374 Proceedings of Philosophical Societies. [May, 



KOYAL ACADEMY OF SCIENCES AT PARIS. 



An Anali/sis of the Labours of the Rot/al Academy of Sciences 

 of Paris duriyigthe Year 1818. 



(Continued from p. 305.) 



Physical Sciences. — By M, Le Chevalier Cuvier, Perpetual 



Secretary. 



CHEMISTRY. 



Chemistry has been enriched this year with two new substances 

 which are doubly interesting ; because one is a substance not 

 only metaUic, but also alkaline ; that is to say, its oxide is a new 

 fixed alkali ; and the other is metaUic, acidifiable, and more ana- 

 logous to sulphur than to any other substance. 



We owe the first to M. Arfvedson, a young Swedish chemist, 

 a pupil of Prof. Berzelius. M. Arfvedson discovered it in a 

 stone called petalite, in which he did not find more than from 

 three to five per cent, of it ; but he afterwards found as much as 

 eight per cent, of it in another stone called triphane. 



This substance affords very fusible salts, with the greatest part 

 of the acids ; its carbonate, when melted, attacks platinum nearly 

 as powerfully as the nitrates of the other alkahes, and is difficultly 

 soluble ; its muriate is very deliquescent ; its sulphate crystallizes 

 without any water of crystallization. The capacity of this alkali 

 for saturating acids is much greater than that of any other alkali, 

 and it also enters into the salts which it forms with the acids in a 

 much greater proportion. 



The author of this discovery has g-iven the name of lithion to 

 this new substance, in order that we may recollect that this alkali 

 was discovered in a mineral ; whereas the other two fixed alka- 

 lies were originally extracted from vegetables. 



The second new substance was discovered by Prof, Berzelius 

 himself in a manufactory of oil of vitriol, at Fahlun, in Sweden. 

 There is deposited on the floor of the chamber where the sulphur 

 (distilled from pyrites) is burned, a reddish mass, which, for the 

 most part, consists of sulphur ; but on being set on fire, it exhales 

 a very strong odour of horseradish. Now this smell being one 

 of the characters belonging to a metal discovered a few years 

 ago by M. Klaproth, and called tellurium, it was suspected that 

 this smell was owing to a mixture of this metal with the sulphur. 

 Nevertheless Messrs. Berzelius and Gahn, who first examined 

 this red substance, were not able to extract any tellurium from 

 it. The first mentioned gentleman carried some to Stockholm, 

 in order to examine it more closely, and found in it a very vola- 

 tile substance, very easily reducible, and which was not precipi- 

 table by alkalies. Its colour is grey, very shining, it is hard, 

 friable, and its grain resembles that of sulphur. Its specific 



