52 Chemistry and Physics 



No. 267. SMITH, EDGAR R, and W. K. VAN HAAGEN. The Atomic Weights of 

 Boron and Fluorine. Octavo, in+65 pages. Published 1918. Price $1.00. 



This paper describes means for the complete dehydration of borax and its use 

 in the determination of the atomic weight of boron. The details are numerous 

 and have been worked out with extreme care and patience. The ratios are estab- 

 lished between B:C1, B:S, B:C, B:N and C. Incidentally, the ratio between B :F 

 is found and the atomic weight of fluorine deduced, and discovered to be in accord 

 with the value deduced from the ratio C1:F. 



There appears also a review of the earlier experimental work upon the atomic 

 weight of boron in which it is plainly shown why the usually accepted value 

 (B = ll) is probably too high. 



