ABSTRACTS 



Authors of scientific papers are requested to see that abstracts, preferably 

 prepared and signed by themselves, are forwarded promptly to the editors. 

 The abstracts should conform in length and general style to those appearing in 

 this issue. 



PHYSICS. — The conditions of calorimeiric precision. Walter P. 

 White. Journ. Amer. Chem. Soc. 40: 1872-1887. December, 

 1918. 



In a calibrated calorimeter practically all the errors come in tem- 

 perature measurement, and the most, though often not the greatest 

 of these come in the "cooling correction," that is, the determination 

 of the effect of the thermal leakage between calorimeter and environ- 

 ment. This thermal leakage is analyzed into its factors. R. B. S. 



INORGANIC CHEMISTRY.— r/te place of manganese in the periodic 

 system. F. Russell v. Bichowsky. Journ. Amer. Chem. Soc. 40: 

 1040-1046. July, 1918. 



The older arguments placing manganese in the seventh group of 

 the periodic system {i. e., giving manganese a normal valence of 7) now 

 appear open to question. On the other hand there are 12 different 

 lines of argument based on purely chemical relationships which indi- 

 cate its position in the eighth group. This conclusion is also in accord 

 with the more decisive reasoning based on atom color presented in 

 a previous paper. An improved form of the periodic table, showing 

 the relations of the eighth and rare earth groups to the rest of the 

 periodic system, is presented. F. R. B. 



INORGANIC CHEMISTRY.— r/i^ melting points of cristohalite and 

 tridymite. J. B. Ferguson and H. E. Merwin. Amer. Journ. 

 Sci. 46: 417-426. August, 1918. 



The melting point of cristobaHte has been redetermined and found 

 to be 1 7 10 =•= 10° C. This value is consistent with the experimental 

 evidence which was obtained in a study of a portion of the ternary 



103 



