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taking the deadly potion. A dose of this magnitude indeed, seems usually to prove fatal within an hour. A man, who was seen to pass the mission-house to the habitation of the priests, where he was compelled to take nineteen pounded seeds in a draught, was carried back, a stiffened corpse, in an hour afterwards. The only chance of life is an early attack of vomiting. In a courageous attempt by Mr Waddell to persuade king Eyo to abandon the trial of several people who were charged with slaying a man of family by witchcraft, a woman who had taken ten seeds was seized with vomiting while Mr Waddell was engaged in an altercation with the king; upon which she was immediately claimed by the missionary as innocent by their law, and was saved. Sometimes the horrible trial is undergone on the great scale, when a chief of rank is thought to have died suspiciously. In 1834, when a noted chief man called Duke Ephraim died, all his relatives and slaves, to the number of fifty, were condemned to undergo the ordeal, and no fewer than forty of them died. Among the documents put into my hands by Mr Waddell was a journal of this transaction, kept at the mission by a native convert in his broken English, of which the following extract is a graphic specimen :

"Old Calabar, October 14, 1834.-Ephraim Duk died in five o'clock this evening, and put him for grown next morning.

"16 October 1834. This morning all country and Calabar come, and we go for Mr Young, and stop little, not long, after that we go for Duk Palaver House, with all country and our people, about the Duk Ephraim sick, and we go in for his yard; so all our people chop nut. The name of them: Erim Cooffee Duk chop, dead. His son chop, no dead. Orrock Cooffee, and two his son, dead. Cooffee Copper, dead. Egbo Esham, dead. Egbo Young Egbo, dead. Bashie Archiebong Egbo Duk, dead. Erim Odoor, mother dead. Erim Egbo Duk Ephraim Otto, dead. Young Old Archiebong, dead. Otto Ercanam, dead. One Otto slave, dead, for street. Egbo Eshen, mother, dead to night.

“Ditto 17.—5 Duk wife chop nut this morning. All dead, etc."

Here other names follow; and so the entries go on day by day until forty of these cold-blooded murders are recorded.

I have received a few days ago some additional particulars respecting the uses of this poison from Dr Daniell, who resided for some time in Calabar, and, by his influence with Eyamba, the king of the country, was allowed to witness scenes which are usually forbidden to Europeans. This gentleman confirms the testimony of the missionaries as to the deadly nature of the poison, and says it is used not only as an ordeal-poison, but likewise often for despatching the numerous wives and slaves who are buried on the occasion of the funeral of men of consequence.

The ordeal-nut of Calabar, called Esére by the natives, is a leguminous seed or bean, about the size of our garden-bean, but thicker. According to one account I have received, it is not produced in the Calabar district, but is floated down the river from the upper coun

7. This is possible, for it floats in water; but it is not very likely. ccording to information communicated to me by Dr Daniell, it is stated to him by the natives to grow in marshy places near ttarpah and Old-town in Calabar; and the Rev. Mr Waddell was formed that the plant is everywhere destroyed by order of the ng, except where it is preserved for supplying the wants of juste; and that the only store of seeds is in the king's custody.

The seed is, I apprehend, quite unknown in Europe. Of several ninent botanists, including Mr R. Brown, to whom I have shown it, > one has been able to recognise it as a known species. In order to escribe it, it has been cultivated at my request by my colleagues, 'rofessor Syme and Dr Balfour, and both have succeeded. It proves be a perennial creeper, of the natural family, Leguminosa, and losely resembling a Dolichos. It has a large root-stock. The fresh ant has a heavy, strong smell, after being some time cut. Though vo years old, it has not yet flowered; and, like other perennial reepers, it may require to form wood for several years longer before bears flowers. I am therefore unable to describe it farther, or to ame it.

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It has a hard, brittle, ligneous tegument, rather rough, and of a rownish-crimson or pale chocolate-brown colour; but many specinens are ash-grey, apparently from slight mould. The kernels, which weigh from 36 to 50 grains, are always in good preservation, and never injured in the slightest degree by insects-a rare occurtence with tropical seeds. They are white and hard, but may be thewed; and they have the taste of the eatable leguminous seeds, without bitterness, acrimony, aroma, or any other impression on the organs of taste; in fact, they are scarcely, if at all, distinguishable in taste from a haricot-bean. This is a formidable peculiarity, were it possible for the seed to become a familiar poison in Europe. So far as I know, the property in question is peculiar to it, for all other poisonous seeds of the Leguminosa, with which we are sufficiently acquainted, are bitter. The blandness of its taste is indeed so unusual a character that I was at first misled, and imagined that I had probably got a wrong and harmless seed; but I soon found that I was much mistaken.

I began a chemical examination of it, with the hope of separating an active proximate principle, which assuredly must exist in it, and will prove to be a poison of appalling subtilty. But with my limited materials success was unattainable; for leguminous seeds are difficult to analyse; and in this instance there is the additional obstruction, that at every stage the want of any marked sensible ⚫ property makes it necessary to perform a physiological experiment on one of the lower animals, otherwise we may follow a wrong direction in the search. All I can say is, that the seed, like others of its natural order, contains much inert starch and legumin, and 1.3 per-cent of fixed oil, also probably inert; that its active properties may be concentrated in an alcoholic extract, which constitutes 2.7

per-cent of the seed; and that this extract does not yield a vegetable alkaloid by the more simple of the ordinary methods of analysis.

I shall now proceed to mention what I have observed of the effects of the ordeal-bean on the animal body. These are interesting, energetic, and in some respects peculiar, as it seems to affect directly and violently the functions of the heart, and the exercise of volition over the muscles.

When a poison impresses powerfully both the circulation and some function or functions of the nervous system, it is a matter of great nicety to eliminate the true phenomena, especially by observation upon the lower animals alone.

We know that some poisons, such as strychnia, and the various seeds and barks which contain it, cause, by direct irritation of the spinal chord, violent tetanic spasms of the voluntary and respiratory muscles, without impairing sensation, or enfeebling the heart, or clouding the mental faculties; and thus they occasion death by convulsive arrestment of respiration. Others, such as the urari poison, and conia, or hemlock from which it is derived, cause, by direct exhaustive action of the spinal chord, the opposite state of paralysis of the voluntary and respiratory muscles, but still without influencing the heart, or sensation, or the mental powers; and so death arises in their instance from arrestment of respiration, by simple paralysis of the muscles which maintain it. Others again, such as atropia, or belladonna, the plant which yields it, principally assail the functions of the brain, at first combining stimulus of some with exhaustion of others in the most singular and often grotesque concatenation, but inducing at last a state of profound coma, and as the result of this a universal muscular paralysis; and thus death ensues, equally as before, from arrestment of the breathing, not however by direct action on the origin of the nerves which govern the muscles of respiration, but indirectly, through an influence on the cerebral functions, exactly as in ordinary apoplexy. We can likewise conceive a poison to possess only a simple and direct action upon the heart, producing exhaustion of its irritability, paralysis, and consequently death, by arrestment of the circulation; but no such poison is yet known. These are all instances of simple action on a single vital function. But many poisons exert a more composite action. Some, such as nicotina, and its source, tobacco, produce paralysis of the heart, and also a narcotic action on the brain. Others, such as foxglove, and in all probability its active proximate principle, digitaline, not only possess this double action on the heart and brain, but likewise powerfully irritate the kidnies. Others, such as hydrocyanic acid and picrotoxa, the active constituent of cocculus-indicus, exhaust the functions of the brain, so as to induce coma, and at the same time irritate the spinal chord, so as to excite convulsions; and thus, here again we have death produced by arrestment of the breathing, indirectly through the brain, but concurrently with direct spinal

irritation. In others, such as aconitina, and its source, monkshood, there is a singular combination of exhaustion of the heart's irritability, and of common sensation, but without any influence on the voluntary muscles, or on the mental faculties; and death arises by arrestment of the circulation.

It is easy to see,-on considering attentively what must be the manifestations of these various actions, both simple and compound, but especially the latter, that extreme difficulty will often occur in seizing and rightly comprehending the facts, above all when the succession of phenomena is swift, and when the subject of observation is one of the lower animals, which cannot adequately express by external signs the varying influence of agents on sensation and the other cerebral functions.

Hence it arises that many erroneous conclusions have been come to regarding the action of our most potent and interesting poisons. Take for example hemlock. This formidable poison was long supposed to cause death by coma, that is, a narcotic action on the brain. But I have shown in a paper read before this Society in 1836, that the mode of death is really by paralysis of the muscles and arrestment of respiration, through an exhaustive influence on the spinal chord. And it is easy to see where the source of error lay. For, when the muscles are paralysed, sensation and the mental faculties will seem to a common observer to be paralysed also; because the animal mechanism for producing expression is at rest.-It appears that many persons think it an easy task to investigate experimentally the physiology of poisoning. But they are assuredly mistaken. A long apprenticeship must be passed before any one can observe with accuracy the phenomena of the action of poisons.

These cautions are prefatory to the remark, that it is a matter of great nicety to apprehend the deceptively simple manifestations of the action of the ordeal-bean on the lower animals. Scarcely do signs of uneasiness appear after a fatal dose has been given, when the animal becomes in quick succession languid, prostrate, flaccid, immovable; respiration, now faint, speedily ceases; and death is complete. It may thus appear to die insensible and comatose. But that is not the case. So long as the power of expression remains, amidst the swiftly advancing languor, signs of sensation may be elicited. Or we might infer from the phenomena that it dies of paralysis of the voluntary and respiratory muscles. But this too is in all probability not the fact. For, on dissection immediately after respiration ceases, the heart is found in a state of paralysis; and it is evident that a quickly increasing paralysis of the heart not only explains the mode of death, but might likewise account for the antecedent muscular weakness and flaccidity.

These effects were well exemplified in the first experiment I tried, when twenty-one grains of fine powder, made into an emulsion with two drachms of water, were secured in a cavity in the subcutaneous cellular tissue of the flank of a rabbit. For three minutes there was

no appreciable change. But the animal then evidently became weaker, especially in the hind legs. Its feebleness quickly increased, and was attended with slight irregular twitches of the muscles of the trunk and extremities, and occasional twitching of the head backwards. But sensation remained; for the animal struggled a little when held up by the ears, and resisted attempts to shove it from behind. In four minutes, when put upon the side, it lay in that position; which the rabbit always vehemently resists so long as it is able. The trunk and extremities immediately afterwards became quite flaccid. Respiration ceased in five minutes certainly; probably indeed sooner; but the precise time could not be fixed, owing to continuance of slight muscular twitches. The chest being immediately opened, the heart was seen pulsating slowly, feebly, and inefficiently for ten minutes; and when its cavities were then perforated, the left side gave out a much brighter blood than the right, showing that the circulation, owing to paralysis of the heart, had not been maintained after respiration had ceased. The muscles of voluntary motion contracted at this time vigorously under the stimulus of galvanism, and continued to do so twenty-five minutes after death.

The same remarkable properties are possessed by the alcoholic extract of the seeds. When two grains and a third of this extract, obtained from one hundred grains of powdered seeds, were introduced into the cellular tissue of a rabbit in the same way as before, at the end of two minutes, without any previous indication, the animal suddenly became weak, fell on its side, struggled a little with its feet, and ceased to breathe in one minute more. On the chest being immediately laid open, the same phenomena were observed as in the last experiment.

It is evident that this poison is one of great intensity of action upon the lower animals; but I have not endeavoured to ascertain exactly its degree of energy. I may mention, however, that on making trial of the exhausted powder from which the extract used in the preceding experiment was prepared, although no effect could be detected in the course of an hour, in ninety minutes the animal was observed to become suddenly weak, and it died in a few minutes more exactly like the others. This result, which appeared unintelligible at first, was afterwards satisfactorily traced to the residual farina not having been carefully enough washed clear of the second spirituous decoction; so that a little of the poisonous ingredient was inadvertently allowed to remain before the farina was dried. The quantity must have been very small.

The only other fact I have to mention relative to the action of the seed on the lower animals, is one observed incidentally by Mr Macnab. As the seed vegetates, the two fleshy cotyledons or sarcolobes rise partially above ground. In this state one of the seeds growing in the Botanic Garden stove-house was attacked by two slugs, one on each cotyledon. Mr Macnab observing that one

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