26 



SCIENCE. 



[N. S. Vol. XIX. No. 470. 



The precipitate having the composition 

 4MnOj.ZnO contained the highest relative 

 amount of zinc which could be carried down in 

 combination with manganese peroxide. The 

 water of hydration in the precipitates was 

 found to be variable, and its amount at any of 

 the temperatures selected for drying did not 

 correspond to a whole number of molecules. 



The 145th regular meeting of the Wash- 

 ington Chemical Society was held November 

 12 in the assembly room of the Cosmos Club. 

 Dr. H. N. Stokes and Mr. S. S. Voorhees 

 were elected councillors of the American 

 Chemical Society. Dr. Atherton Seidell was 

 elected secretary of the Washington Chemical 

 Society. The first paper on the program, en- 

 titled ' European Notes,' was delivered by Pro- 

 fessor r. W. Clarke. The speaker described 

 Ms recent visit to Manchester, England, in 

 attendance upon the meeting held in honor of 

 the one hundredth anniversary of Dalton's 

 discovery. He also told of his visits to Cam- 

 bridge and the laboratories of Thorpe and 

 Eamsay in London, to a meeting of the Royal 

 Society and the Eoyal Society Social Club. 

 A short account of the meeting of the Con- 

 gress of Applied Chemistry held at Berlin 

 was given, after which he described his sub- 

 sequent visits to Dresden, then to Munich, 

 where he was shown Beyer's laboratory built 

 by Liebig and also made acquainted with the 

 great work in mineralogy which is now being 

 done by Groth. Dr. Clarke also spoke of his 

 visits to Zurich and to Heidelberg. The sec- 

 ond paper, entitled ' The Solubility of Calcium 

 Sulphate in Aqueous Solutions of Sulphuric 

 Acid,' by F. K. Cameron and J. F. Breazeale, 

 was presented by Dr. Cameron. The authors 

 showed that in the presence of any concentra- 

 tion of sulphuric acid the solubility curve for 

 gypsum or calcium sulphate did not show a 

 maximum point, as this substance does in pure 

 water, but increases steadily with increase in 

 temperature. At temperatures from 25° C. 

 to 85° C. the solubility of calcium sulphate 

 increases with increasing concentration of sul- 

 phuric acid until a maximum is reached and 

 then decreases again. The position of the 

 maximum point on the curve, the concentra- 

 tion with respect to calcium sulphate and sul- 



phuric acid respectively being taken as or- 

 dinates, depends upon the temperature. The 

 data obtained seems to negative the assump- 

 tion that both electrolytes yield a common 

 ion. These hypotheses suggest themselves : 



1. That at higher dilutions sulphuric acid 

 yields mainly an HSO^ ion and with in- 

 creasing concentration mainly an SO^ ion. 

 But this assumption is opposed to the results 

 of previous work of others on the conduc- 

 tivity, etc., of solutions of sulphuric acid. 



2. That double or bisulphates are formed. 

 An examination of the solid phase in contact 

 with the solution failed to throw light upon 

 this point. 



3. That other solubility effects than that oc- 

 casioned by the ions masked the action of the 

 latter. 



No satisfactory criteria exist by which these 

 assumptions may be adequately tested. The 

 authors do not regard the facts as necessarily 

 opposed to the dissociation hypothesis. But 

 the hypothesis in its present form is unsatis- 

 factory and inadequate to furnish assistance 

 in the study of such phenomena. 



It was pointed out that in these solutions 

 there was evidence of a condensation of the 

 solvent, water, which might have an important 

 bearing on the apparently abnormal results. 

 Finally, the solubility of calcium sulphate in 

 pure water was discussed in comparison with 

 the results obtained by other investigators. 

 A. Seidell, 

 Secretary. 



THE BIOLOGICAL SOCIETY OF WASHINGTON. 



The 3Y7th meeting was held Saturday 

 evening, November 28. 



H. F. Moore spoke on ' The Artificial Fat- 

 tening of Oysters,' stating that experiments 

 made by the U. S. Fish Commission showed 

 that when placed in artificial ponds, kept at 

 the right degree of temperature and salinity 

 to foster the growth of diatoms, and with the 

 water kept in motion to imitate the movement 

 of the tide, poor oysters rapidly became fat. 



F. H. Hillman described ' The Comparative 

 Effects of the Seed Midge and of Brucho- 

 phagus funehris on the Structure of Clover 

 Flowers and Fruits.' The speaker stated that 



