430 RECORD OF .SCIENCE FOR 1887 AND 1888. 



Paterno and Kasini with aqueous solutions find tliat citraconic, mes- 

 aconic, and itaconic acids have the same coefiScients of depression, and 

 are therefore strictly isomeric. A like statement holds of malic and 

 fumario acids. (Berichte, xxi, 2156.) 



Louise and Roux, in order to determine the constitution of aluminum 

 compounds, investigated aluminuin ethyl, propyl, and isoamyl by 

 Raoult's method, with ethylene bromide as the solvent. The results 

 agree with the formula? AlgXe, in which X stands for the alcohol radicle. 

 Compare the diverse results obtainedby other chemists with the vapor- 

 density method. (Compt. Rend., cvii, 600.) 



The depression pro Inced in the freezing point of benzene by various 

 phenolic substances was studied by Paterno. Phenol behaves abnor- 

 mally, but ethylphenol, acetylphenol, two nitrophenols, tribromphenol, 

 picric acid, paracresol, methyl salicylate, thymol, nitro thymol, nitro- 

 sothymol, naphthol, and benzylphenol all gave normal results, both in 

 benzene and in acetic acid. (Berichte, xxi, 3178.) 



Density of gases and vapors. — In <liscussing the atomic weight of oxy- 

 gen attention was called to Lord Rayleigh's observation that the volnme 

 of a glass globe when full differs from the volume of the same globe 

 when empty. This observation affects all of Regnault's determinations 

 of the weight of gases, and the results of the latter have been cor- 

 rected by Crafts, who had access to Regnault's original apparatus, ex- 

 cepting the glass globe actually used, which had been destroyed. An- 

 other globe of the same lot, however, was available, and presumably 

 identical for all practical purposes with it. The following are the spe- 

 cific gravities as given by Regnault and as corrected by Crafts, air being 

 taken as unity. 



Regnault. Crafts. 



N 97137 .97138 



H 06927 .06949 



1.10564 1.10562 



CO, 1.52910 1.5i^897 



The actual correction was 3 milligrammes added to the weight of 

 each gas as given by Regnault at 760 millimeters pressure. (Compt. 

 Rend., cvi, 1662.) 



J. Mensching ami Victor Meyer find that at high temperatures the 

 vapors of jihosphorus and arsenic are not in agreement with the sup- 

 posed molecules P4 and AS4, but that at a white heat they approximate 

 to P3 and As2. For antimony the molecule Sb, does not exist, the 

 probable molecule being either Sbj or Sb,. (Berichte, xx, 1833.) 



Blitz, redetermining the vapor density of sulphur, under various con- 

 ditions, obtains values ranging from 7.937 down to 4.734. He concludes, 

 hence, that the commonly accepted view that free sulphur in vapor is 

 Sg is not correct, and that the true formula is S2. (Berichte, xxi, 2013.) 



With reference to the chlorides of iron, chromium, indium, gallium, 

 and aluminum, various determinations have been made, with varying 

 results, First, as to aluminum, whose chloride has hitherto been writ- 



