161 



very soluble in water. It was purified by repeated and partial pre- 

 cipitation with alcohol. This substance, when dried at a tempera- 

 ture of 165 C., furnished upon analysis numbers agreeing with the 

 expression C 6 (H 6 Ba 2 ) S 4 O 12 , 



which is that of disulphopropiolate of barium. 



PHENYL-SERIES. 



Action of Sulphuric Acid upon Benzonitrile. 



From the results obtained in the study of the methyl-, ethyl-, and 

 propyl -series, we may fairly infer that all the homologues of other 

 groups will exhibit a similar deportment. 



It appeared, however, desirable to extend our researches to a class 

 of bodies which are analogous (not homologous) to the preceding 



Sulphuric acid appears to act with much less energy upon benzo- 

 nitrile or cyanide of phenyl than upon the foregoing nitriles. No evo- 

 lution of gas is observed until the mixture of the two substances is 

 strongly heated, and then so much sulphurous acid is formed from 

 charring of the cyanide that its presence is almost entirely masked. 



The digestion was continued for two hours, after which the dark 

 residue was treated in the usual manner for the soluble barium-salts. 

 That first obtained consisted of sulphobenzoate of barium. For 

 identification, both the neutral and acid compounds were prepared, 

 the respective formulae of which, 



C l4 (II 4 Ba 2 )S 2 10 , 

 and 



C 14 (H 5 Ba)S 2 1() , 



were corroborated by analysis. 



An examination of the mother-liquor proved, as we had antici- 

 pated, the presence of a more soluble salt. By rapid evaporation it 

 appears as an amorphous mass, but a drop allowed to dry sponta- 

 neously on the stage plate of the microscope exhibits it in the form 

 of minute shuttle-shaped crystals. 



The formula of this body, deduced from a sulphur- and barium- 

 determination, is c< m TCO ^ <s n 

 C, 2 (H 4 Ba 2 ) S 4 O 12 , 



which characterizes it as disulphobenzolate of barium. 



