164 ABSOLUTE ATOMIC WEIGHT. 



by our own Huntington and by the famed manufacturer of 

 Tanagra Atomic Weights at Harvard University, as con- 

 trasted with those of Stas on bromine : 



" In this case again, as in so many others, Stas' work 

 (e alone appears at the end, the remaining data having 

 ' only corroborative value." 



The exclusion of the above chemists in favor of Stas, is 

 simply due to the fact that Stas kept his u probable error " 

 down to 6 in the fourth place of Clarke, while the other 

 chemists above named had allowed their " probable errors" 

 to run up from 30 to 70. 



But since these lf probable errors " are from 5 to 12 times 

 as large as those of Stas, the weight or the reliability of the 

 results of Stas, will be from 5 X 5 = 2 5 to 12 X I2 = *44 

 times as high as that of the other chemists in the Pickwick- 

 ian Sense of Clarke. 



But for these other chemists to count for anything in 

 competition with Stas, they would have had to produce from 

 25 to 150 times as many determinations as were furnished 

 by Stas. 



Since they did not, they were cooly a dropped " out ll at 

 the end." 



Now, why did not Clarke in the case of the atomic 

 weight of Nitrogen above quoted (p. 160) " drop out Stas 

 at that end?" 



Why did not Clarke Drop Stas at the End? 



And why insist on the excellence of Stas, when de facto 

 the atomic weight of nitrogen proclaimed in the Smithsonian 

 Pickwick of 1882, was not based upon Stas being excluded 

 on account of the four times greater probable error but 

 upon the density determination of what then was supposed 

 to have been pure nitrogen? 



And as the density determination was the most reliable, 

 giving the smallest probable error, why was it discarded 

 when found to be vitiated by a big- constant error, which 

 affected it notwithstanding its deliciously minute probable 

 error ? 



