Document 10OyxEnomnzz8rKdGEyX4E7dj

/ / PM PA NV MAIL mi Mo. 2860 V. V. f Sh*pfatr4, Xiq, Tumir k HiU Lid. Spotland, Roohdal* Dur Mr. Shiphirdi dubjiot: Dr* Liroy 0. Oardar ibiito* Dust Tbank you for your lottor, TAM Mo. of May l$th on* cloilug copy of Dr. Tnncli* boIii wrlttia i tar paruaal of tba outlloi of tbi propoiod aoaogr*pb/ by Dr. ~ ' I an landing o copy of Dr. Frunolo' aotoo to to havo ` hii roply wltbln roioonoblo po^lod of tlm*, will of oourio load It oloag to Ai yit I Uv* aot rooolTid A today writing to find out rtkaji our handi. a: ok Copy by boat / .5 r\ TUB SA1UIAC LABORATOHX roa the stodx or toBUtcoDosis of tha Idnrd L. Trudeau Founds tlon flaranoo Lake, I. X. - Juno 9. 19+3 Mr. Yandlver Brown, Secretary Johns-Manvllle Corporation 22 East +0th Street iev fork. In Fork Daar Mr. BrownI X an pleased to lutadt th. following. Bofwn.li on Dr. Francis' portinont qua*Home about our .xpeMJM'hCB upon a*bto ll]. Ha la eorraot In assuming that these point] will be dliniiM In tba forthcoming publication but for hla benefit I- will amplify than at th. present tin*. .' - Th. difference* that wa haw*, observed between Bolivian and South African blua asbaatoa nay not apply generally to comrolil products, la aorkad only with anall sample* furnished ua by Prof.iaor Laraan of tha Harvard Dapartnant of Mineralogy, which b. had selected baeauaa of their purity. In these particular aanplaa tin dlffaraocaa In flbro flexibility war# wary obvious; tha Bolivian natarlal balm composed of a bundle of straight, atlff flbraa wrr 3 Inch.a lom whlla tha South African aanpla was a block of nlnaral fron which tha flbraa could ba acrapad off aa a fluffy Mia of rina flbra. In our affort to dataralna tha effect of wary pure aubatancaa wa may hava daftatod ona of our purposes, levertbeless, 1 trust that tha furthar experiment* atlll In profrass with tba lattar typa of asbaatoa nay establish tha Importance of flbra flexibility In tha production of pulmonary fibrosis. ; .Tha question of tuberculosis In association with tbejtoa la onathat has been long discussed. All observers hare bean imprasa ad altb the Tory pbvloua differ.peas In tha IncIda oca of t^li Infection In American and English .asbestos Fabricator*. I'-bar a eorra a pond ad with Dr. Marewaathar aboutthli aubjaot for many y.ari and on tha occasion of hla recent visit to this country'wa discussed the matter at graut. length. Onllka silicosis, which. Is unlwarsaliy naoclatad with an excessive IncIda me of tubareulosls, asbastosls Is apparently so oomplloatad only In certain locations. la tha United States surveys of asbestos workers have never revealed an usual fre quency of this infection. In Quebec tba rates are high but aa far as ona can lsarn thay do nut surpass tha generally high' rata for that province. In England, tba incidence of tubareulosls In asbestos fac tories Is geatrally accepted aa excessive but tha basis for belief Is largely post mortem material. I know of no-report based apon roentgan- ographlc surveys of largo groups of living em>loyeas. While autopsy ~ 0 i Als-^OO) V