545 



our exertions, like those of our predecessors, have not yet been 

 crowned with success. The researches on which we have been 

 engaged, have, however, furnished some results which appear to us 

 worthy of the interest of chemists, the reactions being at the same 

 time remarkable for their neatness and susceptibility of general 

 application. 



Acetonitrile may be considered as the type of its class, both from 

 the importance of the group to which it belongs, and the facility of 

 its preparation. It is, in fact, the nitrile with which we have been 

 specially engaged. This body when mixed with its own volume of 

 fuming sulphuric acid, evolves a considerable amount of heat, 

 accompanied by a very energetic reaction. 



If care be taken to add the acid in small quantities, and to cool 

 the mixture after each addition, scarcely any change of colour is to 

 be observed. By the addition of water, and subsequent saturation 

 with carbonate of barium, a crystalline salt is produced in consider- 

 able quantity, which possesses all the characters and composition of 

 the sulphacetate of barium, 



C 4 (H 2 Ba 2 ) 4 2 S0 3 , 



discovered some time ago by M. Melsens in the mutual reaction of 

 anhydrous sulphuric acid upon glacial acetic acid. 



If, on the contrary, the mixture of acetonitrile and fuming sulphuric 

 acid be made rapidly, and the liquid be rather strongly heated, an 

 abundant evolution of carbonic acid indicates a more profound 

 reaction. The residuary mass, which is tough and of a resinous 

 consistency, when treated with water, and boiled with excess of 

 carbonate of barium, yields a magnificent crystallization of a salt 

 represented by the formula 



C 2 (H 3 Ba Q )4SO 3 + 4aq. 



It is a substance of remarkable stability. It does not lose weight 

 at a temperature of 100 C., but four equivalents of water of crystal- 

 lization are disengaged at 170 C. It is not further affected by a 

 temperature of 220 C. A strong heat resolves it into water, sul- 

 phide of barium, sulphurous acid, free sulphur, and carbonic oxide. 

 It may be boiled for hours with fuming nitric acid without the 

 slightest decomposition. 



We have also made analyses of the ammonia and silver salts. 

 The former crystallizes with great facility in colourless oblique 



