PEOCEEDINGS: GEOLOGICAL SOCIETY 29 



ever, in the urine, but in combination as glycuronate. It can be sepa- 

 rated therefrom by steam distillation from sulfuric acid solution, fol- 

 lowed by an alkaline solution containing certain salts which hold back 

 substances which might interfere with the subsequent bromine titration. 

 Experiments on dogs showed that the thymol excretion ends before 15 

 hours, but only about one half of the original thymol can be found by 

 the analyses. The remainder may escape in part through the lungs; 

 part of the loss may also be due to the first sulfuric acid distillation. 



Discussion: Lubs inquired whether the glycuronate could be sepa- 

 rated from urine directly and afterwards decomposed. Alsberg sug- 

 gested that part of the thymol might be eliminated either in the 

 form of a decomposition product or as some other compound than the 

 glycuronate, and might not afterwards appear as thymol. Seidell 

 stated that the glycuronate is a very stable compound, and doubted 

 whether any other compound was formed. Alsberg also inquired 

 whether the product obtained and titrated might not be a derivative 

 and not thymol itself. Seidell replied that all the properties indicated 

 thymol and not a derivative. Studies of the excretion of phenol sug- 

 gest by analogy that the explanations advanced are correct. Menge 

 inquired what confirmatory tests had been made on the recovered 

 thymol; Seidell stated that no specific chemical tests were made, but 

 that dependence was placed upon its characteristic odor and physical 

 properties. 



Robert B. Sosman, Secretary. 



THE GEOLOGICAL SOCIETY OF WASHINGTON 



The 286th meeting was held in the lecture room of the Cosmos Club, 

 November 11, 1914. 



Informal communications : 



Clarence N. Fenner on Babingtonite from Passaic County, New 

 Jersey (See this Journal 4: 552-558, 1914). 



F. C. Schrader: Mountain leather from Rawhide, Nevada. 



T. Wayland Vaughan: Tectonic features of certain volcanic islands 

 in the West Indies. 



Regular program : 



N. L. Bowen: The iynportance of crystallization in the differentiation 

 of igneous rocks. Some experiments were described in which the sinldng 

 of olivine and pyroxene crystals was obtained in certain artificial silicate 

 melts. The importance of this process as a means of differentiation of 

 igneous rocks was pointed out. The results were discussed especially 

 in connection with the Palisade diabase still of New Jersey. Reasons 

 were given for considering Prof. J. Volney Lewis correct in his explana- 

 tion of the olivine-diabase ledge and also the general richness in heavier 

 minerals toward the base as due to the sinking of crystals. 



Willis T. Lee : Relation of cretaceous formations to the Rocky Moun- 

 tains. This paper is a continuation of one presented a year ago under the 

 title, Use of physiography in the study of Rocky Moimtain stratigraphy, 



