PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



WASHINGTON ACADEMY OF SCIENCES 



A special meeting of the Board of Managers was held on Jul}^ 15, 

 1918. Resolutions were passed urging the War Industries Board and 

 all other authorities concerned to grant unrestricted supplies of ma- 

 terials and labor to the publishers of scientific periodicals, in order 

 that this country shall not fall behind its Allies or the enemy con- 

 tries in this phase of the encouragement of scientific research. 



The following persons have become members of the Academy since 

 June : 



Mr. James Madison Hill, 2nd, U. S. Geological Survey, Washing- 

 ton, D. C. 



Dr. Robert Tracy Jackson, Peterboro, New Hampshire. 



Mr. Frank J. Katz, U. S. Geological Survey, Washington, D. C. 



Captain Albert Prescott Matthews, University of Chicago, Chi- 

 cago, 111.; and Quartermaster's Office, Headquarters of Central Depart- 

 partment, Chicago, 111. 



Mr. H. D. Miser, U. S. Geological Survey, Washington, D. C. 



Mr. Ralph Walter Stone, U. S. Geological Survey, Washington, 

 D. C. 



Lieut. David L. Wester, National Research Council, 1023 Six- 

 teenth Street, Washington, D. C. 



Robert B. Sosman, Corresponding Secretary. 



PHILOSOPHICAL SOCIETY OF WASHINGTON 



The 806th meeting of the Society was held at the Cosmos Club, 

 April 27, 1918. Vice-President Sosman iri the chair; 49 persons pres- 

 ent. The minutes of the 805th meeting were read in abstract and 

 approved. 



The first paper on Fog and cloud was presented by W. J. Humphreys. 

 This paper was illustrated by lantern slides. 



The deposition of dew and the sweating of ice pitchers are familiar 

 examples of the condensation of atmospheric moisture on relatively 

 cold objects. In exactly the same way condensation takes place on 

 the innumerable dust motes and other nuclei in the atmosphere when- 

 ever by expansion or otherwise it is cooled to a temperature below the 

 dewpoint. 



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