September 9, 1921] 



SCIENCE 



229 



solutions are two-phase systems in which the dis- 

 persed phase has a negative charge. Probably 

 hydroxyl ions are absorbed on the particles and 

 attract sodium ions to form double layers which 

 cause higher concentrations of alkali at the inter- 

 faces than elsewhere in the solution. This hypoth- 

 esis explains discrepancies between the results from 

 various methods. 



Compression evaporation: A new metlwd of con- 

 centrating liquids developed in Europe recently: 

 GusTAV Carlsson. 



Action of lime on greensand : E. Noekis Shreve. 

 The Eastern Potash Corporation has under con- 

 struction at New Brunswick, N. J., a large plant 

 for obtaining caustic potash and other potash com- 

 pounds from greensand. The main reaction in the 

 process is the action of lime in decomposing green- 

 sand whereby caustic potash is liberated and a valu- 

 able residue obtained, which possesses considerable 

 cementitious properties. In the reaction the lime 

 attacks the greensand, or rather the glaueonite 

 contained therein, when heated with the greensand 

 in the presence of water and at elevated tempera- 

 tures and under sufBcient pressure to keep the 

 water in the liquid phase. 



A modification of the acetate method for esti- 

 mating iron and albumen in phosphates: F. P. 

 Veitch and H. P. Holman. As a result of co- 

 operative work with the fertilizer division of the 

 American Chemical Society and also independent 

 investigations, certain modifications have been 

 made in the acetate method for estimating iron 

 and aluminum in the presence of lime and phos- 

 phoric acid. This method, in substantially its 

 present form, was submitted by the authors to the 

 committee on research and analytical methods of 

 the fertilizer division and was published as a part 

 of that committee 's report on phosphate rock in 

 Journal of Industrial and Engineering Chemistry, 

 7, pp. 446-448. The present article made further 

 modifications as a result of subsequent work, dis- 

 cussed the reasons for the conditions described as 

 necessary for accurate results by this method, and 

 gave results obtained on solutions of known com- 

 positions. 



The loader resistance of treated canvas during 

 continuous exposure to weather: F. P. Veitch 

 and T. D. Jarrell. This paper gives a detailed 

 report on the water resistance of gray 12 oz. 

 XI. S. standard army duck, which had been treated 

 with eighteen formulas developed in the Bureau 

 of Chemistry. The degree of water resistance 

 was determined in the laboratory by modified fun- 



nel and modified spray methods and also in actual 

 service by exposure to weather for 14 months. 

 General conclusions are drawn as to the eifective- 

 uess of the various treatments. The treatments 

 which have proved most serviceable by exposure 

 test have also given high results by the funnel 

 test. However, not all treatments showing a high 

 rating by the funnel test have proven highly serv- 

 iceable in those cases where water lay for some 

 time on the canvas. 



The detection and estimation of coal tar oils in 

 turpentine: V. E. Grotlisch and W. C. Smith. 

 The method outlined includes the following steps: 



(1) passing dry hydrogen chloride gas into the 

 liquid, thus converting the pinene into crystal- 

 line pinene hydrochloride, also raising the boiling 

 points of the unprecipitated reaction products; 



(2) distillation of the filtrate under reduced pres- 

 sure to separate the coal tar oils with a minimum 

 of terpene bodies; (.3) sulphonation of the distil- 

 late with fuming sulphuric acid, thereby destroy- 

 ing terpenes and converting coal tar hydrocarbons 

 into sulphonie acids; (4) dilution and steam dis- 

 tillation of the sulphonation mixture to remove un- 

 decomposed terpenes or mineral oils; (5) direct 

 distillation of the sulphonation mixture to break 

 up the sulphonie acids, with recovery of the 

 coal tar hydrocarbons. 



Charles L. Parsons, 



Secretary 



THE ROYAL SOCIETY OF CANADA 



The following papers were presented before 

 the Mathematical, Physical and Chemical Sec- 

 tion of the Eoyal Society of Canada at the 

 meeting held in Ottawa on May 18, 19 and 20 : 



Presidential Address. — " Division in rela- 

 tion to the algebraic numbers," by Professor 

 J. C. Fields. " Ionization potential and the 

 size of the atom," by Professor A. S. Eve. 

 " Detection of variation in electric earth cur- 

 rents by coil and galvanometer," by Professor 

 A. S. Eve and Mr. E. S. Biehler. " The effec- 

 tive range of beta-rays," by Miss V. Douglas 

 and Dr. J. A. Gray. " The velocity of sound 

 in air and soil ; Properties of x-rays excited by 

 beta-rays; The absorption of gamma-rays; 

 A note on the examination of materials by 

 x-rays," by Dr. J. A. Gray. " The trans- 

 mission of heat through the thin boundary 

 films of air or of water at the surface of glass," 

 by Dr. A. Norman Shaw and Mr. L. S. Smith. 



