150 Proceedings of Philosophical Societies. [Fes, 
afterwards to pour some cold water on the grain, and to stir it about 
in order to wash away completely the water which holds the must in 
solution. Grain thus treated will be found quite free from all 
musty taste. In a year like the present, when so much of the corn 
has been injured by wet, this information must be of great import- 
ance to the country. 
On Thursday, Dec. 12, a paper by Mr. Brande, on an astringent 
substance from China, was read. It was given to Mr. Brande for 
examination by Sir Joseph Banks, It consisted of vesicular 
bodies like nutgalls adhering to the smaller branches of a tree. 
Insects could be perceived in it. ‘There is a description of it by 
Duhalde, who says, that it varies from the size of a nutgall to that 
of achesnut. Mr. Brande found its constituents as follows :— 
Tannin and gallic acid ......+-+-++eees 75 
BRGSU v.59 .s.0:t ie 8 0:2 PEE UTE Ferre 2 
Woody fibre ......+--+--eeee ee .. 23 
. 100 
The tannin was of a brownish-yellow colour, and had an astrin- 
gent taste. It was completely soluble in water and in alcohol of 
0-820. It threw down peroxide of iron of adeep black from acids, 
The author tried to separate the gallie acid from the tannin by 
Davy’s process; namely, digesting the solution with barytes, filter~ 
ing and then throwing down the barytes by sulphuric acid. But 
this process did not succeed. He succeeded better when he digested 
lime in the solution, filtered, and then threw down the lime by 
Oxalic acid. But even this process did not give pure gallie acid. 
Mr. Brande found his tannin very soluble in aleohol of the specifie 
gravity 0°820. He, therefore, draws as a conclusion, that the pre- 
vious statement of chemists, that tannin is insoluble in absolute 
alcohol, is inaccurate. Had he consulted my System, of Chemistry 
(vol. ii. p. 392), he would have seen that | had long agoascertained 
the solubility of tannin in alcohol of the specific gravity 0°818, 
which is an alcohol containing only 2; of its weight of water. But 
this is no reason for refusing to admit the accuracy of Richter’s ex- 
periment, that tannin is insoluble in alcohol of the specific gravity 
0-796. 
Mr. Brande found, as had been done long ago by Scheele, that 
when nutgalls are distilled a quantity of the gallic acid comes over 
undecomposed. — 
On Thursday, Dec. 19, a paper by M. Dupin was read, on the 
Improvements lately introduced into Ship-building by Mr. Seppings. 
‘The author, in order to obtain materials for his projected work on 
ship-building, had been induced’ to visit Great Britain ; and he ex- 
pressed himself in the highest terms of the reception he met with, 
from those gentlemen to whom he had occasion to apply. He 
stated a number Of historical facts to show that the principle upon 
which. Mx. Seppings’s plan is foanded had. been previously known 
