M. Cahours on Organo-metallic Compounds. 197 



It combines with bromine, with sulphuric acid, with the ele- 

 ments of water, and with hydrogen, to form derivatives parallel 

 to those of olefiant gas. 



Acetylsulphuric acid is formed like ethylsulphuric acid, when the 

 gas is agitated for a long time with concentrated sulphuric acid. 

 The mixture, saturated with carbonate of baryta, filtered and 

 evaporated, yields crystallized acetyls ulphate of baryta. If the 

 mixture is distilled instead of being saturated, a peculiar liquid 

 is obtained somewhat more volatile than water, very alterable 

 and endowed with a peculiar odour, and soluble in 10 to 15 

 parts of water. It is acetylic alcohol, C 4 H 4 O 2 . 



Acetylene may be changed into olefiant gas by causing the 

 nascent hydrogen produced by the action of zinc on ammonia to 

 act upon the compound of acetylene and copper. The olefiant 

 gas thus formed is mixed with hydrogen and a little acetylene, 



C 4 H 2 + H 2 =C 4 H 4 . 



Berthelot* has effected the direct synthesis of iodide of ethyle. 

 A thin sealed tube containing about 20 cubic centims. of a satu- 

 rated solution of hydriodic acid, is introduced into a long-necked 

 globe of about a litre capacity ; the globe is filled with dry ole- 

 fiant gas and hermetically sealed. The tube in the inside is then 

 broken, and the flask heated for fifty hours to a temperature 

 of 100°. 



The flask is then opened, the contents treated with a solution 

 of potash; the product, washed, dried, and rectified, yields 

 about 4 grms. of pure iodide of ethyle. 



M. Cahours has publishedf an extended memoir on organo- 

 metallic radicals. We can only find space for a few of the more 

 interesting results. 



When iodide of ethyle acts on alloys of tin and sodium con- 

 taining 2 to 12 per cent, of the latter, iodide of stan ethyle is 

 formed, mixed with a large quantity of an irritating oil smelling 

 like mustard. It boils between 234° and 236° C, and has the 

 formula (C 4 H 5 ) 3 Sn 2 I. It is the iodide of sesquistanethyle. 



With an alloy of 4 parts of tin and 1 part of sodium two pro- 

 ducts are obtained. One an oily, limpid, yellowish liquid, which 

 unites directly with oxygen or iodine to form oxide or iodide of 

 sesquistanethyle ; it is the sesquiethylide of tin, Sn 2 (C 4 H 5 ) 3 . 

 The other is a viscous liquid, stanethyle, Sn C 4 H 5 . 



When this radical is treated with water a thick oil separates, 

 which, when heated, decomposes into metallic tin and a colour - 



* Comptes Rendus, March 1860. 



f Annates de Chimie et de Physique, vol. lviii. p. 5. Repertoire de 

 Chimie, vol. ii. p. 167. 



