On the preparations of Opium. 
13i 
augmented by the application of heat, which induces a kind 
of combination between the principles ; third, that by redis- 
solving the extract of opium in a large quantity of cold wa- 
ter, and afterwards concentrating the solution, at each suc- 
cessive repetition of the process, a certain quantity of fatty 
matter, resin and narcotine is eliminated. On the other hand, 
the volatile principle must be in a less quantity in extracts 
made by long digestion, than in those made in the usual man- 
ner in a water bath, either from its being driven off, or from 
its having suffered an alteration. 
The chemical composition of these extracts, therefore, 
although very analogous, is not precisely identical. 
The extracts prepared according to the Batavian Phar- 
macopoeia, or to the formulas of Lemery and Quincy, also 
appear to me, must contain all the principles found by analy- 
sis in the watery extract of opium, and in the same state, 
since there is probably no reaction between the alcohol and 
these principles. The process of the Batavian Pharmaco- 
poeia, which orders the opium to be washed with alcohol, to 
dissolve the resin, before it is treated with water, must ne- 
cessarily also dissolve a certain portion of its active princi- 
ples ; whilst in the extract of Lemery, prepared by treating 
opium with alcohol and water successively, the caoutchouc, 
bassorine, earthy matters and vegetable impurities only are 
separated. The first of these processes may in reality fur- 
nish a more active extract than that made with water alone, 
if it be true that cold alcohol takes from the opium a propor- 
tionally larger quantity of fatty and resinous matter than of 
; the active principles. The second must afford, as regards 
its bulk, an extract less rich in acid meconates of morphine 
and codeine, meconine and narceine, as it contains all the 
resin and fatty matter. At the same time, the greater pro- 
portion of narcotine in this extract may, in some degree, 
compensate for this diminution of the other principles. 
The extract by wine, proposed in the codex of« 1758, ap- 
pears to have much analogy to that of Lemery ; but the ad- 
dition of the constituent principles of the wine, principles thaft 
must be considered not only as regards the reaction they 
