1338

ELEMENTS OF MATERIA MEDICA.

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alkali ( aconitina ) in aconite. Their statement was confirmed, m '^by Pallas (op. supra cit.), and, in 1832, by Geiger and Hesse (Jo' urn ^ aChim.-Med. x. 464). Peschier also asserted that aconite containpeculiar acid ( aconitic acid). His assertion has been substantiatei <

L. A. Buchner, jun. ( Pharrn. Central-Blatt. fur 1838, S. 439)* . ^chemists have admitted the existence of a volatile acrid princip 1aconite; but it has not hitherto been isolated.

esents

the

1. Aconitina (Aconite). —As prepared by Mr. Morson, this substance p res j uS

following- properties:—It is a white, odourless solid, either dull and amorp 11somewhat sparkling, and apparently crystalline. As it is usually described ^^jcro-uncrystallizable, I have carefully examined a supposed crystalline mass with the . (eSscope, but I could not detect distinct crystals. The fragments appeared like th' n F- orl ijof chlorate of potash, and, though they varied greatly in shape, the triauguw |, er .seemed predominant. Heated in a tube, aconita readily fuses, and forms acoloured liquid ; and at a higher temperature decomposes. It is not volatile. g0 lubl eon platinum, or over a spirit-lamp, it is speedily and entirely dissipated. M 1S * n0 uia-iu alcohol, ether, and the acids. From its acid solution it is precipitated by anl ofA minute portion of it mixed with lard, and applied to the eye, causes contro. ^jjlithe pupil, as I have repeatedly seen. Geiger and Hesse state that the aconim*® r fulthey obtained produces dilatation of the pupil. Mr. Morsou’s aconitina is so ]j° nl0 stthat one-fiftieth of a grain has endangered the life of an individual. It > 3 1virulent poison known, not excepting- hydrocyanic acid. ,

2. Volatile Acrid Principle. —This, though admitted by several chemists, has "0 , 0 {isolated. Geiger ( Pharm. Central-Blatt. fur 1831, 491) submitted the / re _ ^ a cri<i

Aconitum Napellus , with water, to distillation, and obtained a liquor bavin,, tu .»taste, an uupleasant odour, and whose emanations affected the eyes. May A v ju£volatile principle be the product of the decomposition of the aconitina? The jo ^ o0 ticircumstances favour this suggestion :—1st. The fresh herb and root have lij“® aC „iii"2dly, the local effect of aconitina is similar to that of the root and leaves ; 3d „,p0'tina, when mixed with the other constituents of the plant, readily undergoes u ^ jt;sition, so that considerable nicety of manipulation is required in the extractionand Mr. Morson tells me he has sometimes failed to obtain it. g f a )s o*

3. Aconitic Acid. —In the evaporation of the juice of aconite, octahedral cl 7 ■ th eaconitate of lime are frequently deposited. From these L. A. Buchner obta*acid. The acid is scarcely crystalline, merely forming warty elevations. Ij j . a iidpermanent in the air, odourless, very sour, and is very soluble in water, alcp ’ ptether. When heated it fuses, hut at the same time undergoes decomposite ’ p, s i'does not yield fumaric acid. From the latter acid itis distinguished by itsgrea - e \&-bility and solubility ; from maleic acid by its forming indistinct crystals, and ning fumaric acid by heat. The anhydrous acid, as found in aconitate 0consists of C* Hi 03.

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Physiological Effects.— Hitherto I have met with no cm

accurate account of the effects of aconites, and some of them IT

to me to have been entirely overlooked. oi

(a.) On animals. —If a small quantity of the soft alcoholic ext ‘ ^

the root of aconite be introduced into a wound (as into the cavity ^

peritoneum) in a dog, it usually causes vomiting (sometimes of a

raceous character), diminishes the force of the circulation, weake^ pi

muscular system so as sometimes to cause the animal to

walking, and destroys common sensibility or feeling, without pg-

stupor. A dog under the influence of not too strong a dose, no pis

times follow its owner around the room, recognize him by wagg 1 ^ v jtk

tail when called, and yet be totally insensible to pinching, prickmg W

needles, &c. Convulsions do not usually occur until a short P el

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fore death, and they are then commonly slight, and rather to bespasmodic movements. I have repeatedly demonstrated these e

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