Report, November 12, 1925

Reos Noy 13 Report of the Examination of the Carcuss of Animals Treated with Activated Zine Sulphide. There were seven specimens submitted, two of which were blanks, designated as 1 and 2, that is, they represented animals which had not been treated with the active zine sulphide. The tests were nade by alpha ray comparison, using the utmost of caution to minimize any possible errors. The test 18 considered very sensitive for the detection of radio-active material. The following table gives the observations as nade in detail. Material Scale div. read. Time. 1 2 average. Blank 1 60-50 197 sec 197 sec 197 sec A 60-50 194 11 188 " 191 n B 60-50 195 " 200 n 197.5 sec Blank 2 60-50 199 " 195 " 193 sec C 60-50 194 " 195 " 194.5 sec D 60-50 194 " 196 11 195 see B 60-50 198 B 198 11 198 n Blank 1 60-50 198 11 197 " 197.5 sec A 60-50 191 " 192 " 191.5 " From an analysis of the data I think we may definitely say that samples B and E show nothing. In the case of sample C and D there may be a slight indication of the presence of radio-active material, although the difference in time required for a definite drop in potential is so small, that it may be attributed to experimental error. In the case of sample A, which was observed at two different times, there is apparently 8 small amount of radio-active material present. H. H. Barker. Novemmber 12, 1925.