352 DR ANDERSON’S RESEARCHES ON SOME OF THE 
These results correspond exactly with the formula C,, H,, NO,,, as is obvious 
from their comparison with the calculated numbers given above. The atomic 
weight was determined by the analysis of its platinum salt, which is a very cha- 
racteristic compound, and which gave, as the mean of three experiments, 14:56 
per cent. of platinum, giving, for the atomic weight of the base, 464'8, and cor- 
responding perfectly with 463, the calculated number. 
IV. Properties of Narceine. 
Narceine crystallises in delicate needles which mat together into avery light 
and bulky mass, with a brilliant silky lustre. These crystals are always extremely 
white; indeed, narceine is remarkable for the facility with which it is obtained 
colourless, and while all the other crystalline principles of opium retain colour 
with considerable obstinacy, it may, with ordinary care, be obtained colourless by 
a few crystallisations, and in some cases is deposited in that state even from the 
highly-coloured mother liquor of the ammoniacal precipitate. In cold water it is 
sparingly, but in hot readily, soluble, and the solution on cooling becomes filled 
with a network of bulky crystals. In alcohol it is still more soluble, and is depo- 
sited from the hot fluid in needles which are generally shorter, thicker, and less 
silky, than those obtained from water. It is insoluble in ether. Ammonia and 
dilute solutions of potash and soda dissolve it in larger proportion than water, but 
the addition of a large quantity of concentrated potash to the dilute solution, pre- 
cipitates it, even in the heat, in the form cf an oily mass, which remains fluid for 
some time under the solution. The potash fluid. on standing for some time, depo- 
sits unchanged narceine, in the form of shining plates, which, by recrystallisation, 
again acquire the acicular form. It dissolves in dilute sulphuric, nitric, and hy- 
drochloric acids, without undergoing any change, and the solutions if sufficiently 
concentrated, deposit crystalline salts of narceine. 
When boiled with dilute nitric acid, the solution acquires a yellow colour, 
which on saturation with potash becomes reddish-brown, and the odour of a vola- 
tile base is immediately evolved. Concentrated nitric acid acts violently in the 
cold with copious evolution of nitrous fumes; after boiling for some time it gives 
on dilution a whitish precipitate, soluble in ammonia. and the fiuid contains oxalic 
acid. Strong sulphuric acid dissolves it in the cold with an intense red colour, 
which on the application of heat passes into a dark green. Strong hydrochloric 
acid dissolves it entirely, and without producing the blue colour which is de- 
scribed by PeLetier as characteristic of narceine. I did obtain a blue colour on 
one occasion, but it was when operating on a very small scale, and when the nar- 
ceine was not absolutely pure; but on repeating and varying the experiment in 
every possible way with the pure base, I have never again succeeded in producing 
it. Ihave been equally unsuccessful with a quantity of narceine which I obtained 
OO 
