RECORDS OF MEETINGS 379 



Summary op Papers. 



• Dr. Pacini gave a study of the distribution of ferric chloride under 

 the conditions which obtain in the use of Kothe's method for the de- 

 termination of aluminum, nickel and other metals in steel, the mixed 

 chlorides in hydrochloric acid solution being shaken out with ether which 

 removes the greater portion of the ferric chloride. ]STo decisive knowl- 

 edge was gained regarding the state of molecular aggregation of the 

 ferric chloride in the ether solution insomuch as data concerning the 

 degree of disassociation of ferric chloride in aqueous solution are not at 

 present available. 



Graphical treatment of the constants obtained yields a curve of two 

 distinct sections : in low concentrations up to about 0.38 mols per liter 

 in the ether layer, a straight line ; above this point a parabola satisfying 

 the equation (C E — .38) 2 = KC W , where K= + 1-8. 



The application of the results to analytical separation lies in the 

 fact that the percentage of iron extracted from a hydrochloric acid 

 solution by shaking out with ether is greater relatively as the concen- 

 tration is lower, that is to say, the more dilute the original hydrochloric 

 acid solution of iron, the nearer complete is the extraction of ferric 

 chloride therefrom by ether. 



Professor Poor gave a brief outline of the theories of the tides as 

 developed by La Place, Darwin and others, and contrasted these older 

 theories with recent investigations and theories of Dr. Harris, of the 

 United States Coast and Geodetic Survey. Until the researches of Dr. 

 Harris appeared, the tides were considered as a world phenomenon, 

 and primarily due to a large wave which originates in the Pacific Ocean 

 and travels around the world at varying speeds, due to the depth of the 

 oceans. This wave was supposed to take some fifty hours to travel from 

 the Pacific around Cape Horn to the shores of Few York. Dr. Harris 

 considers the tides as purely local phenomena; the tide of each ocean 

 basin is primarily due to a standing wave or oscillation originating in 

 that basin and practically independent of the oscillations or tides in other 

 basins. The tides at New York and the Atlantic Coast, under this theory, 

 originate in the North Atlantic basin and are wholly independent of the 

 tides in the Pacific and Indian Oceans. 



The Section then adjourned. 



F. M. Pedersen, 



Secretary. 



