204 proceedings: philosophical society 



The 524th meeting was held March 21, 1914, with President Bartsch 

 in the chair. Two new members were elected. Two communications 

 were presented: 



Arabic interpretations of the songs of birds: Paul B. Popenoe. 



Bird migration in the Mackenzie Valley (illustrated with lantern slides) : 

 Wells W. Cooke. 



D. E. Lantz, Recording Secretary. 



THE PHILOSOPHICAL SOCIETY OF WASHINGTON 



The 734th meeting was held on January 17, 1914, at the Cosmos 

 C ub, President Fischer in the chair; 29 persons present. The minutes 

 of the 730th, 731st, and 733d meetings Avere read and approved. 



Mr. H. E. Merwin presented a paper on A formula for calculaimg 

 solubility, vapor pressure, and optical dispersion. An equation of the 



type — ^ = '^ ^ + C(x2 — Xi) can be written in the form of an 



yz-Vi y3-yi 



equilateral hyperbola which does not pass through the origin. If x 

 and y represent temperature and pressure, or temperature and solu- 

 bility, or other sets of quantities that are used in graphs on rectangular 

 coordinates, interpolations may be made. Or x and y may represent two 

 temperatures at which pressures or solubilities, etc., of two substances 

 are equal, thus expressing the relation of two similar curves, and making 

 accurate interpolations possible for curves which are not readily repre- 

 sentable by equations. The form of the curve of the equation is readily 

 altered by putting C{y2 — yi) in place of C{x2 — .ti), or by writing for 



Xz — Xi /X2j-j:i\ 



the right hand member . C ^^t-xJ . Two standard solubility 



curves were described, and it was shown that many solubility curves 

 are rectangular hyperbolas. 



Mr. G. W. ViNAL presented a paper, illustrated by lantern slides, 

 On certain electrochemical problerns: (a) Reversibility of voltameter 

 reactions, (b) Purity of silver deposits, (c) Ratio of silver to iodine, {d) 

 Value of the Farady. Since the complexion theory has been disproved 

 by recent work at the Bureau of Standards, the question of reversibility 

 was again investigated. Quantitatively the results show substantial 

 agreement in loss at anode and gain at cathode. When a striated 

 anode was used no such equivalence was found. Previous work on the 

 inclusions of foreign material in the deposited silver was reviewed and 

 the contradictory nature of the results pointed out. No conclusion 

 can be drawn as to nature or amount of inclusions, but it is believed that 

 they are very small in deposits made from the purest electrolyte. In 

 striated deposits some evidence of included water was found. Compara- 

 tive experiments in which the iodine voltameter (used by Dr. S. J. 

 Bates) and the silver voltameter (porous cup and Smith forms) were 

 compared afforded a new electrolytic method of determining the ratio 

 of silver to iodine. The value 0.85017 was found, which is 22 parts 

 in 100,000 higher than the ratio of the present international atomic 



