which possesses the characteristic Properties of Tannin. 121 
was examined by a solution of isinglass, but not any apparent 
effect was produced. 
2. 
On an equal quantity of the walnut peels, in the same soft 
black state, a small portion of nitric acid was poured, and 
after being digested for about five hours, the whole was 
evaporated to dryness. The residuum was of a brownish 
orange colour, and yielded a similar coloured solution to 
water when digested with it. This was filtrated, and upon 
the addition of solution of isinglass, became turbid, and depo- 
sited a tough precipitate, which was not dissolved by boiling 
water. 
3 - 
Another portion of the walnut peels was moderately roasted, 
and was then digested in water ; the brown solution was fil- 
trated, and formed a slight precipitate with gelatine. 
4 - 
On the residuum of the last experiment, a small quantity 
of nitric acid was poured, some water was then added, the 
whole was digested during about five hours, and until it 
became perfectly dry. 
Water formed with this a brown liquor, which yielded a 
very abundant precipitate by the addition of dissolved isinglass. 
Upon these experiments we may remark, that the solution 
in the first instance contained carbon in a state approaching 
to coal, for when treated with nitric acid in the second expe- 
riment, a portion (although small) was produced of the same 
tanning substance which is formed from the different kinds of 
coal by nitric acid. 
MDCCCVI. 
R 
