74 Scientific Intelligence. 



num chloride.* In a nitrogen atmosphere in which the partial 

 pressure of the vapor was 0*75, they obtained at 433° the value 

 10*86 as a mean of two experiments, the formula Fe 2 Cl fi requiring 

 11*25. The vessel used could be examined readily during the 

 operation ; and it was found that even at 440°, the ferric chloride 

 was decomposed into ferrous chloride and chlorine ; the former 

 not being volatile at this temperature was deposited in crystals 

 on the walls of the vessel, and combined again with the chlorine 

 on cooling. The authors thus explain the results obtained by V. 

 Meyer and Griinewald.f To avoid this dissociation, further ex- 

 periments were made in an atmosphere of chlorine, in which the 

 chloride has only a slight pressure. At temperatures between 

 321° and 442° the density remained nearly constant at about the 

 value required by theory. The chloride boiled at 280°-285. — 0. 

 B., cvii, 301 ; Ber. Berl. Chem. Ges., xx, (Ref.) 579, October, 

 1888. G. f. b. 



3. On the Vapor Density of Gallium chloride. — Friedel and 

 Crafts have also determined by the same method the vapor 

 density of the higher chloride of gallium. This density decreases 

 as the temperature rises, falling from 10*6 at 307° to 7*8 at 440°. 

 At 237° -273° approximately constant values are obtained agree- 

 ing closely with the theoretical value 12*2 calculated from the 

 formula Ga 2 Cl 6 . Constant values corresponding to the formula 

 GaCl 3 were not observed. — C. B., cvii, 306; Ber. Berl. Chem. 

 Ges., xxi, (Ref.) 580, October, 1888. G. f. b. 



4. On the Molecular Mass of /Sulphur, Phosphorus, Bromine 

 and Iodine in Solution. — Paterno and Nasini have made use 

 of Raoult's method for the purpose of determining the molecu- 

 lar mass of sulphur, phosphorus, bromine and iodine in solution, 

 the researches of van't Hoff upon the osmotic pressure of liquids 

 leading directly to the assumption that the law of Avogadro 

 holds good in dilute solutions as in gases, the osmotic being sub- 

 stituted for the atmospheric pressure. In the case of sulphur, 

 the solvent used was benzene, the experiments being made with 

 solutions of different strengths. The depression-coefficient ob- 

 tained was constant and led to the molecular formula S 6 , 

 corresponding to that obtained by means of the vapor-density at 

 500°. For bromine, solutions in water and in glacial acetic acid 

 were used ; and numbers were obtained leading to the formula 

 Br 2 . For iodine, the solvents employed were benzene and glacial 

 acetic acid. For very dilute solutions in the former, the results 

 corresponded to the formula I 2 . But for solutions in the latter, 

 values were obtained leading to a formula between I and I 2 , al- 

 though the molecular depression was constant. The phosphorus 

 employed was not quite pure. But its solution in benzene gave a 

 value intermediate between the formulas P 2 and P 4 . — Ber. Berl. 

 Chem. Ges., xxi, 2153, July, 1888. G. f. b. 



5. On the Atomic Mass of Osmium. — The atomic mass of 

 osmium has been determined by Seubert, by reducing ammonium 



* This Journal, III, xxxvi, 465, Dec, 1888. 

 f See this Journal, III, xxxv, 494, June, 1888. 



