TARTARIC AND PARATARTARIC AGTDS, &C. 329 
in water and diluted alcohol, and are changed by ebullition in 
water, into alcohol and tartaric acid. 
Treated with an alkali between 160° and 170°, they disen- 
gage alcohol, acetic ether, and an excessively bitter oily sub- 
stance. 
The tartrovinate of silver is anhydrous; all the others studied 
by the writer, contain water of crystallization, which can 
be removed by evaporation. 
The dry tartrovinates can be regarded as formed of 2 atoms 
of tartrovinic acid, 1 atom of ether, and 1 atom of the base. 
Paratartrovinic Acid. — This is obtained in the same way 
as the tartrovinic acid, from which it only differs in composi- 
tion by an extra atom of water. Its chemical properties are 
very different from those of tartrovinic acid. The same is the 
case with the corresponding salts which are formed by the 
acids, although the paratartrovinates have, when dry, the same 
composition as the tartrovinates. The spirit of wood, (bihy- 
drate of methylene,) submitted to a similar action of tartaric 
and paratartaric acids, produces tartromethylic and paratar- 
tromethylic acids, which in composition and the salts which 
they form, perfectly correspond to the tartrovinic and para- 
tartrovinic acids and their salts. 
Journal de Pharmacie. 
VOL. II. — no. iv. 
42 
