
CRYSTALLINE CONSTITUENTS OF OPIUM. 349 
morphia is deposited. As the final result of these processes there is obtained a 
thick fluid, perfectly black, and of the consistence of tar, which formed the raw 
material for my investigation. 
I. Preparation of the Bases. 
The black mother liquor just referred to is diluted with water, and filtered 
through cloth in order to separate a small quantity of a brown flocky matter 
which is deposited. To the filtered fluid ammonia is added as long as a precipitate 
is obtained, and the whole is strained through a cloth filter, and the precipitate 
subjected to strong pressure. The precipitate thus obtained is of a rather dark- 
brown colour, and granular, but if left in the press for any length of time, is apt 
to run together into a resinous mass. It must, therefore, be rapidly removed 
before this change has taken place, broken up with the hands in a fresh quantity 
of water, and again expressed ; and this is repeated several times, until the fluid 
which runs off is no longer dark-coloured. The precipitate consists principally of 
narcotine, along with a considerable quantity of resin and a small quantity of 
thebaine; the filtrate contains narceine, and must be preserved for the prepara- 
tion of that substance. 
A portion of the precipitate is boiled with rectified spirit and filtered hot; on 
cooling, impure and very dark-coloured crystals of narcotine are deposited, which 
are collected on a cloth washed with a small quantity of cold alcohol and ex- 
pressed. The mother liquor of these crystals is then employed for the solution 
of a fresh quantity of the precipitate, the crystals obtained washed and expressed 
as before, and the operation repeated until the whole precipitate has been treated 
in the same way. The impure crystals of narcotine are then reduced to powder 
and rubbed into a paste with a concentrated solution of caustic potash. After 
standing for some time a large quantity of water is added, and the narcotine is 
_ deposited in a much less coloured state, the resinous impurities being retained in 
solution by the potash. The solution is then poured off, the precipitate of narco- 
tine washed with water, and finally purified by several crystallisations from boil- 
ing alcohol. 
The alcoholic solution from which the first dark-coloured crystals of narcotine 
were deposited, on being distilled in the water-bath, leaves behind a considerable 
quantity of a dark amorphous mass containing much resin mixed with a little 
narcotine and the whole of the thebaine present in the original precipitate. This 
_ residue is treated with hot dilute acetic acid, which leaves behind a large quan- 
_ tity of resinous matter, and dissolves the two bases, along with a certain quantity 
of resin. After several trials, I found that subacetate of lead afforded the best 
_ means of obtaining the thebaine in a state of purity from this solution. When 
 subacetate of lead is added to the acetic solution until the reaction becomes dis- 
