HISTORY. 
73 
From this time those who worked with tannin busied 
themselves with attempting to arrive at its constitution 
as well as its composition ; Liebig’s formula, C 18 H 16 0 12 , 
did not convey a sufficiently satisfactory idea of what 
relation tannin bore to other allied compounds, espe¬ 
cially to gallic and pyrogallic acids. 
A few investigators stand out prominently. Of 
these Wether ill first carefully investigated the conver¬ 
sion of tannic into gallic acid, by boiling 50 grammes 
of tannic acid with 500 cc. of a solution made by mix¬ 
ing one volume of sulphuric acid, specific gravity 1.840, 
with four volumes of water. He obtained from 100 
parts of tannic acid 87.4 parts of gallic acid. 
About the same time, 1847, Mulder made a valuable 
contribution on the subject. The original being in 
Dutch and in a publication not found in this country, 
a full translation may be found in Buchner’s Reperto- 
rium fur die Pharmacie, 101 , 311, and Erdmann’s and 
Marchand’s Journal , 17, 337. Berzelius, Jahresbericht, 
1850, 224, gave a short abstract of it, and appended 
some critical remarks of his own, which indicated that 
he did not believe this work of Mulder in any way 
superior to the great number of other publications on 
the subject. 
Mulder stated in the introductory remarks that the 
formula of Liebig had been generally accepted, but that 
he found it to be C 28 H 18 0 17 -j- H 2 0, which compactly 
stated in our nomenclature is C 14 H 10 O 9 , or exactly that 
which has been established by more recent investigators 
and is accepted at the present time. This determina¬ 
tion was made on tannic acid which had been dried at 
120°. He gave much credit to Pelouze, and stated that 
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