332 Analysis of the Labours of the Royal Academy 



Sir H. Davy has given the name of chlorine, another explana^ 

 tion must be sought for. Messrs. Robiquet and Colin have de-^ 

 voted themselves to tins object. They have found that by passing 

 slowly into a balloon a volume of olefiant gas and two volumes 

 of chlorine, they become entirely converted without any residue 

 into an oily liquid, which decomposed by heat gives hydrogen 

 not satiirated with carbon, a deposit of carbon, and a good deal 

 of muriatic gas — that is to say, according to the new theorv, hy- 

 drochloric gas. The chlorine therefore enters in susbtance into 

 the oily liquid. But is it there as chlorine, and united directly 

 to the subcarburetted hydrogen ? or, rather, is it there united to 

 the hydrogen, and as hydrochloric acid, or in other words mu- 

 riatic? It is to the first of these conclusions that Messrs. Robi- 

 quet and Colin have been led, by indications deduced from the 

 specific weight of the components and of the compound : while, 

 muriatic ether, which has many resemblances to this oily liquid, 

 appears to them on tlie contrary to be formed by the tmion of 

 hydrochloric gas with carburetted hydrogen. 



M. Chevreul continues still to labour with the same zeal iii 

 his Chemical History of Greasy Bodies. In a memoir presented 

 to the Academy this year, this laborious chemist has begun to 

 examine the causes to which the consistency, the odour and the 

 particular colour of some oils and fats are owing. The varieties 

 of consistency are regulated by two general principles of greasy 

 bodies ; but the other differences depend on particular and fo- 

 reign principles. M. Chevreul proposes a system of nomencla- 

 ture analogous to tlie rest of chemical nomenelatiue, as well 

 for the principles which he has dincovered as for their saline 

 combinations. The two principles of grease ought accordingly 

 to be named steatine and elame, from the Greek words which 

 signify fat and oil. Its principal acid, that which is most con- 

 sistent, will be margaric acid ; the other, elaic acid. Spermaceti 

 will take the nauje of ccline, '6:c. &c. I'hese names are no 

 doubt burdensome to ihe memory, but that is an incouvenienc& 

 inseparable fiom the progress of science. 



Mineralogy avd Geology. 



Greenland has for several years furnished a stone in small 

 crystals of a sea-green colour, which has been named sodalite 

 from its containing nearly a fourth of its weight of soda united 

 with silex and aUunme. 



The Count Dunin-Bovkowsky, a Gallician gentleman and 

 mineralogist, as zealous as well informed, has discovered a co- 

 lourless variety of the same stone in large prisms, in that part 

 of Vesuvius called Fosso-grande, so celebrated for the number 

 and variety of the mhierals with which it has supplied collectors. 



The 



