314 poisons: their effects,and detection. [§ 373 * 
again. It is best to extract the liquid for morphine at least thrice, and 
to operate with both the solution and the amyl hot. The decinormal 
acid liquid is made slightly alkaline with ammonia, and allowed to stand 
for at least twelve hours ; any precipitate is collected and washed with 
ether, and then with water ; the alkaline liquid from which the mor¬ 
phine has been separated is concentrated to the bulk of 5 c.c. on the 
water-bath, and again allowed to stand for twelve hours ; a little more 
morphine may often in this way be obtained. 
The authors in some test experiments, in which w.eighed small 
quantities of morphine (60-80 mgrms.) were dissolved in a little deci¬ 
normal sulphuric acid, and added to large quantities of urine, found the 
process given to yield from 80 to 85 per cent, of the alkaloid added, and 
it was always recovered in fine crystals of a slight brown tint, which 
responded well to tests. 
Various other methods were tried, but the best was the one given ; 
the method not only separates the alkaloid with but little loss, but also 
in a sufficiently pure state to admit of identification. 
From the tissues the alkaloid may be dissolved out by the general 
method given at p. 250, and the ultimate aqueous solution, reduced to 
a bulk of not more than 25 c.c., treated by the ethereal solvents in the 
way just described. 
§ 373. Narcotine (C 22 H 23 N0 7 ) crystallises out of alcohol or ether in 
colourless, transparent, glittering needles, or groups of needles, belong¬ 
ing to the orthorhombic system. 
It is only slightly soluble in boiling, and almost insoluble in cold 
water. One part requires 100 parts of cold, and 20 of boiling 84 per 
cent, alcohol; 126 parts of cold, 48 of boiling ether (specific gravity 
0-735) ; 2-69 parts of chloroform ; 400 of olive oil; 60 of acetic ether ; 
300 of amyl alcohol; and 22 parts of benzene, for solution. The neutral 
solution of narcotine turns the plane of polarisation to the left, \a\r= 
130-6° ; the acid solution to the right. Narcotine has no effect on red 
litmus-paper. 
Narcotine gives no crystalline sublimate ; its behaviour in the sublim¬ 
ing cell is described at p. 263. Its melting-point, taken in a tube, is 
about 176°. 
Behaviour of Narcotine with Reagents. —Narcotine, dissolved in 
dilute hydrochloric acid, and then treated with a little bromine, gives a 
yellow precipitate, which on boiling is dissolved ; by gradually adding 
solution of bromine and boiling, a fine rose colour is produced, readily 
destroyed by excess of bromine. This is perhaps the best test for the 
presence of narcotine. Concentrated sulphuric acid dissolves narcotine ; 
the solution in the cold is at first colourless,"after a few minutes yellow, 
and in the course of a day or longer the tints gradually deepen. If the 
solution is warmed, it first becomes orange-red, then at the margin 
