Document BR1Q45NEB1KE5XKm6eEvxoBro

T*% ember T* JJ :><.sia*.n 4. ' t) 1ST*, .; j r* i iw. CD n ujft i iMa >* CERAMIC ABSTRACTS Compiled by The American Ceramic Society 1948 CHAXLXS S. PSAACt. Editor Maiy J. CiSS. Auistanj Editor DoionfY Oo.vokvz. Editorial Asuitant Commute on Publicatiom: X. C. Lyon. Chairman; Xaju. ScjnrAJtTrn-AS.8**. R. E. Bixcm. and J. J. Cantuu> Tuhxical Addicts: L. C. Fauii, Rasth Rose, and A. W. .Mask A H. Adams F. C. Armace Wilfred Ashworth X. X. Ault Walter Bank L. R. Bnrretl R. Birta L. Bamajhi W. R. Seek J. J. Beinlich A. C. Sevan abstracters Associated Techcical Services British Coumic Research Association Bureau International d'Etudes Techniques Ceramiquo A. J. Biddulph R. H. Bollinger Claudia Boynton Ian Campbell O. S- Oouflas W. I>. Foster J. J. Frenkel R. A. Grejory P. Grodxinski A. J. Haecker. Jr. Max Harttnhnm M. P. Haydoa F. G. Heck I. Hochown R. H. Hooker G. M. Huu Collin Hvde J. F Hyde L. J. Jacobs 3 Z. Kamieb D. F. Xinc M. M. W. Kleimats X. J. Kreidl S. M. Lanj E. D. Maher F. R_ Matson L. R. McCreifht L. M- Memtt J. G- Mohr j. M. Xoy S. S. Obenshaia T. G. Pett D. G. Pierce Alexis Pineus W. J. Plankenbom J. E. Pnestley A. T. Prince H. X. Richardson X. SchreweUus A. B. Searlc *. 0. Sesnmelman P. Shoukwiler Hans Thurnauer W. 0. WUliamsou Publication. Ojfre: COth and Northampton Streets. Eiston. Pi. Editorial O^cc: 2523 North Hi(h Strrtt, Columbus 2. Ohio n,: 'C&1 , St) /twi3y. Af:.. i; ! "0* ueo Ceramic Abstracts November l!U: inert css curtain* inside funutia. and simplified. smaller How to auk* a Silk screen. Ano.v. Cntm. M so lilanu; >31 prediction* for whitewure wnteb mu-luile 111 I 117 I tU4ril. CO.lt greatly shortened maturing schedule*. uusiom-muile kiln*, How to st up e simple perpetual iovedtory system. unbreakable china. uncuntuainutovl raw material. hamljiug 0. L. Cut'CK. .In/. PiuMl J., 22 [31)1 4ii-4t> U94b). limed to nuke storage unne*ary. automatic hatching. 8 system through which any manufacturer at supplier ,.f vating m a friction of tlte prevent time, faster jiggering. numerous articles van determine profit-able items, rewrv.- radiant lieat and atomic fuel, and rapid decorating: id) stuck quantities, and control production, mark-uo*. .u-.d prediction* for gla* which include nnailer plants, pneu reserve* uf raw material* can l>e t up umug 3 X A in. iiL- matic material handling. pr&iittering for fast melt*, trend -- curds m a visible reference type file. Suggestion* are toward automatic forming, combination anncifing and uttered concerning .iccuai tluta to be entered on each curd. heat-treating, lightweight {Luis, throw-away container*, A ficticious case illustrate* Che value of such a i-yecem. and oxygen melting. Twelve charts 'rith curve* predict A.J.ll. the rise and fall of market condition* for major appliances, i. Isasersioa 'media eopttiniog methylene iodide. linn. architectural porcelain, porcelain sanitary ware, hollow 9 "ext l. D-vJt*>s<ua .!. Minimi., 33, J4i4.'i2.i l9-*b).--The wore, dinncrwjrc. door and wall tile, vitreous unitary uocniliic** of methylene iodide in Immersion media i ware, clectncai porcelaia. (la** container*, flat class, [la- vmp.uisuefi. The nonlinear relationship of indices of ru tableware. and structural [lass.- C.C.8. fraction to composition by volume uf some liquid* contain. CoBtrolliac ebnornui dust cxpoiure*. M. W. Thomp "* ing methylene iodide is shown by experimental data. An son. Occiiftitwmd Hazards, 10 (4| 12-U1 1 1943).--T.i einuirioul equation hit* been devized for calculating removal of dust from places of origin by mechanical means indices of mixtures of methylene iodide ami l-htomonupii. jed by moistentn[ material* and air, as adopted by tile thaiene from volume percentage data: < 1.5237 -- American dinnenviare industry, is discussed. 21. Ha. o 1/ll)f (4ou9r 4* 37*'), where ss is index and t is CH:(; Dried asaldiag xud. P. XlUUUvj. Fonderit, 1943, No. 29, U7C-7d.--The result* of testa are riven in oyrva. of humidity content alter drying, density a* a function of humidity, and compressive *trcn;th as a function of hu midity and of exposure to air. The optimum valued of a -and containing 13% day with u fineries* of A.F.A. Ill) were obtained with a humidification of 7%. foe plasticity. Sl~. for cohesion in the jreen state, and tti'c for strength after drying. To obtain a fine surface on the east piece* the dried mold* should be canted with stove biuelc contain ing about 8% volatile matter and 23 to 2DC'* ash: the [ruin size should be les* than 0.7 mm. For steel tastings, good results are obtained with a costing having a base of very Sne silica: for cuprous alloys, a coating of silica and also one having a base of ocher are used; a coating composed of graphite, ocher or clay, and talc is used for general pur poses. 11-Ha- _ d -- * (vol. ^1. Calculated imlices-show close agreement with experimental values. The decomposition, purification, and preservation of methylene iodide i* fii*cu**ed. 17 references. 1 figure. W.D.P. Msatil hygiene sad isdusstoi health. R. O. Xovtck. V,ul. 2fafttj ,\'rwt, 36 [til 23-29. 33-84 1947)__ Emo- tiouai factors in the adjustment of aa employee to hi* work are beginning to be recognized as aa impoitant factor in ,-ufecy. W.A. Method* of sterilization of protective equipment. Wautsr F. SchouZ. .1 in. fud. fiy{. .1ssn. Qtuiti.. I -4 92 (19471.--A liquid soap solution i* used, followed by stream of warm water to remove the soup. The Uuiniec- taut Rocal i* then u*<d after diluting d os. with 6 gal. of water; the bath i* used for a week. At one plant about 73 respirators, 3U0 goggles. Uhl goggle cases. 12 rubber suits. 5 rubber boot*, and (35 miscellaneous piece* ate sterilized in one week. Time of immersion in the bath is U) min. Dtopped-caissos shaft sinking. Witt.wit 3. Cota. J*. nt. .winter 149 141 S2-i'J (1948).--Bauxite deposits The hands are not affected by immersion in the Rocal. Zephiran chloride is also satisfactory but more expensive. ia Saline and Puiaski Counties. Ark., require many shallow v.o.r. shafts in proportion to the tonnage mined. Conventional -- Pulmonary dust disease- A. R. Rtootu.. fnd. JA-5.. shaft sinking ut not advisable duo to layers of quicksand. 17, 158-70 (1943).--Silicosis is the mot important hut y A concrete caisson was made 18 in. chick and with an inside there are other dust diseases. The status uf -aluminum * diameter of 3 ft. for a shaft. It was planned to dig out the a therapeutic agent for silicosis ha* not yet been deter- middle, drop the caisson, and put another ring of cooerete J mined. Fumes from heating bauxite to make corundum and repeat, but considerable trouble was encountered: cun cause trouble. The fume contains much alumina, however, it was finally completed to a 21M ft. depth. Fu silica, etc. Early cases are symptom-free with a slight ture projects should {1) avoid test hales closer than 20 ft.. lung shadowing. Later the symptoms may simulate O ha-e adjustable guides for aligning the shell, (27 Have pneumonia and heart disease -and the shadowing spreads. guide runners to keep the caisson aligned. (4) have a gasket Cadmium or cadmium compounds, either a* fume or dust, to stop sand blow*, and (3) use water-tight joints between cause a serious lung diaesse. During the war beryllium all poura. 4 figures. W2D.P. poisoning became known. Asbestosis has long been Factors which will influence ceramics in arr 23 years. known. Worker* in a vy dusty talc mill showed lung Anon. Crra/n. fnd.. SO [51 33 (194$).--Fifteen factors 7 damage, but the miners did. not. The talc was Sbreu* and which will influence the nest quarter century > ceramics contained 3U to oOfi free silica. There are *ome benign are a) follows: Americans will live better; there will be pneumoconioses, such -a* sidcrost*. which do not affect the more family units: the population trend is up; the avera;e length of life. 7 references. IV D-F age will be slightly older; military preparation will be __ Photoeeraaie cieimiqu*.. 3. A. BiazoS. Abstracted pUmncd is billions, commercial construction has only in 3'f*W<ioyo i Kcrtim. Pram.. 1947, No. 9, pp. 17-13.-- started; institutional and government need* involve huge Detail* -ore given for craniferring images from glas* onto construction; the European Recovery Program will tax ceramic ware. The following reagents are used: (ll (or American production: competitive raw material* are being , cleaning '.he gluts, a solution containing 4 gm. of ammo* depleted: borne and rental construction will inerr.ise: n nium dichroinate, ID gm. of dextrin, and 2:) gm. of sugar in backlogs still exist and may be mereusetl: technological l'*> ee. of water: (2) for transferring the image from the developments will broaden markets; industrial construc gloat onto the ceramic ware, a solution consisting of 3!) col tion will continue strong; competitive product develop lodion. :IU ether, and 23?i of 9H* alcohol; ill) a dark-brown ments will challenge ceramics; and labor relations will be -- color containing the pigment* FelOH)i, CO(OH)?, and mutually more enlightened. C.O.fl. ZtiO in the proportion of 2:1:1 and a black color containing Failure to block doorways of freight cars estates sever* the pigment* Fe(O.H)s. MnCOs, and COiOHl* in the pm; damage to peckaged freight Anon. Am. Faint 31. portion of 2:1:4. The rtu-c far these eolor* coni*ts [231 75-80 11948).--A mth of documentary photographs i Fb.O. 73. quartz 12.7. anti bone acid l2.ir. B-Z.IC. taken by the Shipping Container institute show freitht Report oa Britsb Industrie* Fair. Jack Brook*. damage, its causes, and the results. The value of hloekin; c.rsm. rod..;o [hi m (194a). c.o.b. doorways to prevent load shifting i* stressed, and methods Research oa ubesto* fibers. Nt. S. 3aoouuxt. T'"os. are suggested to prevent such shifting. A-J-K. C,in. Inst. Mining J/W., 31, 212-15 (1948) .--Thu /ohn Mut< v'tuit* . Klxf unpr mg: S Ta\ for werv ivhtu whil- e91: 2UV- of i uni* vryp tnpc vitrt giver and trou land tion. insul and tmel dlic abet \ * lu n 9eJ. f Carr Sr fotrr *T ** r. p 7 (194 k T: is tl X Poo aids "Pc- Tit. port. * Pott pen< V ~*.r stardeal usee i V, [81 iodu of re aa. A f i Ami 4 3th Sr rir- i give + V7 A V //.- abst ?ho indt i' m. #1 I & Brl_ :: ::90 I Pulmonary Dust Disease A. R. RIDDELL 5A, MJ. DAH. pinions concerning dusts and pulmonary considerable value in tbe estimate of disability. O disease have changed somewhat during the A review of the symptoms and signs presented last few years. For a considerable period followby 637 persons with silicosis was recently made. ing 1918 attention was chiefly centered on silica. This offered information which may be usefully Dusts were classified os active or inert according applied. The Investigation confirmed the finding u the reaction they occasioned in the lungs re that dyspnea is the commonest symptom and lim sembled or differed from that produced by silica. ited expansion the commonest sign. It also dis Although silica is still recognized as the most closed, that of 203 persons frith a history of important dust eoneeraed with dust lung in haring had night sweats, 117. or approximately jury, it has gradually become apparent chat dusts 53?*. had positive sputum. Bacilli were demon other than silica and the silicate asbestos may be strated either at the original examination, or involved la pulmonary disorders. later on followup. 1c indicated, that 70, or $054,* A description of silicosis is superfluous at of those with hemoptysis were tuberculous, and present. 'The disease has received so much atten that 134, or 75 f*. of these whose fingers were tion and has been discussed so often that you are clubbed or who had curving of the finger nails, all conversant .with its general features. You had positive sputum, or were dead when the an realize that silica dust inhalation, if the quantity alysis was made. of dust inhaled Is adequate, may result in lung It will be realized that for practical purposes, fibrosis of a special nature. Collagenous nodule diagnosis in silicosis involves the differentiation formation Js characteristic of this process, but of type as well as recognition of the disease. its regular deposition may be altered often pro Commonly this is made on the radiographie ap foundly by accompanying infectious processes, pearance a ease presents. Cases with clear cut or by admixture of the dusts of other materials uniform nodulatioa are interpreted as simple, with silica. Tfc is general knowledge that silicosis and those with conglomerate or massive shadow, la prone to association with tuberculosis, but ing as complicated. Although this may be a use the implication may not be so fully appreciated. ful working rule in relation to the interpretation The late fix. CAXDNZS1 is reported to have ad* of radiograms, there art many* exceptions to it. . vanced the opinion that, when chronic, a com >'ot infrequently the radiographically simple ease bination of silicosis with tuberculosis constituted will prove to be complicated, and no evidence of a disease quite different from either of the other an infectious process cam be demonstrated in the two contributing conditions. Certainly It is dif radiographically complicated, even at autopsy. ficult to treat. As a rule It gradually progresses Compensation complicates the silieojis prob in spite of what is attempted, and surgical mea lem. With diagnosis so dependent on the inter sures are unsatisfactory- This disease may be pretation of radiographic shadowing as is the seriously disabling, although those affected are cas* at present, it is well to remember that heavy not alwaye obviously ill. or prominent shadowing in the lung fields or The importance of tuberculosis in conjunction even nodulatioo, does not aecessarily denote fibro \ with silicosis is illustrated by information sup sis or silicosis. These appearances, eommonly plied by consideration of the causes of death in ascribed to the effects of silica, may be simulated a series of 43S. silicotics on whom we have rec by lung changes related to other conditions than ords. The persons concerned had been employed silicosis. In which there Is often no fibrosis. in virious occupations carrying a silica hazard. When coses presenting such radiographie ap ' A little more than half of them were miners. pearance lack a history of dust exposure the Pulmonary tuberculosis caused the deaths _ of situation may not b* too diCcult. but with such 62f/e of the persons comprising the whole series, a history they may cause considerable eonfusion. and was responsible for 68?<? in the mining group. TVe have found the more important of these con Estimations of disability are notoriously fusing conditions to be--heart diseases, particu troublesome in silicotics. It would seem that larly mitral stenosis, certain fungus infec these are too often based on radiographie ap tions, benign pneumoconioses, disseminated new pearances together with attempted measurements growths of the lung, and sometimes pulmonary of breathing capacity, and that other useful in tuberculosis with a miliary distribution. formation is apt to be neglected. In assessing Aluminum dust employed in the treatment of. disability the clinical picture should be viewed or os a prophylactic In silicosis, ha* received as a whole- Careful consideration of the infor much attention in this regard during the last few mation afforded by the symptomatology and clin years. It is administered in two forms, as finely ical findings in the individual cases, may be of divided metallic aluminum, and as .aluminum hy droxide. The metallic powder is the more im Ini tl is. rnfluil Tm* fir l>ovrtfUL Putpitu.h* In, X*rgh 1, ifiL of th Xt, an:*.* Hwu- portant agent, and at pre-er.t many person#, are MU*I. receiving it both here and abroad. Its admiais- 5355V,-- --- 3 <3L. tLs^. Usability, presented tly aailr. i usefully ie finding i end IIjti. also di*ustory <if odmately <* demon, ution, or >, or SO',. llouSt and gen wen* igtr nail*, at the an* purpoaw*. rentiatinr. e disease, rsphic m>* dear on ii eimpli*. dow- Ui*`* Sods to it. imple canvldencc f tted in th<* autopsy. osls prnl** tlia inter* a* is the that heavy r fields *r ytote fibr*** eommonly * siraulnlf't .itions than to fibrosis, raphic apposure the with sueh confusion" these mil 's, partivti* gus infev* mated n'w pulmonnr} ion. .atment is recciv**t 'irt *' fin*-'-:- ,ri H* .ore in;* person* n!'** ta admi'-i*- *;'V0t. 17, No. 5 INDUSTRIAL MEDICINE Pay* IS'J !*y jrstion has not been observed to be attended by -y injury. neither however, is there convincing 'i* Vdence that It haa been of objective benefit to silicotics. Nevertheless, many persons receiving, .or who Have received aluminum for silicosis claim subjective improvement. The status of aluminum as a therapeutic agtnt ^has not yet been determined. It seems to offer ""possibilities as a prophylactic, but as considerable '.Vtime is still necessary to establish its usefulness, -.Vno laxity in regard to recognized methods of dust . D&eoatrol should be countenanced. >- Early in 1942 an occupational lung disease new to this continent was discovered by PS. c. c. '^isKA'.'St, Superintendent of a sanatorium^ situjSated near St. Catherines, Ontario. A description the disease and the circumstances which re* ^yealed it haa already been published.1 The de* tails need not be repeated. In the process is* Evolving bauxite, aluminum ore is converted to '^-corundum, a hard metal used in tie abrasive In* -industry. While the process is.In operation, the rryshendant workmen are exposed to dense fumes Ilf.from the materials being treated. The process is not new. It has been carried on -.for upward of 20 years in some of the plants ^concerned, yet it was not previously known to -ri-ibe injurious. This may be explained on the &.basis, either that in the past it did sot occasion .f^lung Injury, or the disease was not recognized ^because its accompanying signs and symptoms -izLyttt ascribed to other causes. The latter is the ":&5more probable. Early cases are symptom free, irriiihe signa, exclusively radiographic, are often so ^.slight that they would be readily missed by one j^raot conversant with the situation and on the out for them. Later cases as characterized 1^'lbr attacks of sudden extreme dyspnea and chest Vc^paia which have, on occasion, been interpreted as .<jsdiesting heart disease or pneumonia. The radiographic characteristics of the eon.'rgdition may be divided Into "early" manifesta- *&Soas and "well established" disease. The early ij-Snacifestations ire extremely slight. They eon* ^jSsist of 'an indefinite granular appearance la the gy.tpiees with slight rather lace-like shadowing j^which appears in the sub-apical area and-which .v-tciv extend to the first interspace. As the eon* Edition advances the lace-like shadowing is found '-^fisteading lower in the lung fields. A further ex* .^'tension (3 accompanied by the loss of the lace*liie character of the shadowing. Eventually the ii^vhole lung field may be occupied by shadowing which has a rather granular, or even an irregular iTjhcddar appearance. *'y Coincident with the peculiar lung shadowing ilihe diaphragm is generally markedly distorted. '* sad the mediastinum is widened. The "well e- ' -blished" case is characterized by the o;cur"ty.ce of spontaneous pneumothoraces, very often - bi-lateral. There occurrences are associated with -the rather dramatic appearance of desperate '.'.dyspnea and severe chest pain. " The fume is the source of this lung damage. It contains considerable quantities of very finely (<4irided alumina and silica, and small amounts hfi of masr other substances. Which of these Is responsible has not yet been determined. In the presence of so much silica, this material can not be absolved, on the other hand rather sim ilar lung damage has been reported from Ger many* in exposures in which aluminum at least figured. xiSDtxroX'* also reported a eaae In Eng land is which exposure to aluminum was asso ciated with lung ehanges. The inhalation of eadmium dr cadmium com pounds. either as fume or dust is attended by respiratory damage of a serious nature. In an Ontario exposure 15 workmen from two plants were injured in this way in 1935--two died. Dust is produced when the metal it being ground or polished. Fumes are evolved during welding operations, or when the metal Is sub jected to high temperatures by accident, or for the purpose of removing eadmium plate. When sisal] quantities of eadmium are in* haled, dryness of the throat, eough, a sense of restriction in the ehest, headache and vomiting are produced. Heavy* exposure is followed by severe lung changes, accompanied by marked dyspnea, persistent eough. cyanosis and prostra tion, which may b prolonged. The disease has the characteristics of & ehemical pneumonia, and this Is confirmed by postmortem findings. Con valescence is apt to bo protracted, but they even tually return to work without disability. In one instance radiographs were prepared during the acute illness. In this, the lung fields were seen to be occupied by intense nodular shadowing, closely resembling that to be observed is certain eases of silicosis. Radiographic exam ination of the survivors of the affected was car ried out acme years later. In none was there evidence of any permanent lung Injury. It was during the war years that beryllium poisoning was drawn to our attention.1 Exposure to beryllium or to certain of its compounds is attended in certain individuals by skin troubles.' It is also attended'by lung disease, oftan of a serious nature. The disease has special features: Symptoms may develop during exposure, or they cay be delayed, perhaps, for month* or years after exposure has ceased. Two types' of th* disease are recognized, an acote type and a de layed. The scut* form has characteristics which suggest a ehemical pneumonitis. It results from exposure to high concentration* of beryllium compounds. It may be severe and even fatal, but is those who survive, the condition haa a tendency to clear. The delayed form appears to have little relation to intensity of exposure. It is more apt to occur where relatively light, but more prolonged exposure has been sustained.. A feature of the delayed form is the occurrences'of scattered granulomatous areas in the lung tis sue which miy undergo organization. In some ca> the radiographic appearances closely re semble rii;cn<!j. it was therefore thought at one line that the disease might be a modified sili cosis. The etiology is still obeeure. While in* vestigaiir.g this matter, it was PR. cxaoKta'S* opinion that some other factor than beryllium Pag* 170 industrial medicine 3fcy. 10SS might be involved. This Apparent!}* has not yet been established. Considerable data is being col lected and may serve to resolve the question. The dust of asbestos, a fibrous silicate, induces a lung fibrosis which may be disabling. The disease asbestosis differs considerably from sili cosis. Although areas of fibrous tissue develop throughout the lungs, these do not exhibit the nodular pattern that distinguishes that condi tion. RadiologieaUy it is also different. Charac teristically the heart shadow is shaggy, and the lung fields have a granular or "ground glass" appearance, but definite oodulatlon is sot appar ent Circulatory embarrassment is common in asbestosis. The disease however, does not appear to predispose to tuberculous infections. Aside from asbestos, silicates are not usually related to lung injury. In this respect tale, a hydrated magnesium silicate, may be an excep tion. Although no clear evidence of Injury has been produced in connection with persons hand ling tale, in many industrial operations such as tire building, paper making, etc., injury has been demonstrated in relation to the production of this substance. Some years ago in Ontario the miners and millworkers from a small talc ^pro ducing plant were surveyed. None of the miners showed radiographic changes suggesting disease, hut examination of 37 mill men engaged in crushing ore discovered 13 in whom chest films gave evidence of lung fibrosis. The exposure periods in these cases were from five to 13 years. The average exposure was 12 years. The radiographic appearances were not uni form. In some, diffuse fine granular shadowing was seen throughout the lung fields. In others, nodular shadowing resembling but rather softer in character than that of silicosis was present. Several presented a combination of these appear ances, with or without areas of massive shadow ing. Repeat examinations of many of those af fected reveals that in none haa there been any clearing, but that several have progressed. The talc, a fibrous and flaky variety containing a small quantity of tremelite, occurs In forma tion consisting largely of crystalline limestone. In this formation numerous stringers of quart* are found. In the past dust conditions in the mills were very bad, and great clouds of dust, visible from a considerable distance, could be seen escaping when crushing was in progress. Dust sampling was done in these mills. The samples varied considerably in silica content, depending on where they were co'lected. Air samples contained approximately 34 "c silica, nr a settled dust from the beams about 53lie. Thu free silica content wns estimated at 1% to 2*r. It is evident that in 1943 siCaLt and other* encountered a situation somewhat similar to this in St. Lawrence County. New York. Doubts are entertained respecting the On tario exposure. Having regard to dust condition.* and the quartz in the limestone carrying the talc, the abnormal finding* may very well reflect a silicosis modified by other dtisi. On the other hand, the matter of the extremely heavy dosage must he considered. Although several of our casts have died, w* have not so far secured autopsy material. This is essential to a solution of the problem. ' Certain lung conditions termed benign pneu moconioses. of which siderosis Is an example are not infrequently encountered. These con ditions are not in the least disabling and they do aot affect life expectancy. They arise In re lation to occupations In which dust of metals or other Inert materials are produced. Particles of these materials opaque to the roentgen rays, on reaching the lung tissues are deposited-in re lation to the lymphatics, where they remain in active causing no injury. These conditions are not properly termed dis ease. I have referred to them merely because they may occasion radiographic appearances scarcely to be distinguished from those due to silicosis. It should be remembered However, that infectious processes may occur In persons with benign pneumoconiosis. In such cases the. in fection is the disease to consider. V*oux attention has been directed to a few dusts which are involved in the production of pulmonary diseases, sod certain characteristics of the disease they occasion, have been referred to. The subject has not been exhausted how ever: The connection between bagasse, sugar cane from which the sap has been extracted, and lung disease, should not be overlooked. Neither, should it be forgotten that dusts such as arsenic tnd those of certain radioactive materials have been related to the occurrence of neo-plastic lung conditions." You will recall that cotton workers art subject to an occupations! disease, in which the materials they handle are in some way con cerned, and that cotton dust may be involved. IVe have in Ontario, plants in which the work ers are in exposure to radioactive materials. Arsenic and cotton. Most of the plants have med ical departments, and x-ray surveys of the work ing staffs have been conducted from time to time. In spite of this careful supervision however, no convincing evidence has yet been forthcoming which would indicate that any of these materials are implicated in the causation of this type of lung Injury in Ontario. Complacence, especially in regard to occupa tional dusts of any nature, is always dangerous. Also new substances are frequently being intro duced into industrial operations, and older sub stances used in new way* and combinations. The result of these changes is often unpredictable. Constant vigilance is therefore necessary. 8ib!iogr*phy I. A. J.. J. Smvm. c. r.,, ri .V.A_ :t-*fJ. ll. A. 0.: J. Vj;. f Tr_ IS--UfJ.Ut4Ti. a.tUL'*/. . <%****>* i fU* )5 I'.'T*; lVe'* Jfl't U* l*^*t* tMl* 4, iiiivtJW*.*. TL U; /**. .VV. i. Van Orwtsumi. X. 5- Xivcw. it. Ci>w. X. U.; CUrt^***d l*i? 10i (VeL 4* i.'fctibft.' T. Slft*L w. 4u:?)q, APCaIM R.. ^" j* /.Vef. f**d. il*f *