which possesses the characteristic Properties of Tannin. 113 
lected, was digested in alcohol, which dissolved the greater 
part. 
The solution in alcohol was filtrated, but (apparently by the 
effect of air) a considerable deposit was formed on the filter, 
which was again dissolved by alcohol. Water rendered the 
solution turbid, and a black light flaky substance, which 
weighed 41 grains, remained upon the filter. The filtrated 
liquor was then evaporated, and left a grayish-black substance, 
which weighed 30 grains. This last substance was highly 
inflammable, and when burned, emitted a very peculiar odour, 
resembling partly that of fat and partly that of asphaltum. It 
easily melted, and also immediately dissolved in cold alcohol, 
from which, like the resinous substances, it was precipitated 
by water. 
The black light flaky residuum, which weighed 41 grains, 
was found to consist partly of the substance above mentioned 
and partly of coal, but the proportion of this last was not 
ascertained. 
“ Coagulated albumen and prepared muscular fibre were also 
separately exposed to the action of sulphuric acid in the 
manner above described, but did not afford any substance by 
which gelatine could be precipitated, coal being the only 
product which remained. 
Almost every one of the bodies which have been employed 
in these experiments, seem to be in some measure different 
in respect to the progressive effects produced upon them 
by sulphuric acid ; and all other circumstances being similar^ 
there appears to be a certain period of the process when the 
production of the tanning substance has arrived at its maxi- 
mum, after which, a gradual diminution of it takes place, and 
MDCCCVI.. O 
