a 7 ResSHALL: (contimsed) nae in the pioture, or the more widespread feedstuffs. After « iittle calculation, 4f it turns out that esy a hundred grans or so of bone material, were enough to allow you to take a messurement with a guess of a hundred dollara for the enalyais of this particular sample, one, I think, eotld in this comtry -~ the esloulaticn I did for ten cities assuing that one takes account of various age groups, start say with an age group ef from 0 to 5, 5 to 10, 10 te 15, 15 te 2, and 2 and over, perhaps, that ene aight take three samples in each age group totaling 300 grams, randemly sort the pieces inte 300 gram units, analyse cach one, and get his count. This is all for ene city, and for the various age groups, end get an idea of how the fallout in the eres and the countrywide averages related to the amount of Sr” in uman bones of the funotion ef age, frou the past experieness, Fron this, one might be able to try scme predictions, depending upon how variable one found it and one needs, I think, in each one of these areas, at least two detaruinations at ench age group, for the purpose of getting an idea of the variations even for iets within a particular ares. LIBEY : Take a AGLW/, te case of the human sewage of Milwaukea.. - You've certainly got en enormous averaging already in the sanpihg. MARSHALL: Yes. LIBBY; How, what would yon do in addition in order to get the variability paremetar? You cartainly have in that, a pretty fair average for MENEEEINEEEP food and 20 on for the city of Milwukes. DUE ARCHIVES