THE DISCOVERY OF THE TANNINS. 
11 
galls. It is then stated that, “ in the number of prop¬ 
erties which appertain to nutgalls, there is one, very 
remarkable, which has always fixed the attention of 
chemists,—namely, the precipitate of the solution with 
the solution of iron salts. This has been attributed to 
an astringent body ,—‘principe astringent 
“ Among those who have occupied themselves with 
this subject may be mentioned Cartheuser, Bouelle, 
Macquer, Monnet, and Giannoti; but it is principally 
the academicians of Dijon, likewise Scheele, Berthellot, 
Fourcroy, and others, to whom we are indebted for the 
positive knowledge of this singular substance. They 
have demonstrated the existence of a peculiar acid which 
they have named gallic acid. This has made desirable 
a knowledge of the other constituents, and it is this 
which is made the subject of the following memoir.” 
The record of the experiments was made under eight 
sections, as follows: 
1. “ The action of water on nutgalls. 
2. “ The action of alkalies on the infusion and de¬ 
coction of nutgalls. 
3. “ The action of alcohol and ether on nutgalls. 
4. “ Distillation of nutgalls with water. 
5. “ Dry distillation of nutgalls. 
6. “ Examination of the gallic acid which sublimes 
during the distillation of nutgalls. 
7. u Examination ot the precipitate which forms 
when nutgalls, their solution, and gallic acid are added 
to ferrous sulphate. 
8. “ Recapitulation.” 
This last section may be briefly stated as follows: 
Nutgalls are composed of (1) a true extractive mat- 
