jan. 30,
1940 (March 7.1938).
G.M.H.
Titanium pigment manufacture. Robert W. Ancruse
and Assn G. Ofpecaaxd (National Lead Co.). Can.
386.623. Jan. 30. 1940 (Nov. 29. 1937).
G.M.H.
Zirconium oxide and method of making. C. J. Kixzix.
and D, S. Hake (Titanium Alloy Mfg. Co.). V. S. 2.194,
420, March 19, 1940 (July 23. 193f).--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 haring their'length greater than
their width and their 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.
ssed la teral is V.C.
values.
.. 44, fioccustannic .ioxide. ydroxA.G.
SSCZXG. 1939). $e rule G.H.
No. 7, .scd on uld be Sect of sstidty ounc of Rji cm. hetero rature.
General
Absorption of lead and arsenic through akin. Anon.
Jour. A met. JStd. Asm .. Queries Minor Notes, 114, 664
(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.5.M.
J Clinical studies In asbestos!*. >1. J. Stone. Amtr.
Ref. Tuoerc.. 41, 12-21 (Jan.. 1940),--This report is based
upon examination of ISO persons formerly employed in the
opening, carding, spinning, and weaving depanments of an
asbestos brake lining plant.
F.S.M,
Compensation for industrial injuries and occupational
diseases. E. R. Koovrt. Jour. Atuer. Med, Assn., 114.
563-69 (Feb. 17, 1940).--K, gives an excellent discussion
of a few of the many Irgal 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 arc given by
states.
F.S.M.
Consider the audience. S. Marion Tucker. ASTMT
Suit.. 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 is technical paper
presentation.
F-F.
Dust-control systems for the metal-finishing industry.
Richard T. Page. Metal Cleanint & Finishing. 10 iSJ
530-47 (1933).--Dust is undesirable in any industry.
Many of the metal-finishing processes, e.g., sandblasting,
grinding, buffing, polishing, etc., are outstanding dun
producers. Control procedures discussed are (I) 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
4
r
8 I 1940
Central
205
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tint
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122
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vho lay tul lea.
ia *Po"
me
ual
ea 22 n, ad >iu he tlL. id* taoia. tot .*nhe ed to =r nt
it.
>57 : he 32 of *d jL r* if
f*
r*
d if *
is er e td a* le
*.
jqv*tigations are of considerable importance and fre
quently accompany the chemical work. The department
j5 equipped for complete minerajogical examinations by
fliicroscopic and other processes used in determining rocks,
minerals, ores, and concentrates of all types. It is fre
quently possible from the results obtained to offer opinions
upon the commercial value of a mineral product or to give
advice on methods of preparation for the market. Chemi
cal and mechanical analyses can also be made of soils.
K.2.
fatal subacute occupational lead poisoning. Werker
ElfltHAROT. Arch. 0everbepath. o' Gesrcrbekyt., 9, 407-12
tflejs*).--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 tbe system for a long time.
Acute poisoning as an industrial disease is seldom en
countered. E. reports an acute case which came to the
Berlin Clinic for Industrial Diseases and discusses its
manifestations. On Dec. 4, 1938, a sprayer of lead, 49
years old, was brought to the clinic in a dangerously ill
condition. Very carefully and fully he was examined:
the next day he died. For several weeks as an occasional
worker he had been spraying cable muffles in a cable
plant. The workspace was 3 x 4 x 3m.; the spraying was
expected to be done under a hood. The worker used a
spray pistol in which a lead wire was inserted and tbe
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 tbe 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 silts. About the middle
of November he had been seized with violent pain and
vomiting; he was off from work for 8 days and resumed
work again late in November. The hood apparatus was
then out of repair ; three other men working in his absence
in the same small space, with very low suction in the
ventilating apparatus, caused the returned worker to esk
for the night shift where he could be alone. On November
30 he was overcome with the same violent symptoms as
before. Being somewhat better by the next night, he
insisted on working, only to return home ia the same con
dition. with additional symptoms; his wife noted that
his face was as black as lead. . details the man's further
breakdown and the efforts of the company physician in
palliation; these failing, the victim was transferred on
Dec. 4 to the Occupational Clinic. The plant conditions
under which the lead spraying took place were examined
and reported on by . after the autopsy. A large hole
was found in the left side of the framework supporting
the hood through which the sprayed lead had been escap
ing into the small enclosure: lead dust lay heavy on the
ttass valves ofappliancesearryingthe-cables; the clothing
and shoes worn by the various shifts were loaded and
sodden with the scattering lead dust; the mask of the
worker was in disrepair, so that he might not have worn it
on his final night shifts. He must have breathed the lead
dust in its most finely divided panicles, i.e., in almost
molecular form. Such an aerocolloid condition ia taken
up by the organism with special ease and constitutes the
highest possible risk to tbe subject. The lungs In this case
were permeated with it. and tbe blood readily carried
this fatal dust to the entire system. From the evidence
derived from the illness, the autopsy, and the plant. E.
concludes 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 l 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. Hence his constitutional resistance was utterly
broken down beyond repair. The lead content of the urine
was 2140 v 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 gs generator. Harry A. Cnms. Ralsh B.
flmzivX.
Wit-ntR J. Darky, /erf. ng. CheTM.. 32
(fl| < Si-62 (1940).--Developments in tbe use of electrical
energy as a source of heal for the carbonization of coal are
described. Illustrated.
F.C.H.
Glass Industry of Ohio. Annan S. Watts. .Ohio
Stale (,'. *g. Expt. Sic. iVctri. 11 [4| VO-13 (1939).--
Ohio is the third largest glass-producing state and has
twenty glass plants. In 119< there was a glass plant on
the Ohio river; by 1833 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 Bar glass. Today this is
drawn from the tank as a continuous flat sheet. Other
important products arc electric light bulbs, fiber glass,
and glass blocks for use in building construction.
W.D.F.
Plant laboratory. K. SrixctiR. Tonind.-Ztt.. 62
[44) 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. Klacoer.
E. R. Gross, a.s*o H. Brows*. Arch. Dermatol. <r Syph-
ilol., 41, 331 (Feb.. 1940).--Much of the industrial sitin
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 (or eight
protective applications are gives. _ Substitutes for me
chanic abrasive soap arc listed. Various kinds of soaps and
detergents, such as triethanolamine soap, naphthenic acid
soap, and tulfonated oils, are discussed. The detergent
properties of the vegetable meals arc not sufficiently appre
ciated.
F.S-M-
Pyrophyttite dust; its effect and control. M. F. Trice.
Amer. Inst, Mininf Met. linger. Tech. Pub.. No. 1179;
Afinfcg Tech., 4 (3| 13 pp. (1940).--North Carolina is the
only commercial source of pyrophyilite at present. Fyro*
phytlite occurs associated with quartz, together with
chloritoid and seriate. All the pyrophyilite marketed is
ground; it is classified by air separation. It is mined -by
open-cut, glory-hole, and underground methods. At
only one operation has work been carried on since 1930.
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; slopes 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. Axon*. Okie industrial
Commission Monitor. 1J, 41--42 (March. 19401.--An
employee of a steel foundry worked from May, 1923, 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 30% 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 36, 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. Lrxov U. Gahoner. Ind. Med.. 9, 45-51 (Feb,. 1940).--Certain
y
tentative conclusions derived from experimental work
upon silicosis in progress at the Saranac Laboratory Tor ^
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
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are capable of producing fibrosis in a normal lung. The
trend at tome of the Saranac experiment*, however, ha*
altered certain concept* previously regarded among re*
search worker* a* died. Inhaled chrysotile asbestos
dbers now appear to be irritating, not because they are
silicates, but because they are stiff dbers. mechanically
irritating to the lungs. Crindtttg theta down very tinely
so that few of the dben wer* longer than 2 microns prac
tically destroyed chi* irritating property. Even with an
average atmospheric concentration of 123 million particles
per cu. ft. of air. no fibrosis developed. If the effect of
asbestos on the lung were entirely chemical, a decrease in
particle site 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
monly recognised a* 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 nonpbrous 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 asbestosis will not develop.
Free silica dusts, unlike those from asbestos, cause a chem
ical form of irritation in laboratory animals. a G. describes
the two histological stages which characterize the tissue
reaction in such animals after inhaling excessive quantities
of pure quartz or (line 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 possible 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. No
fibrosis has ever been produced by single of repeated in-
jectionsof 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 quarts have
been, more or less neutralized by adding small amounts
of different substances, e.g.. colloidal aluminum hydroxide
which gives complete .protection in 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. W. H. Eaahart. Okie State
ftittr. *g. xpt. Sta. ,Vrirr. 12 (2) 23-28 (t!WO).--The
composition of a body may be modified to obtain a desired
thermal expansion. The thermal htory al*.i affects the
thermal expansion; curtain composition* fired ,u low tem
peratures have less expansion than the same body fired
at higher temperature*. Thermal expansion may be
measured directly on a bar or by the interferometric
method. Bodies with a considerable amount of high-
expansion quartz in low-expansion clay may show dancing
tendencies on cooling. Beta-quartz expand* on cooling
and may also sec up strains. The abrupt quartz inversion
point at STVC. may be destructive. Quartz and clays
have fairly uniform thermal expansions, but the feldspars
are variable. Hotel china, sanitary ware, and finor tile
all have thermal expansion curves lying dose together.
The quartz present does not seem to affect them. A
quartz grain shrinks more rapidly on cooling, and it is
thought to pull away from the remainder, so that it does
not fill its recess in the body completely on cooling.
W.D-FReport of Committee oa Ceramic Education. N. IV.
Taylor. C/tairman. Butt. Amtr. Ceram. Sue., 19 (t>!
230-21 (1940).
Report of Committee on Publication*. John D St.tt.t-
vast. Chairman. BulL Amer. Ceram. See.. 19' [til 222-23
(1940).
*
Report of Committee on Research. Axtkvx a. Wells.
Chairman. Stiff. Amtr. Ceram. See., 19 Iri] 214-1S
(1040).
Report of Committee on Sections and Divisions. M. E.
Holmes, C/tairnutti. Bull. Amtr. Ceram. Sue.. 19 [til
221-22 (1940).
Report of Committee on Standards. John W. Whitts-
more, Oiatrman. Stiff. Airier. Ceram. See., 19 [fit 213-20
(IWO).
Roentgenologic aspects of bronchomycosis. H. P.
Doits. Radieton. 34, 287-73 (March, 1940).--The signs
and symptoms or the bronchomycoses are similar to those
of tuberculosis and they are often at fine thought to be
tuberculous in origin. D. describes some of the more
prominent Roentgen signs of the various bronchomycoses.
F.S.M.
-Silicosis. E. R. HAYHuasr. Merck Rept., 49, 6, 3, 9,
23,30,32 { April, 1040).--H. gives an excellent short review
of silicosis.
F.S.M.
ook
Engineers and Engineering in the Renaissance. WtLLtAM Barclay Parsons. Williams Sc Wilkins Co.. Balti more. 661 pp. Price 38. Reviewed in Science -Yew* Letter, 37 [12| 192 (1940).--P. discusses the amazing engi neering achievements produced during the Renaissance.
P.G.H.
PATENT
.
Coating and coioratioa of granulated materials. N. P.
Hajcshbercer (Bakelite Building products Co., Inc.). IT. S. 22*02,002, 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 aluminaces 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 j i I I i i
j
'
* V:1
m
1 A
:3
S?
TC
., T.
.*
22b Ceramic Abstracts
lieen taken of die advanced training centers in heavily in*
tlustrialized cam munities. showing that there is evidently
until demand for this litlil of practice.
F.S.M.
I, Lead content of human blood. Q. Lead as a poison.
J. N. M. Ckaluexs. Lanai, 218, 447-50. 402-63 (March
0, 1940).--Tom psect'i method of determination was used.
Stood was obtained from 2<> normal people and 50 hospital
cases, 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 control* showed a lead content which varied from 30
to {Hi Mgm. per OKI ce. with a mean of 57. The lead
workers, who presented no symptoms of poisoning, had
blood lead values ranging from ikt to I'-i-- gat. per UR) cc.
with a mean of 104. Augmented concentrations of lead in
blood indicate increased absorption of lead but do not con
stitute evidence of pfumhwtn; they are a ccsefuf estimate
of the degree of exposure. Clinical (ladings must still
continue to govern the diagnosis of lead poisoning. There
ia a discussion of the problem and alto of the value of milk
in the diet of lead workers. With a high calcium diet,
there is teas lead absorbed from tbe gut than with a low
calcium intake. Sine.-, industrially, most lead eaters tbe
body through the lungs, the calcium probably acts by
helping to tut the lead in the bones and thus prevent it
from circulating is 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. Caccvxc and L. Dt-
Prisco. Folio jled.. 2d, 7-30 (1340).--A review is given
of Italian literature on the subject which seems 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 3 and
emphysema. Tuberculosis was not found.
F.S.M.
Manufacture of fired clays (brick, tile, and pottery),
A. Cotasorr. Artile, So. 197, pp. 13-21 (1939); No. 198.
pp. 3-9 (1940).--C. discusses the caw products used in the
manufacture of fired clay products, the formation of days,
and their characteristics and composition. 3LV.C.
Mechanism of development of lead anemia: IV,
Pbysiochemicai nature of the splenic and liver substances
which decrease erythrocytes. S. Kin. Jour. Mttl.
Coil. Ktije, 9, lUl-to" (UW9),--After injection with lead
acetate, the spleen and liver seem to contain some specific
chemical substances 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 animat charcoal or kao
lin. Its action was also retained after ultraviolet radiation
for 3 ftr.
.F.S.M.
Metabolism of nucleoproteins in lead poisoning. G.
Micbetti and F. Momso. Rats. Med. Apptieaa Lworo
tnd.. 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 chronicity. _ So 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.
Kature of anthxacofic feci. Experimental research.
A. G. Saveilini. FolU Jltd., 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 iroa participate 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. Foerster. Illinois
.1fed. Jour., 77, 79-85 (Jan.. 1940).;--After analyzing
various sections of the Illinois law, F. concludes that
"any skin disease may therefore legally be an occupational
disease in Illinois,"
F.S.M.
Preventing economizer corrosion. F. J. 5Iarenews.
8'ii. Chtyiootker, 48 (3731 332-54 (l'J4lJI.--M. discusses
the causes of corrosion and gives suggestions for the
maintenance of the economizer.
XLA.1L.
Priceless possessions. L. Gnssxsmtc.' Aui. Safety
.Vries, 41, 26-27 (Jan., 19401.--'There were 1843 cases n't
compensated eye injuries in Mew York State in 1938 and
the cost was 51.163.000. Of these, 50*& were caused by
foreign matter entering the eye and could be avoided by
the simple and cheap method of wearing goggles. Yentila- `
tion controls are needed for eye hazards of toxic diuu and :
fumes, and in the past yeap the Division of Industrial
Hygiene has passed and approved 2000 sets of plans for i
such control in factories. Special goggles are needed for (
protection against radiant energy, and fatigue of che eyes 4
can be lessened or eliminated by proper illumination. G.
discusses these sight-saving means and methods for pro-
meting their adoption.
F.S.M.
;
Two fatal cases of pulmonary asbestosis. . C. V\
Yiguami. Rats. Sleti. Applicant Latwo Inti.. 11, 26-52 !
(194U).--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 j
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 or the lungs and asbestosis '
bodies.
'-
F-S,,M.
t
Unemployment benefits no bar to workmen's com- }
pensation. Anon. If. S. Dept. Libor, Monthly Labor `
Ree., 50, 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.
- scfarAte rirauc.vTta.v3
Basophilic Aggregation Test (for Lead Absorption and
Lead Poisoning). Anon. Ohio Dept. Health. Adult
Hyg. Div.. 1940. 7 pp.--Tbe technique and interpretation
of results of the basophilic aggregation test are given in a
concise tom.
F.S.M.
Legal Aspects of Engineering. W. C. Sadler. John
Utley 8c 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 after 6500
legal cases actually dealing with engineering problems were
carefully analyzed. Cases dealing with compensation are
of the most interest. S. gives a general discussion of the
subject. Cases are given to Illustrate the following points: 1
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.SAL.
Manual of Industrial Health Hazards. J. B. FtcXLXK. J
Service to Industry. West Hartford, Conn. 175 pp. Price *
54.00.--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 givenover to the ma
terials or groups of materials which may cause industrial
disease. For each substance. F. gives the occurrence and .
uses, certain physical properties, the clinical symptoma
tology it produces in man. the physiological responses of
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 gives. _ An ap
pendix includes useful constants, formulas, and _ instruc
tions for the preparation of standard solutions.
. F.S.M.
HUNTER GAS. BURNERS
Latest and mote efficient vertex Burners Tor every gas Gas Burners with Oil. Burners incorporated Gat Burtvert uiuftf two gaset atccr'iictvely
powfb is a S ECONOMY CO.
HURST, NELSON & CO
MOTHERWELL
RAILWAY ROLLING S OF ve*y description r** M*P C1^7.'* r ^ C*M Its3W*<#IM. | C I
warn** *on simple nine
Am M M jWee lMivt Itumkm ^ Ml
THE
IRON & COAL TRADES
' t/iN*DON f icprnntEK . ism
REVIE
Iron-Ore Extraction in the Midlands*
OPEN CAST WORKING AND UNDERGROUND MINING
orMETHODS
LL boutOM
SU1 RFACE WORKING
la tttdtisdi vii
The
append*!
description of ireoert entree*
TV* also of hill end dal* varies alec
with the depth of overburden, since the esc*voter need varies generally
A originally got by band either at out* tisa in tb Kidludi bee bee* taken from the depth of the overburden to Im wor
crop* or not more than 13 to 30 ft. beloRweport* ef the Committee on the Restoration can therefore* talk of o M normal " x
th* surface. Tit* raiattAtomcrit of uch l*ad of Lead Affected by Iron Ore Working, and and dale for a particular depth of .
for agricultural us* immediately ipHtinj presented 00 difficult^.
after the No (tnt
deal*
with
methods
of
removing
if it ia understood that only a very g the over* tfonahip ia meant. The general ten-
outlet of subsoil had boon disturbed; tiio burden, and winning Is underground workings matter of importance in ooQ*ecUou
topsoil was merely thrown on on* aide and than returned without any cost for haulage.
cost* *f leveiliog. When the out ia a deal gullet la loft. This may he oi or 200 to 300 fa. wide and GO ft. de
Ab th* tutu of tin' ctatuTJ mtU steam navvy following up behind dragline K and load- may form * considerable difficulty i
cse*v*on with < tiiwtuat jib m tra ug the uvflfCea4 cat* wagon* 3. The face at f> iron to the quarry, particularly for
duced for th* purpose of motoring th over gradually recede# u the ironstone is removed. re*toretie* work.
burden, hut all tend was still restored by hand- When a quarry was about to become too deep for restoration it was abandoned or tnioed.. Excavators wife then totraduced for (amoving the or* itself. In th* captation of
4*rIopnat du to th* War, th* American
The workk?ing b like a too*able ettff-
(_3) A short j.ib uuntsr ma_y be need 1
con"juncti'on wdftla a conve_yor aa i figv. J. #iesHtr A remove* overburden from the
face B aad then empties the lead ante a uuQ
track, or dumping tram, eo the steel-framed
eoitrejor at C. Tbla (tu up t* th* ether end
Local Objections to Largo Esc
It it the operation of these mnehr has alarmed local opiaioa and which attention to the whole question of t working of ironstone in this country, reaction to the coming of th# largess
tag jib and mechanical digger with * wEdi at D and tips over. The function of th* eon* hoc Veen ta suggest that they are net
dumping radius was introduced. About this vevor ie therefore to move the dumped over* ft is icon that iraaatoo* waa won b*
time tom* treat worn Ant left uoreatored. harden away as far as poeeibla ea that there la machine* euma and it fa suggested :
this we*, at first not so much do* to technical difficulties as to a company going
ae danger, of the navvy whieh b removing the Inmate*# becoming Varied. The overburden la
ought, (n view of th* devastating co to bo a ravoraio* to older methods *
to of butinesa.
damped by Ike conveyer In a ridge and furrow coraty of yvt newer ones. If it is poia formation similar to that whieh naslti from reply that imutme N(d wee be got
TO* position became e**i#oa vtu, to the tlie era of o long jib excavator Vet in a rather arty at V> ft. depth by the eld mat
'ftirwi, Stewart* sad Lloyds left Scunthorpe more wavy line.
sometime# argued that, if the prodr
ftrtffcunfea atoqjfliMjTj
"r'if-49ffi3rc0"B * Iranitcftc lfv wa
,
^kcuvd
f, L--Due-tm Unuo of EiTtiemv.
Fio, 1Siost Jn {itiMtsi us Tteuioiru
and came to Northnnte. Sine* they were late- (3) The overburden can bo removed and mmers they found all the area* f easily get era dumped by % laug-jtb fiuntet. TV* sketches cuetrailed by other fru, and they were .forced (Fig. .3) are of o.fccnb, yd. excavator at work.
to leas* area* of deep overburden. They began These maehinet are the largest ia Europe, and
put to It, they meld invent mv meih
would abolish or modify biU end dole, sogiaesring-divehjpgioiru u* they urpp Cert*mitt#* from th# evidence put bei
rack on thee* with an electric*! xenfater they hove an output of about 500 ton* per hr. included;--
which, with * I cub. yd. bucket (t cub. yd. roll. In fact the whale area uoumee the aspect (1) An attempt might be made to in raprasonta very approximately l ton), s damp* of having gigantic furrows, which are locolly excavator. The present performance ot mg radtue of 101 ft., and a dumping beigtit of known sa 14 hill and dale.** TV* ridge* census function of the radio* of the jib ar
R H.) could deal with overburden up to about predominantly of nbaoil, and in them th* up aagte of repose ef th# dumped soil,
0 ft in depth. '
oil is irretrievably tet The ia* of then* cause thee# two factors era flood, that
Irenssoon k won by n number of different furrows depend* on the rise of the navvy used dal* formation occurs. If the length *
wodunra who** operations have somewhat Ter the excavation. Whom the largest navvies could W varied slightly with *ck hue different effect*. They include th* 'dragline are in mi*, th* dutance from creel ta crest is thou hill and dal* ef the present
which works *n the principle of * rake; the fawn JO to Aft ft., thv depth varying from 10 would not he formed *ed a surface wo
excavator or " digger 41 with a abort arm (the ft. to 16 ft, but where smaller excavators have which, if very irregular, would be touch
"jib") dumping ea to a conveyer or wagons; been used ia the past, th* crest to crest distance level. If tu length of the jib were :
the long-jib excavator which dispenses with the U between 30 ft. sad 00 ft,, and the depth from However, eo aa to giro * choice of
bttor, and th# Lubeckar (land) dredger which li ft. to about 10 ft. The shap?e* and six* of the which each bucket could bo emptied, tt
mn dump sand or other very tight sail evenly. hills and dti** depend at only on the typo of ef th* eutit* machine, which u tires
The dredger create* a* problem of lrUiug bo machinery used for putting the material across, 300 tons, would bo increased to an imp
***** ef the number of small bucket Wads but alia an the angle of repose ef th# dumped extent. Further, |f any attempt *tn
damped, but for this reason it is only efficient in Material. Th* natural eagle ef ropes# of any dump material snywhsr* sear the exc*.i
sand or light soil. Thor* or* a groat number of particular soil composition will generally only bo angle of ropoee of the tipped soil w*i
combinations of these mnehtaoe, with or without found where it ia free to trickle; *.j', on the that the excavator Itself would be hurt*
teed labour, which are used in different quarries, dope of the dumped material stretching down (1) A new cmvafvr might be Jeaic
and it would bo difficult to giro a complete to the quarry floer. M***uremsuti are often position of which could be altered Wtwl
mcoenc ef thsm. The following are descrip tunde ef this aegis for different materials and Joed plseod on it by a small excuvat-
tions ef the work in three quarries which are -umbinatien* ef materials, because it- is this witorts suggested this, but the Commit-
representative of terrain typical conditions.
* ingle that determines the distance between th# ik an unlikely dereJopmeas, The prw.
(l) A 1) cub. yd. dragline at A (Fig. I) re* top of the dumped overburden and the face of reyora caonet be used where there i*
rnevs* the #.ft overburden (including 9 in. of the excavation. These measurement* shew chat of MvrluinttA of more the# 40 ft, b
tspuil) and deposits it st C in a very shallow an average angle of repose it l}.koriuuiriIy w X the strain whieh would be imposed *
" hill and date '* formation which ia lWnJir<ll| vertically, although it may be Antler in boulder trra of tli* conveyor when tb* truck vu
br the jth eub. yd. dragline at C. Tbs opera* clay where there ia a good deal of slipping and xwy from iu point of support, ft w
tie* is then completed by a 4-cub. yd. steam steeper ia limestone. The angle of actual Hill be easy* therefore, to design a convey
and date ia nearly always flatter than the angle would produce better mult* with at v
ef rapes* proper because* the material la partially of 60 ft, or more in depth then are
spread aa it is emptied from the eicoracor.
tho present one with an overburden of
336
The Iron and Coal Trader Review
September 8, 19.
Fatalities from Silicosis and Asbestosis have Wen nidt iLnfof* to And and efficient lubititgtM fof siliceous piwritb . THEIR INCIDENCE IN INDUSTRY
, a namlmbU ntaa; U othr* it it
The problem* a**ociated with lilieMii and ubettoeU monp*t .Industrial wknicd *tprinati w the pnwttt*
worken are receiving t!oi attention* The former hu tended to increase, Aiumi for flitt china bddiaf; (S'*1
and die Utter, oa balance, to decrease. In recent year*
`
for titicwtfi MAUrid in partiog pwd*i npi.Nli4 itmifN far mH mf die*
inf; (4) MMilicwn feaUriil lw fci
SECTION* of the Annual iUpOft* of the
*o that *f tifdnaf Ok* lir% kekt oad fa d ihv cootfag mi iMli end 1"
Chief Inspector of Tnctoriea dealing
mi nrwl furmaevs or (MttniM, o* * pot
Mitwid for alia brisk* for Ji*
vith health refen to the queatioa of dust Muter IS 4 glam rnHtt, ooe ** caginc driver in and who furnaces.
end it* ilfvcd, including silicoaii and 4 stilt* bride vorki, uf owe a grinder f n-
tabntodi. It U pointed out that for tome jeon inn*, particulars of the total number of death* from these two eaueoc, which have
been Intniigntd by the Department, have
been g,iven and brou.g. ht u.p to date. Tbeae figures have been ipeciaUj useful from the
fractery brick*, the r*mefadf Wig oomcfaied
with pnenm fa the getting. crushing, grinding
and mancfarierfag of refractory nalwitlt
The tabic ala# *hew the fatalities from
--Waiati* and aaboatm with tabmulwii com
fag to th* Inspector** hoowfaige and favwatifatod daring the **n in question. The figure* giren
Hydraulic Stowing In Iitdfc (Ciedwlei /rent pajt 23&}
livrrt waling water to dir lonioa gland
Mnd pump, bcaliog water may be led
,ZUlo_Jr_a' g*
at '
therivceoriliwearyteirtstherlfowchoenn_ta_t_hine*__f*ir*
pntfticol point o( Ti.w In sidmfth. inJl-
" OiU#r C of Film*!. " .r. th. ,-
**fi uiVij fai-''
tion of preventive mtuurtl of tlie nweewaary W af um w which " XUwn of the
" nrlir.a- - l-a--r-g--e basin he* been eat.'
eUndard in procviin exposed to rfak. Of w*f entered an the death certificate* u the dean scaling water ie obtained direct frr
much importance and more geoeral Interest.
* death, them figure* being nip river# The suction pipe is submerged
-however, -ia th e trend- of mortal-ity rate* f-rom pl.ie.d h-y d.ie._e_o_urtea-j mof th. e *Re-gistrar Genneral attached by a special flange ta the pumf
it... tiMUn *itb without tuboreulmii. J*
tf It! railed or Covered by a winch mounted
wwhhilci-hti (ton. ,,whhe.nB compwiKa ii., nme.Ade. .afftte.,r
_ number of j-enn, reHeot t.he ,,eff,ect!ro_ne*#, of the preventive measures metalled* For this
`""V ,rtr lhn"* >
h*` I* ti>
majority the snujistisA ef the Jwtaief appeared
out to hare iirohiH fult from stliea er uUitd.
and it i> **u recognised that fibrosis may be due
pontoon. 0* thic arrsagomoat flexible be is net needed on the suction side, an quantity af send to water i% nfshud **
From the delivery side of the pump th
purpoee, comparison of the figures of two te causes other than the inhaloijmi of dust, an| water mixture is ceerevcd hr means
ouceetsive yean is of no value and sometime* Those return* ore Indispensable sinre, fret* time artnouml Uexible boe* pipe te a line ei
Rlislendttig.
te time, they pmrjde the starting paint n( *tcvl pipe* in Ibft te Nit, lengths; fiti*
Table I slmws deaths attributed to silicosis farther tnrsotigation which prevideo valuable Virtiulic joints; the pipe rsego is c*rr
(with er without tuberculosis) during the last iefemutioa,
. tjatv in the stream. The pipeline defirt
Tint f,~Orridi frmm filiwi* *f tie
,vr.#<^ SlUCMl. ud Atbutod* vid Guicar of the
likWi e*d jjilfNifti (feflend4 wd irdiit
Lung '
niiton iota noieJ wpor vale of $ ton* per mm. The sent
In TMt rr, d onnlln. k Wo nta "g-"!* "j* UTljl'Z'mU
Oiseaoe nod loduosey. im. ^ 1630. IMT. 1034.
Sza-Ti
dSr^u*- *
SUtcosla t--
Rvfmeterif Motrin., PutUiy. maitulkettiroof Sooditone uuaerjptng
aM rfrwtnf .. ,,
f1if2i
46
9 i 47 64 43 *16
12 4f r?*'"
V
^ TW <! conHioo too ncb .(. bow, d"' mnoTmioo* ^ Wirww, dinct to tb. Mt cor.TM
27 ITM s^t.tetssTi,sa! --->* -*-
- * -**"
fiandatoue maaooo yndnMiat.. Saod bUmfaa ..
#. <1 #. a .. 14
94 24
iu . i*
\9 u
.91 29
ifsjor points which win have to bo settled are:
t S?* ?!? * iri"XSS *be**U *! S* \***
Sand-Drying Device The sendwwotar miatre-4^ weight et
gleetriiwisi w4 rieaw'
they preface **A U *ahKi% rancor of tiio lung mmtMf 4 ptrtl ,4*1 to { ef watof-
fag nf vaaeifiee ..
gteee. peblik>, list, end
send mdiifi|
,.
Steoint powdorir
Mnsnctunef ..
Ea*od and (Ih
* makers
.. ..
1 1 1
4S
14 2_ 1_
2 r to prodoee ht W the latter, do either ef
th. Cttom of the separator thro
4
these two suhotancc* act as specific mrcinoccni* ^^4 tjUo over a diatributing [date
agents like Ur, er b it that the dieeaoo they pro- 4
Ult The drying Uls r
1
duco only prepam the soil for the Mturranr* of of 4 ^ri<t dtalWw trav*, 2 n. deep, cancer* The foHawing informetinn has been . . ro-llers; eac*h tray ra' nuina a mixt-
fflllwW frnm the Inspector's records, N'o au graded slag which is kpt ia place by t in
Coapo mtwr iTripoli),.
Abrvive-wlMel mane-
factor*
.. ..
XkUstou* ilnninf *.
Slat* drrwuftf with ond
Cfactrieiaa at Msel
foundry .. .*
Slate gueribtng and
diMmng ,, ,.
t t -- a
-- -- baa been inditded in which a post-mortem exami* imn pUtei perterated with l in. holes.
aatlon has ant hoen mode.
Wit is driren at a speed of 10 ft. pe^
\
Among M Intel cases ia which silteonis ef Ttirre rollers of s^uevxecs are placed eguidi
1 *1
sillcoais with tuberculosis was present, cancer of iliMig the upper belt surface, sad a re the tut woe aasociatod In 23 cases (2.4 per prongs placed it series along the Wit tu
--
I
cent.). Of tfint 33, In 17 it w** nnwirrH that sand over *e it is carried forward. The the esacer woe the primary cause ef death, and ind prongs help in th desrateriog of tht
10
T In fi, silicosis nr mlfrasis with tabetunlosia. wliilat the slog is the trayi allows water *
Granite ^ttaeTyinf sad
Among 3t7 deaths which were investigated far- tst not tite send.
dimfar ..
I *
Teaori otinlng |Hwagv
. Mtfaeicj .. Giars diggers ..
.. .*
4 |
. --
Cool rnlafae .. ,. 111 136
Gotd nbwf (South
Africa)
,, ,# 19
fi
Tie Mining .. .. 33 24
ttwa or* (hoe motiu)
M-f
.. .. 11 .
Lead swrisf ...
2
Copper mining .. .. --
1
Boryt** otfamf
21
Itjmng ewfio*ic
1
Total i Hlicmfa ,, 293 3
JLibriUm.. . ,, U 11
I I fag the same period* owing to the possibility ef The sand issuing from the drying be-
2 1ST
#t _ 177
silicosis being present, post-mortem examination Tomfied w'tilioosis but esmeev of 'the long war found is IT cases (4.B per ml).
Similarly with eoWaUsia* among 103 fatal
tains by volume approximately 10 per cr
water. The sand is 'delivered fmm the the drying'WU direct on to 1 30-fa. tro Wit conveyor which delivers it fata the
16 36
|a cane* fa which aabesteate or asWstosu with hunker. The belt conveyor elevates th.
20
Coherestons erne prmst cancer of the lung wu aasociatod fa V3 mm (11.6 per cant.). Of these
43 ft. in 136 ft. run to the top of fbo b en accouat of this grade oolr fairly dr:
i* 13 11 l 1 1` 2 3! 3
12. fa fi it ww cuetidervd that the csocer was the primary caose ef death, and in fi, asbestosis
can W carried.
.
The sand is delivered by the Wit convey
or asbestosis with ttiWnfab. It is dear from times Incomplete tgurvo that
a specially constructed hunker holding m mntvly 1.006 ten*. On the omfanidc
extnmlcd inquiry and collection ef data and hunkvr runs the single mil around *hi
4l j 430
evaluation of age incidence and ago distribution nrul InwWtf of the serial ropeway gr are necessary before any conclusions can be after Wing drlivered from the rope. 0
u : arrived at.
rirfa that* are 7 shatt* which dnUrer *
The Importance ef the mwoi careful pal* ,h<>
the rreuliter at the Witnm
Other rues of fibre*** ,, Ufi ** w | au *"rt*
U mpliuiml W * Kw.t ,huU
th. ,,,,J ,,,tflor ts th.
Grand total
.. 44!
663 i 0*2
four rears, together with the industries cow runted. In faetiiry rase*, the cause of death has Iwm Wne out Uv departmental favc^iga-
Cain* In which mkvd^Te examiaatten revealed
nnlv advanerd eabestosMi, but what appeared te he a small blood dot in * bronchus turned out an nirfMoipid exsmfastion to W a carcinoma,
and aim another roan fa which litleou'a tulwr-
ia of a simp-le type, and..is.kept i.n pfat balance weight. A one-ton capacity bn filled to fi *ct. through on* ef *th shut*
11TM. Til. ..nt. of i.du.tnn mn 1. notaJ,
,'T"""* *" F*"`
and if spare permitted to give in detail the pro- ia
Luxemburg i Iron and Steel Output
tiw nrtiipAtiwial history in each case, the very widvsprewi nature ef th* risk wentd he itilt mors
evident. Fur example, refractorios' indunric* include amongst the 52 fatalities threw who*,-
Substitution of Siliceous by Non-SULceou!
Material!
jh .mrMM fa which th* risk of silicosis te
ooriow* and uncontrollable or only partially m.
1936
Tie-irOu mt|wl.kiM*V*TC in 3*,1y
1*4.SM metric tons (IM.MJ (mu fa J*m J.
Iir.DSs tons in July. 1911). ft#! pnvtnct:
irr,(J4? Ion* in July, against lir.Kt ton*
* t.v. tuumn oat*.
w.c.1, (run u. iui
Vm
lw,
croltihfa. the prsveation of silicosis lies either ami IMMH tens in'jlvv fall. A total nf fa substitution by hartnlesa mtUrisls or at the n*cw were m blast m July II.
ffcit ***9*tJn* ftfbllifctd f* promote
**wj tJreu^ltf *if*en
cancimi^
wJuiffwiil mdicii* ind frunttic
^9fy- T tllt nd H trill contain
r' mwi Jtam*, nportt, diftth,
**f ptoftontalionit to^etbtr
ttrort* corrfni>H. TJt* ^ditoriil pol-
y ti to ncour*?# frank diieiion.
Ito kiii cantfSbuKon* r invSttd.
*#$. U f. ftt OS.
V6
Tli* 4 . rt wiH irtiw tc m cKcV 9 fit* *ccwcy af 4*to prmftd,
b*f b Q other r*tpft ftcl*4 mJ pWow *f which vpru*ori h *IJowoJ r thi epfatofti of their iirflun fb* dihri reserving m *1] *** fbo right to comment on the seme, So tfi* cur
f*nt or ooy tubte^uent tuuMi * they
my be bidSood.
Th Journal of Occupational Dilute* and Traumatic Surgery With which arc coniolidatad "The Induitrial Doctor" and "International Journal of Medicine and Surgery."
The Science, the Law and the Economics of Industrial Health
/oiume 9
FEBRUARY, 1940
Number 2
General Motors Corporation Medical Conference
--Dayton, Ohio, November 2 and$, 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:
Tiursday, November 2:
WTORNING Session: Chairman, M. M. Skater, MD.
''I Medical Director, Frigidaire Division, Dayton.
I "Recent Developments in Relation to Silicosis,"
. IT. Gardner, WD., Saranac Lake, New York.
A Plan for the Control o Tuberculosis in Industry,"
Tax Burnell, M.D., Medical Director, AC Spark Plug
'ivision, Flint, Michigan.
'
3. "X-Ray in Industry," M. William Glut. MDn
iurley Hospital, Flint, Michigan.
.
4. "Preliminary Report on Hygiene Studies of Weld-
tg," L. B. Case and V. J. CastrOR, Industrial Hygiene
aboratory. General Motors. Detroit.
\FTERNOON Session: Chairman. A. L. Brooks, MU, "a. Medical Director Fisher Body Division. Detroit.
3. "Recent Developments in the Occupational Denu des," Marion B. Sulzberger, MU, New York City.
6. "The Course of Disabling Morbidity among Indus-
ial Workers, 1921-1938," William M._Gataitr. DJSc,
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,
MU, Medical Director, Hyatt Bearings Division, Harrison,
New Jersey.
*'
14. "Early Diagnosis of Acute Appendicitis," C. Rush
McAdam, MU, Medical Director, Fisher Body St. Louis
Division, St. Louis, Missouri.
AFTERNOON Session: Chairman, F. B. Wishard, MU,
-Ia. 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- Hnx-
tkbrant, MU, 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, MU, 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.
Poborskt, MU, Medical Director, Electro-Motive Divi
sion, La Grange, Illinois.
'
' S. Public Health Service, Washington,' D. C.
7. "The Industrial Nurse," Harold M. James. MU,
Except for Dr. Sulzberger's address on "Recent
Tedical Director, Delco Products Division, Dayton.
Developments in the Occupational Dermatoses"
8. "The Doctor's Fart in-.the Personnel Program," eorce A. Coburn. Personnel Director, Delco-Remy Divion, Anderson, Indiana.
J'VENING Session: Chairman, Walter M. Simtson,
all of the papers given at this Conference are in cluded here in full text, in the order of their places on the Program:
-r M. D., Director. Kettering Institute lor Medical Re
arch. The Miami Valley Hospital, Dayton. 9. "Relationships of Industrial Medicine to Private
Recent Developments in
ractice." Stanley J. Seecer, M.D., Chairman Council on dustrial Health, American Medical Association.
Relation to Silicosis *
10. "Unfinished Business," C. F. Kettering, Director rneral Motors Research Laboratories, Detroit.
LeRoy U. Gardner, MJD.,
riday, November 3:
Director, The Saranac Laboratory for the Study .
ORNING Session: Chairman, G. L. Bird, M.D., Medi-
of Tuberculosis, .
. Director General Motors of Canada, Ltd, Osha-
rio, Canada. 1. : Practical Approach to Supervision of Mental ulth in Industry," F. S. Parxey, M.D,, Chief, Division of dustrial Hygiene, Dept, of Pensions and National >alth, Ottawa, Ontario, Canada. 12. "An Example of Industry's Participation in the iti-Syphilis Campaign." P. J. Ochsner, M.D.. Medical
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, 1940
, 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 every 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 Lean' consid
derstanding of the action of irritant dusts upon ers2 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 oractical 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 wearing mills contains many more long
were longer than 2# 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 1 would point out that in a jected with excessive quantities of pure quartz
previously reported experiment* one third this or fiint 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.2 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
injection 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, ]$40
id COIK
car tis*
ge V -are quartz, the pe, face of terisrie consid' mds of itching
dozens known icy are recogdon in greater licates. lemical enUne, irritatysical, ` these
>e indi-
it verv . This ion, for d.mills n it, _nd : fabrilerican te puzixperi'e dust nd ex e spinre long
ints to .e solut com e been or in quartz sion, it : place arnroilere is mloma . The e cells that in jle for
fihro-. #1' ia. trans rapidt twohronic 1 over tissue.
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
vested 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 invaolif- 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 a corresponding reduction in red blood cells. The
15 to 30 minutes after injecting fine particulate blood no longer clots. There is no hemolysis.
silica. In the test-tube traces of dissolved silica Animals that have recovered from one reaction
are only discoverable by an exceedingly sensitive seem to acquire a tolerance so that in some in
. colorimetric reaction after 12 to 24 hours. Possi stances at least twice the former dose may be in
bly "vital" factors may accelerate the process, but jected without symptoms. The degree of toler
no means of evaluating them has yet been dis ance, however, varies widely in different indi
covered. No one has ever produced fibrosis by viduals.
y
single or repeated injections of the various forms These symptoms are not influenced by the in
of soluble silica. The effect is apparently not due 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. - lit years of experimenting to discover the mechanisms by which free silica exerts its pe culiar effects upon living tissues we have re , peatedly observed evidences of a specific toxicity. Guinea pigs, injected intraperitoneally with large
quartz particles less than 3ft 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 ticle suspension, although the amount of soluble 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.- Redlins were seeking an avenue for the of different substances. Colloidal aluminum hy
quantitative introduction of silica they tried -in droxide gives complete protection in & -dilution
travenous injections into rabbits and discovered of 0.03; colloidal ferric hydroxide is much less
the method which we now use as a standard for effective. Animal charcoal cannot be injected, be
' comparing reactions to different dusts. But in 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 tod 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. Farther experiments are in progress
ticles but only when the quartz grains were 3/t 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 defined, 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.
* 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 or 4 cc. of a 1 % suspension of 1 to 2/t quartz partides in physiological salt solution. The reaction
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 o' neutralizing the action of silica. Unheated sus pensions of the metal are just as effective as the hydroxide.
Page 48
INDUSTRIAL MEDIC
February, 1940
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 3/t 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. feet 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 infiuence,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.
|
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 3j* in diam eter and possibly by the observations on neutral
'4
THIS observation brings us back to the cause of these progressive changes. Apparently? they are initiated with degeneration in the pri-)
ization. Any effect due to preformed soluble mary phagocytes, an effect which is exactly paral-'
silica liberated in the suspension before injection leled -in the histogenesis of tuberculosis. Some;
has been eliminated, and no active soluble silica years ago I published a paper calling attention!
could be demonstrated in the blood of an animal to the similarities between silicosis and tuber
dying in shock by transfusion into a second host. culosis.5 In both of these diseases the primary?
Everything now suggests an effect taking place irritants, quartz grains or tubercule bacilli, as'
very rapidly at the interface between the quartz the case may be, intoxicate the phagocytes.' In;
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. The manifestation of acute toxic symptoms by
those species of animals which develop silicotic fibrosis most readily and their absence in the dog, which appears to be much more resistant, sug gests that these immediate reactions may have some bearing on the etiology of silicosis. Until
cells of the Langhan's type are produced in each? disease by stimulation and repeated multiplication of the nucleus. In each disease many cells die:
and their degenerated products are liberated in the tissue spaces. Incidentally it is the pabulum' of necrotic cells in silicotic lesions on which tu 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 sis as it is in eliciting acute symptoms of intoxica
tion. Many injection experiments have convinced - us that quartz particles over 3p in diameter are
bacilli are most frequent. Perhaps they not only
cause such caseation but they themselves thrive on it. Coincidentally more cells migrate to the area and proliferate to form the granulomatous
of little or no physiological significance. The fact that the lungs of persons exposed to most dusts contain few particles larger than IQ(iJa diameter has been responsible for the establishment of this
nodule that is characteristic of each disease, t
Finally the production of necrotic tissue, high in lipoids, by two very dissimilar primary Ini' tants recalls the experiments of Fallon* and his
size as the maximum important in dust counting. hypothesis that it is these lipoids which are di-? As a matter of fact we know that with some dusts rectly responsible for the formation of the granu-j there may be many larger ones. While it would lama. 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 3fi 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 cient surface of silica to the fluids. Recently Mr. Dworski decided to test this reasoning further by
injecting graded doses of different sized quartz particles which would all present the same total surface area. He found, however, that regardless
It still remains to demonstrate the nature of the primary injury by each of these irritants, and it' is this problem that will probably engage our at* tention for some time to come.
Bibliography:
1
of the total surface, silicotic reaction only de l. Gardner. L. U.. and C cm Mixes. D.E.,: Studies os veloped when the size of the particles was 3p. or Experimental Pneumoconiosis: VT. Inhalation of Asbestos
less. On examining his material it was-discovered that with particles 4 to 5in 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. /Indust. Hyp., 13:63-63 and 97-114. February and March. 1931.
2. Gardner. L. U., and Cummings. D. E.: The Reaction
to Fine and Medium-Sized Quartz and Aluminum Oxide
Vou 9, No. 2
INDUSTRIAL MEDICINE
(
Page 49
Particles.' Silicotic Cirrhosis of the Liver. Am. /. Path., tion. This is done with the intent of placing that
1933:9, Supplement whole number 34, 751-763.
.3. Timothy Leary: Personal Communication.
4 Denny, J. J,, Robson, W. D,, and Irwin. D. A.: The Prevention of Silicosis by Metallic Aluminum, Canad.
IS. A. 3* 37:1-11, 1937. -5. Gardner. L. U.: The Similarity of the Lesions Pro
duced by Silica and the Tubercle Bacillus. Am. /. Path..,
individual in industry where he or she is best physically as well as mentally fitted. This exam ination is not done for the purpose of either pass ing or rejecting that person for employment. This pre-employment examination gives the examining physician the best possible opportunity to detect
13:13-23, January, 1937.
6. Fallon, J. T.: Specific Tissue Reaction to Phos
pholipids: A Suggested Explanation for the Similarity
of the Lesions of Silicosis and Pulmonary Tuberculosis.
Gnuxd. M. A. J, 3 S: 223-228. 1937.
.
pulmonary tuberculosis. Dr. Robinson'Bosworth, President of the Illinois'
Tuberculosis Association, states:3 "85% of adult 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, MJD., Medical Director,
that such an examination is not complete without an x-ray of the chest.
We believe, with Dr. Andrew R. Riddell, of the
AC Spark Plug Division, General Motors Coip, 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 of the safest places to be in this country is at work. Statistics from the National Safety
states that1 "the individuals must present them selves at least three times--there is considerable disruption of work--even after most careful ex
Council seem to bear 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
With such improvements, the consideration of culosis is discovered are sent to their family physi
ie 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 no adult group throughout the country can so much be accomplished in prevention and early recognition of this disease as in our industrial in
at what future time those persons may be pro nounced employable.
Applicants with arrested or quiescent tubercu 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 clear: The general health of every three months.
the employee must increasingly become the re It has -been increasingly evident that cur- 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. O. Sapping- then has industry wholly discharged its duty to -
ton states that "during the first year of the oper 'the community.
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
claims 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 (b) After absence caused by an illness.
mind certainly should be actively engaged in the (c) Re-employment following seasonal lay-off.
problem of the control of tuberculosis. Many of (d) Transfer from one type of work to another. ..
our industrial institutions have already shown, by (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
THE PROGRAM: 1. The Pre - Employment comes into our medical department for a general Physical Examination. Every prospective physical check up at least once each year. emplovee is given a thorough physical examina Two types of periodic examinations deserve
i n * * %
it k tK
&
n
-Ti *
Page SO
INDUSTRIAL MEDICIN1
.4
f
February, IS-KT
special attention. First, the medical department plant safety engineer and again adopt "preven
requesting the employee to appear for some spe tion" as our slogan.
*
cific reason. Each employee has his own physical As Dr. C. D. Selby has stated, the industrial
record card. His visits to the medical department physician is the health officer of the plant.4 "It fc
are recorded here. If it is noticed that frequent his duty to locate, identify ^nd determine the im
visits are being made for colds, bronchitis, loss of portance of all occupational and environmental
weight, feelings of fatigue, etc., he is requested sources of disease or health impairment and.to.
to appear so that we may get at the underlying see that they are corrected.'*
.
'*
cause. These examinations are always accom In relationship to tuberculosis he must know if
panied by x-rays of the chest and if the disability "exposures" to the inhalation of dust particles ot.
is from early tuberculosis, we are able to detect it. obnoxious gases and vapors are present within the-
The other type of periodic examination is most plant Also he-must pay attention to overcrowds
gratifying to the medical man in industry -- the Ing, proper lighting, ventilation, arranging restjE
physical check up requested by the employee him periods for those engaged in strenuous or necew*
self. This is, indeed, a measure of the confidence sarily rapid operations, and have knowledge of tht
that has been established between the medical de toxicity of materials handled.
partment and the worker.
Dr. Hamilton has listed definite industrial poiJ
Cooperation with the family physician is of sons which are capable of irritating severely the-
paramount importance. When some disability is bronchopulmonary system and activating a pte^T
uncovered and it is discussed with the employee's existing pulmonary tuberculosis -- chlorine gas
own physician, that employee realizes that the ammonia, benzine, brass fumes, phosgene, nitric?
corporation is not attempting to deprive him of acid fumes, selenium and vanadium, to mention a:
his job but is trying to keep him at work by im few.
*f
proving his health. Again confidence is estab The danger of exposure to the inhalation of.
lished, and that is the best foundation for a suc dust, especially silica dioxide (crystalline silica)]
cessful program to maintain a high standard of is only too well known. It is not within the prov--
health within your organization.
ince of this paper to discuss silicosis. However^
One striking example of such a relationship is as Dr. Riddell4 has stated. "Tuberculosis is the
of unusual interest in regard to the .tuberculosis commonest and most important complication in-ft
problem. After the installation of excellent x-ray deaths among silicotics. Therefore in any dis-; [
equipment in one of our plant hospitals, it was cussion of the control of tuberculosis in industry;! f
suggested to the employees that they take advan the subject of silico-tuberculosis must have its.
tage of this opportunity to have their chests place." .
.*
i
x-rayed. These were all old employees, some Dr. LeRoy Gardner* contends that "silicosis is
with service records of over 20 years. The re the menace that it is because it specifically pre-
sponse was amazing. Over 4600 employees re- . disposes to tuberculosis. It is the latter which is
quested the examination during the first 10 responsible for disability, lost time, and, in many
months.
-
cases, death, and it is really tuberculosis against;
All of these employees were working every day. which we have to fight."
%[
They considered themselves in excellent health-- This statement has been recently challenged by |
so did the medical department as a matter of fact, Dr. George Omstein.,<`
^[
as their previous physical examinations during Whatever the conclusions may be in the future-
the year bad shown -no disabilities. However, 12 concerning the exact relationship of silicosis to ,
cases of early active tuberculosis and 42 cases of tuberculosis, the industrial physician must conf
arrested or quiescent tuberculosis were brought tinue his attempt to eliminate dust.
^
to light. The active cases are all under treatment Dust counts should be made to locate the points
--nine of them have been referred to sanatoria by of greatest hazard. Consultations should be held7
the family physician. Active tuberculosis has also with the safety engineer as to the best type of con
been found by the family physician in the house-^ trol, whether (a) mechanical ventilation of the
holds of those in the arrested groups,
* positive or supply type or local exhaust systems;
. 3. Control of Tuberculosis Within the Plant. (b) isolation or total enclosure methods, or (c)
If there is to be real control of tuberculosis in in respiratory protection by respirators and positive
dustry, the activities of the industrial medical de pressure masks or helmets, are to be advised. `
partments must not stop with examinations with
Tin the plant hospital. Dr. G. T. Drolet4 has shown conclusively that
HE purpose of industry is manufacturing-' Often the installation of adequate equipment
where there are bona fide cases of active tubercu
is expensive. This adds to the cost of the rm'anu-
losis the results of treatment, irrespective of factured article. It behooves the industrial physi
where or how, are still far from satisfactory. In cian to study his problem with care. Our experi
other words, "the hopeful sign is steady reduction ence has proved that when management is in
in the number of cases and not what happens Ip formed of the hazards that are present and shown
those who actually develop the disease. Progress the necessary steps toward their elimination-
has come by prevention and not through treat whole-hearted cooperation is immediately forth- !
ment."*
coming.
'
We must take a page from the program of the To Summarize; A plan to control tuberculosis
mo
yen- '
:*im-
mtal d to
rar if or * the owd-
rest ecesf the
poir the pre
gas, litric Ion a
. *
n of ilica) provever, s the m in
*
't j
sis is preIch is nany jainst
ed by
future
sis to ; con-
points - held if conaf the items; >r (c) asitive d.
uring. pment manuph "si-
L shown nation. forth-
culosis
Vol. 9, No. -
INDUSTRIAL MEDIC*.
Page 51'
in industry must start with pre-employment ex all know, from the several years that industry has amination.* The majority of employees firs: enter recognized its use. The contact of the roentgen
' industry' during the age period when adult 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 to be the new awakening of industry to the importance
detected. When arrested or quiescent cases are of preventive medicine has come a change in the
discovered, we feel that it is industry's duty to 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:
results most economically.
In the past two years the author has had the
'
ICO. Sappincton, MX., DR.P.H.: Central States So ciety of Industrial Medicine and Surgery. May 1". 1033.
2. Robinson Bosworth, MX.: University of Michigan
opportunity to organize and try out, what in his own mind is a model industrial x-ray department,
Postgraduate Lecture, October. 1938.
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, MX).: Am. Ret. Tuberc, Feb_ 1933. 5. James A. Britton, MX.: 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
ft. C. D. Selby, MX).: Paper presented before National
Tuberculosis Association, Los Angeles, June 23. 1938.
7. Alice Hamilton, MO.: Industrial Poisons in the
' United States. MacMillan Co.
-
ft Andrew R. Riddell, "MX.: Trans. National Tuber
culosis Association, 29-1933.
efficient equipment. And it has been thoroughly 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. LeHoy U. Gardner, MX.: Third Symposium on Silicojis, 1937.
. 10. Gtoner Ornstexn, MX.: 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, MJ3., FA..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 years in the field of x-ray :n in 600G 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