350 DR ANDERSON’S RESEARCHES ON SOME OF THE 
tinctly basic, the whole of the resin and narcotine are precipitated, while the the- 
baine remains in the solution. The fluid is filtered from the precipitate, and the 
excess of lead thrown down by means of sulphuric acid, the sulphate of lead 
separated by filtration, and ammonia added, when there is immediately obtained 
amore or less brown precipitate of thebaine, which is collected on a filter, washed, 
dried, and dissolved in boiling alcohol. The solution, which is generally very 
dark-coloured, becomes filled, on cooling, with flattened crystals of thebaine. 
The mother liquor is separated by expression, and the crystals, after boiling with 
animal charcoal and several crystallisations from boiling spirit, constitute pure 
thebaine. 
The mother liquor of the original ammonia precipitate, as has been already 
mentioned, contains narceine, for the separation of which I have found it most 
convenient to proceed in the following manner. A solution of acetate of lead is 
added to the fluid, and the dirty brownish precipitate which appears is separated 
by filtration through cloth. The excess of lead is removed by means of sulphuric 
acid, and the fluid filtered from the sulphate of lead, after being saturated with 
ammonia, is set to evaporate on the sand-bath at a moderate temperature. If 
the operation has been properly conducted, a film appears on the surface at a 
certain degree of concentration, and on cooling, a quantity of a crystalline matter 
is deposited in the thick brown mother liquor, which increases somewhat on 
being allowed to stand for some days. When this substance is collected on a cloth, 
and washed with a small quantity of water, it is sometimes obtained perfectly 
colourless at once, but more generally has a brownish colour. By farther evapo- 
ration of the mother liquor an additional quantity of crystals is obtained. The 
crystals are then boiled with a large quantity of water, and the solution, filtered 
hot, becomes filled on cooling with fine silky needles of narceine, while a large 
quantity of sulphate of lime and other impurities remain on the filter. The crys- 
tals of narceine have generally a slight shade of colour, and retain traces of sul- 
phate of lime, from which they are purified by solution in alcohol, boiling with 
animal charcoal, and again crystallising from water. 
Il. Narceine. 
Narceine was discovered by PELLETIER,* about the year 1832, and to his own 
and CouerBr’s} researches we owe all our present information regarding it. Both 
these observers have analysed it, but with results quite incompatible with one 
another, and from which they have deduced entirely different formule. Their 
analyses, when recalculated with the corrected atomic weight of carbon, gave the 
following results :— 
* Annales de Chimie et de Physique, vol. 1., p. 262. + Ibid., vol. lix., p. 151. 

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