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Selected Articles. 
2d. Of acetic acid, produced, in all probability, by the 
presence of a certain proportion of sugar in the juice. 
3d. Of an organic salt, having a base of magnesia, the acid 
united with it appearing of a peculiar character, (manihotic 
acid.) 
4th. Of an acrid, bitter principle, irritating the throat, and 
very soluble in water and alcohol. 
5th. Of a brown compound substance, soluble in the same 
fluids, having an osmazomic smell and taste, and mixed with 
traces of sugar. 
6th. Of some salts, especially phosphate of lime. 
7th. Of amylaceous fecula and glutine, forming an insolu- 
ble deposit in the unfiltered juice. 
Journ. de Pharm. 
ART. XXXI.— NEW METHOD Of OBTAINING CANTHARIDINE. 
By M. Thierry. 
M. Robiquet was the first chemist that isolated the vesica- 
ting principle of cantharides, or at least that which enjoys 
this property in the most marked manner. He gave it the 
name of cantharidine, and pointed out its distinguishing cha- 
racters : but his mode of extraction is long, complicated, and 
gives but a trifling product. For a long time past I have en- 
deavoured to extract cantharidine by a more simple and ex- 
peditious procedure, when at last I hit upon it by accident. 
About ten years since I prepared vesicating plaster, which, 
not acting as expeditiously as I wished, to render it more active 
I moistened its surface with an etherial tincture of cantharides 
which had been made for some time. Some hours afterwards 
on examining the plaster, I was surprised to find its surface 
covered with crystalline scales. 
Having to prepare cantharidine by the method of M. Ro- 
biquet, and having obtained a very small quantity, I reflected 
on what other means might be employed, and recollected the 
above occurrence, which I determined to take advantage of. 
