THE CHALLENGE OF STAS. 173 



Neither his challenge of 1865, nor its i( Renouvelation " 

 in 1881, has ever been taken up. At least, no chemist has 

 taken the trouble to repeat this work of Stas. 



I venture to say that no chemist ever will repeat it. 



The challenge is not a demand to disprove the value 

 N= 14.04 claimed to be true; for that value has been 

 demonstrated to be false, at least by myself in my True 

 Atomic Weights of 1894. Some of the most eminent chem- 

 ists of the time have admitted this, my demonstration, to be 

 final. Here I may only mention the work of Schiitzenberger 

 in the Actualites of 1896 already referred to, and in his 

 posthumous General Chemistry, Paris, 1898, pp. 143-152. 



That the method of procedure of Stas cannot give true 

 values has also been pointed out by Schiitzenberger on the 

 ground of his own experiments; see close of his paper, 

 Actuality's, Paris, 1896, p. 16. 



We shall here once more prove it, this time by Stas him- 

 self, that his method of determining the atomic weight of 

 nitrogen by his so-called syntheses of silver nitrate is a most 

 remarkable mixture of chemical folly and error, or rather 

 fraud. 



Let us take the weighings of Stas as published by himself, 

 and as so frequently republished by his numerous Re-Calcu- 

 lators (see Footnote, p. 75), all fully represented in my 

 " True Atomic Weights,'* 1894, from page 40 to 69. 



Let us plot the results of Stas for the atomic weight of 

 nitrogen as ordinates to the amount of silver used as abscisses. 



We get in this way, tivo curves, one for the dried silver 

 nitrate, the other for the fused silver nitrate, and accordingly 

 two entire SERIES of different atomic weights, really an 

 infinite number of atomic weights of nitrogen, in two great 

 sets, the larger for the dried, and the smaller for the fused 

 silver nitrate. See Plate III, facing page 161 of my True 

 Atomic Weights, 1894, constructed from data printed on 

 page 164. 



On account of the great importance of this subject, I 

 will here give a brief summary of the essential data of Stas, 

 and present a new drawing carried to 600 grammes and free 



