July 8, 1910] 



SCIENCE 



61 



graph line and for Kennan's actual route have 

 been interchanged. Wii. H. Dall 



SOCIETIES AND ACADEMIES 



THE CHEMICAL SOCIETY OF WASHINGTON 



A SPECIAL meeting of the society was held on 

 Saturday evening, May 21, at the Johns Hopkins 

 University. Vice-president Skinner called the 

 meeting to order and asked Professor Acree to 

 preside. After a few words of welcome from 

 President Ira Remsen, the following papers were 

 presented : 

 Temperature Coefficients of Osnwtic Pressure: 



Professor H. N. Moese. 



The report was upon the work of the last two 

 years, during which the temperature coefficient of 

 osmotic pressure has been under investigation. 

 It was shown that in the case of cane sugar solu- 

 tions ranging in concentration from 0.1 to 1.0 

 weight-normal — the ratio of osmotic pressure to 

 calculated gas pressure is constant for any given 

 concentration of solution, between 0° and 25°. 

 In other words, that within tliese limits of con- 

 centration and temperature the osmotic pressure 

 of cane sugar solutions obeys the law of Gay- 

 Lussae for gases. 



Tlie Relation letiveen Commerce and Scientific 



and Technical Work: Dr. H. F. Bakee. 

 Recent Work on the- Absorption Spectra of Solu- 

 tions: Dr. W. W. Strong. 



The absorption spectra of uranyl salts in solu- 

 tion consists of a series of about ten bands run- 

 ning from X.5000 to X3200. Uranous salts have 

 an entirely different absorption spectra, including 

 bands in the red, yellow and green. It is quite 

 difficult in some cases to obtain the uranous solu- 

 tions entirely free of the uranyl salts, so that the 

 uranyl bands will appear in the absorption spec- 

 tra. But by adding hydrogen peroxide and photo- 

 graphing the absorption spectra as the uranous 

 salt is gradually oxidized to the uranyl salt, it is 

 quite easy to differentiate between the uranyl and 

 uranous bands. 



It has been found that the absorption spectra 

 in different solvents are very different. As the 

 solvent is gradually changed the uranous bands 

 of one solvent gradually disappear while those of 

 the solvent which is increasing in amount increase 

 in intensity. The wave-lengths of these bands do 

 not change. On the other hand, when the solvent 

 is kept the same and one uranyl or uranous salt 

 is changed into another salt by the addition of 



acid, the uranyl and uranous bands in general are 

 shifted. 



Fractionation of Crude Petroleum by Diffusion 

 through Fuller's Earth: Dr. J. E. Giupin. 

 Evidence was presented in favor of the view 

 that one cause, at least, of the differences in pe- 

 troleum from different localities is due to the 

 degree and nature of the capillary filtration to 

 which they are subjected in passing from their 

 place of origin to the place where they are found. 

 After the meeting the society adjourned to the 

 Johns Hopkins Club, where a smoker was held. 

 The attendance at the meeting was sixty-two. 



J. A. LeGlebc, 



THE GEOLOGICAL SOCIETY OP WASHINGTON 



At the 231st meeting of the society, held on 

 Wednesday, April 13, 1910, the following papers 

 were read: 



Regular Program, 

 Solution and Cementation in Arid Regions: E. E. 



Free. 



Through soils and other unconsolidated surface 

 deposits there is normally a double movement of 

 water: downward percolation during or following 

 rain, and upward rise by capillarity during 

 periods of surface dryness. In the humid regions 

 the downward percolation is far in excess and the 

 various substances dissolved by the waters from 

 the soil minerals are carried away into the drain- 

 age. The soil is subjected to leaching and retains 

 no soluble materials except those held chemically 

 or physically (as e. g., by adsorption) in or on 

 the solid particles of the soil. With decreasing 

 rainfall the relative importance of the downward 

 percolation decreases while that of the capillary 

 rise increases. Under moderate aridity (semi- 

 arid conditions) there is still a net downward 

 flow, but it is insufficient to fully leach the soil 

 and there is a tendency for the accumulation of 

 the less soluble materials (usually lime carbon- 

 ate) in the subsoil. Thus are formed the well- 

 known lime-cemented subsoils, the " whitewash," 

 etc., of the southwestern United States. The ex- 

 act process of formation of the so-called " caliche " 

 (the lime caliche — not the sodium salt caliche of 

 South America), " tepetate," etc., is uncertain, 

 but is probably similar. Under extreme aridity 

 there is on many types of soil practically no final 

 downward movement of water. The entire rain- 

 fall is stored in the subsurface layers and returned 



