Active principles of Sarsaparilla. 41 
is not combined, but is merely retained by it. M. Soubeiran 
who was much interested in these investigations, suggested 
the following method of proving that salseparine does not 
combine with acids ; he crystallized it in alcohol containing 
an excess of sulphuric acid, placed the crystals in a tube 
closed at one end, and covered with cotton ; he then poured 
sulphuric ether on the cotton, this, in traversing the salsepa- 
rine, carried off all the sulphuric acid with it. This experi- 
ment succeeded perfectly. 
Sulphuric acid exercises a peculiar action on salseparine. 
If it be added in a concentrated state to salseparine, drop by 
^drop, this substance becomes of a dark red colour, which 
gradually changes to a violet, and finally to a pale yellow. 
A solution is obtained, from which, on the addition of cold 
water, the salseparine is precipitated, and the yellowish co- 
lour disappears. Hence it is evident the salseparine is unal- 
tered by the acid, notwithstanding the change of colour. 
Cold water does not precipitate it from its solution in diluted 
sulphuric acid. 
The action of nitric acid on this substance, differs from 
that of sulphuric. When concentrated, it dissolves it at the 
ordinary temperature, but it alters a small portion of it ; this 
altered part becomes yellow. The nitric solution gives a 
white precipitate on the addition of water, formed almost en- 
tirely of unaltered salseparine. 
Hydrochloric acid also dissolves salseparine, and on eva- 
porating the solution affords fine crystals, in fact all the acids 
act alike in this respect, to a greater or less degree. 
Jour, de Pharm. 
Vol. I—No. 1 
6 
