Symptoms in Man.—Some interesting information on the characters and properties of this plant is contained in the Medical and Physical Journal. Among other cases the writer relates those of two ladies who ate a little of it in a sallad instead of parsley, and who were soon seized with nausea, vomiting, headache, giddiness, somnolency, pungent heat in the mouth, throat, and stomach, difficulty in swallowing and numbness of the limbs.[[2244]] Gmelin has related the case of a child, who died in eight hours in consequence of having eaten the æthusa. The symptoms were spasmodic pain in the stomach, swelling of the belly, lividity of the skin, and difficult breathing.[[2245]] In two children who recovered, the chief symptoms at the height of the poisoning were complete insensibility, dilated, insensible pupil, and staring of the eyes. In one of them there was also frequent vomiting, in the other convulsions. The treatment consisted in the administration of milk, sinapisms to the legs, and cold spunging with vinegar.[[2246]]
CHAPTER XXXV.
OF THE NARCOTIC RANUNCULACEÆ.
The greater part of the poisons belonging to the Natural Family Ranunculaceæ are acrid only in their action, and have been already taken notice of among the irritants. Two only are yet known to possess narcotic properties, namely, monkshood, and black hellebore. The latter is a true narcotico-acrid. The former has till lately been always considered so; but its acrid properties seem doubtful or feeble, while its action on the nervous system is most intense.
Of Poisoning with Monkshood.
Monkshood, the Aconitum napellus of botanists, is an active poison, and has commonly been considered a true narcotico-acrid. But its effects have been hitherto much misunderstood. It has been used for criminal purposes in Ireland; and in 1841, a woman, M’Conkey, who was executed there for poisoning her husband, was proved to have administered this substance [see p. [61]]. The root of another species, the A. ferox, is well known to be in common use as a poison, under the name of Bikh, in Bengal, and Nabee, in the Madras Presidency.
The toxicological history of the genus, and of this species in particular, has been rendered complex and obscure, by the extreme difficulty of distinguishing accurately the several species from one another. The whole genus, now a numerous one, is generally conceived to be eminently poisonous. But from some observations of my own, as well as an elaborate inquiry, not yet made public, by Dr. Alexander Fleming,[[2247]] a recent graduate of this university, I am inclined to think that this is a mistake, that the poisonous species are not numerous, and that many aconites are inert, at least in this climate.
The A. napellus, a doubtful native of Britain, and the most common species in our gardens, shoots up annually a leafy stem from a black, tapering, spindle-shaped root. The stem, which is from two to five feet high, ends in a long dense spike of fine blue flowers; and when the seeds ripen in autumn, it dies down, and the root also shrivels and perishes. But in the spring, while the stem is rising, one or more tubers form near the crown of the root; each tuber quickly assumes the spindle-shaped form of its parent, but has a light brown, instead of a brownish-black tegument; and when the plant is in flower, the new tuber, destined for the root of next year’s plant, is as large as the parent one, firmer, more amylaceous, and not so apt to shrivel in drying. This mode of propagation has led some to describe the root erroneously as sometimes palmated. Dr. Fleming considers the young, full-grown tuber to be the most active part of the plant; but the root of the existing plant, the leaves, and also the seeds, are highly energetic; and every part is more or less so.
Every part of the A. napellus, but especially the root, affects remarkably the organs of taste, producing a very singular sense of heat, numbness, and tingling of those parts of the mouth to which it is applied. Dr. Fleming has ascertained, that this peculiar taste, or rather sensation, is a property belonging to the narcotic principle of monkshood, and that in all probability it is a measure of the activity of the plant as a poison. It is most intense in the root, next in the seeds, and next in the leaves before the flowers blow. Geiger first ascertained, and I have since observed, that the sensation thus occasioned by the leaves diminishes in intensity as the flowers expand, and almost disappears when the seeds ripen. Contrary to what has been often stated, it is not diminished by drying the leaves, even with the heat of the vapour-bath. Nor is it materially lessened by time, if the dried leaves be preserved with care; for I have found it intense after six years. Geiger observed some years ago, that several species or varieties do not possess it. I have ascertained that A. napellus, sinense, tauricum, uncinatum, and ferox, possess it intensely, A. schleicheri and nasutum feebly, A. neomontanum very feebly; all of which are therefore probably poisonous, in proportion to the intensity of their taste. A. ferox, well known as a deadly poison in the East, and undoubtedly the most virulent of all the species, produces by far the most intense and persistent effect on the mouth of all the species I have had an opportunity of examining. Those which do not produce it at all, at least in this climate, are A. paniculatum, lasiostomum, vulparia, variegatum, nitidum, pyrenaïcum, and ochroleucum. It would be premature to say that all these species are inert; but I suspect they are: and, at all events, I have ascertained that the leaves of A. paniculatum, although the officinal species recognised in the London Pharmacopœia, are quite inactive in this climate; and Dr. Fleming has found the root inert in medicinal doses of considerable magnitude.
The properties of monkshood have been traced by Geiger and Hesse to a peculiar alkaloid, named aconitina: which is white, pulverulent, fusible, not volatile, soluble in ether and alcohol, sparingly so in water, and capable of forming crystallizable salts with acids. It produces most intensely the peculiar impression caused by the plant on the mouth, tongue, and lips; and it is a poison of tremendous activity, probably indeed the most subtle of all known poisons. Although not a volatile principle, it has been supposed peculiarly liable to decomposition by heat, at least in its natural state of combination in the plant or its pharmaceutic preparations. This opinion is founded on the uncertainty of the medicinal action of the common extract of the shops, and on the results of experiments on animals by Orfila.[[2248]] In one experiment he found that half an ounce of the extract of the Parisian shops had no effect at all on a dog, while a quarter of an ounce killed another within two hours. Careless preparation may account for such differences; but at the same time an error in choosing the species of plant is an equally probable explanation. The properties of monkshood appear to me to resist a heat of 212°, either in drying the plant or in preparing an extract from it.
The medico-legal chemistry of monkshood has not been studied. If any of the suspected matter be obtained in a pure state, its best character is its remarkable taste; to which I have found nothing exactly similar in the numerous trials I have made with other narcotic and acrid plants. A complex substance, such as the contents of the stomach, or vomited matter, should be evaporated over the vapour-bath to the consistence of thin syrup, and agitated with absolute alcohol. The filtered alcoholic solution being then evaporated, the extract may be subjected to the sense of taste.