INTERNATIONAL ATOMIC WEIGHTS. 

 By Theodore William Richards. 



Received August 18, 1900. 



Near the close of the year 1897, the German Chemical Society 

 appointed a committee to select values of the atomic weights for common 

 use in Germany. The confusioD arising from the use of different values, 

 and especially of different standards of reference, had become unbearable- 

 After nearly a year's deliberation, they announced their conclusion that 

 it is expedient to call oxygen exactly 16, and to refer other elements to 

 this standard. They published a carefully considered and conservative 

 table of values,* which immediately gained wide acceptance, partly be- 

 cause of its intrinsic merits, and partly because it was vouched for by 

 such eminent men as Landolt, Ostwald, and Seubert. At the close of 

 the remarks accompanying this table, the three members of the committee 

 expressed their hope that the matter might be clinched by international 

 agreement. The hope was strengthened by the fact that the two other 

 modern tables, those of Clarke and of Richards, differed but slightly from 

 the table presented in Germany. Time has strengthened this hope still 

 further, for the two subsequent yearly editions of the three tables have 

 steadily tended toward the elimination of earlier differences, until now 

 they are even more alike than they were at first. | 



On March 30, 1899, having heen encouraged by the favorable recep- 

 tion of their work, the German committee issued to all important asso- 

 ciations interested in chemistry throughout the world a general invitation 

 to appoint delegates to an International Committee, t The number of 

 delegates was not determined, and the outcome was the appointment of 

 fifty-seven men from among the most eminent chemists of eleven nations. 

 As representatives on this International Committee the American Chem- 



* Ber. d. deutsch. chem. Gesell., 31, 3761 (1898). 



t See Journ. Am. Chem. Soc, 22, 78 (1900) ; also, These Proceedings, 35, 621 

 (1900), and Ber. d. deutsch. chem. Gesell., 33, 1 (1900). 



J Ber. d. deutsch. chem. Gesell., 31, 2949 (1898) ; 33, 1847 (1900). 



