
CRYSTALLINE CONSTITUENTS OF OPIUM. 357 
Some difficulty was at first experienced in the determination of the atomic 
weight of thebaine by the analysis of its platinum salt, until it was ascertained 
that that salt, when dried at 212°, retains two equivalents of water. The mean of 
three determinations of platinum gave 18°70 per cent. of the metal, and the calcu- 
lated result for the formula, 
Cy, H,, NO,, HCl, PtCl, + 2HO 
is 18:44. These results were also confirmed by the analysis of the hydrochlorate, 
of which the details will be given in their proper place. 
Properties of Thebaine. 
Thebaine crystallises from its alcoholic or ethereal solution in brilliant square 
plates with a silvery lustre. It is insoluble in water, but very soluble in alcohol 
and ether, especially on boiling. It dissolves readily in acids, and forms salts which 
are not obtained in crystals from aqueous solutions. It is insoluble in potash and 
ammonia. Strong sulphuric acid reacts upon it, and produces a deep-red colour, 
even when it is free from nitric acid. Concentrated nitric acid acts violently in 
the cold, with copious evolutions of red fumes, and formation of a yellow solution, 
which becomes dark coloured on the addition of potash, and evolves a volatile 
base. In hydrochloric acid it dissolves readily, and the solution on evaporation 
becomes dark coloured, and leaves behind a resinous matter, which does not dis- 
solve completely in water. Sulphuric acid, of specific gravity 1:300, dissolves it in 
the cold; and on gently heating a resinous or semisolid matter is thrown down, 
which, on boiling with water, slowly dissolves, and deposits, on cooling, a rather 
sparingly soluble salt, in microscopic crystals, which appears to be a product of 
decomposition, but of which I must defer the examination until I have obtained 
an additional quantity of thebaine. Chlorine and bromine rapidly decompose 
thebaine with the formation of resinous compounds. 
VIII. Salts of Thebaine. 
The small quantity of thebaine which I had at my disposal has prevented my 
extending the examination of its salts as far as I could have wished, and I have 
only examined such as are necessary for the determination of its atomic weight, 
and must reserve further details for a future paper. 
Hydrochlorate of Thebaine.—In order to prepare this salt, thebaine is mixed 
with a small quantity of strong spirit, and an alcoholic solution of hydrochloric 
acid gas is gradually added until the. thebaine is dissolved, an excess being care- 
fully avoided. On standing for some time, the hydrochlorate is deposited in 
extremely brilliant rhomboidal crystals, often of considerable size, or as a crys- 
talline powder if the solution be agitated. These crystals are purified by resolu- 
tion in absolute alcohol. They are extremely soluble in water, and the solution, 
on evaporation, gives only a resinous mass. In alcohol, especially if absolute, 
