0018933 fallout from the barge shots Flathead and Navajo was much less and variations in abundance were not greater than a factor of twe (Reference 54). Analytical data on cleud samples from these four events corroborated the fallout results (References 50 and 51), Some radiochemical analyses have been performed on particles of different sizes from certain balloon shots (Reference 52). In Boltzmann of Operation PLUMBBOB, both the Sr®?; mo?” and Sr?9; Mo’? raties were a facter of two greater in 22 micron particles than in 137-micron particles. Enrichment of sr89 was also found in two other balloon shots, Hood and Wilsong . 1.2.8 Fractionation Effects (II): Relations among the R-Values_ for Several Radionuclides, As noted above, some scattered observations on fractionation were reported from the earlier tests, but it was not until Operation REDWINGthat enough data becameavailable to investigate the separation of various nuclides from one another in any detail, At event Tewa of this operation, six particle samples were collected from different locations in the cloud and subsequently analyzed for around thirty nuclides, From this work, relations among the R-values for the products became apparent which seem to be of significance for understanding the fallout formation process (Reference 55), The R-values for the substances studied (mormalized to give unit intercept on the axis of ordinates) were plotted 32 a