Document 1k9QvnL8V6RNGo2X5qevb2Od

June 15, 1953 Dr. P* G. Shipley Johna Hopkins Hospital Baltimore* Maryland Dear Dr. Shipley: One of my associates, Mr* Cholak, who is working on quantitative specfcographic estimations of lead, is very much interested in the work which von and your associates have reported in your article ''The Spectrograph!c Detection of Lead in the Blood as an aid to the Clinical Diagnosis of Plimbism*' in the Bulletin of Johns Hopkins Hospital for Hovember 1932. He is especially interested in the fact that your controls gave either negative results or questionable traces' of lead* Would you be kind enough to let us know what line or lines you have been using in the detection of lead. Various lines are reported in the literature as for Instance -h 3683*5 uid L>.Q5?*8 are reported as being the most sensitive. At present we are using- 2833*2 and we have also mad use of 2853*2* With the latter we have been able to detect 0.016 milligrams in a hundred c.cs. of blood, using 0,1 c.c. in tho negative crater. Our own work is now In the preliminary stages and 1 am asking, therefore, for the purpose of obtaining Information since we hope to profit by the experience of other workers In this field. Allow me to thank you In advance for your courtesy. Cordially yours, RAV;IS K't' 0020111