466 
MR. G. B, BUCKTON AND DR. A. W. HOFMANN’S RESEARCHES ON THE 
4 equivs. of Carbon . . 
( 
24 
Theory. 
A 
7*38 
Experiment. 
4 equivs. of Hydrogen . 
4 
1*23 
2 equivs. of Barium . . 
. 137 
42*15 
42*36 
4 equivs. of Sulphur . . 
64 
19*69 
19*68 
12 equivs. of Oxygen . . 
96 
29*55 
325 
100*00 
For the determination of the water of crystallization, 0*5790 grm., dried at 100°, were 
heated to 220° C., when they lost 0*0347 gi’m. Two equivalents of water require 5*24 ; 
found, 5*99. It is probable that there is a partial decomposition of the salt at this 
high temperature. 
As has been already stated, the disulphethylates may also be prepared from pro- 
pionitrile. For this purpose three parts of the propionitrile are distilled with two 
parts of fuming sulphuric acid. As the action is very energetic, the mixing should 
be effected by degrees in a moderate-sized retort. A barium-salt was prepared the 
properties of which agreed in every respect with those of the compound prepared 
from propionamide. 
Disulphetholic Acid 
is obtained by decomposing the lead-salt by hydrosulphuric acid. By concentration 
it forms a thick syrup, which ultimately solidifies into a crystalline mass. By heat 
it decomposes with deposition of charcoal and production of white fumes. 
Disulphetholate of Silver 
may be obtained by a process similar to that employed in the case of the disul- 
phometholate. It is crystalline. When dry, it bears a considerable heat without 
change. The solution blackens on ebullition. 
Disulphetholate of Lead 
is very soluble in water. When evaporated over sulphuric acid, the salt yields fine 
prisms or minute quadrangular laminae. When hastily evaporated it produces a 
tough gummy mass. 
Sulphopropionic Acid. 
As might have been anticipated from the results obtained in the methyl-series, 
disulphetholic acid is by no means the sole product of the action of sulphuric acid 
upon propionamide and propionitrile. The formation of this acid is preceded by that 
of another acid richer in carbon and poorer in sulphur, in one word, by that of sulpho- 
propionic acid. The uncrystallizable ammonium-salt, already mentioned, is in fact 
the sulphopropionate of ammonium. Absolute alcohol throws it down from its 
solution as a thick treacly mass, with an appearance very unprepossessing to the 
