on the constituent Parts of astringent Vegetables . 243 
other case, precipitated gelatine slightly, but the salts of alumine 
copiously ; and it gave a tinge of red to litmus paper. 
When solution of lime, of strontia, or of barytes, was poured 
in excess intq a portion of the infusion, a copious olive-coloured 
precipitate was formed, and the solution became almost clear, 
and of a reddish tint. In this case, the tannin, the gallic acid, and 
the extractive matter, seemed to be almost wholly carried down 
in the precipitates ; as the residual fluids, when saturated by an 
acid, gave no precipitate to gelatine, and only a very slight tint 
of purple to oxygenated sulphate of iron. 
When the solutions of the alkaline earths were used only in 
small quantities, the infusion being in excess, a smaller quantity 
of precipitate was formed, and the residual liquor was of an 
olive-green colour ; the tint being darkest in the experiment 
with the barytes, and lightest in that with the lime. This fluid, 
when examined, was found to hold in solution a compound of 
gallic acid and alkaline -earth. It became turbid when acted on 
by a little sulphuric acid ; and, after being filtrated, gave a black 
colour with the solutions of iron, but was not acted upon by 
gelatine. 
When a large proportion of lime, was heated for some time 
with the infusion, it combined with all its constituent principles, 
and gave, by washing, a fluid which had the taste of lime-water, 
and which held in solution only a very small quantity of ve- 
getable matter. Its colour was pale yellow ; and, when saturated 
with muriatic acid, it did not precipitate gelatine, and gave only 
a slight purple tinge to the solutions of the salts of iron. The 
lime in combination with the solid matter of the infusion, was of 
a fawn colour. It became green at its surface, where it was ex- 
posed to the air; and, when washed with large quantities of water, 
I i 2 
