PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



THE WASHINGTON ACADEMY OF SCIENCES 



The 112th meeting of the Washington Academy of Sciences was 

 held in the Auditorium of the New National Museum, Thursday eve- 

 ning, May 11, 1916, with President L. O. Howard in the chair and a 

 large audience present. 



Dr. Ekwin F. Smith, Chief of the Laboratory of Plant Pathology, 

 Bureau of Plant Industry, delivered an illustrated lecture on Resem- 

 blances between crown gall in plants and human cancer. The speaker 

 reviewed the objections that have been raised to the theory that can- 

 cer is of bacterial origin, and showed that such objections do not rest 

 upon a sound experimental basis. He then developed the striking 

 parallelism which exists between human cancer and crown-gall in 

 plants, the latter being of unquestioned bacterial origin and readily 

 developed by inoculation with pure cultures. 



The address has been published in Science (New Series, 43: 871-889. 

 June 23, 1916) under the title, Further evidence that crown gall of plants 



W. J. Humphreys, Recording Secretary. 



THE GEOLOGICAL SOCIETY OF WASHINGTON 



The 309th meeting of the Society was held in the lecture room of the 

 Cosmos Club on April 26, 1916. 



REGULAR PROGRAM 



K. F. Kellerman: Bacteria as agents in the precipitation of calcium 

 carbonate. Precipitation of calcium carbonate from solutions of cal- 

 cium sulphate, calcium acetate, and artificial sea water by bacteria. 

 Formation of spherulites. (Illustrated.) No abstract. 



John Johnston : Some factors which influence the deposition of calcium 

 carbonate. By means of the solubility-product constant of calcite we 

 are enabled to calculate its solubility under various conditions; whence 

 it appears that this solubility is affected materially by variations of the 

 temperature and of concentration of free CO2 in the water which may 

 well occur in nature. For example, a change in the proportion of CO2 

 in the air from 3.2 to 3.0 parts per 10000, or a rise of temperature of 

 2°C, would result ultimately in the precipitation of about 2 grams 

 CaC03 from each cubic metre of a solution saturated with it. Conse- 

 quently, since the warmer portions of the ocean are substantially satu- 



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