NOTE UPON TANNIN. 
235 
It is certain, that in hands skilled in this work, the execution 
of the process which occupies us is easy, but it isnot less 
true, that in other hands it is always variable, and the quantity 
of tannin obtained is different according to the nature of the 
ether employed. 
The method of M. Le Connet furnishes more tannin with 
less expense; but the execution is little convenient and the 
product less pure. 
I have searched, but uselessly, for a method, by the aid of 
which it was possible to extract from nut galls, with facility 
and certainty in the results, 46 or 50 per cent, of tannin, suffi- 
ciently pure for the uses of medicine. 
I have submitted nut galls to many modes of treatment, 
yet I shall content myself with stating but one of them. 
Extraction of Tannin by hydro-alcoholic sulphuric ether. 
J& Rectified sulphuric ether, 12 oz. 
Alcohol at 30° Cartier, 3 " 
Distilled water, 1 " 
Total, 16 oz. 
Nut galls in fine powder, 8 " 
Suspend the powder in half of the ethereal liquid, place the 
mixture in a funnel with a stopcock, pour upon it the remain- 
der of the solvent, and after six hours contact open the cock 
and collect the fluid which runs off, taking care at the same 
time to add 4 or 5 ounces of water, in order to displace the 
ether retained by the powder. You obtain a yellow solution, 
about 12 or 13 ounces in weight, and which will furnish by 
proper evaporation near 4 ounces of tannin. Thus obtained, 
the tannin has a pale yellow color, due to a small'quantity of 
coloring matter ; it can become of use in the arts. 
Journ. de Chim. Med. 
