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BRITISH PHARMACEUTICAL CONFERENCE. 
Blight loss may be expected when the iodide transferred to the silver bottle 
arrives at its appointed time for reduction. The loss, however, is so small as 
not to be worth consideration when the process is followed on an experimen¬ 
tal scale only. In the large way I should treat it first with sulphide of am¬ 
monium, then with acetate of lead. It is necessary to use both, as I find the lead 
alone removes only half the iodine, the remaining half interfering greatly with 
the subsequent operations. But by first removing the mercury as sulphide, and 
then using the lead, the liquid is completely cleared of that troublesome element. 
I could not at first understand the product I obtained by adding ammonia to 
the liquid containing the aconitine in the presence of iodine, and washing with 
sulphuric ether, nor at all comprehend why an alkali of some sort did not 
precipitate the alkaloid from such a solution. It appeared, however, that the 
hydriodate of aconitine is not decomposable by alkalies, and that when such 
a mixture is shaken with abundance of sulphuric ether the hydriodate in a 
pure state is the only thing taken up. An additional embarrassment is felt 
by the inutility of shaking the sulphuric ether holding the hydriodate in so¬ 
lution with acidulated water with the view of recovering the alkaloid as a 
muriate or nitrate. 
To return from my digression. The liquid filtered from the iodide of silver 
contains now nitrates of mercury, of silver (in minute quantity), and of the 
alkaloid, and the latter may at once be obtained in a pure state by adding an 
excess of carbonate of potash, and washing two or three times with ether. 
But I prefer first removing the mercury by sulphuretted hydrogen, as it 
renders the washing with ether so much easier and neater. The ether 
evaporated or recovered by distillation leaves a residue of a pale brown 
colour, which is partly crystalline, partly translucent like a fused resin, and ex¬ 
hibits a strongly alkaline reaction. On the average I obtained of this rather 
more than ten grains per pound of root, or, making allowance for that re¬ 
maining in the marc, twelve grains per pound. 
The aconitine is then dissolved in water with a very slight excess of nitric 
acid, filtered, and set aside to crystallize. This it commences to do at once, 
one-half or thereabout of the aconitine being so obtainable. I find it crystal¬ 
lizes much more easily as nitrate than as sulphate or hydrochlorate. The 
crystalline form of the nitrate appears to be the rhombic prism, commonly with 
dihedral summits. They readily effioresce when heated, losing their trans¬ 
parency, as is the case with the specimen exhibited, which was accidentally 
exposed to the direct rays of the sun. The nitrate does not dissolve readily 
in cold water; from its solution in hot water it crystallizes with unusual 
facility. 
Tried on the eye of a cat, it produced during the first half-hour no efiect 
beyond irritation of the neighbouring membranes; after an hour it caused 
permanent dilatation of the pupil. Its colour-test reactions are neutral, no¬ 
thing marked about them. It is precipitated by bichloride of platinum. 
From this nitrate the pure crystalline alkaloid is obtainable by the ordinary 
method—precipitation by ammonia and solution in spirit. It may be ob¬ 
jected that this crystalline body is not aconitine. I can only say that it pos¬ 
sesses in a high degree the poisonous properties of the root; for some years 
ago, not being in a position to repeat the experiment quoted by Orfila from 
Matthiolus, viz. the administration of Aconite to four highw'aymen,—the 
medisBval response to the proverb “ Fiat experimentum in corpore vili,”—I 
took a dog of medium size, and gave him Jjjth of a grain of these crystals. 
He vomited within an hour after, foamed at the mouth, was purged, with 
great apparent irritation of the anus, but recovered sufficiently to have a 
second dose of tjV grain a few days after, or the next day, I forget which. This, 
notwithstanding his great efibrts to remove the poison from his stomach by 
