156 COMBINATIONS OF THE ALKALOIDS WITH TARTARIC ACID. 
cent.; from thenee to 248°-284°, so much more that the entire loss 
amounts to 2*43 per cent- 
Tartrate of Strychnine, C 44 H 24 N 2 O 4 , HO, C 4 H* 5 +4HO.— 
Strychnine behaves like quinine towards tartrate of potash; when 
the solution of the latter has been saturated with the alkaloid, 
shining needles more than an inch in length separate, which dis- 
solve in water and in weak alcohol. The same salt is obtained 
from a neutral solution of strychnine in tartaric acid ; it effloresces 
in the air without falling to a powder, becomes anhydrous at 266° 
and may be heated to 302° without further loss. 
The salt prepared from bitartrate of potash gave in one experi- 
ment 7-76 per cent, of water, and left on ignition an exceedingly 
small residue of carbonate of potash. The strychnine is precipita- 
ted from a solution of the salt by potash and ammonia. Chloride 
of potassium gives no precipitate. The salt prepared with tartaric 
acid contains 7-588 per cent, of water of crystallization ; the above 
formula requires 7*588. 
Bitartrate of Strychnine, C 44 H 24 N 2 O 4 , HO, C 4 H 3 5 +HO, 
C 4 H 2 O 5 -(-6HO, is the salt which separates when an exc e ss of 
tartaric acid is employed. The slender acicular crystals, which 
have a strong lustre even when dry, do not effloresce in the air, 
and are not very soluble in water ; potash produces no precipitate 
at first, but after a time causes a considerable opacity. A portion 
of the water of crystallization is expelled at 212°, but it does not 
part with the whole below 257° ; it may then be heated without 
further loss to 302°. The air-dried salt gave at 257°, 284°, 302°, 
the same amount of water, viz. 10* 11 per cent. 
Tartrate of Quinine, C 20 H 12 NO 2 , HO, C H 2 O 5 .— Quinine 
dissolves with difficulty in a solution of bitartrate of potash ; on 
evaporating the solution, a mixture of bitartrate of potash and a 
crystalline salt of quinine separates. When an acid solution of 
quinine is neutralized with potash, slender acicular crystals of tar- 
trate of quinine are obtained on evaporation, contaminated with 
the acid potash salt ; the mother-liquor finally deposits neutral tar- 
trate of potash. The salt, which quinine forms in preference with 
tartaric acid, is easily obtained by decomposing sulphate of qui- 
nine with neutral tartrate of potash, when a distinctly crystalline 
powder separates ; this has a bitter taste, a neutral reaction, is 
sparingly soluble in water, and melts, when carefully heated, 
