44 
Selected Articles, 
into it, and the remaining space to be filled with sulphuric 
ether, and the cork closely fitted in, the ether slowly filtrates 
through the powder and falls into the receiver. This fluid is 
to be several times passed through the galls ; it becomes of a 
greenish colour ; on standing, it deposits a brownish syrupy 
crust, which collected in a funnel by decantation, washed 
with sulphuric ether, and again decanted, holds the pure tan- 
nin in solution. It suffices to evaporate this etherial liquid in 
vacuo, or in a water bath, to dryness ; in the first place a 
voluminous, whitish, yellow foliated product is obtained, which 
is very light and readily pulverizable ; in the latter, the pro- 
duct is in the form of a greenish mass, which is soft when 
hot, and dry and brittle when cold, and readily reducible into 
a white powder. 
Having thus at my command very pure and dry tannin, I 
commenced by dissolving a certain quantity in a vessel filled 
with cold water, protecting it from the action of the air. The 
solution, at first, took place slowly, the fluid then became 
more viscous, forming a brownish layer, which covered the 
bottom of the vessel, and was readily mixed with the re- 
mainder of the fluid by stirring ; the solution was then com- 
plete, and after filtration it had a light greenish brown co- 
lour. 
To ascertain how much pure tannin it contained, I took 
two equal portions, namely, fifteen grains, and poured into 
one a solution of tartar emetic, and into the other, neutral 
acetate of lead ; the precipitates were washed and dried. I 
obtained — 
1. Tannate of antimony Sb 2 3 f 3 = 0.69 gr. 0.68 gr.; 0.685 gr. 
2. Tannate of lead prf = 0.82 gr. 0.84 gr.; 0.84 gr. 
which gave of pure tannin with the salt of antimony, 0.5576 
grains, and with the salt of lead, 0.5398 grains, for one atom 
of tannate of antimon. contains, 
Protox. antimon. ( 1012.90, or 19.18. 
Tannin [ 8064.59, or 80.12. 
One atom of tartrate of lead contains — 
Protox. lead ( 1394.498, or 34.16. 
Tannin \ 2688.198, or 65.84. 
