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. 



FHYSICS.—The general character of specific heats at high temperatures. 

 Walter P. White. Proc. Nat. Acad. 801.4:343-346. Novem- 

 ber, 1918. 



The specific heats of three forms of silica and two silicates (alkali 

 feldspars), determined for temperatures up to 1300°, indicate that the 

 atomic heats at constant volume for the substances increase above the 

 theoretical value 5.96, as the heats of metals have been known to do, 

 and hence that such increase is a very general phenomenon, as has 

 been suspected. W. P. W. 



PHYSICS. — Calorimetric lag. Walter P. White. Journ, Amer. Chem. 

 Soc. 40: 1858-1872. December, 1918. 



The lag effects of bodies external to calorimeters, although more 

 complicated in expression, are found to follow the same general laws 

 as the simpler lag effects already described. More carefully stated 

 than previously, these effects prove to be three: (i) equivalent to the 

 heat capacity of the calorimeter; this can be eliminated if a calorimeter 

 is directly calibrated; (2) much smaller, depending on the amount of 

 thermal leakage; this can be avoided, if necessary, by using the adia- 

 batic method; (3) dependent on the jacket temperature, which disap- 

 pears for constant jacket temperature; this one causes the calorimeter 

 to have a different effective heat capacity when used adiabatically. 



W. P. W. 



INORGANIC CHEMISTRY.— r/i^ ternary system MgO-AWzSiOi. 

 G. A. Rankin and H. E. Merwin. Amer. Journ. Sci. 45: 301-325. 

 April, 191 8. 



The temperature-concentration relations of the various crystalline 

 phases in equilibrium with liquid in the ternary system MgO-Al203- 

 Si02 have been investigated, and are represented by diagrams and a 

 model. A ternary compound, 2Mg0.2Al203.5Si02, unstable at its 



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