CHEMISTRY. 285 



temperature have been continued by ]Mr. R. D. Mailey; and the 

 experimental work is so far advanced that it will doubtless be com- 

 pleted during the coming year. An analogous investigation on the 

 thermodynamic constants of ammonia has been in progress in this 

 laboratory' for several years under the direction of Dr. F. G. Keyes. 

 The experimental work, which involved measurements of the vapor- 

 pressure, specific volume, compressibility, and specific heat-capacity, 

 has now been completed and an article describing it is being prepared 

 for publication. An important practical result of this investigation 

 is that it will make it possible to prepare an accurate set of "ammonia 

 tables," corresponding to the ''steam tables" used by engineers, thus 

 furnishing data much needed in the operation of refrigeration-plants. 

 Such ammonia tables are now being computed in this laboratory. 



Under the immediate direction of Professor A. A. Noyes, investiga- 

 tions have been carried out on the equilibrium-relations of certain im- 

 portant oxidizing and reducing agents in aqueous solutions, namely, 

 of the equilibria between metallic tin and stannous chloride by Mr. 

 E. E. Corbett, between stannous and stannic chloride by Mr. W. J. 

 Winninghoff, and between metallic strontium and strontium salts by 

 ]Mr. C. L. Burdick. The purpose of these investigations is to deter- 

 mine values of the oxidation-potentials which will make more com- 

 plete the electromotive series of the metallic elements and enable the 

 important dissolved oxidizing agents to be included in it. 



Richards, Theodore W., Harvard University-, Cambridge, Massachusetts. 

 Grant No. 849, allotted December 13 J 1912. The determination of 

 atomic weights and other fundamental physico-chemical constants. (For 

 previous reports see Year Books Nos. 2-11.) $3,000 



During the past winter the Wolcott Gibbs Memorial Laboratory 

 for Research in Physical and Inorganic Chemistry was finished and 

 became available for work. Accordingly the apparatus previously 

 purchased by this and preceding grants was removed to the new 

 building early in January and work was begun there at once. The 

 time lost during the removal was more than made up by the greater 

 efficiency and adequacy of the new building. The investigations 

 may be divided into seven sections. 



(1) The atomic iceight of carbon: 



This fundamental datum was studied with the assistance of 

 Charles R. Hoover, in a new wsiy. Sodium carbonate prepared in a 

 state of great purity b}' several processes was fused in a stream of 

 carbon dioxide, and then neutralized by weighed portions of a stan- 

 dard solution of hydrobromic acid. Other weighed portions of this 

 solution were precipitated with the purest silver, weighing both the 

 metal and its bromide. Thus the equivalence between sodium car- 

 bonate on the one hand and silver or its bromide on the other hand 



