Letters Sent to Dr. Frederick B. Flinn, April 14, 1926

COPY WILLIAM L. CLARK, M.D. 2215 Walnut Street, Phila. , Pa. April 14,1926. Dr. Frederick B. Flinn, Professor Industrial Hygiene, New York City. N.X. Dear Doctor Flinn: I returned a few days ago after spending the winter in Florida convalescing from illness. I did not take care of correspondence while there which accounts for my failure to reply to your letter dated January 26th. Replying to your question regarding the character of bone ne- crosis folldwing the use of radium salts and emanation. I have not observed that this necrosis differs materially from that following the use of any other agent that would cause bone disintegration. I especially speak of caustics, and his frequency currents, and such diseases as taberculosis or lues. Radium necrosis of bone may not occur for a period of months, or even years, after exposure to radium. Hence the necessity of using great care in its application. Porosity is first noted, gradually developing into complete disintegration and sequestration. This phenomenon has been determined by x-ray studies. The dentist with whom you conferred is probably right in his observations, but I believe that the gelantinous nature of the bone was caused by bacterial invasion and continued maceration by secretions in the mouth. We are constantly removing disintegrated bone in patients that have been treated by radium, which dondition is entirely independent of carcinoma, and was caused entirely by radium. If there is any way that I can assist you in yor studies please call upon me. I regret that conditions were such that I could not report to you before. With kind regards, I am Sincerely yours, (signed) W.L. Clark. P.S. I have directed that a reprint on objections to Radium Emanation in bare Tubes be sent you, from which you may glean some information.