88 ABSOLUTE ATOMIC WEIGHT. 



The se-^cnth reaction represents the so-called synthesis of 

 lead nitrate from the metal and the acid. Only Stas has 

 carried out this operation. 



His series A comprises 6 determinations. Range 14, 

 mean 71 high. 



His later series B comprises 4 determinations. Range 

 u, mean 67 high. 



Also these analytical ratios are not nearly constant with 

 non-systematic, irregular differences, but they show system- 

 atic variations with the amount of lead used. 



These systematic variations are even more marked than 

 those shown by the sulphate. In the places just cited 

 diagrams drawn to scale present this fact to the eye. 



It is absolutely impossible to make use of any such work 

 for atomic weight determination, because it does not even 

 comply with the condition insisted upon in all good analyt- 

 ical work. See pp. 53-54. 



It is in no sense our business to show how Stas came to 

 make such a mess of this work that has been so much 

 admired until we showed this fatal error which totally and 

 for ever must exclude this work of his from consideration. 



We tried, in our True Atomic Weights, to point out the 

 reason. But it seems not yet to have been understood by 

 the admirers and imitators of the work of Stas. 



In this place we state once more, that this work of Stas, 

 bearing on its face the plain systematic error (whatever its 

 cause may be) is by this simple fact necessarily excluded 

 from consideration in the determination of the atomic 

 weight of lead by every chemist who understands that the 

 amount of nitrate per gramme of metal must not system- 

 atically vary with the amount of metal employed. 



If any individual, claiming to be a chemist, or even 

 holding a professorship in chemistry and receiving a salary 

 as such from a state or an institution, fails to understand 

 this fact here stated and shown to exist in the record of Stas 

 himself, such individual eo ipso is not a chemist, is unfit for 

 such a professorship and draws the salary as an impostor. 



If he be an editor of Chemical News, he is blocking the 



