CRYSTALLINE CONSTITUENTS OF OPIUM. 363 
by filtration, and the evaporation repeated until as much as possible is separated. 
The remaining syrupy fluid, which contains a large quantity of carbonate of potash, 
is then boiled with successive quantities of rectified spirit, as long as anything 
is extracted, the alcohol is distilled off, and the residue mixed in the ‘cold 
with an excess of hydrochloric acid. A precipitate makes its appearance, with 
characters differing according to the substances which happen to be present, and 
is sometimes crystalline, and sometimes a syrupy mass, which passes into the 
crystalline state on standing.. This precipitate contains opianic acid, hemipinic 
acid, and in some instances two other substances, to one of which I give the name 
of Opiany], and to the other that of Hydrate of Opiany]. 
Opianyl.—This substance is only formed when the oxidation has been extremely 
gentle, and, though repeated trials have been made, it has been found impossible 
to moderate the action in such a way as to produce it at will. In order to obtain 
it in a pure state, the precipitate by hydrochloric acid, which has just been 
referred to, is dissolved in a large quantity of boiling water, and the solution 
allowed to cool. A crop of crystals is deposited which consists of opianyl along 
with some opianic acid, if the quantity of water employed have not been suffi- 
ciently large. These crystals are purified by solution in boiling water and in 
alcohol. In one instance opianyl was obtained along with hemipinic acid, and 
with only traces of opianic acid, and in that case its purification was conveniently 
effected by dissolving in boiling water, precipitating hemipinate of lead with a 
solution of neutral acetate of lead, washing the precipitate in boiling water, and 
evaporating to a small bulk, when opianyl was deposited in colourless crystals, 
which were purified by solution in boiling water. 
Opiany] is thus obtained in long delicate needles, which, when pure, are per- 
fectly colourless. They are sparingly soluble in cold water, and more soluble in 
boiling. When a quantity is boiled with a smaller amount of water than is re- 
quired to dissolve it, the residue melts under the fluid; but it does not fuse at 
_ 212° in the water-bath, requiring, when dry, a temperature of 230° to produce its 

fusion, and, on cooling, it resolidifies at about 220°. In alcohol it is easily soluble. 
Ether takes it up readily, and, on evaporation, deposits it in brilliant groups of 
radiated needles. Concentrated sulphuric acid dissolves it in the cold, and forms 
a perfectly colourless solution, which, when heated, becomes of a beautiful and 
characteristic purple colour. Nitric acid, of specific gravity 1:400, dissolves it 
in the cold, and on dilution with water it is deposited unchanged. By boiling, 
red fumes are evolved, and the fiuid no longer gives a precipitate on being 
diluted. Hydrochloric acid dissolves it in somewhat larger quantity than water. 
Solutions of potash, soda, and ammonia, do not dissolve it more abundantly than 
water. It is incapable of forming compounds with the metallic oxides, and con- 
tains no nitrogen. 
VOL. XX. PART Ill. eee 
