CHAPTER XXXIV.

OF POISONS OF THE UMBELLIFEROUS ORDER OF PLANTS. The Natural Order _Umbelliferæ_ contains a variety of plants, to which narcotico-acrid properties have been at different times ascribed. But these properties have been satisfactorily traced in the instance of four species only, the _Conium maculatum_, _Œnanthe crocata_, _Cicuta virosa_, and _Æthusa cynapium_. It is supposed that others may be poisonous. But the facts on the subject are equivocal; for the several species of the family are very apt to be confounded with one another, and there is reason to think that other species have repeatedly been mistaken for one of the four already mentioned. The symptoms caused by the umbelliferous narcotics comprehend chiefly coma, convulsions, paralysis, and delirium. But the knowledge possessed on this head is rather vague, and the phenomena are not unfrequently complex and difficult to observe with accuracy; so that their nature has been sometimes misunderstood. The irritant properties of the poisons of this tribe of narcotico-acrids are seldom well defined. _Of Poisoning with Hemlock._ The first to be mentioned is the common hemlock, or _Conium maculatum_, one of the most abundantly diffused of umbelliferous vegetables. It is distinguished from all those which it resembles by its tall, smooth, spotted stem,—its smooth leaves,—the rugged edge of the five ribs of its fruit,—its singular mousy odour,—and the very peculiar odour of conia, emitted when the pulp or juice of the leaves is mixed with caustic potash. The only other umbelliferous native which has a spotted stem, the _Myrrhis temulenta_, is easily distinguished from hemlock by the whole plant being very hairy. Cases of poisoning with hemlock are not infrequent on the continent, the root having been mistaken for fennel, asparagus, parsley, but particularly parsnep.[2217] It is generally believed to have furnished the poison which was used in ancient times, and especially among the Greeks, for despatching criminals; but we have not any precise information on the subject. A peculiar alkaloid was indicated in hemlock not long ago by Brandes, half a grain of which killed a rabbit with symptoms like those of tetanus.[2218] Other chemists were unable to obtain his results. But the subject was afterwards taken up with success by Geiger, who obtained from the plant a volatile, oleaginous alkaloid, which possesses great energy as a poison.[2219] Mr. Morries-Stirling procured from hemlock by destructive distillation an empyreumatic oil similar in properties to those of hyoscyamus, stramonium and tobacco, but producing in animals a state of pure coma.[2220] The effects of hemlock on the animal system have been variously described by different observers. Sometimes they have appeared to be purely soporific like those of opium; at other times they have resembled the effects of belladonna and thorn-apple; and in the lower animals they are quite different, as I have witnessed them, from what they have been described to be in man,—the phenomena being simply those of asphyxia from paralysis of the muscles, without material convulsions and without insensibility. Its irritant action is not well established. Orfila observed that an ounce of the extract of the leaves killed a dog in forty-five minutes when swallowed, ninety grains killed another through a wound in an hour and a half, and twenty-eight grains another through a vein in two minutes. It therefore acts by entering the blood-vessels. The extract is a very uncertain preparation; the reason of which is, that the alkaloid conia is very easily decomposed in its natural state of mixture by heat or age, being converted into an inert resinoid matter,—that the dried leaves of hemlock contain scarcely any of it,—and that even an extract of the fresh leaves contains little, unless prepared with a gentle heat, yet speedily.[2221] The symptoms remarked by Orfila were convulsions and insensibility; and in the dead body the blood of the left cavities of the heart was sometimes found arterial.—The result of my observations is quite at variance with this statement. In various experiments with a strong extract prepared from the green seeds with absolute alcohol, the only effect I could remark were palsy, first of the voluntary muscles, next of the chest, lastly of the diaphragm,—asphyxia in short from paralysis, without insensibility, and with slight occasional twitches only of the limbs, and the heart was always found contracting vigorously for a long time after death. Thirty grains of a soft extract introduced between the skin and muscles of the back killed a rabbit in five minutes, and a five months’ puppy in twenty minutes.[2222] The root is much less energetic than is represented by some authors, and probably varies in this respect at different seasons. I have found that four ounces and a half of juice, the produce of twelve ounces of roots collected in November, had no effect on a dog when secured in its stomach by a ligature on the gullet; and that four ounces obtained from ten ounces of roots in the middle of June, when the plant was coming into flower, merely caused diarrhœa and languor. Orfila had previously observed that three pounds of roots had no effect in the month of April; but that two pounds in the end of May, when the plant was in full vegetation, killed a dog in six hours.[2223] The alcoholic extract of the juice obtained from six ounces of roots on the last day of May, I have found to kill a rabbit in thirty-seven minutes, when introduced in a state of emulsion between the skin and muscles of the back; and the effects were analogous to those obtained with the extract of the leaves. The differences depending on season will probably account for various persons having found the juice of the root harmless. Gmelin quotes an instance where four ounces of the juice were taken without injury. He adds another where three ounces of the juice of the herb were swallowed daily for eight days with as little effect. But, as he judiciously observes, other less active plants have probably been sometimes mistaken for hemlock.[2224] The alkaloid, conia, seems to be the active principle of hemlock, and is a poison of extraordinary virulence. On investigating this subject in 1835,[2225] I found that it is a local irritant, possessing an acrid taste, and capable of exciting redness or vascularity in any membrane to which it is applied; but that these topical effects are readily overwhelmed by its swift and intense narcotic action. This action consists of swiftly spreading palsy of the muscles, which affects first those of voluntary motion, then the respiratory muscles of the chest and abdomen, and lastly the diaphragm, so as to terminate by causing asphyxia. The paralytic state is usually interrupted from time to time by slight convulsive twitches of the limbs and trunk at the beginning. The muscular contractility is impaired or annihilated by the topical action of the poison, but not by its indirect action through absorption. The heart is not appreciably affected; for it contracts vigorously long after all motion, respiration, and other signs of life are extinct; and it contains after death, not florid but dark blood in its left cavities. The blood undergoes no alteration. The external senses are little, if at all impaired, until the breathing is almost arrested; and volition too is retained. But a contrary inference may be drawn by a careless observer, in consequence of the paralytic state taking away the means, by which in animals sensation is expressed and volition exercised. The action of conia, in short, is confined to the spinal cord; and it acts as a sedative, by exhausting the nervous energy. Conia is probably a deadly poison to all orders of animals: at least I found it to be so to the dog, cat, rabbit, mouse, frog, fly, and flea; and Geiger killed the kite, pigeon, sparrow, slow-worm, and earth-worm with it. It acts through every texture where absorption is carried on readily, through the stomach, eye, lungs, cellular tissue, peritonæum, or veins; and its activity is in proportion to the speed with which absorption is carried on in the part. It acts therefore through absorption. Its activity is increased by neutralization with an acid, by which it is rendered much more soluble in water. Few poisons equal it in subtility and swiftness. A single drop, applied to the eye of a rabbit, will kill it in nine minutes; and three drops in the same way will kill a strong cat in a minute and a half. Five drops, introduced into the throat of a little dog, began to act in thirty seconds, and proved fatal in one minute. And when two grains, neutralized with thirty drops of weak hydrochloric acid, were injected into the femoral vein of a young dog, it died before there was time to note the interval, so that only two or three seconds at most had elapsed, before all internal signs of life were extinct. This extraordinary rapidity of action seems incompatible with its operation taking place by conveyance of the poison with the blood to the spinal cord. Mr. Blake, as formerly mentioned (p. 15), denies that its action in this way was ever so swift in his hands, and alleges that he could never observe the interval to be shorter than fifteen seconds. If the reader, however, will consult the original account of my experiment,[2226] which was made along with Dr. Sharpey, he will see that we could scarcely be mistaken as to the interval in that instance. _Symptoms in Man._—M. Haaf, a French army-surgeon, has described a fatal case of poisoning with hemlock, which closely resembled poisoning with opium. The subject of it, a soldier, had partaken along with several comrades of a soup containing hemlock leaves, and appeared to them to drop asleep not long after, while they were conversing. In the course of an hour and a half they became alarmed on being all taken ill with giddiness and headache; and the surgeon of the regiment was sent for. He found the soldier, who had fallen asleep, in a state of insensibility, from which, however, he could be roused for a few moments. His countenance was bloated, the pulse only 30, and the extremities cold. The insensibility became rapidly deeper and deeper, till he died, three hours after taking the soup.[2227] His companions recovered. Dr. Watson has briefly described two cases which were fatal in the same short space of time. The subjects were two Dutch soldiers, who, in common with several of their comrades, took broth made with hemlock leaves and various other herbs. Giddiness, coma, and convulsions were the principal symptoms. The men who recovered were affected exactly as if they had taken opium.[2228] When the dose is not sufficient to prove fatal, there is sometimes paralysis, attended with slight convulsions, as in a case noticed by Orfila.[2229] More commonly there is frantic delirium. Matthiol has related an instance of this last description, occurring in the cases of a vine-dresser and his wife, who mistook the roots for parsneps Both of them became in the course of the night so delirious that they ran about the house, knocking themselves against every object which came in their way.[2230] Kircher, as quoted by Wibmer, tells a parallel story of two monks who became so raving mad after eating the roots, that they plunged into water, imagining that they were turned into geese, and they were affected for three years with incomplete palsy and neuralgic pains.[2231] These and some other cases of the like kind, recorded by the older medical authors, must be received with reserve. Independently of other considerations, there is often no certainty that the poison was really the hemlock of modern botanists, and not some other umbelliferous vegetable. _Morbid Appearances._—In Haaf’s case the vessels of the head were much congested; and the blood must have been very fluid, for on the head being opened a quantity flowed out, which twice filled an ordinary chamber-pot. This state of the blood likewise occurred in a case which I examined here some years ago along with Dr. C. Coindet of Geneva. A hypochondriacal old woman took by advice of a neighbour two ounces of a strong infusion of hemlock leaves with the same quantity of whisky, which she swallowed in the morning fasting. She died in an hour, comatose and slightly convulsed. The vessels within the head were not particularly turgid; but the blood was everywhere remarkably fluid. Dr. Coindet subsequently found that a small portion of the infusion prevents fresh drawn blood from coagulating; but I suspect there must have been some mistake here, for a carefully prepared alcoholic extract of very great power, which was used in my experiments alluded to above, had no such effect on blood fresh drawn from rabbits and dogs. On account of this extreme fluidity of the blood, it often flows from the nose, but the skin is much marked with lividity.[2232] The fluidity of the blood is nothing more than the result of the proximate cause of death,—slowly formed asphyxia. _Of Poisoning with Water-Hemlock._ Another plant of the order Umbelliferæ, the water-hemlock or _Cicuta virosa_, possesses also great energy as a poison; and in its effects it appears to resemble considerably the hydrocyanic acid. The plant is indigenous. It is easily known from other umbelliferous species inhabiting watery places by the peculiar structure of its root-stock, which is not fleshy, but hollow, and composed of a number of large cells with transverse plates. From a numerous set of experiments with the root of the cicuta performed by Wepfer, it appears to cause true tetanic convulsions in frequent paroxysms, and death on the third day.[2233] Simeon ascertained that the alcoholic extract of the root is very poisonous.[2234] Schubarth found that an ounce of the juice of the stems and leaves, collected after the flowers had begun to blow, produced no effect on the dog.[2235] It is probably inert, or at all events feebly poisonous in this climate, although it grows luxuriantly in many localities. I have found that twelve ounces of juice, expressed from sixteen ounces of roots in the beginning of August, merely caused some efforts to vomit, when secured in the stomach of a dog by a ligature on the gullet; that the alcoholic extract of twelve ounces of leaves gathered at the same time had no effect when introduced in the form of emulsion between the skin and muscles of the back of a rabbit; and that the alcoholic extract of two ounces of unripe seeds proved equally inert when imployed in the same way. _Symptoms in Man._—Wepfer has likewise related several instances which occurred in the human subject. Among the rest he has described the cases of eight children who ate the roots instead of parsneps. Of those who were seriously affected, one, a girl six years old, who ultimately recovered, had tetanic fits, followed by deep coma, from which it was impossible to rouse her for twenty-four hours. Two of them died. The first symptoms in these two were swelling in the pit of the stomach, vomiting or efforts to vomit, then total insensibility, with involuntary discharge of urine, and finally severe convulsions, during which the jaws were locked, the eyes rolled, and the head and spine were bent backwards, so that a child might have crept between the body and the bed-clothes. One of them died half an hour after being taken ill, and the other not long after.[2236] Mayer of Creutsburg mentions four cases, which were occasioned by the roots. One of the individuals, a child three years old, was attacked with colic, vomiting, and convulsions, and died in a few hours. The three others, the eldest of whom was six years of age, had coldness, paleness of the features, dilated immoveable pupils, violent colic, general spasms, and insensibility. The action of the heart was intermitting and the breathing oppressed. After the remains of the roots were brought up by emetics, and infusion of gall was administered, they gradually recovered. They had eaten between them no more than a single root weighing about two ounces, as they had in their possession another of that weight, which they said was not so large. This accident happened in the middle of March.[2237] According to Guersent, poisoning with the cicuta commences with dimness of sight, giddiness, acute headache, anxiety, pain in the stomach, dryness in the throat, and vomiting.[2238] Mertzdorff has related the particulars of the inspection of three cases which proved quickly fatal with convulsions and vomiting. Nothing remarkable seems to have been found except great gorging of the cerebral vessels.[2239] _Of Poisoning with Hemlock Dropwort._ The _Œnanthe crocata_ of botanists, the hemlock dropwort, five-finger-root, or dead-tongue of vernacular speech in England, a species of the same family with the last two, and an abundant plant in some localities throughout this country, has usually been held one of the most virulent of European vegetables. It seems well entitled to this character in general; but climate, or some other more obscure cause, renders it inert in some situations. It is said to be liable to be confounded with common hemlock, or _Conium maculatum_,—a mistake which can happen only in very ignorant hands. It has smooth, dark-green leaves, more fleshy, and much less minutely divided, than those of hemlock; it presents a purplish appearance at the joints only of the stem, and no diffused purple spots; its fruit is oblong and black, not round, rough, and light brown; and its root, instead of being single, long, tapering, and little branched, consists of from two to ten tubers, like fingers, which are white, and terminate in a few rootlets. These tubers are formed annually in summer from the flowering stem of the season, and send out flowering stems the subsequent year. During the first autumn, winter, and spring they are firm, white, and amylaceous; but in their second summer they become more pulpy, less amylaceous, and grayer. At all times they emit, when broken across, an oleo-resinous juice, which quickly becomes yellow; this juice abounds most when the plant, which is growing at their expense, is about to flower; and it abounds much more at this period in localities in the south of England, than in Scotland, especially in the neighbourhood of Edinburgh. Brotero and some others have attempted to subdivide the species into two, the _Œnanthe crocata_ proper, and the _Œ. apiifolia_. But the best authorities deny that these can be distinguished; and from what I have now seen in sundry localities, it appears to me that the distinctions pointed out by Brotero, confessedly obscure enough in themselves, are the result of differences in climate, soil, and situation. The only analysis of this plant with which I am acquainted is one executed in 1830 by MM. Cormerais and Pihan-Dufeillay, who found in the root a resinoid matter, which adheres obstinately to the solid portion of it, and which seems to be the active ingredient.[2240] I have subjected the roots to various processes, and among the rest to that by which Geiger detected conia in hemlock, but without discovering any indication of the existence of an alkaloid. My materials, however, were not well fitted for a chemical analysis; because the œnanthe root of this neighbourhood is inert or nearly so. The whole plant contains a heavy-smelling volatile oil, which may be obtained by distillation in the usual way, and most abundantly from the ripe seeds. This oil is yellowish, viscid, and inert. It is strange that a plant, so universally considered a potent poison, and so frequently the cause of fatal accidents, has not yet been made the subject of physiological investigation. A few imperfect experiments by M. Cormerais and his companion, made with the resinoid matter of the roots, show that this substance produces in animals dulness, convulsions of the voluntary muscles, a semi-paralytic state of the hind legs, and sometimes shortness of breath, vomiting, and fluid evacuations by stool. All the animals experimented on recovered. On repeating these experiments with larger quantities I found the resin of the root, grown near Woolwich, and kindly sent to me by Dr. Pereira, to be a poison of great energy and singular properties. Twenty-four grains obtained from eight ounces of roots in the middle of December, when introduced in the form of emulsion between the skin and muscles of the rabbit, caused in half an hour depression, uneasiness, and hurried breathing,—then twitches of the ears, neck, and fore-legs,—next combined spasm and convulsive starting of the head and limbs,—then, after a quiet interval, a more violent fit of the same kind, affecting the whole body with a singular combination of tetanus and convulsive starting,—finally, after several such fits, a paroxysm more violent than before, ending in immoveable tetanic rigidity, which speedily proved fatal, 78 minutes after the application of the poison. No morbid appearance could be detected in the body. The heart contracted vigorously for some time after death. These phenomena correspond in the main with what has been recorded of the symptoms caused by the roots in man.—Dr. Pereira informs me he had found the juice both of the root and leaves to act as a poison, either when introduced into the peritonæum, or when injected into the veins; and in the latter way it was so energetic as to prove fatal in one minute. _Symptoms in Man._—Since Lobel first took notice of the poisonous properties of the œnanthe root in 1570, an uninterrupted series of observations has been published, down to the present day, showing that in France, Germany, Holland, Spain, and various parts of England as far north as Liverpool, it is at all seasons of the year, even in October and in the beginning of January, a poison of great activity. In several of the cases death has been occasioned by a single handful of the roots, in one instance by a piece no bigger than the finger, or even in consequence of the individuals merely tasting them. A girl seems to have had a narrow escape after eating, with an interval of three hours, two pieces of the size of a walnut. Very seldom has death been delayed beyond four hours, and on some occasions a single hour has been sufficient. Sometimes the symptoms have been slow in making their appearance, an hour and a half having occasionally elapsed before the effects were evident; but in every instance their progress was rapid, once the symptoms had fairly set in; and some died in convulsions almost immediately after being taken ill. The particular effects have been variable. Most generally the first symptoms have been giddiness and staggering, as if from ordinary intoxication, occasionally headache, and often extreme feebleness of the limbs. Stupor has then generally succeeded, sometimes with the intervention of efforts to vomit, sometimes too with an interval of delirium. Convulsions have also commonly made their appearance in the next place; and ere long a state of insensibility has ensued attended in every instance with occasional violent convulsive fits like epilepsy, and with permanent locked-jaw; which symptoms have continued till near death. In one or two cases the individual has suddenly, without any premonitory symptoms, fallen down convulsed, and died almost immediately. In one or two instances again, the effects have rather been those of irritant poisoning, namely, inflammation of the mouth and throat, spasms of the muscles of the throat, vomiting, and excessive weakness and faintness, without any convulsions or insensibility.—It appears then that this plant is a true narcotico-acrid poison. The emanations from the plant are said on some occasions to have proved injurious; but the effect here was probably the work of the imagination. Aware of these singular properties being generally ascribed to the _Œnanthe crocata_, I was anxious to make a methodical examination of the subject, physiologically as well as chemically,—especially as the plant grows in great abundance and very luxuriantly in a locality not far from Edinburgh. But I have found it in that situation, to all appearance, quite inert. The juice of fourteen ounces of the root in the end of October had no effect on a little dog when secured in the stomach by a ligature on the gullet. The juice of sixteen ounces in the middle of June was also without effect. An alcoholic extract of four ounces of the full grown leaves in the end of June, introduced into the cellular tissue in the form of emulsion, had no effect on a rabbit. An alcoholic extract of three ounces of the ripe seeds was administered in the same way with the same result. Finally, the resinoid extract of eight ounces of the root, analogous to that which had proved so deadly in my hands when obtained from Woolwich plants, had also no effect whatever, when prepared from those growing in the neighbourhood of Edinburgh. Relying upon these results, I ate a whole tuber weighing an ounce, without observing any effect, except its disagreeable taste; which was the only circumstance that prevented me from trying a larger quantity.—It may be well to add, that, amidst the numerous cases of poisoning with œnanthe now on record, there is not one that has occurred in Scotland. At the same time, the common people in Scotland are not at all given to rash experiments in cookery, or to make use of vegetables not produced by the care of the gardener or farmer.[2241] The only other locality from which I have been hitherto able to obtain plants for examination is the neighbourhood of Liverpool, where a fatal case of poisoning with it occurred near the close of last century. When the juice of sixteen ounces of this root in the beginning of September was secured in the stomach of a dog, efforts to vomit were produced, followed by several fits of violent convulsions and spasm of the voluntary muscles, a paralytic state of the fore-legs, and a constant tendency to fall backwards; but the animal recovered. No morbid appearances of any note have been observed after death in any of the fatal cases which are recorded.—The most appropriate treatment consists in the prompt employment of emetics, and diffusible stimulants. _Of Poisoning with Fool’s Parsley._ Another umbelliferous plant of great activity is fool’s parsley, or _Æthusa cynapium_. It has occasioned several accidents by reason of its resemblance to parsley,—from which, however, it is at once distinguished by the leaves being dark and glistening on their lower surface, and by the nauseous smell they emit when rubbed. It contains an alkaloid, which crystallizes in rhombic prisms, and is soluble in water and alcohol, but not in ether. It was discovered by Professor Ficinus of Dresden.[2242] Orfila found that six ounces of the juice, when retained in the stomach of a dog, by a ligature, caused convulsions and stupor, and death in an hour.[2243] _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]