Thies system has a background of about 50 counts per minute and an efficiency of approximately 38 per cent based on p32, The counts for biological samples were converted to disinte- grations per minute per gram (d/m/g) of wet tissue and the counts for samples of island soil and beach sand were converted to d/m/g of dry material at time of counting by applying correction factors for sample weight, counter efficiency, and self-absorption. The values for gross beta activity in the appendix tables are given in d/m/g plus or minus the 95 per cent counting error, which was obtained from nomographs based on the ratio of the counting rate and total time of counting of the sample to the counting rate and total time of counting of background (Kinsman, 1957). tables, however, Tables 2 and 3, The values in the summary have been calculated in terms of micromicrocuries per gram (yjc/g) of wet tissue. The samples collected in 1958 were analyzed for gamma- emitting isotopes with a 3 x 3-inch sodium iodide crystal DOE ARCHIVES connected to a Radiation Counter Laboratory 256<-channel analyzer. The radioisotopes present in the samples were identi- fied by their gamma energies and for some of the samples the amount of each radioisotope was determined by a subtractive