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T H E O D O R E W. R I C H A R D S A N D J. H O W A R D M A T H I . : W S .
tlie recalculated result may be considered as superseded by my later and more careful work. Because the probable errors of all of the other determinations are more than five times as great 21s those of Morley and myself. they would be excluded by the third principle proposed. The final value, if calculated from these two results, is 1.00775, I t is interesting to notice the relation between the real errors of the various lralues (assuming this value as true) and the probable errors. Only in those cases wlacre we now know tkut thcw were scrio7r.c constant PYrors, is the real error more than six times the probable error. Norley calculates a value corresponding to I .oo762 from his determinations of the densities of the gases and their combining \Tolumes. This \value has not been considerrd liere, partly because the probable error of the density of hydrogen is about 3 in ~oo.oo'),instead of 2 for the chemical method, but chiefly because of the uncertainty of the ratio of the combining volumes.' If a value is calculated by I'rofcssoi- Clarke's method, weighting each result in inverse proportion to its probable c'rror, only Leiscr's older value and my own original value would affect the valuc which I h a w sclected by more than about one part in ioo,ooo. Keiscr's older value would, however, reduce it by about 40 parts and i n y own original value by about 4 parts in ~oo,ooo. UNIVERSITYO F I L L I N O I S . U R ~ A S A1r.L. , .. .~ ..
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THE RELATION BETWEEN COMPRESSIBILITY, SURFACE TENSION AND OTHER PROPERTIES OF MATERIAL. (PI~I.:LIMIX.\RY IJAI%I
