cxii Journal of the Asiatic Society of Bengal. [N.S., XII, 



Chemical Action and Actinic Rays. — By P. Nbogi. 



On repeating earlier experiments on the emission of chemically active 

 rays from intensely exothermic chemical reactions such as the action of 

 zinc and sulphuric acid, caustic alkalis and sulphuric acid, it was found 

 that the photographic action is not due to chemical action, but due to 

 heat rays. Such photographic action was given by hot water (70°) also. 

 The author is also studying the photographic action of ionised gases and 

 showed photographs of a tin star, iron key, etc., obtained by ionised 

 hydrogen, air, and nitrogen. 



Estimation of Calcium as the Sulphate. — By P. Neogi. 



As the estimation of calcium by the ultimate conversion of calcium 

 oxalate into caustic lime requires very prolonged heating in platinum 

 crucibles by means of a blowpipe, the author converts the oxalate into 

 carbonate in a porcelain crucible by gentle heating and then into sul- 

 phate by the addition of chemically pure dilute sulphuric acid. The 

 resultant sulphate is then moderately ignited and weighed. This method 

 gives satisfactory results and takes much less time. 



Disappearance of volumes by dissolution of substances in 



water. — By Jitendro Nath Rakshit. 



Disappearance of volumes when 100 gms. of some substances are dis- 

 solved in increasing quantities of water have been calculated on a basis 

 of the determination of specific gravities of their aqueous solutions of 

 different strengths. 



Action of Chlorine on a Solution of Silver Nitrate. — By 



R. N. Sen. 



Ar 



of H 2 S.— By J. N. Mukerji. 



The Production, Metallic Derivatives and Constitution of 



Guanidine. — By H. Krall. 



From a quantitative study of the bodies produced by the action of 

 heat on ammonium thiocyanate, it was shown that guanidine thiocyanate 

 is better obtained by heating at 200° for 4 hours than at 185° for 20 hours. 



(vide J.C.S. 1913, 103, 1378.) 



The methods of obtaining potassium, silver and copper derivatives 

 were explained and the isomerism of the silver derivatives was discussed. 

 A tautomeric constitution was suggested which was claimed to be more in 

 accordance with the chemistry of guanidine than the traditional formula. 

 (vide J,C.S. 1915, 107, 1390.) 



Equilibrium between Mercury and Copper Salts in Presence 



of Halogen Ions. — By J. C. Ghosh. 



Reduction of Nitric Oxide by Contact Action of Metals and 



Metallic Oxides, — By B. B. Adhicari. 



Weak 



tion. — By T. C. Chowdhuri. 



Studies in Liquid Crystals. — By T. C. Chowdhuri. 



