OUR METHOD OF DETERMINATION". 63 



We may even omit the Extr. without causing any 

 confusion. 



Determination by Sight. 



In this manner it becomes a simple matter of inspection 

 to ascertain hoiv closely the actual experimental determina- 

 tions, expressed in the analytical ratios, approach to the 

 atomic ratio, calculated from the standard atomic weights. 



If the observed ratios differ more among themselves than 

 from the atomic ratio, then the atomic ratio expresses the 

 facts observed within the limit of actual determinations. 



In this way we shall find whether or not the standard 

 atomic weights are the true atomic weights. 



If the analytical ratios, the only direct expression of the 

 observed facts, agree within the limit of accuracy obtained 

 with the atomic ratio, then the true and the standard atomic 

 weights are necessarily the same within the limit of accu- 

 racy obtained by the actual experimental determinations 

 made. 



// is in this simple matter of fact manner that tue are notv 

 able to test all the atomic weight determinations made during 

 the entire nineteenth century. 



Order of Procedure. 



We shall first consider the most important of all elements, 

 and mainly the work of the old master, Berzelius, and his 

 school, in which no fancy method of work was tolerated, 

 and when simple appliances in skillful hands, directed by 

 clear heads gave results that still challenge admiration. 



Having become versed in this work and acquired 

 confidence in this method, we shall next apply it to the 

 determinations of the atomic weight of boron made in the 

 best Laboratories of London and Paris, by or under the 

 immediate direction of the most famous operating chemists 

 of the present, namely, by Ramsay and by Moissan. The 

 work of the latter has been endorsed by the Academy of 

 Sciences of Paris. 



We shall then be able to settle the question of the true 



