222 



REPORTS ON INVESTIGATIONS AND PROJECTS. 



With the cooperation of Dr. K. G. Falk, the work of preparing a summary 

 and critical discussion of existing data on the properties of salt solutions in 

 relation to the ionic theory has been continued. Two papers — one on mol- 

 numbers derived from freezing-point lowering, and one on electrical trans- 

 ference numbers — have already been published; and a third one, on the 

 electrical conductance of solutions, is ready for publication. 



A research on the conductance and ionization of two salts of high-valence 

 types (namely, of the uniquadrivalent and of the uniquinquivalent type) has 

 been completed with the assistance of Mr. R. H. Lombard. The principles 

 in regard to ionization referred to in earlier reports are shown by the investi- 

 gation to be applicable to salts of these higher types. 



An investigation of the electromotive force of concentration-cells of the 

 form Hg, HgoSO^, K^SO^ sol. of cone. C„ K^SO, sol. of cone. Co, Hg^SO,, 

 Hg has been carried on by Dr. W. C. Bray and Mr. P. V. Farragher with the 

 view of determining the activity of the bivalent ion by an independent method. 

 The results already obtained confirm the conclusion that such bivalent ions 

 exert a very abnormal influence. 



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

 Grants Nos. 570, 626, and 707. The exact determination of atomic 

 zveights and other fundamental physico-chemical constants. (For previ- 

 ous reports see Year Books Nos. 2-9.) Each grant, $2,500 



A number of investigations were carried on at the Chemical Laboratory of 

 Harvard College with the aid of these grants, as follows : 



(i) Compressibilities and Surface Tensions: 



Dr. C. L. Speyers assisted in continuing the work on the compressibilities 

 and surface tensions of organic substances, and obtained many interesting 

 results. The data are far too numerous for detailed statement here, but the 

 following table, containing a few typical figures, is so suggestive that it is 

 worthy of presentation. The substances employed were all of a high degree 

 of purity. 



Properties of the xylenes. 



Note.— The compressibilities are in terms of kg. /cm., over the range 100 to 500 atmospheres. 



It will be observed that these properties all vary in such a sense that the 

 substance with higher boiling-point possesses greater density and surface 

 tension, as well as less compressibility. These relations, which appear to hold 

 in about 80 per cent of the cases thus far studied, are in accord with the 

 theory of compressible atoms. The Faraday Lecture of June 191 1 contains a 



