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Selected Articles. 
from it be inhaled. One part by weight, of the powder, and 
two parts, by measure, of strong alcohol, are to be digested 
together in a gentle heat for seven days, and the tincture, 
while warm, is to be filtered. It is then to be reduced to the 
consistence of an extract by careful evaporation, at a low and 
well regulated temperature ; the object of this, is to prevent 
the destruction or expulsion of the active principle, which 
would very propably ensue, if the temperature employed were 
higher than barely sufficient to carry off' the alcohol. To the 
extract thus prepared, liquid ammonia is to be added, drop by 
drop, and well mixed with it, to precipitate the alcaloid : and in 
this part of the process, care must be taken that too much be 
not added, as in some instances the product appears to have 
been decomposed by inattention to this circumstance. It is 
difficult to give a precise rule as to the quantity ; but enough 
will have been added, if the extract give out the odour of am- 
monia, when stirred. 
-The mass now consists of impure aconitine, mixed up with a 
quantity of extractive and other matters, soluble in water ; 
and it may be taken up either with boiling alcohol, or sulphu- 
ric ether; or the soluble matter maybe removed by repeated 
washings with small quantities of cold water, which will leave 
the aconitine. This latter process, is the one we have gener- 
ally employed, and is performed by pouring a little water on 
the extract, and mixing them carefully together, then allow- 
ing the undissolved part to subside, pouring off the fluid, and 
repeating the operation, as long as any soluble matter is ta- 
ken up ; a quantity of light brown, or grey powder is left, 
which may be purified by subsequent solution in alcohol. This 
powder contains the active properties of the aconite, in a high 
degree of concentration. A grain of it was dissolved in a 
drachm of alcohol; and twenty drops of the solution put into the 
mouth of a guinea-pig, occasioned death in a few minutes. 
Other experiments have been performed; all of which prove 
the extreme energy of the substance. 
The second process consists in dissolving the alcoholic ex- 
tract, prepared as before, without the addition of the ammo- 
