Letters Received to H.H. Barker, November 23, 1931

UNIVERSITY OF MISSOURI COLUMBIA DEPARTMENT OF CHEMISTRY November 23, 1931. NOV 25 1931 Mr. H. H. Barker United States Radium Corporation 535 Pearl Street New York City My dear Barker: In glancing at the last letter received before the present installment of four which came to hand this morning, I find that I have allowed consid- erable time to elapse since writing you last. In ac- cordance with your request we are sending under separ- ate cover three or four copies of our paper on "Dangers in Refining Radicactive Substances". We are certainly interested in the pro- posed experiments on the determination of radioacti- vity of subjects in the Elgin Hospital. I may say that immediately upon receiving your first letter on this topic I set Mr. Paul Morris at work to extend his methods of testing for radioactivity ir living persons. He is now perfecting a method of determin- ing quantitatively the radium emanation in expired air by condensing the emanation in liquid air on the one hand and on the other in absorbing the emanation in activated charcoal. In other words, we are elabor- ating the tests for radicactivity in living persons and we hope that in time all this technique may serve in such problems as the one which we will have at Elgin. I have been unusually occupied this fall and thus have been unable to suggest any date at which we could undertake such measuroments. The Christmas Holidays are probably not very desirable dates, but that will likely be about the only tine I shall have free. Now, with regard to the progress on the refining of radium, I shall defer that for this moment until I have had a good talk not only with Breckenridge but also with Carroll. I asked about the progress the other day and they informed me that one of the shipments