12 
THE TANNINS. 
ter, (2) a peculiar resin, (3) a green coloring-matter, (4) 
gallic acid, (5) ligneous tissue. “ All of these bodies 
except the ligneous tissue are in strong combination, 
resulting in a body soluble in alcohol, ether, and water. 
It is to this body entire and not to any principle in 
particular that the astringency belongs, since none of 
these compounds alone possess it.” 
In terminating this memoir the author expressed the 
hope that others would repeat his experiments and 
rectify his errors. 
It has been quoted at some length because it is a 
record of experiments that for ingenuity and accurate 
reasoning would do credit to any investigator at the 
present time. The author was wrong in some of his 
deductions, but, when we consider that then all was 
darkness where now we have some light, it may not be 
far wrong to say that he came much nearer the truth 
than does many a one in our day when examining a 
new substance. 
It is due Deyeux to say that he discovered tannin 
when he exhausted nutgalls with ether and described 
the product as a u refined dry and friable extract.’ 
On account of the gallic acid, he overlooked the possi¬ 
bility of there being a still more important substance 
present. All previous investigators had pointed so 
strongly to gallic acid as the principal constituent that, 
notwithstanding he found what he named a peculiar 
resin to be present in great abundance, he was unable 
or unwilling to realize it. Finally, he failed to distin¬ 
guish between gallic and pyrogallic acids, but others 
also had failed to detect that difference. 
We find at this time that the desire to improve the 
