CEPHAELIS IPECACU4NIIA' 
151 
*6f jtU The emetic properties ar^ destcQyed by boiling ; both \yater 
9od. spirit take up the emetic quality, but the latter mp^^ p^- 
pljeteiy than the former. ' ^ ^ . 
<^ Chemical Propertied, Analysis. S^c. We are mdebted 
tp Um. Majendie and Pelletier * for the discovery of the emetic 
priQciple in'ipecacuan ; from their experiments it appears, the active 
property resides in a peculiar principle, or vegetable alkali, which 
M Pelletier has obtained in an isolated state. To this substance 
they hav^ given the name of emetine: to obtain it, they digested 
ipecacuan root, first in ether and then in alcohol ; evaporated the 
alcoholic infusion to dryness, dissolved the residue m water, ^^nd 
dropped in acetate of lead ; the precipitate was then washed, 
diffused in water, and decomposed by a current of sulphureted 
hydrogen gas. Sulphuret of lead falls to the bottom and the emetine 
remains in solution ; by evaporating the water, the latter }s ,ob- 
tained. , , 
EMETINE. This substance, obtained according to the abpve pro- 
cess, is in the form of transparent brownish red scales. It has no 
smell, but a bitter acrid taste ; at a heat somewhat above that of 
boiling water, it is resolved into carbonic acid, oil, and vinegar r it 
affords no ammonia ; it is soluble in both water and alcohol, but 
not in ether, and uncrystalli.able. U is precipitated by a pro to- 
nitrate of mercury and corrosive sublimate, but not by tartar 
emetic. 
Pure Emetine. The emetme obtained by the process we haye 
described is not pure, but MM. Pelletier D""-, .^/.'"^'J 
chemical rese»rche. obtaioed this substance m a completely .solated 
"to obtain pure emetine, the powder of ipecacuan is digested 
in water with calcined magnesia ; the deposit is thrown on a filter, 
a ref ly washed with cold water, and dried. The enietine ,s tbeu 
aken up by alcohol. It may afterwards be combtned w,th an acid 
aid "he sail purified with animal charcoal; when the emetine is once 
Ir thrown down by magnesia, alcohol redissolves it ,n a colourle^ 
Emetine thus obtained is of a yellowish whtte. and pulverulent. 
' 'only effect of air is to colour it slightly It is httle so u le .n 
cold water, and somewhat more so in hot. t fuses ' 
and is very soluble in alcohol, but not in ether or od . I' -^blgh y 
lalin . hough acids saturated with it do not afford crystalhzable 
Vide Ann. de Ghim. et de Phys. iv. 172. 
