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IX. An Account of some Experiments and Observations on the 
constituent Parts of certain astringent Vegetables; and on their 
Operation in Tanning. By Humphry Davy, Esq. Prof essor of 
Chemistry in the Royal Institution. Communicated by the Right 
Hon . Sir Joseph Banks, Bart. K. B. P. R. S. 
Read February 24, 1803. 
The discovery made by M. Seguin', of a peculiar vegetable 
matter which is essential to the tanning of skin, and which is 
possessed of the property of precipitating gelatine from its solu- 
tions, has added considerably to our knowledge of the constituent 
parts of astringent vegetables. 
Mr. Proust has investigated many of the properties of this 
substance ; but, though his labours, and those of other chemists, 
have led to various interesting observations, yet they are far 
from having exhausted the subject. The affinities of tannin have 
been hitherto very little examined ; and the manner in which 
its action upon animal matters is modified by combination with 
other substances, has been scarcely at all studied. 
At the desire of the Managers of the Royal Institution, I 
began, in September, 1801, a series of experiments on the sub- 
stances employed in the process of tanning, and on the chemical 
agencies concerned in it. These experiments have occupied, 
ever since, a considerable portion of my leisure hours ; and I now 
presume to lay before the Royal Society an account of their ge- 
neral results. My chief design was, to attempt to elucidate the 
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