2. Sampling methods should be improved to preclude missing parts of the rain sample. 4 3. Provision should be made to assaytotal fallout at the sites of rainfall measurements. REFERENCES AND NOTES . Instructions for Operation of Air Force Rain Gauges (AF-1210). . Ina considerable number of sample aliquots, miscellaneous debris and insoluble oils were present. In these cases the samples were filtered and the residue discarded priorto analysis. . Official Weather Bureau data were used to correct the Air Force total sample volume data at the suggestion of Dr. Christian Junge of AFCRC and Mr. F. I. Sullivan of Skinner and SoavAaAu Sherman. This was to compensate for portions of the sample missed when the collector was not opened in timeto collect all the rain. In addition to the normal rain water sampling, another series of collections was run at West Newton, Mass., with the collector open at all times. No consistent relation between the two sets of data was found at HASL, however, and both results were used in this report as the best approximation of activity levels at that station. Hallden and Harley, HASL Laboratory Report 56-9. J. Harley et al., USAEC Report NYO-4862. HASL Fallout Summary, March through July 1956. Appreciation is expressed to the HASL staff members who were associated directly and indirectly with this project. Among them were Helen W. Keller and Seymour Tarras, who helped in various phases of the analytical procedures. ABST mate) const chang the c: produ pot nm may later invol isotc eval The tive] time may This mor site isc of a 354