XXIX. OF POISONING WITH HYDROCYANIC ACID…

XXIX. OF POISONING WITH HYDROCYANIC ACID

The poisons, whose energy depends on the presence of the prussic or hydrocyanic acid, are of great interest to the physiologist as well as the medical jurist. Some of them are natural productions, derived from the leaves, bark, fruit-kernels, and roots of certain plants; others are formed artificially by complex chemical processes. The species to be here noticed are the hydrocyanic acid itself, and the essential oils and distilled waters of the bitter almond, cherry-laurel, peach-blossom, cluster-cherry, mountain-ash, and bitter cassava. These poisons have for some time attracted great attention on account of their extraordinary power. And indeed in rapidity of action, or the minuteness of the quantity in which they operate, no poison surpasses and very few equal them. They are exceedingly interesting to the medical jurist, because, as they are now generally known, their effects often become the subject of medico-legal investigation: they have been repeatedly taken by accident; they have often been resorted to for committing suicide; and they have likewise been employed as the instruments of murder. A remarkable instance occurred in England towards the close of last century, where murder was committed with the cherry-laurel water; and two cases have been tried in England where death arose from hydrocyanic acid, and the prisoners were charged with administering it, but were found not guilty. These cases will be noticed presently.

Of the Hydrocyanic Acid. SECTION I.—Of its Chemical History and Tests.

This singular substance was discovered some time ago by Scheele; but Gay-Lussac was the first who obtained it in a state of purity. It is familiarly known to chemists under two forms,—as a pure acid, and diluted with water.

The pure acid is liquid, limpid, and colourless. It has an acrid, pungent taste, and a very peculiar odour, which, when diffused through the air, has a very distant resemblance to that of bitter almonds, but is accompanied with a peculiar impression of acridity on the nostrils and back of the throat. It is an error, however, to suppose, as is very generally done, that the odour is the same with that of the almond. It boils at 80°; freezes at 5°; and is very inflammable. I have kept it unchanged for a fortnight in ice-cold water; but at ordinary temperatures it decomposes spontaneously, and becomes brown, sometimes in an hour, and commonly within twelve hours. On this account it is extremely improbable that a case will ever happen, in which the medical jurist will have to examine it in its concentrated form.

When united with water it forms the acid discovered by Scheele, and now kept in the druggist’s shop. In this state it has the same appearance, taste, and smell as the pure acid; but it is less volatile, does not burn, and may be preserved long without change, if excluded from the light. In consequence of its volatility, however, it becomes weak, unless kept with great care; many samples of it also undergo decomposition, and deposit brown flakes, if not excluded from the light; and hence the acid of the shops is very variable in point of strength. The acid prepared by decomposing the solution of the ferro-cyanate of potass by sulphuric acid may be kept for years, even exposed to diffuse light, without being decomposed at all. A French physician made some experiments not long ago on the uncertainty of the strength of the medicinal acid; and he found that he could swallow a whole ounce of one sample, and a drachm of a stronger sample, without sustaining any injury; but on trying some which had been recently prepared by Vauquelin, he was immediately taken ill, as will be related presently, and narrowly escaped with his life.[1840]—The acid of commerce differs much in strength, according to the process by which it has been prepared, and independently of decomposition by keeping. The medicinal acid long used in this country is intended to be an imitation of that of Vauquelin, which contains 3·3 per cent.;[1841] but the London College of Physicians, in adopting it in their last Pharmacopœia, improperly altered the strength to 2 per cent. That of Giese, which keeps well, is of the same strength as the first; that of Schrader contains only one per cent.; that of Göbel 2·5 per cent.; that of Ittner 10 per cent.;[1842] that of Robiquet 50 per cent.[1843] Of the alcoholic solutions the best known are that of Schrader, which contains about 1·5 per cent. of pure acid,—that of the Bavarian Pharmacopœia, which contains 4 per cent.,—that of Duflos, 9 per cent.,—that of Pfaff, 10 per cent.,—and that of Keller, 25 per cent.[1842] These statements are necessary for understanding the cases of poisoning published in foreign works.

The tests for hydrocyanic acid has been examined by M. Lassaigne of Paris, by Dr. Turner of London, and by Professor Orfila. They are its odour, the salts of copper, the salts of iron, and nitrate of silver.

The peculiar odour of the acid is a very characteristic and delicate test of its presence. According to Orfila, the smell is perceptible when no chemical reagent is delicate enough to detect it.[1844] But I doubt the accuracy of this statement, and may farther observe, that I have known some persons nearly insensible of any smell, even in a specimen which was tolerably strong. Hence, when the odour is resorted to as a test, it ought to be tried by several persons.

Sulphate of copper forms with hydrocyanic acid, when rendered alkaline with a little potass, a greenish precipitate, which becomes nearly white, on the addition of a little hydrochloric acid. The purpose of the hydrochloric acid is to redissolve some oxide of copper thrown down by the potass. The precipitate is then the cyanide of copper. This test, according to Lassaigne, will act on the poison when dissolved in 20,000 parts of water. But as the precipitate is not coloured, the test is an insignificant one compared with the next.

If the acid be rendered alkaline by potass, the salts of the mixed peroxide and protoxide of iron produce a grayish-green precipitate, which, on the addition of a little sulphuric acid, becomes of a deep prussian blue colour. Common green vitriol answers very well for this purpose. The salts of the peroxide of iron will also often answer, because, unless carefully prepared, they are never altogether free of protoxide. But the salts of the pure peroxide of iron have no such effect. They cause with the potass a brownish precipitate, which is redissolved on the addition of sulphuric acid, leaving the solution limpid. Mr. Ilott of Bromley has pointed out to me, that the iron test does not act on a weak solution of hydrocyanic acid, if there be an excess of ammonia present, either such from the first, or disengaged by potash from muriate of ammonia; that the blue precipitate is produced by driving off the ammonia with heat; but not by neutralizing it with an acid.

The nitrate of silver is a delicate and characteristic reagent for hydrocyanic acid. A white precipitate, the cyanide of silver, is produced in a very diluted solution; and this precipitate is distinguished from the other white salts of silver, by being insoluble in nitric acid at ordinary temperatures, but soluble in that acid at its boiling temperature. In this action it is necessary to observe that something more is accomplished than simple solution; the cyanide is decomposed, nitrate of silver is formed, and hydrocyanic acid is disengaged by the ebullition. A more characteristic property is, that the precipitate when dried and heated emits cyanogen gas; which is easily known by the beautiful rose-red colour of its flame.[1845]

Sometimes it is necessary to determine the strength of diluted hydrocyanic acid; because, on account of its tendency to decomposition, doubts may be entertained whether a mixture which contains it is strong enough to be dangerously poisonous. According to Orfila, the best method of ascertaining the strength either of a pure solution or of a mixture in syrup, is to throw down the acid with the nitrate of silver and dry the precipitate; a hundred parts of which correspond to 20·33 of pure hydrocyanic acid.

Process for Mixed Fluids.—Some important observations have been made by MM. Leuret and Lassaigne on the effect of mixing animal matters with hydrocyanic acid. The most material of their results are, that if the body of an animal poisoned with the acid is left unburied for three days, the poison can no longer be detected; and that if it is buried within twenty-four hours the poison may be found after a longer interval, but never after eight days. The reason is either that the acid volatilizes, or that it is decomposed. The possibility thus indicated of detecting the poison in the body some days after death has been since confirmed by actual examination in a medico-legal case. In a case of poisoning with hydrocyanic acid, followed by dismemberment of the body for the purpose of concealment, distinct proof of the presence of the poison seven days after death was obtained by the second of the succeeding processes, although the trunk of the body had never been buried, but had been for some time lying in a drain.[1846]

For detecting the poison in mixed fluids Orfila has lately advised the following process. The fluid may be treated with animal charcoal without heat. The colour being thus generally destroyed, the test will sometimes act as usual. Or, without this preparation, a slip of bibulous paper moistened with pure potass, may be immersed in the suspected fluid for a few minutes, and then touched with a solution of sulphate of iron: upon which the usual blue colour will be produced on the paper. If neither of these methods should answer, the fluid is to be distilled.[1847]

Distillation of the fluid is on the whole the best mode of procedure. It was proposed some time before by Lassaigne and Leuret for detecting the poison in the stomach after death. The steps of their process, which appears to me the best yet proposed, are as follows. The contents after filtration are to be neutralized with sulphuric acid if they are alkaline, in order to fix the ammonia which may have been disengaged by putrefaction; the product is then to be distilled from a vapour-bath till an eighth part has passed over into the receiver; and the distilled fluid is to be tested with the sulphate of iron in the usual way.[1848] Orfila maintains that from hydrocyanized syrup only two-thirds of the acid can be distilled over; and cautions the analyst against estimating quantity by such means.[1849] M. Ossian Henry has proposed to condense the acid in distillation by a much more complex process, which consists in obtaining it in the first instance in the form of cyanide of silver.[1850] But with a good refrigeratory there is no difficulty in condensing every particle of acid with no other aid than cold water.

By this process Lassaigne could detect the poison in a cat or dog killed by twelve drops and examined twenty-four or forty-eight hours after death.[1851] But Dr. Schubarth has objected to it,—and the same objection will apply to every process in which heat is used,—that hydrocyanic acid may be formed during distillation by the decomposition of animal matter.[1852] His objection, however, appears only to rest on conjecture or presumption at farthest; and I doubt whether, supposing the distillation to go on slowly in the vapour-bath, the heat is sufficient to bring about the requisite decomposition. The force of the objection must be decided by future researches.

It is worthy of remark that hydrocyanic acid is apt to be formed in the course of the changes produced by various agents in organic matters. These are probably more numerous than the toxicologist is at present exactly aware of. An instance of its formation in the course of the decay of unsound cheese has been ascertained lately by Dr. Witling;[1853] and another example will be mentioned under the head of spurred rye.

Cyanide of Potassium.—The only compound of hydrocyanic acid which requires notice is the cyanide of potassium. This is, when pure, a white salt, bitter, not decomposable by a red heat unless in contact with air, very soluble in water, and sparingly so in rectified spirit. Its watery solution restores the blue of reddened litmus, and does not precipitate lime-water: the mixed sulphates of the two oxides of iron form with it Prussian blue: nitrate of silver causes a white precipitate insoluble in cold nitric acid, but disappearing when the acid is boiled: sulphate of copper causes an apple-green precipitate, which becomes white on the addition of hydrochloric acid: chloride of platinum or perchloric acid will indicate the potash. In a complex organic mixture it is difficult to detect the potash; but hydrocyanic acid may be obtained from it by distilling the suspected fluid with tartaric acid.[1854]

SECTION II.—Of the Action of Hydrocyanic Acid and the Symptoms it excites in Man.

The effects of hydrocyanic acid on the animal system have been examined by several physiologists. The best experiments with the concentrated acid are those of M. Magendie; who says that, if a single drop be put into the throat of a dog, the animal makes two or three deep hurried respirations, and instantly drops down dead; that it causes death almost as instantaneously when dropped under the eyelid; and that when it is injected into the jugular vein, the animal drops down dead at the very instant, as if struck with a cannon ball or with lightning.[1855]

On repeating these experiments in order to determine less figuratively the shortest period which elapses before the poison begins to operate, as well as the shortest time in which it proves fatal,—two points it will presently be found important to know,—I remarked that a single drop, weighing scarcely a third of a grain, dropped into the mouth of a rabbit, killed it in eighty-three seconds, and began to act in sixty-three seconds,—that three drops weighing four-fifths of a grain, in like manner killed a strong cat in thirty seconds, and began to act in ten,—that another was affected by the same dose in five and died in forty seconds,—that four drops weighing a grain and a fifth did not affect a rabbit for twenty seconds, but killed it in ten seconds more,—and that twenty-five grains, corresponding with an ounce and a half of medicinal acid, began to act on a rabbit as soon as it was poured into its mouth, and killed it outright in ten seconds at farthest. Three drops injected into the eye acted on a cat in twenty seconds, and killed it in twenty more; and the same quantity dropped on a fresh wound in the loins acted in forty-five and proved fatal in 105 seconds. Dr. A. T. Thomson says he has seen the concentrated acid kill a strong dog in two seconds.[1856] Mr. Blake on the other hand alleges that all the accounts which represent the action of the poison to begin in less than ten seconds are exaggerated, because he could never find it to act more quickly, even when thirty minims of concentrated acid were injected at once into the femoral vein.[1857] But it is impossible that any negative results can outweigh positive observations, especially when made, as mine were, expressly with the view of ascertaining the shortest interval. In the slower cases enumerated above there were regular fits of violent tetanus; but in the very rapid cases the animals perished just as the fit was ushered in with retraction of the head. In rabbits opisthotonos, in cats emprosthotonos, was the chief tetanic symptom.—The practical application of these experiments will appear presently.

Of all the forms in which the pure acid can be administered, that of vapour appears the most instantaneous in operation. M. Robert found, that when a bird, a rabbit, a cat, and two dogs were made to breathe air saturated with its vapour, the first died in one second, the second also in a single second, the cat in two, one dog in five, and the other dog in ten seconds.[1858]

The effects of the diluted acid are the same when the dose is large, but somewhat different when inferior doses are given. These effects have been observed by many physiologists; but the most accurate and extensive experiments are those of Emmert published in 1805,[1859] those of Coullon in 1819,[1860] and those of Krimer in 1827.[1861] They found that when an animal is poisoned with a dose not quite sufficient to cause death, it is seized in one or two minutes with giddiness, weakness and salivation, then with tetanic convulsions, and at last with gradually increasing insensibility; that after lying in this state for some time, the insensibility goes off rapidly and is succeeded by a few attacks of convulsions and transient giddiness; and that the whole duration of such cases of poisoning sometimes does not exceed half an hour, but may extend to a whole day or more.—When the dose is somewhat larger the animal perishes either in tetanic convulsions or comatose; and death for the most part takes place between the second and fifteenth minute. I have seen the diluted acid, however, prove fatal with a rapidity scarcely surpassed by the pure poison. Thus in an experiment with Vauquelin’s acid, made on a strong cat at the same time with the second and third of the experiments with the pure acid detailed above, I found that thirty-two grains, which contain one of real acid, began to act in fifteen seconds, and proved fatal in twenty-five more. According to Schubarth’s experiments death may be sometimes delayed for thirty-two minutes;[1862] but if the animal survives that interval, it recovers. He farther states, that during the course of the symptoms the breath exhales an odour of hydrocyanic acid.[1863] Coullon once saw a dog die after nineteen hours of suffering; but cases of this duration are exceedingly rare.[1864] When the dose is very large Mr. Macaulay, as will afterwards be mentioned (p. 590), has found death take place in a few seconds, exactly as when the pure acid is given.

The body presents few morbid appearances of note. The brain is generally natural. Yet occasionally its vessels are turgid; and Schubarth once found even an extravasation of blood between its external membranes in the horse.[1865] The heart and great vessels are distended with black blood, which is commonly fluid, but occasionally coagulated as usual. The lungs, according to Schubarth, are sometimes pale, but much more generally injected and gorged with blood.[1866] The pure acid, according to Magendie, exhausts the irritability of the heart and voluntary muscles so completely, that they are insensible even to the stimulus of galvanism.[1867] The diluted acid has not always this effect. In the experiments of Coullon the heart and intestines contracted, and the voluntary muscles continued contractile, after death as usual.[1868] So too Mr. Blake remarked both by inspection of the body after death, and by means of the hæmadynamometer during life, that, when the poison is introduced directly into a vein, so as to prove fatal in forty-five seconds, the contractions of the heart, though irregular, are not materially impaired in energy.[1869] On the other hand Schubarth states that the heart is never contractile, although the intestines and voluntary muscles retain their contractility.[1870] The reason of these discrepant statements is that, as I have had occasion to observe, a considerable difference really prevails in experiments conducted under circumstances apparently the same. In eight experiments on cats and rabbits with the pure acid the heart contracted spontaneously, as well as under stimuli, for some time after death, except in the instance of the rabbit killed with twenty-five grains, and one of the cats killed by three drops applied to the tongue. In the last two the pulsations of the heart ceased with the short fit of tetanus which preceded death; and in the rabbit, whose chest was laid open instantly after death, the heart was gorged and its irritability utterly extinct. The later researches of Dr. Lonsdale likewise show great varieties in the condition of the heart; and he has been led to conclude that the diluted acid does not perceptibly influence the heart, while the pure acid enfeebles it, if introduced into the stomach, but arrests it, if injected into the windpipe.[1871]

The experiments of Emmert, Coullon, and Krimer show that the diluted acid acts most energetically through the serous membranes, and next upon the stomach; that it also acts with energy on the cellular tissue; that it has no effect when applied to the trunks or cut extremities of nerves, or to a fissure made in the brain or spinal marrow; that its action is prevented when the vessels of any part are tied before the part is touched with the poison; that its action is not prevented by previously dividing the nerves; and that it may sometimes be discovered in the blood after death by chemical analysis,[1872] and frequently by the smell when analysis cannot succeed in separating it.[1873] These results favour the supposition that hydrocyanic acid acts through the medium of the blood-vessels. But the extreme rapidity of its operation in large doses is usually considered incompatible with an action through the blood, or any other channel except direct conveyance along the nerves. The tremendous rapidity of action indicated by the experiments of Magendie, or of Mr. Macaulay (p. 543), of M. Robert, as well as in some of those performed by myself,—certainly appears rather inconsistent with the notion, that the acid must enter the blood-vessels before producing its effects.

This acid acts on the brain and also on the spine independently of its action on the brain. Its action on both is clearly indicated by the combination of coma with tetanus. The independent action on the spine is well shown by the following experiment of Wedemeyer. In a dog the spinal cord was divided at the top of the loins, so that no movement took place when the hind-legs were pricked: hydrocyanic acid being then introduced into a wound in the left hind-leg, symptoms of poisoning commenced in one minute, and the hind-legs were affected with convulsions as well as the fore-legs.[1874]

Hydrocyanic acid affects all animals indiscriminately. From the highest to the lowest in the scale of creation all are killed by it; and all perish nearly in the same manner. Such is the result of a very extensive series of experiments by Coullon.

It is scarcely necessary to observe that hydrocyanic acid acts energetically as a poison, through whatever channel it is introduced into the body. Whether it be swallowed, or injected into the rectum, or dropped into the eye, or applied to a fresh wound, or inhaled in the form of vapour, its action is exerted with tremendous energy. Perhaps it may even act through the sound skin. It has not, hitherto, indeed, been found to affect animals in this way, evidently because their skin is too thick and impermeable. But M. Robiquet informed me that once, while he was making some experiments on the tension of its vapour, his fingers, after being some time exposed to it, became affected with numbness, which lasted several days; I have repeatedly remarked the same effect when handling tubes which contained the concentrated acid; and Emmert found that the essential oil of bitter almond, applied to the uninjured skin of the back of a rabbit, produced the usual symptoms and death: and that the peculiar odour of the poison was quite distinct after death in the deep-seated muscles of the back.[1875]

This substance is poisonous in all its chemical combinations. Coullon remarked that two drops of the hydrocyanate of ammonia killed a sparrow in two minutes.[1876] Robiquet and Magendie found that a hundredth part of a grain of the cyanide of potassium killed a linnet in thirty seconds, and five grains a large pointer in fifteen minutes;[1877] Orfila has related an instance of death in the human subject within an hour after the administration of six grains of cyanide of potassium in an injection;[1878] and in a recent experimental investigation the same author found that this salt produces all the effects of hydrocyanic acid.[1879] Schubarth killed a dog in twenty minutes with twenty drops of the diluted acid neutralized by ammonia,[1880] and another in three hours with twenty-five drops neutralized by potass. These facts are a sufficient answer to a statement made by Mr. Murray of London, to the effect, that a considerable dose of the acid may be given without injury to a rabbit,[1881] if previously rendered alkaline by ammonia. But, nevertheless, as will be seen under the head of the treatment, ammonia, as Mr. Murray stated, is a good antidote when administered after the poison as a stimulant.

The ferro-cyanates, or prussiates, do not possess deleterious properties. These salts were at one time considered compounds of hydrocyanic acid with a double oxidized base, oxide of iron being one. Thus the prussiate of potass was considered a compound of hydrocyanic acid with potass and oxide of iron. But since the investigations of Mr. Porrett, it has been admitted that there is only one base, potash; and that it is in union with a hydracid, called ferro-cyanic acid, the radicle of which is a ternary body composed of carbon, azote, and iron. The physiological effects of this substance, which have been examined by many experimentalists, are favourable to Porrett’s opinion; for although some have found it poisonous, all agree in assigning it very feeble properties, and some have not been able to discover in it any deleterious quality at all. Coullon observes that Gazan killed a dog with two drachms, and Callies another with three drachms of the salt met with in commerce.[1882] Schubarth found that half an ounce had not any material effect on dogs, even when vomiting did not occur for half an hour;[1883] and Callies, who found the salt of commerce somewhat poisonous, also remarked, that when it was carefully prepared, several ounces might be given without harm.[1884] D’Arcet once swallowed half a pound of a solution without any injury.[1885] Similar results were obtained previously with smaller doses by Wollaston, Marcet,[1886] and Emmert,[1887] as well as afterwards by Dr. Macneven,[1888] and Schubarth,[1889] who found that a drachm or even two drachms might be taken with impunity by man and the lower animals.

The sulpho-cyanic acid, another substance analogous in chemical nature to the ferro-cyanic, was once supposed like it to be a poison of great activity, but this is doubtful. Professor Mayer of Bonn ascertained that a drachm and a half of a moderately strong solution of the acid sometimes killed a rabbit in ninety seconds when injected into the windpipe, and that the same quantity of a solution of sulpho-cyanate of potassa might occasion death in the course of four hours; but that some rabbits took half an ounce of the former and three drachms of the latter without material harm, both when administered through the windpipe, when injected into the rectum, and when introduced into the stomach by a gullet-tube. In the fatal cases death took place under symptoms of oppressed breathing, rarely attended with convulsions; and extensive traces of irritation were found in the alimentary canal.[1890] Dr. Westrumb of Hameln, however, seems to have found it more active in the form of sulpho-cyanate of potassa. Two scruples in an ounce of water produced in a dog spasmodic breathing, convulsions, efforts to vomit, and death in seven minutes; and forty grains killed another in less than two hours. In the latter animal he detected the poison by the sulphate of iron in the blood, lungs, liver, spleen and kidneys.[1891] Some experiments by Soemering would even make it out to be a poison of very great energy; for half a drachm of concentrated sulpho-cyanic acid given to a dog occasioned immediate death; and the same quantity of sulpho-cyanate of potassa killed another in one minute.[1892]

Cyanic and cyanous acids are not poisonous, according to the experiments of Hünefield;[1893] but cyanogen is a powerful poison, as will be mentioned under the head of the Narcotic Gases.

The symptoms of hydrocyanic acid observed in man are very similar to those witnessed in animals.

Coullon has given a good account of the effects of small doses as ascertained by experiment on himself. When he took from 20 to 86 drops of a diluted acid, he was attacked for a few minutes with nausea, salivation, hurried pulse, weight and pain in the head, succeeded by a feeling of anxiety, which lasted about six hours.[1894] Such symptoms are apt to be induced by too large medicinal doses. Another remarkable symptom which has been sometimes observed during its medicinal use is salivation with ulceration of the mouth. Dr. Macleod thrice had occasion to remark this in patients who had been using the drug for about a fortnight, and twice in one individual; and Dr. Granville says he had also twice witnessed the same effect.[1895]

As to the effects of fatal doses, it is probable that in man, as in animals, two varieties exist. When the dose is very large, death will in general take place suddenly, without convulsions. But for obvious reasons the symptoms in such cases have not been hitherto witnessed.

The most complete account of the symptoms from fatal doses when convulsions occur, is given in a case reported by Hufeland of a man, who, when apprehended for theft, swallowed an ounce of alcoholized acid, containing about forty grains of the pure acid. He was observed immediately to stagger a few steps, and then to sink down without a groan, apparently lifeless. A physician, who instantly saw him, found the pulse gone and the breathing for some time imperceptible. After a short interval he made so forcible an expiration that the ribs seemed drawn almost to the spine. The legs and arms then became cold, the eyes prominent, glistening, and quite insensible; and after one or two more convulsive expirations he died, five minutes after swallowing the poison.[1896]

In Horn’s Journal is recorded another case which also proved fatal in five minutes, with precisely the same symptoms.[1897] A short notice of what appears to have been a similar case is given in the Annales de Chimie. The person was a chemist’s servant, who swallowed a large quantity of the alcoholic solution by mistake for a liqueur, the poison having been accidentally left on the table by her master, who had been showing it as a curiosity to some friends. No account is given of the symptoms, farther than that she died apoplectic in two minutes.[1898] To these cases may be also added a short notice of the French physician’s case mentioned at the commencement of this chapter. It will convey a good idea of the operation of the poison when not quite sufficient to kill. Very soon after swallowing a tea-spoonful of the diluted acid he felt confusion in the head, and soon fell down insensible, with difficult breathing, a small pulse, a bloated countenance, dilated insensible pupils, and locked jaw. Afterwards he had several fits of tetanus, one of them extremely violent. In two hours and a half he began to recover his intellects and rapidly became sensible; but for some days he suffered much from ulceration of the mouth and violent pulmonary catarrh, which had evidently been excited by the ammonia given for the purpose of rousing him. This gentleman had eructations with the odour of the acid three or four hours after he took it; and during the earlier symptoms the same odour was exhaled by his breath.[1899] The hydrocyanic odour of the breath is of course an important distinguishing character, which would appear, from the observations of Dr. Lonsdale on animals,[1900] to occur more frequently than might be supposed from the silence observed on the subject by the reporters of cases.

Hydrocyanic acid is not considered a cumulative poison,—that is, the continued use of frequent small doses is not believed to possess the power recognised in iodine, mercury, and foxglove, of gradually and silently accumulating in the body, and then suddenly breaking out with dangerous or fatal violence. The frequent experience of practitioners in this and other countries seems to prove that hydrocyanic acid possesses no such property. It is right at the same time to mention, that a case published by Dr. Baumgärtner of Freyburg has been thought by some[1901] to establish the reverse. A man had taken for two months, on account of chronic catarrh, ten drops of Ittner’s acid daily in doses of one grain, without experiencing the slightest toxicological effect. At length he was found one morning in bed apparently labouring under the poisonous operation of the acid. He had headache, blindness, dilated insensible pupil, feeble irregular pulse, occasional suspension of the breathing, and rapidly increasing insensibility. The cold affusion and ammonia were immediately resorted to, and at first with advantage. But in no long time spasms commenced in the toes, and gradually affected the rest of the body, till at length violent fits of general tetanus were formed, lasting for six or ten minutes, and alternating in the intervals with coma. Venesection was next resorted to; after which the spasms were confined to the jaw and eyes. Delirium succeeded, but was removed by a repetition of the blood-letting. At four in the afternoon he was tolerably sensible; during the night delirium returned; at ten next morning he recovered his sight; and on the subsequent morning he had no complaint but headache and pain in the eyes.[1902] This case differs so much from every other in the collateral circumstances, as well as in duration, that, although the symptoms themselves correspond with those of poisoning with hydrocyanic acid, we may justly suspect either some other cause, or the accidental administration of too large a dose. It ought, however, to turn the attention of practitioners to the possibility of this poison acting by the accumulation of the effects of small doses frequently repeated for a great length of time.

The period within which hydrocyanic acid usually proves fatal is fixed with considerable accuracy, not only by the cases observed in the human subject, but likewise by the experiments of many physiologists, and more especially those of Schubarth (p. 583). It is probable that very large doses occasion death in a few seconds; and at all events a few minutes will suffice to extinguish life when the dose is considerable; but if the individual survive forty minutes, he will generally recover. In the course of a dreadful accident which happened a few years ago in one of the Parisian hospitals, when seven epileptic patients were killed at one time by too large doses of the medicinal acid, it was found that several did not die for forty-five minutes.[1903] But the researches of Schubarth would certainly justify the expectation that recovery will take place under active treatment when the patient survives so long.—These facts may be highly important in the practice of medical jurisprudence.

The period within which it begins to operate ought also to be accurately ascertained for the same reason. Indeed in a very interesting trial, which took place a few years ago in this country, the fate of the prisoner depended in a great measure on the question, within how short a time the effects of this poison must show themselves?[1904] The nature of the case was as follows: An apothecary’s maid-servant at Leicester who was pregnant by her master’s apprentice, was found one morning dead in bed; and she had obviously been poisoned with hydrocyanic acid. Circumstances led to the suspicion that the apprentice was accessary to the administration of the poison. On the other hand, it was distinctly proved that the deceased had made arrangements for a miscarriage by artificial means on the night of her death; and it was therefore represented, on the part of the prisoner, that she had taken the poison of her own accord. But the body was found stretched out in bed in a composed posture, with the arms crossed over the trunk, and the bed-clothes pulled smoothly up to the chin; and at her right side lay a small narrow-necked phial, from which about five drachms of the medicinal prussic acid had been taken, and which was corked and wrapped in paper. There naturally arose a question, whether the deceased, after drinking the poison out of such a vessel, could, before becoming insensible, have time to cork up the phial, wrap it up, and adjust the bed-clothes?[1905] To settle this point, experiments were made at the request of the judge, by Mr. Macaulay, Mr. Paget, and several other medical men of Leicester; and on the trial they, with the exception of Mr. Paget, gave it as their opinion, founded on the experiments, that the supposed acts of volition, although within the bounds of possibility, were in the highest degree improbable. The chief experiments were three in number, from which it appeared that one dog was killed with four drachms in eight seconds, another with four drachms in seven seconds, and another with four drachms and a half in three seconds; but in other experiments the interval was greater.—For these particulars I am indebted to Mr. Macaulay.

In the first edition of this work I expressed my concurrence with the majority of the witnesses. But some facts, which came subsequently under my notice, led me to think that this concurrence was given rather too unreservedly. I still adhere so far to my original views as to think it improbable that, if the deceased, after swallowing the poison, had time to cork the phial, wrap it in paper, pull up the bed-clothes, and place the bottle at her side, the progress of the symptoms could have been so rapid and the convulsions so slight, as to occasion no disorder in the appearance of the body and the bed-clothes,—and I still likewise think, that after swallowing so large a dose it was improbable she could have performed all the successive acts of volition mentioned above—with ordinary deliberation. But I am informed on good authority, that some gentlemen interested in the case found by actual trial, that all the acts alluded to might be accomplished, if gone about with promptitude, within the short period, which, in some of their experiments, the witnesses found to elapse, before the action of the poison commenced. And such being the fact, we ought not perhaps to attach too great importance to the other argument I have employed,—the probability of disorder in the body and bed-clothes from the convulsions; for if the poisoning commenced very soon, the convulsions might have been slight. The results of my own experiments related in p. 582, although on the whole confirmatory of those of Mr. Macaulay and his colleagues, are nevertheless sufficient to prove that large doses occasionally do not begin to operate with such rapidity as was observed in their experiments; for in one instance four drops of concentrated acid, equivalent to two scruples of medicinal acid, did not begin to act on a rabbit for twenty seconds; and certainly, for so small an animal, two scruples are as large a dose as five drachms for a grown-up girl.

The two following cases will throw some farther light on the time within which this poison begins to act on man when taken in large quantity. The first case shows, that even when an enormous dose is taken, a few simple voluntary acts may be executed before the symptoms begin. In this instance which is related by Dr. Gierl of Lindau, the dose was no less than four ounces of the acid of the Bavarian Pharmacopœia, which contains four per cent. of pure acid, and is equivalent to five ounces at least of that commonly used in Britain and France. The subject, an apothecary’s assistant, was found dead in bed, with an empty two-ounce phial on each side of the bed,—the mattrass, which is used in Germany instead of blankets, pulled up as high as the breast,—the right arm extended straight down beneath the mattrass,—and the left arm bent on the elbow.[1906] The second case proves that, although one or two acts of volition may be accomplished, the interval is so very brief that these acts can only be of the simplest kind. An apothecary’s apprentice-lad was sent from the shop to the cellar for some carbonate of potass; but he had not been a few minutes away, when his companions heard him cry in a voice of great alarm, “Hartshorn! Hartshorn!” On instantly rushing down stairs, they found him reclining on the lower steps and grasping the rail; and he had scarcely time to mutter “Prussic acid!” when he expired,—not more than five minutes after leaving the shop. On the floor of the cellar an ounce-phial was found, which had been filled with the Bavarian hydrocyanic acid, but contained only a drachm. It appeared that he had taken the acid ignorantly for an experiment; and from the state of the articles in the cellar, it was evident that, alarmed at its instantaneous operation, he had tried to get at the ammonia, which he knew was the antidote, but had found the tremendous activity of the poison would not allow him even to undo the coverings of the bottle.[1907]

When the quantity of the poison is small, a much longer interval may elapse before the commencement of its action. Thus, when the dose is barely short of what is required to occasion death, the effects may be postponed even for fifteen minutes, as in a case which occurred to Mr. Garson of Stromness.[1908] This, so far as I am at present aware, is the extreme limit of interval hitherto observed.

In the trial related above the prisoner Freeman was found Not Guilty.

It is important to fix, if possible, the smallest fatal dose of hydrocyanic acid. This will vary with particular circumstances, such as the strength of the individual, and the fulness or emptiness of the stomach at the time. The cases of the Parisian epileptics, who were killed each by a draught containing two-thirds of a grain of pure acid,[1909] will supply pointed information. For, on the one hand, considering the long time they survived, it is not probable that a dose materially less would have a fatal effect on man. And on the other hand repeated instances of recovery have been observed, where the dose was as great or even greater. Thus Dr. Geoghegan had a patient who recovered from a state of extreme danger after taking two-thirds of a grain;[1910] and Mr. Banks of Lowth met with a case of recovery in similar circumstances, where the dose was very nearly a whole grain.[1911]

It is almost unnecessary to add, that in man, as in animals, this poison will act violently, through whatever channel it may be introduced into the body. It has not been positively ascertained to act with force through the unbroken skin. The chemist Scharinger indeed was supposed to have been killed in consequence of accidentally spilling the acid on his naked arm;[1912] but this was in all probability a mistake. Should the skin be freely exposed to the air it seems reasonable to expect that the poison will evaporate before it could act with energy; but if confined by pledgets or otherwise, a different result might ensue. Through every other surface, however, besides the unbroken skin, hydrocyanic acid acts with very great power; and it is in particular important to remember that its power is very great when inhaled, so that dangerous accidents have ensued even from its vapour incautiously snuffed up the nostrils. I have known a strong man suddenly struck down in this way; a French physician, M. Damiron, has related the case of an apothecary who remained insensible for half an hour subsequently to the same accident;[1913] and cases of the kind are more apt to occur than might at first view be thought, because, contrary to what is generally believed and stated in chemical as well as medico-legal works, its smell is for a few seconds barely perceptible, and never of the kind which these accounts would lead one to anticipate. Accidental death may readily arise from its action on a wound or an abraded surface. Sobernheim mentions that Mr. Scharring, a druggist at Vienna, was poisoned in consequence of a phial of the acid breaking in his hand and wounding it; and he expired in an hour.[1914]

The only case with which I am acquainted of poisoning with the artificial compounds of hydrocyanic acid is that formerly alluded to as having been occasioned by the cyanide of potassium. Six grains dissolved in a clyster amounting to six ounces, occasioned general convulsions, palpitations, slow laboured breathing, coldness of the limbs, dilated pupil, fixing of the eyeballs, and death in one hour,—phenomena much the same with those produced by the acid itself.[1915]—Another case has been published, in which a French physician, ignorant of the correct dose, prescribed a potion with three grains of cyanide of potassium twice a day. Immediately after the first dose the patient was seized with the usual symptoms of poisoning with hydrocyanic acid; and expired in three-quarters of an hour.[1916] In noticing the first of these cases, Orfila draws the attention of practitioners particularly to the fact, that not long before a similar dose of a sample of cyanide, which had been moist for some time, was twice administered with impunity. The reason is that the cyanide of potassium undergoes decomposition when acted on by water, or when long kept.

SECTION III.—Of the Morbid Appearances produced by Hydrocyanic Acid.

Under this head the appearances in a special case will first be mentioned, and then the varieties to which they are liable.

In Hufeland’s case [p. 587] the inspection was made the day after death. The eyes were still glistening, like those of a person alive; but the countenance was pale and composed like one asleep. The spine and neck were stiff, the belly drawn in, the back alone livid. The body generally, the blood even within the head, and especially the serous cavities, exhaled a hydrocyanic odour, so strong as to irritate the nostrils. The blood was every where very fluid, so that two pounds flowed from the incision in the scalp and twelve ounces from that of the dura mater; and it had a glimmering bluish appearance, as if Prussian blue had been mixed with it. The vessels of the brain were gorged, the substance of the brain natural, and the left ventricle distended with half an ounce of serum. The villous coat of the stomach was red, easily removed with the nail, and gangrenous.[1917] The intestines were reddish, and the liver gorged. The lungs were also turgid, and to such a degree in the depending parts as to resemble the liver. The arteries and left cavities of the heart were empty, the veins and right cavities distended.

In commenting on this description it is first to be remarked, that the blood, as in the preceding case, is generally altered in nature. Ittner, who made some good experiments on the subject, found it in animals black, viscid, and oily in consistence.[1918] Emmert found it fluid and of a cochineal colour. In a case related by Mertzdorff of an apothecary’s apprentice, who was found dead in bed after swallowing three drachms and a half of diluted acid,[1919] in the case recorded in Horn’s Archiv, and in that related by Dr. Gierl, it was fluid. It was also perfectly fluid every where in the bodies of the seven epileptic patients poisoned at Paris. Yet this state is not invariable. Coullon, though his results tally in general with those of Ittner and Emmert, has given some experiments in which the blood coagulated after flowing from the body;[1920] and in the case of an apothecary related in Rust’s Journal it was found coagulated in the heart.[1921]

In the next place, Magendie and other physiologists have observed that, as in Hufeland’s case, the blood and cavities of the body in animals exhale a hydrocyanic odour, even though the quantity taken was small. The blood did so likewise in the heart of the apothecary just mentioned as well as throughout the whole body in the case described in Horn’s Journal. The odour, however, is not always present. For example, there was none in the case of another German apothecary, who poisoned himself with an ounce, as recorded in a later volume of Rust’s Journal;[1922] neither was there any odour in the blood in Mertzdorff’s case, although it was strong in the stomach; nor in the blood nor any other part of the body in the Parisian epileptics. It also appears from an experiment by Schubarth,[1923] and from a case by Leuret where life was prolonged above fifteen minutes,[1924]—that the odour may be distinct in the blood, brain, or chest, when hardly any is to be perceived in the stomach. Schubarth has inquired with some care into the circumstances under which the hydrocyanic odour may, or may not, be expected. He states, as the result of his researches, that if the dose is sufficient to cause death within ten minutes, the peculiar odour will always be remarked in the blood of the heart, lungs, and great vessels, provided the body have not been exposed to rain or to a current of air, and the examination be made within a moderate interval,—for example, twenty-one hours for so small an animal as a dog; but that, if the dose is so small that life is prolonged for fifteen, twenty-seven, or thirty-two minutes, then even immediately after death it may be impossible to remark any of the peculiar odour, evidently because, as already mentioned, the acid is rapidly discharged by the lungs; and that even when the dose is large enough to cause death in four minutes, the smell may not be perceived if the carcase has been left in a spacious apartment for two days, or exposed to a shower for a few hours only. These facts explain satisfactorily why no odour could be perceived in the bodies of the Parisian epileptics; for they lived from half an hour to forty-five minutes. The poison may exist in the stomach, though not appreciable by the sense of smell. In Chevallier’s case mentioned above, the contents of the stomach had not any odour of hydrocyanic acid; which, however, was evident to the sense of smell, and plainly indicated by various tests, in the fluid obtained by distilling the contents.

The presence of this odour in the blood may be accounted strong evidence of poisoning with hydrocyanic acid, if it is unequivocal to the sense of several individuals. An exhalation of the same kind is occasionally formed by natural processes in the excrement. Itard once remarked in a case of inflammation of the intestines, and again in a case of inflamed liver, a strong smell of bitter almonds in the fæces, although no medicine containing hydrocyanic acid had been given.[1925] Mr. Taylor mentions that he once observed a sort of hydrocyanic odour in the brain of a person who died of natural disease.[1926] These facts will render the inspector cautious, but can scarcely throw a doubt over evidence derived from an unequivocal hydrocyanic odour in the blood.

Few successful attempts have yet been made to detect the acid in the blood by chemical analysis. The odour may be present, although chemical analysis fails in eliciting any indication. This follows from the observations of Dr. Lonsdale,[1927] as well as of various authors quoted by him in his paper. The cyanide of potassium has been detected by Mayer not merely in the blood, but likewise in the serous secretions and sundry soft solids.[1928]

In most instances,—for example, in the Parisian epileptics, the state of the brain, as to turgescence of vessels, has corresponded with the description given by Hufeland. Venous turgescence and emptiness of the arterial system are commonly remarked throughout the whole body. Thus in the epileptic patients, the heart and great arteries were empty; the great veins gorged; the spleen gorged, soft, and pultaceous; the veins of the liver gorged; and the kidneys of a deep violet colour, much softened, and their veins gorged with black blood.

It is impossible that hydrocyanic acid could cause gangrene of the stomach, which is said to have been witnessed in Hufeland’s case. But there are often signs of irritation in that organ. The villous coat has been found red in animals; it was shrivelled, and its vessels were turgid with black blood in the instance of the apothecary mentioned in the fourteenth volume of Rust’s Journal; in Mertzdorff’s case it was red and checkered with bloody streaks; and in the case related by Dr. Gierl, where four ounces were swallowed, it was dark-red, as it were tanned or steeped in spirits, and easily separated from the subjacent contents. The contents of the stomach have in every instance had a strong hydrocyanic odour, except in the cases of the Parisian epileptics, and in those related by Leuret and by Chevallier. According to the experiments of Lassaigne and Schubarth, formerly noticed, it is not to be looked for when the body has been kept a few days, more especially if the individual lived some time. Dr. Lonsdale generally found it eight or nine days after death in animals, which had been either buried during that time, or kept in an apartment at the temperature of 50° F.[1929] In a case which occurred not long ago in London the poison was found in the stomach five days after death. A coroner’s inquest had terminated in a verdict of natural death. But suspicions having arisen, that the man had poisoned himself in anticipation of a charge of forgery, another inquiry was made; when the odour of hydrocyanic acid was evolved from the contents of the stomach, and the distilled water obtained from them yielded decisive chemical evidence of its being present.[1930] It is important to observe, in reference to the evidence of hydrocyanic acid in the stomach, that here, as in the instance of the blood, the odour may be strong, and yet the poison may not be discoverable by analysis. This fact rests on the united testimony of Coullon, Vauquelin, Leuret, Turner, and Dr. Lonsdale; the last of whom mentions that he could not detect it chemically after the fourth day in the bodies of some animals, in which it was perceptible by its odour even four or five days later.[1931] It is possible, however, that these failures to detect the poison by analysis may have sometimes arisen from imperfections in the method of analysis employed; for it was detected by the process formerly mentioned in the stomach of the apothecary last alluded to, in Chevallier’s case, though not perceptible to the smell, and frequently by Lassaigne in animals.

Mertzdorff remarked both in his case of poisoning with hydrocyanic acid, and likewise in a parallel instance of poisoning with the essential oil of bitter almonds,[1932] a singular appearance in the bile, the colour of which was altered to deep blue.

Coullon and Emmert say they have observed, that the bodies of animals resist putrefaction. The latter in particular mentions, that he had left them several days in a warm room without perceiving any sign of decay. This certainly would not à priori be expected, considering the state of the blood. And it is not universal; for in one instance, the case of Mertzdorff, putrefaction commenced within thirty hours after death. In the Parisian epileptics, the bodies passed through the usual stage of rigidity.

It appears that even long after death the eye, as in Hufeland’s case, has a peculiar glistening and staring expression, so as to render it difficult to believe that the individual is really dead; and this appearance has been considered by Dr. Paris so remarkable, as even alone to supply “decisive evidence of poisoning by hydrocyanic acid.”[1933] But the accuracy of this opinion may be questioned. The appearance is indeed very general in cases of poisoning with preparations containing hydrocyanic acid. Besides occurring in the case of Hufeland, and in that which gave occasion to Dr. Paris’s statement, it was witnessed by Mertzdorff, and in the instance described in Horn’s Journal. But it is not a constant appearance; for it was not observed in the seven Parisian epileptics. Neither is it peculiar; for death from carbonic acid has the same effect; I have remarked it six hours after death in a woman who died of cholera; and it has been observed in cases of death during the epileptic paroxysm.

SECTION IV.—Of the Treatment of Poisoning with Hydrocyanic Acid.

Much attention has been lately paid to the treatment of this variety of poisoning; and the object of those who have studied it has naturally been the discovery of an antidote.

An antidote to hydrocyanic acid must either be a substance which renders it immediately insoluble, or one which exerts upon the body an action contrary to that excited by the poison, that is, a powerful stimulant action on the nervous system. Hence all such remedies as oil, milk, soap, coffee, treacle, turpentine, at one time thought serviceable, are quite inert.[1934]

Antidotes have hitherto been chiefly sought for among the powerful, diffusible stimulants. And it is plain, that even although a chemical antidote were known, a stimulant antidote is indispensable also, because the mischief done, before the poison can be rendered inert, is generally sufficient to cause death, unless counteracted by treatment.

Of the diffusible stimulants, ammonia is considered by many the most energetic antidote. The first who made careful experiments with it was Mr. John Murray of London; and he was so convinced of its efficacy, that he expressed himself ready to swallow a dose of the acid large enough to prove fatal, provided a skilful person were beside him to administer the antidote.[1935] The favourable results obtained by Murray were afterwards confirmed by M. Dupuy.[1936] Afterwards, however, the efficacy of ammonia was called in question. Orfila stated in the third edition of his Toxicology that he had several times satisfied himself of the complete inutility of this as well as many other antidotes.[1937] And Dr. Herbst of Göttingen made some careful experiments, from which he concludes that ammonia, though useful when the dose of poison is not large enough to kill, and even capable of making an animal that has taken a fatal dose jump up and run about for a little, yet will never save its life.[1938] But farther experiments by Orfila have led him to modify his former statement, and to admit, that, although liquid ammonia is of no use when introduced into the stomach, yet if the vapour from it is inhaled, life may sometimes be preserved, provided the dose of the poison be not large enough to act with great rapidity. He remarked, that when from eight to fourteen drops of the medicinal acid were given to dogs of various sizes, they died in the course of fifteen minutes if left without assistance, but were sometimes saved by being made to inhale ammoniacal water, and recovered completely in little more than an hour.[1939] As this is very nearly the conclusion to which Mr. Murray was led by his experiments performed in 1822, it is rather extraordinary, that his name, as the undoubted discoverer of the remedy, has never been mentioned by the Parisian Professor. Buchner, it is right to add, had found this remedy useful in the same year in which Mr. Murray’s experiments were made.[1940] A gentleman who took an over-dose of two drachms of hydrocyanic acid while using it medicinally, and who seems to have been in great danger, owed his recovery to the assiduous use of carbonate of ammonia held to the nostrils, and spirit of ammonia internally. Relief was obtained immediately.[1941] Orfila suggests an important caution,—not to use a strong ammoniacal liquor, otherwise the mouth, air-passages, and even the alimentary canal may be attacked with inflammation,—as indeed happened to the French physician whose case was formerly mentioned. The strong aqua ammoniæ should be diluted with several parts of water.

Another remedy of the same kind with ammonia as to action is chlorine. This substance was first proposed as a remedy in 1822 by Riauz, a chemist of Ulm, who found that, when a pigeon, poisoned with hydrocyanic acid, was on the point of expiring, it immediately began to revive, on being made to breathe chlorine, and in fifteen minutes was able to fly away.[1942] Buchner repeated Riauz’s experiments and arrived at the same results. More lately M. Simeon, apothecary to the hospital of St. Louis at Paris, apparently without being acquainted with the observations of the German chemists, was likewise led to suppose, that this gas might prove a useful antidote;[1943] and MM. Cottereau and Vallette have formed the same conclusion.[1944] Orfila in his paper already quoted expresses his conviction, that this remedy is the most powerful antidote of all hitherto proposed. His experiments have convinced him, that animals, which have taken a dose of poison sufficient to kill them in fifteen or eighteen minutes, will be saved by inspiring water impregnated with a fourth part of its volume of chlorine, even although the application of the remedy be delayed till the poison has operated for four or five minutes. In some of his experiments he waited till the convulsive stage of the poisoning was passed, and the stage of flaccidity and insensibility had supervened; yet the animals were obviously out of danger ten minutes after the chlorine was first applied, and recovered entirely in three-quarters of an hour.[1945]

The last remedy of this nature which deserves notice is the cold affusion. This was first recommended by Dr. Herbst of Göttingen, who, on account of the success he witnessed from it in animals, considers it the best remedy yet proposed. When the dose of the poison was insufficient to prove fatal in ordinary circumstances, two affusions he found commonly sufficient to dispel every unpleasant symptom. When the dose was larger, it was necessary to repeat the effusion more frequently. Its efficacy was always most certain when resorted to before the convulsive stage of the poisoning was over; yet even in the stage of insensibility and paralysis it was sometimes employed with success. In the latter instance the first sign of amendment was renewal of the spasms of the muscles. Many experiments are related by the author in support of these statements. But the most decisive is the following. Two poodles of the same size being selected, hydrocyanic acid was given to one of them in repeated small doses till it died. The whole quantity administered being seven grains of Ittner’s acid, this dose was given at once to the other dog. Immediately it fell down in convulsions, violent opisthotonos ensued, and in half a minute the convulsive stage was followed by flaccidity, imperceptible respiration, and failing pulse. The cold affusion was immediately resorted to, but at first without any amendment. After the second affusion, however, the opisthotonos returned, and was accompanied by cries; and on the remedy being repeated every fifteen minutes, the breathing gradually became easier and easier, the spasms abated, and in a few hours the animal was quite well.[1946] Professor Orfila repeated Dr. Herbst’s experiments, with analogous results; but he considers the cold affusion inferior to chlorine.[1947]—It is probably advantageous to apply the cold water rather in the form of cold douche to the head and spine than to the body at large. Dr. Robinson of Sunderland found that rabbits, which had taken doses adequate to occasion death, might be saved by pouring on the hindhead and along the spine cold water impregnated with common salt and nitre.[1948] A case, which seems to have been cured in this way, has been published by Mr. Banks of Lowth. A young woman took by mistake a solution containing very nearly a grain of real acid, and immediately became insensible and convulsed. Ordinary stimulants were of no use. But in fifteen minutes, when the convulsions had ceased, and she lay in a state of complete coma and general paralysis, the cold douche on the head first renewed the convulsions, then strengthened the pulse and restored some appearance of consciousness, and finally roused her, so that in a few hours she was quite well.[1949]

It is probable, that bleeding from the jugular vein deserves more attention as a remedy than it has yet received. The right side of the heart is almost invariably found much gorged with blood in animals examined at the moment of death; and the contractions of the heart, in such circumstances imperfect or arrested altogether, have often been observed by experimentalists to be instantly restored on promptly removing the state of turgescence. Accordingly Dr. Cormack found that a dog, at the point of death after receiving a fatal dose of the acid, was speedily roused and eventually saved by bleeding from the jugular vein.[1950] And in a careful inquiry by Dr. Lonsdale, it was ascertained that the turgescence of the heart might be effectually diminished in this way, and that recovery might frequently be accomplished when the poison was otherwise amply sufficient to have occasioned speedy death.[1951] In a case treated by Magendie, that of a young lady poisoned by too large a medicinal dose, the chief remedies were ammonia and blood-letting from the jugular vein; and she recovered.[1952]

Few observations have hitherto been made on the chemical antidotes for hydrocyanic acid, or those substances which render it innoxious by converting it into an insoluble compound. It is plain that several probable antidotes of this kind exist. But toxicologists have been apparently deterred from trying them by the fearful rapidity with which the poison acts, and the consequent improbability that in practice any such antidote can be administered in time. It has lately been shown, however, by Messrs. T. and H. Smith of this city, that the effects of a fatal dose may be warded off by the timely administration of the reagents necessary for converting the acid into Prussian blue. They found that if a solution of carbonate of potash followed by a solution of the mixed sulphates of iron be given to animals very soon after the administration of a dose of thirty drops of the Edinburgh medicinal acid, containing three per cent. of real acid, recovery in general takes place, and sometimes little inconvenience seems to be sustained. The solutions they used were one of 144 grains of carbonate of potash in two ounces of water, and another composed of a drachm and a half of sulphate of protoxide of iron, together with two drachms of the same salt converted into sulphate of sesquioxide by means of sulphuric and nitric acids in the usual way. About 52 minims of each of these solutions will remove the whole acid contained in 100 grains of the Edinburgh medicinal acid; but for certainty, three or four times as much should be used,—which may be done with perfect safety.[1953]

On the whole, then, it appears that the proper treatment of a case of poisoning with hydrocyanic acid consists in the cold affusion applied to the head and spine, the inhalation of diluted ammonia or chlorine, venesection at the jugular vein, and the administration of carbonate of potash and the mixed sulphates of iron, if aid has been obtained in good time.

It is right to remember, however, that on account of the dreadful rapidity of this variety of poisoning, it will rarely be in the physician’s power to resort to any treatment soon enough for success;—and farther, that his chance of success must generally be feeble even though the case be taken in time, because when hydrocyanic acid is swallowed by man, the dose is commonly so large as not to be counteracted by any remedies.

On the Vegetable Substances which contain Hydrocyanic Acid.

Hydrocyanic acid exists in several plants; which are consequently poisonous. I have considered it advisable to describe their effects separately from those of the pure acid.

The plants which have been thoroughly examined and found to yield it belong chiefly to the division Drupaceæ, of Decandolle’s Natural Family the Rosaceæ. These are the bitter almond, cherry-laurel, bird-cherry, and peach. The leaves and seeds of the nectarine and apricot, and the seeds of the plum and cherry, have the same taste with these four, and therefore will certainly be found to contain the acid also. The same inference may be drawn from the taste of some pomaceous seeds; and accordingly I have obtained a hydrocyanated oil from the seeds of the New York pippin, and those of the white-beam-tree, the Pyrus aria. The poison procured from these sources exists in two forms,—as a distilled water, and as an essential oil. Further, the acid has been discovered to constitute the active poison of the juice of the Janipha manihot, or bitter cassava [see p. 457].

The distilled waters yield hydrocyanic acid, as is shown by the blue precipitate they give with potass and the mixed sulphates of iron. They have a powerful, peculiar, grateful odour, which is usually likened to that of pure hydrocyanic acid. But the smell really bears very little resemblance to that of hydrocyanic acid, and is not owing to its presence: the odour remains equally strong after the acid is thrown down by the test now mentioned. The active part of the distilled water may be separated in the form of a volatile oil. This is colourless at first, afterwards yellowish or reddish, acrid, bitter, heavier than water, and very volatile. The essential oil of the bitter almond has been carefully examined by various chemists. Vogel, by subjecting it twice to distillation from caustic potass, procured hydrocyanate of potass in the residue; and a volatile oil was distilled over, which no longer contained hydrocyanic acid, but nevertheless had the odour of the original oil.[1954] This purified oil he considered equally poisonous with that which contains hydrocyanic acid, a single drop of it having killed a sparrow; and his opinion was confirmed by the experiments of Professor Orfila. But according to some careful experiments by Stange,[1955] which have been amply confirmed by Dr. Göppert of Breslau,[1956] and also by MM. Robiquet and Boutron-Charlard,[1957]—if the purified oil retains active poisonous properties, this must be owing to the acid not having been entirely removed. Göppert in particular remarked that twenty-five drops of the purified bitter-almond oil, cherry-laurel oil, or bird-cherry oil had very little effect on rabbits, not more indeed than the same quantity of the common essential oils. The purified oil, according to all these chemists, possesses the odour of the original oil, as Vogel first stated.

Of the Bitter Almond.

The bitter almond was once extensively used in medicine, and is still much employed by confectioners for flavouring puddings, sweetmeats, and liqueurs. It is the kernel of the fruit of the Amygdalus communis. This species has two varieties, the dulcis and the amara; which differ from one another in the fruit only. The fruit of the former yields the sweet, and of the latter the bitter almond. The bitter almond is the smaller of the two. The two plants, according to Murray, are convertible into each other,—the sweet variety becoming bitter by neglect,—the bitter becoming sweet by cultivation, or certain modes of management not well known,—and the seed of either variety producing plants of both.[1958] These statements as to the mutual convertibility of the two varieties require confirmation.

The bitter almond depends for its activity on the essential oil, which is common to all the vegetable poisons belonging to the present tribe. According to the researches of Robiquet and Boutron-Charlard, followed up by Liebig, the oil does not, like common essential oils, exist ready formed in the almond, but is only produced when the almond-pulp comes in contact with water. It cannot be separated by any process whatever from the almond without the co-operation of water,—neither, for example, by pressing out the fixed oil, nor by the action of ether, nor by the action of absolute alcohol. After the almond is exhausted by ether, the remaining pulp gives the essential oil as soon as it is moistened; but if it is also exhausted by alcohol, the essential oil is entirely lost. The reason is that alcohol dissolves out a peculiar crystalline principle, named amygdalin, which, with the co-operation of water, forms the essential oil by reacting on a variety of the albuminous principle in the almond, called emulsion or synoptase.

In some respects, therefore, the essential oil of almonds is quite peculiar in its nature, and quite different from the common essential or volatile oils.—The presence of hydrocyanic acid in it is easily proved by dissolving it with agitation in water, and treating the solution with caustic potass, followed by the mixed sulphates of iron and sulphuric acid.—The quantity of essential oil which may be procured from the bitter almond amounts, according to Krüger of Rostock, to four drachms from five pounds or a ninety-sixth part.[1959] The quantity of hydrocyanic acid in the oil varies considerably: Schrader got from an old sample 8·5 per cent., from a new sample 10·75;[1960] but Göppert got from another specimen so much as 14·33 per cent.[1961]

Effects on Animals.—The bitter almond is a powerful poison, which acts in the same way as hydrocyanic acid, but likewise excites at times vomiting and other signs of irritation. The first good experiments on it are those related in Wepfer’s treatise on the Cicuta; but its properties seem to have been known even to Dioscorides. The symptoms it induces in animals are trembling, weakness, palsy, convulsions, often of the tetanic kind, and finally coma. But frequently it occasions vomiting before these symptoms begin, and the animal in that way may escape.[1962] According to Orfila, twenty almonds will kill a dog in six hours by the stomach if the gullet be tied; and six will kill it in four days when applied to a wound.[1963]

The essential oil is not much inferior in activity to the pure hydrocyanic acid. A single drop of it applied by Sir B. Brodie on the tongue of a cat caused violent convulsions and death in five minutes.[1964] But more generally a larger dose, or about seven drops, has been found necessary to kill a middle-sized dog. Five drops, according to Göppert, will kill a rabbit in six minutes. When entirely freed of hydrocyanic acid, it becomes, as already mentioned, not more poisonous than common volatile oils.

Symptoms in Man.—The effects of the almond and of the oil upon man are equally striking with those of hydrocyanic acid.

In small doses the bitter almond produces disorder of the digestive organs, nausea, vomiting, and sometimes diarrhœa. These symptoms are occasionally brought on by the small quantities used for flavouring sweetmeats, if the confectioner has not been careful in compounding them. Virey says that accidents occasionally happen to children at Paris from their eating freely of macaroons, which are sometimes too strongly flavoured with the bitter almond.[1965] In this country accidents from the same cause may be with justice apprehended, as confectioners now generally use, not the bitter almond, but its essential oil, which is distilled for the purpose in London, and sold in the druggists shops under the name of peach-nut oil. Göppert suggests that this oil ought to be freed of its hydrocyanic acid by repeated distillation with caustic potassa, because the flavour is not in the least injured by the process, while its activity as a poison is greatly lessened.

In peculiar constitutions the minutest quantity, even a single almond, will cause a state resembling intoxication, succeeded by an eruption like nettle-rash. The late Dr. Gregory was subject to be affected in this way. Other vegetable bitters had the same effect on him, but none so remarkably as bitter almonds. They caused first sickness, generally tremors, then vomiting, next a hot fit with an eruption of urticaria, particularly on the upper part of the body. At the same time the face, and head swelled very much, and there was generally a feeling like intoxication. The symptoms lasted only for a few hours. The rash did not alternately appear and disappear as in common nettle-rash.[1966] A lady of my acquaintance is liable to be attacked with urticaria even from eating the sweet almond.

The quantity of bitter almonds which may be eaten with impunity is unknown; but Wibmer mentions an experimentalist who took half an ounce without any other effect besides headache and sickness.[1967] Two cases of death in the human subject from eating them have been quoted by Coullon from the Journal de Médecine of Montpellier. One is a doubtful case, but the other is unequivocal. A bath-woman gave her child the “expressed juice” of a handful of bitter almonds to cure worms. The child, who was four years old, was immediately attacked with colic, swelling of the belly, giddiness, locked jaw, frothing at the mouth, general convulsions, and insensibility, and died in two hours.[1968] Murray, however, asserts in his Apparatus Medicaminum that the expressed juice is sweet and not poisonous.[1969] But this apparent contradiction is easily explained by referring to the chemical relations of the almond,—the oil expressed without water being free from essential oil, while the milky fluid expressed from the pulp beat up with water is strongly impregnated with it.—Another case was published not long ago by Mr. Kennedy of London; but the symptoms were imperfectly ascertained. The person, a stout labourer, appeared to have eaten a great quantity of bitter almonds, which were subsequently found in the stomach. He was seen to drop down while standing near a wall; soon after which the surgeon who was sent for found him quite insensible, with the pulse imperceptible, and the breath exhaling the odour of bitter almonds; and death took place in no long time.[1970]

Coullon has noticed many other instances where alarming symptoms were produced by this poison, but were dissipated by the supervention of spontaneous vomiting.

The effects of small doses of the oil have been tried by Sir B. Brodie on himself; and a fatal case of poisoning with it has been recorded by Mertzdorff. In the course of his experiments Sir B. Brodie once happened to touch his tongue with the end of a glass rod which happened to be dipped in the oil; and he says he had scarcely done so before he felt an uneasy, indescribable feeling in the pit of the stomach, great feebleness of his limbs, and loss of power to direct the muscles, so that he could hardly keep himself from falling. These sensations were quite momentary.[1971]

Mertzdorff’s case is interesting, not only as being accurately related, but likewise on account of the exact resemblance of the symptoms to those observed in the celebrated case of Sir Theodosius Boughton, which will presently be mentioned. A hypochondriacal gentleman, 48 years old, swallowed two drachms of the essential oil. A few minutes afterwards, his servant, whom he sent for, found him lying in bed, with his features spasmodically contracted, his eyes fixed, staring, and turned upwards, and his chest heaving convulsively and hurriedly. A physician, who entered the room twenty minutes after the draught had been taken, found him quite insensible, the pupils immoveable, the breathing stertorous and slow, the pulse feeble and only 30 in a minute, and the breath strongly impregnated with the odour of bitter almonds, death ensued ten minutes afterwards.[1972] A fatal case occurred lately in London, where the individual, intending to compound a nostrum for worms with beech-nut oil, got by mistake from the druggist peach-nut oil, which is nothing else than the oil of bitter almond.—A singular case of recovery from a very large dose of this poison has been lately published by M. Chevasse. A shopkeeper, who swallowed half an ounce by mistake for spirit of nitric ether, had an attack of spontaneous vomiting, which was forthwith encouraged by sulphate of zinc. He nevertheless became pale and convulsed; the pulse disappeared; and delirious muttering ensued, with risus sardonicus, sparkling of the eyes, and panting respiration. Recovery, however, took place under the use of brandy and ammonia.[1973]

The morbid appearances are the same as in poisoning with the pure acid. In Mertzdorff’s case the whole blood and body emitted a smell of almonds; putrefaction had begun, though the inspection was made twenty-nine hours after death; the blood throughout was fluid, and flowed from the nostrils and mouth; the veins were every where turgid; the cerebral vessels gorged; the stomach and intestines very red.—In the case from the Medical and Physical Journal of poisoning with the almond itself, the vessels of the brain were much gorged, and the eyes glistening and staring as if the person had been alive.

Of the Cherry-Laurel.

The cherry-laurel, or Cerasus lauro-cerasus, was at one time much used for flavouring liqueurs and sweetmeats. But it is now less employed than formerly, as fatal accidents have happened from its having been used in too large quantity. The custom, however, has not been altogether abandoned; for there is an account in an English newspaper in 1823 of two persons killed by ratifia’d brandy, which had been flavoured with this plant; and Dr. Paris has mentioned an instance of several children at an English boarding-school having been dangerously affected by a custard flavoured with the leaves.[1974] Almost every part of the plant is poisonous, especially the leaves and kernels; but the pulp of the cherry is not. The flower has a totally different odour from the leaves. The healthy vigorous shoots in the early part of summer, and the inner bark, both then and in autumn, smell strongly of the bitter almond when broken across. The kernels of the seeds have a strong taste of bitter almonds.—The plant yields a distilled water and an essential oil, which Robiquet found to have all the chemical properties of the oil of bitter almond.[1975]—A very peculiar source of danger in using the leaves of this plant, for imparting a ratafia flavour to sweetmeats and liqueurs, is that the proportion of oil varies excessively according to the age of the leaf. It abounds most in the young undeveloped leaves, and diminishes gradually afterwards. Hence, the leaves being evergreen and outliving more than two summers, the young leaves in May or June contain, as I have found, nearly ten times as much oil as the old ones at the same moment.

Cherry-laurel oil, according to Schrader, contains 7·66 per cent. of hydrocyanic acid;[1976] but according to Göppert, a specimen supposed to be genuine gave only 2·75 per cent.[1977] It is probably therefore a weaker poison than the oil of bitter almond. The latest experiments made with this oil are those of some Florentine physicians, performed at the laboratory of the Marquess Rodolphi, and described by Professor Taddei.[1978] Sixteen drops put on the tongue of rabbits killed them in nine, fifteen, or twenty minutes; and ten or twelve drops injected in oil into the anus killed them in four minutes. The symptoms were slow breathing, palsy of the hind-legs, then general convulsions; and death was preceded by complete coma. A very extraordinary appearance was found in the dead body,—blood extravasated abundantly in the trachea and lungs.

The cherry-laurel water, prepared by distillation from the leaves of this plant, was long the most important of the poisons which contain the hydrocyanic acid, as it was the most common before the introduction of the acid itself into medical practice. Water dissolves by agitation 3·25 grains of oil per ounce; which may be considered the proportion in a saturated distilled water. The water contains, according to Schubarth, only 0·25 per cent. of hydrocyanic acid;[1979] according to Schrader[1980] only half as much; and by long keeping even that small proportion will gradually disappear, as I have ascertained by experiment. Hence its strength must vary greatly,—a fact which will explain the very different effects of the same dose in different instances.

From experiments on animals by a great number of observers, it appears that, whether it is introduced into the stomach, or into the anus, or into the cellular tissue, or directly into a vein, it occasions giddiness, palsy, insensibility, convulsions, coma, and speedy death;—that the tetanic state brought on by the pure acid, is not always so distinctly caused by cherry-laurel water;—and that tetanus is most frequently induced by medium doses.

The attention of physicians was first called to this poison by an account, published by Dr. Madden in the Philosophical Transactions for 1737, of several accidents which occurred at Dublin in consequence of strong ratifia’d brandy having been prepared with it. Foderé has also given an account of two cases, caused by servants having stolen and drunk a bottle of it, which they mistook for a cordial.[1981] Being afraid of detection, they swallowed it quickly, and in a few minutes expired in convulsions. Murray has noticed several others in his Apparatus Medicaminum.[1982] In most of these cases the individuals suddenly lost their speech, fell down insensible, and died in a few minutes. Convulsions do not appear to have been frequent. Coullon has also related an instance where a child seems to have been killed by the leaves applied to a large sore on the neck.[1983]

The dose required to occasion these effects, and more especially to prove fatal, has not been determined with care. It must vary with the age of the sample used. It will vary also according as the water has been filtered or not; for what is not filtered often presents undissolved oil suspended in it or floating on its surface. One ounce has proved fatal;[1984] and half an ounce has caused only temporary giddiness, loss of power over the limbs, stupor, and sense of pressure in the stomach.[1985]

The appearances found in the dead body have varied. In general the blood has been fluid. The smell of bitter almond has commonly been distinct in the stomach.

The cherry-laurel water has attracted much attention in this country, in consequence of being the poison used by Captain Donnellan for the murder of Sir Theodosius Boughton. The trial of Donnellan, the most important trial for poisoning which ever took place in Britain, has given rise to some discrepance of opinion both among barristers and medical men, as to the sufficiency of the evidence by which the prisoner was condemned.[1986] For my part, taking into account the general, as well as medical circumstances of the case, I do not entertain a doubt of his guilt.

Leaving the general evidence out of view, however, as foreign to the objects of the medical jurist’s regard, it must be admitted that the medical evidence, taken by itself, was defective. It may be summed up shortly in the following terms:—Sir Theodosius was a young man of the age of twenty, and in perfect health, except that he had a slight venereal complaint of old standing, for which he occasionally took a laxative draught. On the morning of his death, his mother, Lady Boughton, remarked, while giving him his draught, that it had a strong smell of bitter almonds. Two minutes after he took it, she observed a rattling or gurgling in his stomach; in ten minutes more he seemed inclined to doze; and five minutes afterwards she found him quite insensible, with the eyes fixed upwards, the teeth locked, froth running out of his mouth, and a great heaving at his stomach and gurgling in his throat. He died within half an hour after swallowing the draught. The body was examined ten days after death, and the inspectors found great congestion of the veins every where, gorging of the lungs, and redness of the stomach. But the examination was unskilfully conducted. For the head was not opened; the fæces were allowed to rush from the intestines into the stomach; and, as a great quantity of fluid blood was found in each cavity of the chest, the subclavian veins must have been divided during the separation of the clavicles. Very little reliance, therefore, can be placed in the evidence from the inspection of the body.[1987]

On comparing these particulars with what has been said above regarding the effects of hydrocyanic acid and this whole genus of poisons, it will be seen that every circumstance coincides precisely with the supposition of poisoning with the cherry-laurel water. The symptoms were exactly the same as in Mertzdoff’s case of poisoning with the essential oil of almonds (p. 604). When to this are added, the smell of the draught, which Lady Boughton could hardly mistake, the rarity of apoplexy in so young and healthy a person as Sir Theodosius, and the improbability of either that or any other disease of the head proving fatal so quickly,—the conclusion at which, in my opinion, every sound medical jurist must arrive is, that poisoning in the way supposed was very probable. But I cannot go along with those who think that it was certain; nor is it possible to see on what grounds such an opinion can be founded, when the general or moral circumstances are excluded.

The medical evidence in Donnellan’s case has been much canvassed, and especially that of Mr. John Hunter. It would be foreign to the plan hitherto pursued in this work to analyze and review what was said by him and his brethren. But I must frankly observe, that Mr. Hunter’s evidence does him very little credit, and that his high professional eminence is the reverse of a reason for palliating his errors, or treating them with the lenity which they have experienced from his numerous critics.

Of the Peach, Cluster-Cherry, Mountain-Ash, &c.

Little need be said of the other plants formerly mentioned among those which yield hydrocyanic acid, and act on the system in consequence of containing that substance.

The Amygdalus persica or peach is the most active of them. Most parts of the plant exhale the odour of the bitter-almond, but particularly the flowers and kernels. According to the chemical researches of M. Gauthier, the fresh young shoots of the peach collected in July contain, weight for weight, even more essential oil than the bitter almond, or cherry-laurel leaves; for 250 grains yielded nearly five grains of it or two per cent.; and he found the oil may be easily procured by distilling the shoots without addition till the product begins to pass over clear.[1988] The kernels of the peach, when distilled with water, yield nearly one grain of hydrocyanic acid per ounce.[1989]

Coullon has collected two instances of poisoning with the peach-blossom. One is the case of an elderly gentleman, who swallowed a sallad of the flower to purge himself. Soon afterwards he was seized with giddiness, violent purging, convulsions, and stupor; and he died in three days. Here the poison must have proved fatal by inducing true apoplexy in a predisposed habit; at least poisoning with hydrocyanic acid never lasts nearly so long. The other, a child eighteen months old, after taking a decoction of the flowers to destroy worms, perished with frightful convulsions, efforts to vomit, and bloody diarrhœa.[1990] The peach-blossom would therefore appear to be rather a narcotico-acrid, than a narcotic.—Peach-leaves are represented to have produced even purely irritant effects. A man, who took a decoction of a handful boiled in a quart of water down to a third,—when of course no hydrocyanic acid could remain,—was attacked with tightness in the chest, a sense of suffocation, violent colic, pain in the stomach and frequent desire to vomit, followed by a hard pulse, restlessness, and flushing of the face. But he recovered slowly under the use of fomentations and opiates.[1991]

The bark of the Prunus padus, or cluster-cherry, a native of this country, owes its poisonous qualities to the same substance as the preceding plants. Heumann found that the distilled water obtained from two ounces of bark in March contains two grains of acid, two ounces of developed leaves half a grain, and two ounces of the seed a trifle less.[1992] Its distilled water has the odour of bitter almonds, contains the same essential oil with that of the bitter almond, and yields more hydrocyanic acid than the cherry-laurel water.[1993] The oil, according to Schrader, contains 9·25[1994] per cent. of hydrocyanic acid, according to Göppert only 5·5 per cent.[1995] Bremer, who has examined this plant with great care, found that both the distilled water and the essential oil kill mice when put into the mouth, eye, nose, ear, anus, or a wound; and that half an ounce of the water killed a dog in twelve minutes.[1996] The fruit is also poisonous. It has a nauseous taste, but communicates a pleasant flavour to spirituous liquors. The kernels yield by expression a transparent, fixed oil, concrete at 41° F., which contains a small quantity of the essential oil; and the cake which is left yields so much of the latter, that, as we are informed by M. Chancel of Briançon, a handful has proved fatal to cows in a short time.[1997] In these kernels, as in the bitter almond, the essential oil does not exist ready formed, but is developed only in consequence of the contact of water; and hence, if the fixed oil by expression contains a little of it, as Chancel says, this must arise from the kernels having been moist when squeezed.

The Sorbus aucuparia, mountain-ash, or Rowan-tree as it is called in Scotland, has been lately added to the list of plants which abound in the same poisonous principle. M. Grassmann of St Petersburgh has found that many parts of this tree, such as the flowers and the bark of the trunk and branches, contain more or less of the peculiar essential oil; and that the root in particular contains so much in the month of May as to smell strongly of it when broken across, and to yield a distilled water which holds fully as much hydrocyanic acid as that procured from an equal weight of cherry-laurel leaves.[1998]

Several other plants of the same natural order possess similar though weaker properties, such as the Prunus avium, or black-cherry, or mazzard, the Prunus insititia, or bullace, the Prunus spinosa, or sloe, the Amygdalus nana, or dwarf-almond, and even the leaves and kernels of the common cherry, the Cerasus communis. Twelve ounces of cherry kernels distilled with water, yield, according to Geiseler, seven grains of hydrocyanic acid.[1999] I have no doubt, from my experiments, that the seeds of Pyrus malus, the apple, Pyrus aria, the white-beam, and also, if the taste may be taken for a criterion, the whole seeds of the Pomaceæ, yield by distillation with water a large quantity of hydrocyanic acid.

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XXX. OF POISONING WITH CARBAZOTIC ACID

A substance long known to chemists by the name of indigo-bitter, which is procured by the action of nitric acid on indigo, silk, and other azotized substances, and which has been found to consist chiefly of a peculiar acid, termed by Liebig, from its composition, the carbazotic acid, appears to be a pure narcotic poison of considerable activity.[2000] It is in the form of shining crystals, of an excessively bitter taste, and of a yellow colour so singularly intense that it imparts a perceptible tint to a million parts of water. The pure crystals are composed of carbon, azote, and oxygen.

The only account I have seen of the physiological properties of this substance is a full analysis by Buchner in his Toxicology, of some interesting experiments by Professor Rapp of Tübingen.[2001] He found that sixteen grains in solution, when introduced into the stomach, killed a fox, ten grains a dog, and five grains a rabbit, in an hour and a half; that the injection of a watery solution into the windpipe occasioned death in a few minutes; that the introduction of it into the cavity of the pleura or peritonæum occasioned death in several hours; that a watery solution of ten grains injected into the jugular vein of a fox killed it instantaneously, and in like manner five grains affected a dog in three minutes and killed it in twenty-four hours; and that thirty grains applied to a wound killed a rabbit. The symptoms remarked from its introduction into the stomach of the fox were in half an hour tremors, grinding of the teeth, constant contortion of the eyes and convulsions, in an hour complete insensibility, and death in half an hour more. In the dog there was also remarked an attack of vomiting and feebleness of the pulse.

In the dead body no particular alteration of structure was remarked. The heart, examined immediately after death from the introduction of the poison into the stomach, was found much gorged and motionless; but the irritability of the voluntary muscles remained. The stomach was not inflamed, but dyed yellow. A very interesting appearance was dyeing of various textures and fluids throughout the body. In the fox killed by swallowing sixteen grains the conjunctiva of the eyes, the aqueous humour, the capsule of the lens, the membranes of the arteries, in a less degree those of the veins, the lungs, and in many places the cellular tissue, had acquired a lemon-yellow colour. The dog killed in the same manner presented similar appearances, also those killed by injection of the poison into the pleura or peritonæum; and in the latter animals the urine was tinged yellow. In a rabbit killed by the application of the poison to a wound the same discoloration was also every where remarked, together with yellowness of the fibrin of the blood. But no yellowness could be seen any where in the dog, which died in twenty-four hours after receiving five grains into the jugular vein. In no instance was there any yellow tint perceptible in the brain or spinal cord.

These facts form an interesting addition to the physiology of poisons. They supply unequivocal proof that this substance is absorbed in the course of its operation, and furnish strong presumption that other poisons, which act on organs remote from the place where they are applied, and which have been sought for without success in the blood, as well as in other fluids and solids throughout the body, have not been detected, merely because the physiologist does not possess such simple and extremely delicate means of searching for them.

The researches of Professor Rapp have been arranged under the title of carbazotic acid, because this acid forms the most prominent substance in the matter with which his experiments appear to have been made. But it is right to state, that the article actually used was, if I understand correctly the abstract given by Buchner, not the pure crystals, but the yellow fluid, from which the crystals are procured, and which contains also a resinous matter and artificial tannin.—The bitter principle of Welther produced by the action of nitric acid on silk, and that formed by Braconnot by the action of the same acid on aloes, appear to be impure carbazotic acid.

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XXXI. OF THE POISONOUS GASES

The subject of the poisonous gases is one of great importance in relation to medical police, as well as medical jurisprudence. They are objects of interest to the medical jurist, because their effects may be mistaken for those of criminal violence, and because they have even been resorted to for committing suicide. They are interesting as a topic of medical police, since some trades expose the workmen to their influence.

It has hitherto been chiefly on the continent that use has been made of the deleterious gases for the purpose of self-destruction. Osiander mentions, that Lebrun, a famous player on the horn, suffocated himself at Paris in 1809 with the fumes of sulphur; and that an apothecary at Pyrmont killed himself by going into the Grotto del Cane there, which, like that near Naples, is filled with carbonic acid gas.[2002] Many instances have lately occurred in France of suicide caused by the emanations from burning charcoal in a close chamber.

But these poisons come under the notice of the medical jurist chiefly because their effects may be mistaken for those of other kinds of violent death. Several mistakes of this nature are on record. Zacchias mentions the case of a man, who was found dead in prison under circumstances which led to the suspicion, that he had been privately strangled by the governor. But Zacchias proved this to be impossible, and ascribed death to the fumes from a choffer of burning charcoal left in the room.[2003] A more striking instance of the kind occurred a few years ago at London. A woman, who inhabited a room with other five people, alarmed the neighbours one morning with the intelligence that all her fellow-lodgers were dead. On entering the room they found two men and two women actually dead, and another man quite insensible and apparently dying. This man, however, recovered; and as it was said that he was too intimate with the woman who gave the alarm, a report was spread that she had poisoned the rest, to get rid of the man’s wife, one of the sufferers. She was accordingly put in prison, various articles in the house were carefully analysed for poison, and an account of the supposed barbarous murder was hawked about the streets. At last the man who recovered remembered having put a choffer of coals between the two beds, which held the whole six people; and the chamber having no vent, they had thus been all suffocated.[2004]—The following is a similar accident not less remarkable in its circumstances. Four people in Gerolzhofen in Bavaria, were found one morning in bed, some dead, others comatose; and only one recovered. A neighbour who had supped with them, but slept at home, did not suffer. The stomach and intestines were found very red and black; and the coats of the stomach brittle. The contents of the stomach, the remains of their supper, and the wine were analysed without any suspicious substance being found. A little smoke having been noticed in the room by those who first entered it, the stove and fuel were examined, but without furnishing any insight into the cause of the accident. At last the cellar was examined, and then it was found that one of the sufferers had heated a copper vessel there so incautiously, that the fire communicated with the unplastered planks of the floor above. The planks had burnt with a low smothered flame, and the vapours passed through the crevices in the floor.[2005]

What Irrespirable Gases are Poisonous?

Some gases act negatively on the animal system by preventing the access of respirable air to the lungs; others are positively poisonous. The first point, therefore, is to ascertain which are negatively, and which positively hurtful.

M. Nysten, who has made the most connected train of experiments on this subject, conceived that a gas will not act through any other channel besides the lungs, if it exerts merely a negative action:—and that, on the contrary, it certainly possesses a direct and positive power, if it has nearly the same effects, in whatever way it is introduced into the body.[2006] He therefore thought the best way to ascertain the action of the gases would be, to inject them into the blood,—conceiving that, after allowance is made for the mere mechanical effects of an aëriform body, the phenomena would point out the true operation of each.

His first object then was to learn what phenomena are caused by the mechanical action of atmospheric air. He found that four cubic inches and a half, injected into the jugular vein of a dog, killed it immediately amidst tetanic convulsions, by distending the heart with frothy blood;—that a larger quantity introduced, gradually caused more lingering death, with symptoms of oppressed breathing, which arose from gorging of the lungs with frothy blood;—and that a small quantity, injected into the carotid artery towards the brain, occasioned speedy death by apoplexy, which arose from the brain being deprived by means of the air of a due supply of its proper stimulus, the blood. Numerous experimental inquiries have been since made on this subject, the latest of which, those of Dr. Cormack, coincide with the first results of Nysten, that air injected into the veins causes death by arrestment of the action of the heart.[2007]

Proceeding with these data, Nysten found that oxygen and azote had the same effect when apart, as when united in the form of atmospheric air; that carburetted hydrogen, hydrogen, carbonic oxide, and phosphuretted hydrogen likewise seemed to act in the same way; and that the nitrous oxide, or intoxicating gas, although it does not cause so much mechanical injury as the others, on account of its superior solubility in the blood, has the same effect when injected in sufficient quantity, and produces little or none of the symptoms of intoxication excited by it in man.[2008] As to carbonic acid gas, he found that, on account of its great solubility in the blood, it is difficult to produce mechanical injury with it; that sixty-four cubic inches are absorbed, and do not excite any particular symptoms; but that when injected into the carotid artery, it occasions death by apoplexy, although it is rapidly absorbed by the blood.[2009]

The other gases he tried were hydrosulphuric acid, nitric oxide, ammonia and chlorine; and all of these proved to be positively and highly deleterious.

Two or three cubic inches of hydrosulphuric acid gas caused tetanus and immediate death, when injected into the veins, although the gas was at once absorbed by the blood. The same quantity acted with almost equal rapidity when injected into the cavity of the chest. Similar results were obtained when it was injected into the cellular tissue, or even when it was left for some time in contact with the sound skin.[2010] The last important fact has been since confirmed by Lebküchner in his Thesis on the permeability of the tissues;[2011] and it had previously been observed also by the late Professor Chaussier, whose experiments will be mentioned presently (p. 617). In none of Nysten’s experiments with this gas was the blood changed in appearance.

Nitric oxide gas, according to Nysten, is the most energetic of all the poisonous gases. A very small quantity causes death by tetanus, when introduced into a vein, the cavity of the chest, or the cellular tissue; and it always changes the state of the blood, giving it a chocolate-brown colour, and preventing its coagulation. In one of Nysten’s experiments a cubic inch and three-quarters injected into the chest killed a little dog in 45 minutes.[2012] Dr. John Davy appears to have found this gas not so active.[2013]

Nysten found the two other gases, ammonia and chlorine, to be acrid in their action. When injected into the veins they kill by over-stimulating the heart; and when injected into the cavity of the chest, they excite inflammation in the lining membrane.[2014] Hébréart farther remarked in his experiments relative to the action of irritants on the windpipe, that chlorine when inspired, produces violent inflammation in the windpipe and its great branches, ending in the secretion of a pseudo-membrane like that of croup;[2015] and that a very small quantity of ammonia has the same effect.

From this abstract of Nysten’s researches, it appears to follow, that ammonia and chlorine are irritants; hydrosulphuric acid and nitric oxide, narcotics; oxygen, azote, hydrogen, carburetted hydrogen, phosphuretted hydrogen, carbonic oxide, and nitrous oxide, negative poisons; and carbonic acid, doubtful in its nature. Some of these conclusions do not correspond with the effects observed in man; which will presently be found to lead to the inference, that not only carbonic acid, but likewise carbonic oxide, nitrous oxide, and carburetted hydrogen are narcotics. The reason Nysten did not find these gases injurious was probably, that, before they could pass from the vein into which they were injected, to the brain on which they act, they were in a great measure exhaled from the lungs. The experiments of physiologists since Nysten’s time likewise tend to show that oxygen gas is a positive poison when pure, and that even hydrogen possesses active properties. The inquiries of Mr. Broughton led him to consider hydrogen a positive poison, because animals die in it in half a minute, and the heart immediately after death is found to have lost its contractility. Previous experimentalists had also remarked hypnotic effects from the inhalation of it diluted with oxygen.[2016] As to oxygen, the same physiologist ascertained that when pure, it is a narcotic poison, though a feeble one, as at least five hours of continuous respiration in the pure gas are required to prove fatal.[2017]

Of the Effects of the Poisonous Gases on Man.

According to the effects of the poisonous gases on man, they may be arranged in two groups, the first including the irritants, the second the narcotics. It might have been therefore a more philosophical mode of arrangement, if the former had been considered under the irritant class of poisons; but it is more convenient to examine the whole deleterious gases together.

The irritant gases are nitric oxide gas and nitrous acid vapour, hydrochloric acid gas, chlorine, ammonia, sulphurous acid, and some others of little consequence.

Of Nitric oxide gas and Nitrous acid vapour.—Before nitric oxide gas can be breathed in ordinary circumstances, it is transformed by the oxygen of the air into nitrous acid vapour, of a ruddy colour and irritating odour. Hébréart found that in animals killed by inhaling it the windpipe was much inflamed.[2018] Sir H. Davy tried to inhale it, and with this view took the precaution of previously breathing the nitrous oxide or intoxicating gas, in order to expel the atmospheric air as much as possible from his lungs. But he found that the small quantity of nitrous acid fumes formed with the remaining air was sufficient to cause a sense of burning in the throat, and at once stimulated the glottis to contract, so that none of the nitric oxide gas could pass into the larynx. The subsequent entrance of the external air into the mouth, which Sir Humphrey unluckily had not provided for, was of course attended by the immediate formation of more acid fumes, by which his tongue, cheeks, and gums, were irritated and inflamed; and there is no doubt, as Sir Humphrey himself remarks, that if he had succeeded in inhaling the nitric oxide gas, the same chemical change would have happened in the lungs and excited pneumonia.[2019]

The following cases will prove that nitrous acid vapour, disengaged from the fuming nitrous acid, is a very violent and dangerous poison when inhaled. A chemical manufacturer, in endeavouring to remove from his store-room a hamper in which some bottles of nitrous acid had burst, breathed the fumes for some time, and was seized in four hours with symptoms of inflammation in the throat and stomach. At night the urine was suppressed; the skin then became blue; at last he was seized with hiccup, acute pain in the diaphragm, convulsions, and delirium; and he died twenty-seven hours after the accident.[2020] Another case has been described in the Bulletins of the Medical Society of Emulation. It proved fatal in two days, and the symptoms were those of violent pneumonia. In this instance there was pneumonia of one side, and pleurisy of the other; the uvula and throat were gangrenous, and the windpipe and air-tubes dark-red; the veins throughout the whole body were much congested, the skin very livid in many places, and the blood fluid in the heart, but coagulated in the vessels.[2021] Dr. Reitz, a writer in Henke’s Journal, met with two cases of death from the same cause in hatters. They had incautiously exposed themselves too much to the fumes, which are disengaged during the preparation of nitrate of mercury for the operation of felting, and which are well known to be nitric oxide gas converted into nitrous acid vapour by contact with the air. Two men died of inflammation of the lungs excited in that manner; and a third, a boy of fourteen, after sleeping all night in an apartment where the mixture was effervescing, was attacked in the morning with yellowness of the skin, giddiness, and colic, which ended fatally in six days.[2022]

Of Poisoning with Chlorine.—The experiments of Nysten and Hébréart with chlorine, and its well-known irritating effects when inhaled in the minutest quantities, show that it will produce inflammation of the lungs and air-passages. The following is the only instance of poisoning with it in man which has come under my notice. A young man, after breathing diluted chlorine as an experiment, was instantly seized with violent irritation in the epiglottis, windpipe, and bronchial branches, cough, tightness, and sense of pressure in the chest, inability to swallow, great difficulty in breathing or articulating, discharge of mucus from the mouth and nostrils, severe sneezing, swelling of the face, and protrusion of the eyes. Ammonia was of no use; but singular relief was obtained from the inhalation of a little sulphuretted hydrogen, so that in an hour and a half he was tolerably well.[2023]

Although this gas is very irritating to an unaccustomed person, yet by the force of habit one may breathe with impunity an atmosphere much loaded with it. I have been told by a chemical manufacturer at Belfast, that his men can work in an atmosphere of chlorine, where he himself could not remain above a few minutes. The chief consequences of habitual exposure are acidity and other stomach complaints, which the men generally correct by taking chalk. He has likewise observed that they never become corpulent, and that corpulent men who become workmen are soon reduced to an ordinary size. It is not probable, however, that the trade is an unhealthy one; for several of this gentleman’s workmen have lived to an advanced age; one man, who died not long ago at the age of eighty, had been forty years in the manufactory; and I have seen in Mr. Tenant’s manufactory at Glasgow a healthy-looking man who had been also about forty years a workman there. It is an interesting fact, that during the epidemic fever which raged over Ireland from 1816 to 1819, the people at the manufactory at Belfast were exempt from it.

Of Poisoning with Ammonia.—For an account of the effects of ammonia, which, when in the state of gas, acts violently as an irritant on the mouth, windpipe, and lungs, the reader is referred to the chapter on ammonia and its salts in page 193. It appears to form one of the gases disengaged from the soil of necessaries, as will be noticed presently, and excites inflammation in the eyes of workmen who are incautiously exposed to it.[2024]

Of Poisoning with Hydrochloric Acid Gas.—I have not met with any account of the effects of hydrochloric acid gas on man. But no doubt can be entertained that it will likewise act as a violent and pure irritant.

It is exceedingly hurtful to vegetable life. In the course of some experiments performed in 1827 by Dr. Turner and myself on the effects of various gases on plants, we found that a tenth of a cubic inch diluted with 20,000 times its volume of air, so as to be quite imperceptible to the nostrils, shrivelled and killed all the leaves of various plants, which were exposed to it for twenty-four hours.[2025] These experiments were repeated in 1832 by Messrs. Rogerson, apparently in ignorance of them. Their results are on the whole the same; and the slighter effect obtained by them from minute proportions of the gas was evidently owing to the small size of their glass-jars not allowing them to use a sufficient quantity of it.[2026] They farther found that proportions of hydrochloric acid gas, amounting to a twentieth of the air, kill small animals in half an hour with symptoms of obstructed respiration. Their experiments with less proportions are not precise, yet warrant the inference that even a thousandth part of the gas will probably prove fatal in no long time.[2027]

Of Poisoning with Hydrosulphuric Acid Gas.—The narcotic gases are of much greater importance than the irritants, on account of the singularity of their effects, and the greater frequency of accidents with them. This group includes hydrosulphuric acid, carburetted-hydrogen, carbonic acid, carbonic oxide, nitrous oxide, cyanogen, and oxygen.

Hydrosulphuric acid gas is probably the most deleterious of all the gases. According to Thenard and Dupuytren, air containing only an 800th of it will kill small birds in a few seconds; and a 290th is sufficient to kill a dog; which, however, will sustain so much as a 400th.[2028] Chaussier previously found, that a horse was killed by breathing atmospheric air which contained a 250th of hydrosulphuric acid gas; and that it acts with energy on animals, whether it be inhaled, or injected into the stomach, anus, or cellular tissue, or even simply applied to the skin. Nine quarts of the gas injected into the anus of a horse killed it in one minute; and a rabbit, whose skin alone was exposed to it, died in ten minutes.[2029] Ulterior inquiries by MM. Parent-Duchâtelet and Gaultier de Claubry,—scarcely so precise however as those of their predecessors,—appear to lead to the conclusion, that its energy is in some circumstances not so great. While superintending the clearing out of some of the choked drains of Paris, they found that the workmen suffered no harm, though they habitually breathed an atmosphere containing from 25 to 80 ten-thousandths of hydrosulphuric acid gas, and on some occasions even so much as one per cent.; nay, on one occasion Gaultier remained several minutes without injury, collecting air for chemical analysis in an atmosphere, which proved to be loaded with three per cent. of the gas.[2030] None of these researches point out the precise manner of death. Dr. Percy of Nottingham informs me he found in 1839, that dogs, which breathed air, containing this gas, quickly died in convulsions like those caused by hydrocyanic acid; that in some instances the heart’s action was observed to have ceased, when the body was opened immediately after death; but that in general it either continued to beat for some time, or could be made to do so when its state of congestion was relieved by withdrawing a little blood.

Dr. Turner and I found that hydrosulphuric acid gas is very injurious to vegetables, and that it acts differently from muriatic acid gas, as it appeared to exhaust the vitality of plants and to cause in them a state analogous to narcotic poisoning in animals. Four cubic inches and a half, diluted with eighty volumes of air, caused drooping of the leaves of a mignonette plant in twenty-four hours; and the plant, though then removed into the open air, continued to droop till it bent over altogether and died.[2031]

The best description of the effects of this gas on man has been given by M. Hallé,[2032] in his account of the nature and effects of the exhalations from the pits of the Parisian necessaries; which exhalations appear, from the experiments of Thenard and Dupuytren, to be mixtures chiefly of ammonia and sulphuretted-hydrogen. The symptoms, in cases where the vapours are breathed in a state of concentration, are sudden weakness and all the signs of ordinary asphyxia. The individual becomes suddenly weak and insensible; falls down; and either expires immediately, or, if he is fortunate enough to be quickly extricated, he may revive in no long time, the belly remaining tense and full for an hour or upwards, and recovery being preceded by vomiting and hawking of bloody froth.[2033] When the noxious emanations are less concentrated, several affections have been noticed, which may be reduced to two varieties, the one consisting of pure coma, the other of coma and tetanic convulsions. In the comatose form, the workman seems to fall gently asleep while at work, is roused with difficulty, and has no recollection afterwards of what passed before the accident. The convulsive form is sometimes preceded by noisy and restless delirium, sometimes by sudden faintness, heaving or pain in the stomach, and pains in the arms, and almost always by difficult breathing, from weakness in the muscles of the chest. Insensibility, and a state resembling asphyxia rapidly succeed, during which the pupil is fixed and dilated, the mouth filled with white or bloody froth, the skin cold, and the pulse feeble and irregular. At last convulsive efforts to breathe ensue; these are followed by general tetanic spasms of the trunk and extremities; and if the case is to prove fatal, which it may not do for two hours, a state of calm and total insensibility precedes death for a short interval.[2034] When the exposure has been too slight to cause serious mischief, the individual is affected with sickness, colic, imperfectly defined pains in the chest, and lethargy.[2035]

The appearances in the bodies of persons killed by these emanations are fluidity and blackness of the blood, a dark tint of all the internal vascular organs, annihilation of the contractility of the muscles, more or less redness of the bronchial tubes, and secretion of brown mucus there as well as in the nostrils, gorging of the lungs, an odour throughout the whole viscera like that of decayed fish, and a tendency to early putrefaction.[2036] Chaussier in his experiments also remarked in animals, that when a plate of silver or bit of white lead was thrust under the skin it was blackened.[2037] Dr. Percy could not detect the gas in the brain of animals killed by inhaling it.

These extraordinary accidents may be occasioned not only by exposure to the vapours from the fosses, but likewise by the incautious inhalation of the vapours proceeding from the bodies of persons who have been asphyxiated there. Sickness, colic, and pains in the chest, are often caused in the latter mode; and Hallé has even given an instance of the most violent form of the convulsive affection having originated in the same manner.[2038]

In order that the reader may comprehend the exact cause of these accidents,—as it is not easy for an Englishman to comprehend how suffocation may arise from the fumes of a privy,—it may be necessary to explain, that in Paris the pipe of the privy terminates under ground in a pit, which is usually contained in a small covered vault, or is at the bottom of a small square tower open at the roof of the house; and that the pit is often several feet long, wide and deep. Here the filth is sometimes allowed to accumulate for a great length of time, till the pit is full; and it is in the process of clearing it out that the workmen are liable to suffer. Hallé has given an interesting narrative of an attempt made to empty one of these pits in presence of the Duc. de Rochefoucault, the Abbé Tessier, himself, and other members of the Academy of Sciences, who were appointed by the French government to examine into the merits of a pretended discovery for destroying the noxious vapours. The pit chosen was ten feet and a half long, six wide, and at least seven deep; and repeated attempts had been previously made without success to empty it. For some time the process went on prosperously; when at last one of the workmen dropped his bucket into the pit. A ladder being procured, he immediately proceeded to descend, and would not wait to be tied with ropes. “But hardly,” says Hallé, “had he descended a few steps of the ladder, when he tumbled down without a cry, and was overwhelmed in the ordure below, without making the slightest effort to save himself. It was at first thought he had slipped his foot, and another workman promptly offered to descend for him. This man was secured with ropes in case of accident. But scarcely had he descended far enough to have his whole person in the pit except his head, when he uttered a suppressed cry, made a violent effort with his chest, slipped from the ladder, and ceased to move or breathe. His head hung down on his breast, the pulse was gone; and his complete state of asphyxia was the affair of a moment. Another workman, descending with the same precautions, fainted away in like manner, but was so promptly withdrawn that the asphyxia was not complete, and he soon revived. At last a stout young man, secured in the same way as the rest, also went down a few steps. Finding himself seized like his companions, he re-ascended to recover himself for a moment; and still not discouraged, he resolved to go down again, and descended backwards, keeping his face uppermost, so that he was able to search for his companion with a hook and withdraw the body.” It was impossible to go on with the operation of clearing out; and the pit was shut up again. The first workman never showed any sign of life; the second recovered after discharging much bloody froth; all the persons in the vault were more or less affected; and a gentleman who, in trying to resuscitate the dead workman, incautiously breathed the exhalations from his mouth, was immediately and violently seized with the convulsive form of the affection.[2039]

The same kind of accident has been observed at Paris in the vaults of cemeteries, owing to the same cause,—the disengagement of hydrosulphuric acid and hydrosulphate of ammonia during putrefaction. A remarkable instance is related by Guérard.[2040] Analogous accidents have happened in this country in clearing out drains.

In none of the French investigations on this singular subject has any allusion been made to the question, whether the health sustains any injury from long-continued exposure to the gas in very minute proportion. It is probably injurious however. At one time, while in the practice of not using any precautions against inhaling the gas in chemical researches, I used to remark that daily exposure to it in minute quantity caused in a few weeks an extraordinary lassitude, languor of the pulse, and defective appetite. Strohmeyer in the like circumstances was liable to severe headache. Mr. Taylor says that the workmen in the Thames Tunnel suffered severely for some time from a similar exposure. Many of them became affected with giddiness, sickness, general debility and emaciation, then with a low fever attended with delirium, and in the course of a few months several died. No cause could be discovered for their illness except the frequent escape of sulphuretted-hydrogen from the roof. The affection only disappeared, when the communication from bank to bank was completed, so that the tunnel could be thoroughly ventilated.[2041]

The presence of hydrosulphuric acid in all such emanations is best proved by exposing to them a bit of filtering paper moistened with a solution of lead. The smell alone must not be relied on, as putrescent animal matter exhales an odour like that of hydrosulphuric acid, though none be present. Workmen ought to be aware that hydrosulphuric acid may be quickly fatal where lights burn with undiminished brilliancy; and that in places where it is apt to accumulate, the degree of purity of the air may vary so much in the course of working, as to be wholesome only a few minutes before, as well as a few minutes after a fatal accident.[2042]

In the present place, some notice may be taken of an extraordinary accident, which happened in 1831 near London. Great doubts may be entertained whether hydrosulphuric acid was the cause of it; and while these exist, it is not possible to arrange it under a proper head. It is too important, however, in relation to Medical Jurisprudence, to be omitted in this work; and I take the opportunity of mentioning it here, as the accident was ascribed to hydrosulphuric acid by those who witnessed it.

In August, 1831, twenty-two boys living at a boarding-school at Clapham were seized in the course of three or four hours with alarming symptoms of violent irritation in the stomach and bowels, subsultus of the muscles of the arms, and excessive prostration of strength. Another had been similarly attacked three days before. This child died in twenty-five, and one of the others in twenty-three hours. On examination after death, the Peyerian glands of the intestines were found in the former case enlarged, and as it were tuberculated; in the other there were also ulcers of the mucous coat of the small intestines, and softening of that coat in the colon. A suspicion of accidental poisoning having naturally arisen, the various utensils and articles of food used by the family were examined but without success. And the only circumstance which appeared to explain the accident was, that two days before the first child took ill, a foul cess-pool had been opened, and the materials diffused over a garden adjoining to the children’s play-ground. This was considered a sufficient cause of the disease by Dr. Spurgin and Messrs. Angus and Saunders of Clapham, as well as by Drs. Latham and Chambers, and Mr. Pearson of London, who personally examined the whole particulars.[2043] Their explanation may be the only rational account that can be given of the matter. But as no detail of their chemical inquiries was ever published, their opinion cannot be received with confidence by the medical jurist and the physician; since it is not supported, so far as I am aware by any previous account of the effects of hydrosulphuric acid gas.

Of Poisoning with Carburetted Hydrogen.—Of the several species of carburetted hydrogen gas it is probable that all are more or less narcotic; but they are much inferior in energy to sulphuretted hydrogen.

Sir H. Davy found that when he breathed a mixture of two parts of air and three of carburetted hydrogen, procured from the decomposition of water by red-hot charcoal, he was attacked with giddiness, headache, and transient weakness of the limbs. When he breathed it pure, the first inspiration caused a sense of numbness in the muscles of the chest; the second caused an overpowering sense of oppression in the breast, and insensibility to external objects; during the third he seemed sinking into annihilation, and the mouthpiece dropped out of his hand. On becoming again sensible, which happened in less than a minute, he continued for some time to suffer from a feeling of impending suffocation, extreme exhaustion, and great feebleness of the pulse. Throughout the rest of the day he was affected with weakness, giddiness and rending headache.[2044] These experiments show that the gas is deleterious. Yet Nysten found it inert when injected into the veins, and what is more to the point, colliers breathe the air of coal mines without apparent injury when strongly impregnated with it.

The mixed gases of coal-gas or oil-gas appear likewise to be inert when considerably diluted; for gas-men breathe with impunity an atmosphere considerably loaded with them; and in the course of some researches on the illuminating power and best mode of burning these gases, Dr. Turner and myself daily, for two months, breathed air strongly impregnated with them, but never remarked any unpleasant effect whatever.

It would seem, however, from several accidents in France and England, that when the impregnation is carried a certain length, poisonous effects may ensue; and that the symptoms then induced are purely narcotic. The first case, which occurred at Paris in 1830, has been related by M. Devergie. In consequence of a leak in the service-pipe which supplied a warehouse, five individuals who slept in the house were attacked during the night with stupor; and if one of them had not been awakened by the smell and alarmed the rest, it is probable that all would have perished. As it was, one man was found completely comatose and occasionally convulsed, with froth issuing from the mouth, occasional vomiting, stertorous respiration, and dilated pupils. Some temporary amendment was procured by blood-letting, but the breathing continued laborious, and he expired about nine hours after the party went to bed, and six hours after the alarm was given. On dissection the vessels of the brain were found much gorged, the blood in the heart and great vessels firmly coagulated, one of the lungs congested, and its bronchial tube blocked up by a kidney bean. The immediate cause of death in this case is therefore doubtful.[2045] A similar set of cases happened at Leeds in 1838. An old woman and her grand-daughter were found dead in bed one morning at nine o’clock, ten hours and a half after they had been seen alive and well. The air of the apartment was loaded with coal-gas from a leak in a street-pipe ten feet from the bedroom. One body was cold and stiff when found, and the other became rigid very soon. The attitude and expression were calm, the integuments pale, the cerebral membranes natural, the brain itself turgid, and its ventricles distended, in the case of the girl, with an ounce and a half of serosity, the lungs congested, the alimentary mucous membrane red, and the blood every where fluid, and unusually florid, even in the right side of the heart.[2046] Another accident of the same kind, which proved fatal to five individuals, occurred at Strasbourg in 1841. Four were found dead, another survived twenty-four hours after the accident was discovered, and a sixth recovered. It appears from the statement of this person, that the first symptoms were headache and giddiness, then nausea and vomiting, afterwards confusion of ideas, and at length insensibility. General prostration, partial palsy, coma, and convulsions were the leading symptoms after the accident was observed. In the four people found dead the most remarkable appearances were cerebral congestion, redness of the bronchial membrane, accumulation of bloody, frothy mucus in the air tubes, scarlet redness of the lungs, coagulation and darkness of the blood. In the person who was found alive, but did not recover, there was no cerebral congestion, gorging of the air tubes, or redness of the lungs. Professor Tourdes, who reports these cases, ascertained that air containing a fiftieth of coal-gas kills rabbits in twelve or fourteen minutes, and that even a thirtieth proves fatal, though slowly. The gas which caused the accident, and which was prepared from a mixture of water and slate coal, consisted of 22·5 per cent. light carburetted hydrogen, 6·0 bicarburetted hydrogen, 21·9 carbonic oxide, 31 hydrogen, 14 azote, and 4·6 carbonic acid; and by experiment the author found that the most energetic of these gases as a poison is the carbonic oxide, and that the action of the two carburetted-hydrogens is quite feeble.[2047] It is somewhat remarkable that no such accident has ever happened in Edinburgh, where nevertheless coal-gas is more used for purposes of illumination in private houses than in any other city. The fine quality of the gas,—for it contains a mere trace of carbonic acid, and probably less than four per cent. of carbonic oxide,—may be the reason why accidents are not occasioned by it. It is a singular fact, however, that the powerful odour of the gas, when it accidentally escapes in the night-time, generally awakes very soon those who are exposed to inhale it.

Of Poisoning with Carbonic Acid Gas.—Carbonic acid gas is the most important of the deleterious gases; for it is the daily source of fatal accidents. It is extricated in great quantity from burning fuel; it is given out abundantly in the calcining of lime; it is disengaged in a state of considerable purity in brew-houses by the fermentation of beer; it is often met with in mines and caverns, particularly in coal-pits and draw-wells; it may collect in apartments where fuel is burnt without a proper outlet for the vitiated air, or where persons are crowded too much for the capacity of the room. Hence many have been killed by descending incautiously into draw-wells, by falling into beer-vats, and by sleeping before the traps of lime-kilns, or in apartments without vents and heated by choffers. Instances have even occurred of the same accident from sleeping in greenhouses during the night, when plants exhale much carbonic acid; and some dreadful cases have occurred of suffocation from confinement in small crowded rooms.

Physiologists, as already remarked, are not quite agreed as to the action of carbonic acid gas,—whether it is a positive poison, or simply an asphyxiating gas. But in my opinion reasons enough exist for believing that it is positively and energetically poisonous. This is perhaps shown by its effects being much more rapidly produced, and much more slowly and imperfectly removed, than asphyxia from immersion in hydrogen or azote.[2048] Thus immersion for twenty-five seconds in an atmosphere of carbonic acid gas has been found sufficient to kill an animal outright; and fifteen seconds will kill a small bird.[2049] But it is more unequivocally established by the three following facts:

In the first place, if, instead of the nitrogen contained in atmospheric air, carbonic acid gas be mixed with oxygen in the same proportion, animals cannot breathe this atmosphere for two minutes without being seized with symptoms of poisoning.[2050] Even a much less proportion has the same effect. Five per cent. in the air will affect small birds in two minutes, and kill them in half an hour.[2051] Persons have become apoplectic in an atmosphere of carbonic acid gas, which to those who entered it appeared at first quite respirable.[2052]

Secondly, Professor Rolando of Turin having found that the land tortoise sustained little injury when the great air-tube of one lung was tied,—he contrived to make it breathe carbonic acid gas with one lung, while atmospheric air was inhaled by the other; and he remarked that death took place in a few hours.[2053]

Thirdly, the symptoms caused by inhaling the gas may be also produced by applying it to the inner membrane of the stomach or to the skin. On the one hand aërated water has been known to cause giddiness or even intoxication when drunk too freely at first;[2054] and the sparkling wines probably owe their rapid intoxicating power to the carbonic acid they contain. And, on the other hand, M. Collard de Martigny has found that, if the human body be enclosed in an atmosphere of the gas, due precautions being taken to preserve the free access of common air to the lungs, the usual symptoms of poisoning with carbonic acid are produced, such as weight in the head, obscurity of sight, pain in the temples, ringing in the ears, giddiness, and an undefinable feeling of terror; and that if the same experiment be made on animals and continued long enough, death will be the consequence.[2055]

When a man attempts to inhale pure carbonic acid gas, for example by putting the face over the edge of a beer-vat, or the nose into a jar containing chalk and weak muriatic acid, the nostrils and throat are irritated so strongly, that the glottis closes and inspiration becomes impossible. Sir H. Davy in making this experiment, farther remarked, that the gas causes an acid taste in the mouth and throat, and a sense of burning in the uvula.[2056] I have remarked the same effects from very pure gas disengaged by tartaric acid from carbonate of soda. Hence, when a person is immersed in the gas nearly or perfectly pure, as in a beer-vat, or old well, he dies at once of suffocation.

The effects are very different when the gas is considerably diluted; for the symptoms then resemble apoplexy. As they differ somewhat according to the source from which the gas is derived, and the admixtures consequently breathed along with it, it will be necessary to notice separately the effects of the pure gas diluted with air,—of the emanations from burning charcoal, tallow, and coal,—and finally of air vitiated by the breath.

1. M. Chomel of Paris has related a case of poisoning with the gas diluted with air, in the person of a labourer, who was suddenly immersed in it at the bottom of a well, and remained there three-quarters of an hour. He was first affected with violent and irregular convulsions of the whole body and perfect insensibility, afterwards with fits of spasm like tetanus; and during the second day, when these symptoms had gone off, he continued to be affected with dumbness.[2057]—It is worthy of particular remark that, contrary to general belief, these effects may be produced in situations where the air is not sufficiently impure to extinguish lights. Thus M. Collard de Martigny relates the case of a servant, who, on entering a cellar where grape-juice was fermenting, became suddenly giddy, and, under a vague impression of terror, fled from the place, dropping her candle on the floor and shutting the door behind her. She fell down insensible outside the door, and those who went to her assistance found on opening the door that the light continued to burn.[2058]—Mr. Taylor indeed has since ascertained that a candle will burn in air, which contains ten, or even twelve per cent. of carbonic acid,[2059]—a proportion more than sufficient to cause poisoning in no long time. It is also important to observe, that, contrary to what would be expected from the statements of Sir H. Davy and other experimentalists on the effects of the pure gas, it will often happen that no odour or taste is perceived. M. Bonami, in an account of an accident which happened at Nantes to two workmen who descended an old well, says that the first while descending uttered a piercing cry and fell down; and that as soon as his comrade, who tried to rescue him, was lowered ten or twelve feet, he felt as if he was about to be suffocated for want of breath, but perceived no strong or disagreeable smell.[2060] It should be remembered therefore by workmen, that there may be danger in descending pits where none is indicated by the sense of smell, or by the extinguishing of a light.

2. The fumes of burning charcoal have been long known to be deleterious. The early symptoms caused by them have been little noticed; for, as this variety of poisoning generally occurs during sleep, the patient is seldom seen till the symptoms are fully formed. In an attempt at self-destruction described in a French journal, the first effects were slight oppression, then violent palpitation, next confusion of ideas, and at last insensibility.[2061] Tightness in the temples, and an undefinable sense of alarm have also been remarked;[2062] and others have, on the contrary, experienced a pleasing sensation that seduced them to remain on the fatal spot.[2063] The best account of the incipient symptoms has been given by Mr. Coathupe of Wraxhall, in an account of an experiment he made with Joyce’s stove,—a preposterous invention, the fuel of which was supposed by the inventor to burn without contaminating the air, although it was neither more nor less than prepared charcoal. Having closed every aperture in a room of the capacity of eighty cubic yards, Mr. Coathupe kindled the stove and watched the results. In four hours he had slight giddiness, in five hours and a half intense giddiness, the desire to vomit without the power, excessive prostration and incapability of muscular effort, a frequent full throbbing pulse, a sense of distention of the cerebral arteries, agonizing headache, chiefly in the hindhead, but no sense of suffocation. At this time he experienced great difficulty in opening the window and removing the stove; and in seven hours, when his wife entered the room, he was unable to tell what was the matter, although quite conscious of all that was passing. He then slowly recovered.[2064] A similar account has also been given by Mr. Chapman of Tooting of the effects of this notorious stove. A young gentleman, after being only one hour in a chamber heated by it, felt first slight giddiness and headache, and afterwards violent pain in the head and tightness round the forehead and temples; the pupils became excessively dilated and nearly insensible; there was constant ringing in the ears, a feeble frequent pulse, paleness of the features and lividity of the lips and hands, coldness of the extremities, laborious irregular breathing, and extreme prostration. A temporary relief, obtained by stimulants, was succeeded by violence; which, however, was subdued by blood-letting; and he recovered.[2065] A set of cases, 70 in number, similar to the last two, but milder, occurred in January, 1836, in the church of Downham in Norfolk, which was heated by two of these stoves.[2066]

The following abstract of a case by Dr. Babington will convey an accurate idea of the advanced symptoms. The waiter of a tavern and a little boy, on going to bed, left a choffer of charcoal burning beside it; and next morning were found insensible. The boy died immediately after they were discovered. The waiter had stertorous breathing, livid lips, flushing of the face, and a full, strong pulse; for which affections he was bled to ten ounces. When Dr. Babington first saw him, however, the pulse had become feeble, the breathing imperfect, and the limbs cold; the muscles were powerless but twitched with slight convulsions, the sensibility gone, the face pale, the eyelids closed, the eyes prominent and rolling, the tongue swollen and the jaw locked upon it, and there was a great flow of saliva from the mouth. The employment of galvanism at this time caused an evident amendment in every symptom. But it was soon abandoned; because each time it was applied, the excitement was rapidly followed by corresponding depression. Cold water was then dashed upon him, ammonia rubbed on his chest, and oxygen thrown into the lungs; through which means a warm perspiration was brought out, and his state rapidly improved. He was nearly lost, however, during the subsequent night by hemorrhage from the divided vein; but next day he was so well that he could even speak a little. For two days afterwards the left side of the face was paralyzed, and his mental faculties were somewhat disordered.[2067]—In such cases as this the stupor is generally very deep. There is a case in a French Journal of a girl, who, after remaining some time in a small close chamber heated by a charcoal choffer, fell down insensible, remained in that state for three hours, and found, on recovering from her lethargy, that the choffer had fallen, and burnt the skin and subjacent fat of the thighs to a cinder.[2068]

Occasionally the stage of stupor is followed, as in some other varieties of narcotic poisoning, by a stage of delirium, at times of the furious kind, or by a state resembling somnambulism.[2069] It does not follow that recovery is certain because coma has thus given place to delirium,—an alteration, which in most varieties of narcotic poisoning is considered a sure sign of recovery. Collard de Martigny has related a case which eventually proved fatal, notwithstanding this sign of improvement.[2070]

The narcotism induced by breathing charcoal fumes often lasts a considerable length of time,—much longer indeed than the effects of other narcotic poisons. This will appear sufficiently from the case described by Dr. Babington. One of the people, mentioned at the commencement of this chapter as having been suffocated at Gerolzhofen, lingered five days in a state of coma before he expired.

Commonly in cases of recovery, there is found to have been no consciousness of any thing going on around, or recollection of what passed subsequently to the first impressions of poisoning. The reverse, however, occurred in Mr. Coathupe’s experiment; and a similar instance has been published, where the individual, though apparently insensible, knew when the room was first entered by strangers, and heard them call him by name and bid him put out his tongue, and stretch forth his arm,—without, however, his having the power to answer, or in any way to express the consciousness of understanding them.[2071]

Poisoning with charcoal vapour has become a subject of great importance in French medical jurisprudence, partly on account of the frequency with which it is resorted to for the purpose of committing suicide, and partly because repeated attempts have been made to conceal murder by arranging matters so as to present the appearances of suicide. M. Devergie says, that in the years 1834 and 1835 no fewer than 360 cases of poisoning with charcoal-vapour occurred in Paris, of which nearly four-fifths proved fatal; and he has given the particulars of two attempts to conceal murder under the appearance of death from this cause.[2072]

The subject has therefore been carefully examined by various authors, but by none so successfully as by M. Devergie; of whose important researches the following is a brief analysis.

In stating the various sources whence charcoal-vapour may become incidentally the cause of death, he dwells particularly on the risk of its admission from adjoining vents, even in other houses from that where the accidents happen,—because there may be currents in the apartment which occasion back-draught. Three remarkable cases of this kind, very obscure in their origin, have been related by M. d’Arcet.[2073]

The very discrepant effects of the poison on different individuals, simultaneously and to appearance alike exposed to it, have usually been explained by reference to the great density of the gas, which consequently accumulates near the floor. Some, however, have doubted the fact that the gas is unequally diffused. Mr. Taylor in particular says he ascertained by analysis, that air collected above and below a choffer of burning charcoal was equally contaminated, that what was collected a foot above its level contained 4·65 per cent., and that another portion taken the same distance below it contained 4·5 of carbonic acid.[2074] M. Devergie has discovered the source of these discrepant opinions. He has found,[2075] that, notwithstanding the high density of carbonic acid gas, the currents caused by the heat, disengaged when charcoal is burnt in a room, without an issue for the products of combustion, produce an equable mixture of gases at all elevations in the apartment, provided the air be examined while still warm, and not long after the charcoal has burnt out; but that, at a later period, such as twelve hours, the carbonic acid partly separates and sinks, so that, while the air at the top contains only a 78th, that near the floor contains four times as much, or a 19th of carbonic acid gas.

Disputes have also arisen as to the precise nature of the emanations from burning charcoal,—some believing that carbonic acid is alone discharged in such quantity as to prove injurious, and is singly sufficient to account for the effects which have been observed,—while others maintain that carbonic oxide, carburetted-hydrogen, or some peculiar pyrogenous vapour, may be also formed, and prove the real cause of the active properties of the vapour. According to the researches of Orfila, charcoal in a state of vivid ignition emits carbonic acid only, a hundred parts of the consumed air having been ascertained by him to be composed of 42 azote, 46 common air, and 12 carbonic acid. But when the combustion is low, a hundred parts consist of 52 azote, 20 common air, 14 carbonic acid, and 14 carburetted-hydrogen; so that not only is the air more thoroughly consumed; but likewise an additional poisonous gas is brought into action.[2076] The difference thus indicated has been supposed to account for what is often observed in countries where charcoal choffers are much in use for warming close apartments,—namely, that the practice is attended with most danger when the combustion is low, and that it is unsafe to close the doors of an apartment till the fuel is in a state of vivid ignition. M. Guérard again maintains, that when the supply of air is incomplete and combustion low, carbonic oxide gas is formed in considerable quantity; and that this gas, confessedly a much more powerful narcotic than carbonic acid, is probably the cause of many cases of poisoning with charcoal fumes.[2077] M. Devergie doubts the exactness of Orfila’s experiments on this head, but gives no new analysis. He observes that charcoal-vapour gives the air of a room a peculiar odour and bluish misty appearance, the latter of which slowly diminishes, and in twelve hours disappears; and that possibly there may be both a little carbonic oxide and carburetted-hydrogen in the air. But nevertheless he is of opinion that the carbonic acid alone is adequate to occasion all the effects observed in man or animals.[2078] Professor Hünefeld is of a different opinion, and has supplied the most satisfactory explanation of the important fact, that charcoal fumes are most noxious when the fuel has been just kindled and burns low; for he ascertained that at first it gives out a pyrogenous acid, which occasions headache and tendency to sickness, and which is not a product of combustion at the moment, but exists ready formed; and that when charcoal is at a full red heat, this noxious substance is no longer given off.[2079] Mr. Coathupe also thinks the cause of poisoning by charcoal fumes is an unknown pyrogenous body, and not carbonic acid gas.[2080]—This department of inquiry is obviously susceptible of more precise information. But meanwhile, whatever may be the probability that, besides carbonic acid, some other gases, or some peculiar pyrogenous body, may occasionally exist in charcoal fumes, and increase their poisonous property, little doubt can exist that the carbonic acid is singly sufficient to account for all the leading phenomena.

M. Devergie has been led to the opinion that air, in which a fourth part of its oxygen has been converted into carbonic acid, and which therefore contains five per cent. of that gas, is amply enough impregnated to occasion death.[2081] This corresponds with the observations of M. Ollivier, who found that three per cent. was as much as could be breathed with impunity even for a moderate length of time.[2082] Less, however, will suffice to prove injurious or even fatal, if the air be breathed long. Mr. Coathupe inferred from a rough estimate, that in the dangerous experiment he made upon himself, the carbonic acid, if uniformly diffused in the apartment, which was probably the case, amounted to only two per cent.; but his data were inadequate.[2083]

Proceeding from the fact that five per cent. of carbonic acid is sufficient to cause death, Devergie points out what quantity of charcoal is required to form that proportion,—a question of no small moment in respect to charges of murder, concealed under the semblance of suicide by suffocation with charcoal fumes. And he shows, that a French bushel, or decalitre, weighing 3000 grammes, is sufficient for a close apartment of 1275 cubic mètres, that is 6·6 pounds avoirdupois for a space of 1666 English cubic yards, provided the gas be uniformly diffused.[2084] The quantity of charcoal burnt in a given case may be arrived at pretty nearly from the weight of ashes left, which is estimated in round numbers at a twenty-fifth by himself,[2085] and at a twentieth by Ollivier.[2086]

It is important to remark that complete closure of an apartment is by no means essential for the action of carbonic acid, whether disengaged within it or introduced from without. For poisoning has occurred, even where a window was partially open.[2087]

3. It is probable that in some circumstances a very small quantity of the mixed gases proceeding from the slow combustion of tallow and other oily substances will produce dangerous symptoms. Dr. Blackadder remarked in the course of his experiments on flame, that the vapour into which oil is resolved, previous to its forming flame round the wick, excites in minute quantities intense headache.[2088] The emanations from the burning snuff of a candle, which are probably of the same nature, seem to be very poisonous. An instance indeed has been recorded in which they proved fatal. A party of iron-smiths, who were carousing on a festival day at Leipzig, amused themselves with plaguing a boy, who was asleep in a corner of the room, by holding under his nose the smoke of a candle just extinguished. At first he was roused a little each time. But when the amusement had been continued for half an hour he began to breathe laboriously, was then attacked with incessant epileptic convulsions, and died on the third day.[2089]—The effects of such emanations are probably owing to empyreumatic volatile oil, which will be presently seen to be an active poison.

4. The vapours from burning coal are the most noxious of all kinds of emanations from fuel, and cause peculiar symptoms. But they are less apt to lead to accidents than the vapour of charcoal, as they are much more irritating to the lungs. This effect depends on the sulphurous acid gas which is mingled with the carbonic acid.

Sulphurous acid gas is exceedingly deleterious to vegetable life, being hardly inferior in that respect to hydrochloric acid. Dr. Turner and I found that a fifth of a cubic inch diluted with ten thousand times its volume of air destroyed all the leaves of various plants in forty-eight hours.[2090] I am not acquainted with any experiments on animals or observations on man regarding the effects of the pure gas. But it will without a doubt prove a powerful irritant.

Some of the peculiarities in the cases now to be mentioned were possibly owing to the admixture of sulphuric acid gas with the carbonic, both being inhaled in a diluted state. The cases are described by Mr. Braid, at the time surgeon at Leadhills. In March, 1817, several of the miners there were violently affected, and some killed, in consequence, it was supposed, of the smoke of one of the steam-engines having escaped into the way-gates, and contaminated the air in the workings. Four men who attempted to force their way through this air into the workings below were unable to advance beyond, and seem to have died immediately. The rest attempted to descend two hours after, but were suddenly stopped by the contaminated air. As soon as they reached it, although their lights burnt tolerably well, they felt difficulty in breathing, and were then seized with violent pain and beating in the head, giddiness and ringing in the ears, followed by vomiting, palpitation and anxiety, weakness of the limbs and pains above the knees, and finally with loss of recollection. Some of them made their escape, but others remained till the air was so far purified that their companions could descend to their aid. When Mr. Braid first saw them, some were running about frantic and furious, striking all who came in their way,—some ran off terrified whenever any one approached them,—some were singing,—some praying,—others lying listless and insensible. Many of them retched and vomited. In some the pulse was quick, in others slow, in many irregular, and in all feeble. All who could describe their complaints had violent headache, some of them tenesmus, and a few diarrhœa. In a few days all recovered except the first four and three others who had descended to the deeper parts of the mine.[2091]—Another accident of the same nature, and followed by the same phenomena, happened more lately at Leadhills.[2092] Similar accidents have been also witnessed by Mr. Bald, civil engineer, among the coal-miners who work in the neighbourhood of a burning mine belonging to the Devon Company. It is worthy of remark, that the men sometimes worked for a considerable length of time before they were taken ill. Such being the case, it will be readily conceived that the burning of the lights was not a test of the wholesomeness of the air. Here, as at Leadhills and in other instances already mentioned, the lights continued to burn where the men were poisoned.[2093]

5. Somewhat analogous to the symptoms now described are the effects of the gradual contamination of air in a confined apartment. Every one must have read of the horrible death of the Englishmen who were locked up all night in a close dungeon in Fort William at Calcutta. One hundred and forty-six individuals were imprisoned in a room twenty feet square, with only one small window; and before next morning all but 23 died under the most dreadful of tortures,—that of slowly increasing suffocation. They seem to have been affected nearly in the same way as the workmen at Leadhills.[2094] A similar accident happened in London in 1742. The keeper of the round-house of St. Martin’s, crammed 28 people into an apartment six feet square and not quite six feet high; and four were suffocated.[2095]

The morbid appearances left on the body after poisoning with carbonic acid gas have been chiefly observed in persons killed by charcoal vapour. According to Portal the vessels of the brain are congested, and the ventricles contain serum; the lungs are distended, as if emphysematous; the heart and great veins are gorged with black fluid blood; the eyes are generally glistening and prominent, the face red, and the tongue protruded and black.[2096]—Gorging of the cerebral vessels seems to be very common. Yet sometimes it is inconsiderable, as in two cases related by Dr. Bright, where, except in the sinuses and in the greater veins of the ventricles and substance of the brain, no particular gorging or vascularity seems to have been met with,—the external membranes in particular having been very little injected.[2097] This, however, is certainly a rare occurrence. Serous effusion in the ventricles and under the arachnoid membrane is very general, yet not invariable.—Dr. Schenck, medical inspector of Siegen, in reporting two cases of death caused by the vapours of burning wood, notices paleness of the countenance as a singular accompaniment of cerebral congestion; and calls the attention of medical jurists to the extreme calmness of the features as a general character of this variety of poisoning.[2098] Although the same appearance has also been noticed by others,[2099] the countenance nevertheless is often livid. But whether livid or pale, it is always composed.—It appears from an account in Pyl’s Essays of several cases of suffocation from the fumes of burning wood, that besides the appearances mentioned by Portal, there is usually great livor of the back, frothiness as well as fluidity of the blood, and more or less gorging of the lungs with blood.[2100]—A common appearance where the poisonous emanation has been charcoal vapour, is a lining of dark, or sometimes actually black dust on the mucous membranes of the air passages, thickest near the external opening of the nostrils, and disappearing towards the glottis. There are obvious reasons why this appearance cannot always be expected to occur; but when present, it may be in doubtful circumstances a very important article of evidence.[2101] In Wildberg’s collection of cases there is a report on two people who were suffocated in bed, in consequence of the servant having neglected to open the flue-trap when she kindled the stove in the bed-chamber; and in each of them Wildberg found all the appearances now quoted from Portal and Pyl. The tongue was black and swelled.[2102]—Mertzdorff has related a case of death from the same cause, in which, together with the preceding appearances, an effusion of blood was found between the arachnoid and pia mater over the whole surface of both hemispheres.[2103] In one of Dr. Bright’s cases there was a small ecchymosis in the cortical substance on the outer side of the anterior lobe, and not extending into the medullary matter. Fallot mentions an instance of suffocation from charcoal vapour, where a little coagulated blood was found between the layers of the arachnoid membrane of the cerebellum in the region of the left occipital hollow.[2104] Three instances of extravasation are enumerated in a list of German cases analysed by Dr. Bird.[2105] Such appearances might be expected more frequently, considering the manifest tendency of this kind of poisoning to cause congestion in the head.—The blood is generally described as being liquid and very dark. But M. Ollivier has lately called attention to the fact, that the blood both before and after death is not unusually more florid in the veins than natural.[2106] In a case mentioned by M. Rayer globules of an oily-looking matter were found swimming on the surface of the blood and urine.[2107] This is a solitary observation.—The body usually remains flaccid, and the customary stage of rigidity is imperfect. In some instances, however, as in those related by Dr. Schenck, the stage of rigidity is passed through in the usual manner. It is not uncommon to find vomited matter lying beside the body, a circumstance which may naturally mislead the unpractised. This is represented by Professor Wagner of Berlin to have occurred uniformly in his experience;[2108] and it is also mentioned in many of the cases reported by others;[2109] but it is not invariable.—A red appearance in the stomach and intestines has been noticed in many cases,[2110] and often ascribed to inflammation; but it is probably nothing more than the result of the venous congestion, which pervades most of the membranous surfaces of the body.

The least variable appearances according to Dr. Bird are general lividity, protrusion of the tongue, a calm expression and attitude, cerebral congestion, and serous effusion. This author’s paper in the Medical Gazette, 1838–39, i., or in Guy’s Hospital Reports, iv., enters very fully into the appearances after death, and may be consulted with advantage for further details.

The treatment of poisoning with carbonic acid consists chiefly in the occasional employment of the cold affusion, and in moderate blood-letting either from the arm or from the head. In a case which happened at Paris, where a lady tried to make away with herself by breathing charcoal fumes, and was found in a state of almost hopeless insensibility, various remedies were tried unsuccessfully, till cupping from the nape of the neck was resorted to; and she then rapidly recovered.[2111] Another instance where blood-letting was also singularly successful deserves particular mention; because for three hours the patient remained without pulsation in any artery, and without the slightest perceptible respiration. At first neither by cupping nor by venesection could any blood be obtained; and it was only after the long interval just mentioned, and constant artificial inflation of the lungs, that the blood at length trickled slowly from the arm. The pulse and breathing were after this soon re-established; but it was not till eight hours later that sensibility returned.[2112]

Of Poisoning with Carbonic Oxide Gas.—Carbonic oxide gas, according to Nysten, has not any effect on man when injected into the pleura; but when thrown slowly into the veins, it gives the arterial blood a brownish tint, and induces for a short time a state resembling intoxication.[2113] The quantity injected into the veins was probably too small to produce the full effect, or it was discharged in passing through the lungs; for this gas certainly appears to be very deleterious when breathed by man, or the lower animals. M. Leblanc found by experiment that a sparrow was killed almost immediately in air containing only a twentieth of it, and that so little even as a hundredth part proved fatal in two minutes.[2114]

A set of interesting but hazardous experiments were made with it in 1814 by the assistants of Mr. Higgins of Dublin. One gentleman, after inhaling it two or three times, was seized with giddiness, tremors, and an approach to insensibility, succeeded by languor, weakness, and headache of some hours’ duration. The other had almost paid dearly for his curiosity. Having previously exhausted his lungs, he inhaled the pure gas three or four times, upon which he was suddenly deprived of sense and motion, fell down supine, and continued for half an hour insensible, apparently lifeless, and with the pulse nearly extinct. Various means were tried for rousing him, without success; till at last oxygen gas was blown into the lungs. Animation then returned rapidly: but he was affected for the rest of the day with convulsive agitation of the body, stupor, violent headache, and quick irregular pulse; and after his senses were quite restored, he suffered from giddiness, blindness, nausea, alternate heats and chills, and then feverish, broken, but irresistible sleep.[2115] A French aëronaut, who used for his balloon a mixture of carbonic oxide and hydrogen, obtained by decomposing water with red-hot charcoal, lately suffered from similar symptoms in a milder degree, in consequence of the gas being disengaged upon him from the safety-valve of his balloon.[2116]

Of Poisoning with Nitrous Oxide Gas.—The nitrous oxide or intoxicating gas is the last of the narcotic gases to be noticed. Nysten found, that, when slowly injected in large quantity into the veins of animals, it only caused slight staggering.[2117] Frequent observation, however, has shown that it is by no means so inert when breathed by man. Sir H. Davy, who first had the courage to inhale it, observed that it excited giddiness, a delightful sense of thrilling in the chest and limbs, acuteness of hearing, brilliancy of all surrounding objects, and an unconquerable propensity to brisk muscular exertion. These feelings were of short duration, but were generally succeeded by alertness of body and mind, never by the exhaustion, depression, and nausea, which follow the stage of excitement brought on by spirits or opium.[2118] Although many have since experienced the same enticing effects, yet they are by no means uniform. For others have been suddenly seized with great weakness, tendency to faint, loss of voice, and sometimes convulsions; and two of Thenard’s assistants, on making the experiment, fainted away, and remained some seconds motionless and insensible.[2119] It is a remarkable circumstance in the operation of this gas, that, unlike other stimulants, it does not lose its virtues under the influence of habit. Neither does the habitual use of it lead to any ill consequence. Sir H. Davy, in the course of his researches, which were continued above two months, breathed it occasionally three or four times a day for a week together, at other periods four or five times a week only; yet at the end his health was good, his mind clear, his digestion perfect, and his strength only a little impaired.[2120]

Nitrous oxide gas is one of the few gases that are not injurious to vegetables. Dr. Turner and I found that seventy-two cubic inches, diluted with six times their volume of air, had no effect on a mignionette plant in forty-eight hours.[2121]

Of Poisoning with Cyanogen Gas.—Cyanogen gas has been proved by the experiments of M. Coullon to be an active poison to all animals,—the guinea-pig, sparrow, leech, frog, wood-louse, fly, crab; and the symptoms induced were coma, and more rarely convulsions.[2122] These results are confirmed by the later experiments of Hünefeld, who found that it produces in the rabbit anxious breathing, slight convulsions, staring of the eyes, dilated pupils, coma, and death in five or six minutes.[2123] Buchner likewise found that small birds, held for a few seconds over the mouth of a jar containing cyanogen, died very speedily; and on one occasion remarked, while preparing the gas, that the fore-finger, which was exposed to the bubbles as they escaped, became suddenly benumbed, and that this effect was attended with a singular feeling of pressure and contraction in the joints of the thumb and elbow.[2124] It would undoubtedly be most dangerous to breathe this gas, except much diluted, and in very small quantity.

Of all narcotic gases it is the most noxious to vegetables. Dr. Turner and I found that a third of a cubic inch, diluted with 1700 times its volume of air, caused the leaves of a mignionette plant to droop in twenty-four hours. As usual with the effects of narcotic gases on vegetables, the drooping went on after the plant was removed into the open air; and in a short time it was completely killed.[2125]

Of Poisoning with Oxygen Gas.—Of all the narcotic gases, none is more singular in its effects than oxygen. When breathed in a state of purity by animals, they live much longer than in the same volume of atmospheric air. But if the experiment be kept up for a sufficient length of time, symptoms of narcotic poisoning begin to manifest themselves. For an hour no inconvenience seems to be felt; but the breathing and pulse then become accelerated; a state of debility next ensues; at length insensibility gradually comes on, with glazing of the eyes, slow respiration and gasping; coma is in the end completely formed; and death ensues in the course of six, ten, or twelve hours. If the animals are removed into the air before the insensibility is considerable, they quickly recover. When the body is examined immediately after death, the heart is seen beating strongly, but the diaphragm motionless; the whole blood in the veins as well as the arteries is of a bright scarlet colour; some of the membranous surfaces, such as the pulmonary pleura, have the same tint, and the blood coagulates with remarkable rapidity. The gas in which an animal has died rekindles a blown out taper. These experiments, which physiology owes to the researches of Mr. Broughton,[2126] furnish a solitary example of death from stoppage of the respiration, although the heart continues to pulsate, and the lungs to transmit florid blood. Death is probably owing to hyper-arterialization of the blood.

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XXXII. CLASS THIRD. OF NARCOTICO-ACRID POISONS GENERALLY

The third class of poisons, the narcotico-acrids, includes those which possess a double action, the one local and irritating like that of the irritants, the other remote, and consisting of an impression on the nervous system.

Sometimes they cause narcotism; which is generally of a comatose nature, often attended with delirium; but in one very singular group there is neither insensibility nor delirium, but merely violent tetanic spasms.

At other times they excite inflammation where they are applied. This effect, however, is by no means constant. For Orfila justly observes, that under the name of narcotico-acrids several poisons are usually described which seldom excite inflammation. Those which inflame the tissues where they are applied rarely occasion death in this manner. Some of them may produce very violent local symptoms; but they generally prove fatal through their operation on the nervous system.

For the most part, their narcotic and irritant effects appear incompatible. That is, when they act narcotically, the body is insensible to the local irritation; and when they irritate, the dose is not large enough to act narcotically. In large doses, therefore, they act chiefly as narcotics, in small doses as irritants. Sometimes, however, the narcotic symptoms are preceded or followed by symptoms of irritation; and more rarely both exist simultaneously.

Most, if not all, of them, to whatever part of the body they are applied, act remotely by entering the blood-vessels; but it has not been settled whether they operate by being carried with the blood to the part on which they act, or by producing on the inner membrane of the vessels a peculiar impression, which is conveyed along the nerves. Some of them produce direct and obvious effects where they are applied. Thus monkshood induces a peculiar numbness and tingling of the part with which it is placed in contact. The organs on which they act remotely are the brain and spine, and sometimes the heart also.

The appearances in the dead body are, for the most part, inconsiderable; more or less inflammation in the stomach or intestines, and congestion in the brain; but even these are not constant.

As a distinct class, they differ little from some poisons of the previous classes. Several of the metallic irritants, and a few vegetable acrids are, properly speaking, narcotico-acrids: they excite either narcotism or irritation, according to circumstances. But still, the poisons about to be considered form a good natural order when contrasted with these irritants. For the irritants which possess a double action are nevertheless characterized by the symptoms of inflammation being at least their most prominent effects; while the most prominent feature in the effects of the poisons now to be considered is injury of the nervous system. It is more difficult to draw the line of separation between the present class and the pure narcotics; for many narcotico-acrids rarely cause any symptom but those of narcotism.

The narcotico-acrids are all derived from the vegetable kingdom. Many of them owe their power to an alkaloid, consisting of oxygen, hydrogen, carbon, and azote.

The characters which distinguish the symptoms and morbid appearances of the narcotico-acrids from those of natural disease, do not require special mention; for almost all the remarks made in the introduction to the class of narcotics are applicable to the present class also. A few of the characters, however, which have been laid down, do not apply so well to the narcotico-acrids as to the narcotics. In particular, it appears that what was said on the short duration of the effects of the narcotics does not apply so well to the present class of poisons; some of which, in a single dose, continue to cause symptoms even of narcotism for two or three days. But the rule, that they seldom prove fatal if the case lasts above twelve hours, is still applicable,—at all events they rarely prove fatal after that interval by their narcotic action. The poisonous fungi, however, have proved fatal as narcotics so late as thirty-six hours, or even three days, after they were taken; and perhaps digitalis has proved fatal narcotically at the remote period of three weeks. But such cases are extremely rare.

Some narcotico-acids, such as the different species of strychnos, are quite peculiar in their effects; so that their symptoms may be distinguished at once from natural disease.

Orfila divides the narcotico-acrids into six groups, and this arrangement will be followed in the present work; but they are not all very well distinguished from one another.

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XXXIII. OF POISONING WITH NIGHTSHADE, THORN-APPLE, AND TOBACCO

The first group of the narcotico-acrids comprehends these whose principal symptom in the early stage of their effects is delirium. All the plants of the group belong to the natural order Solanaceæ, and Linnæus’s class Pentandria Monogynia. Those which have been particularly examined are deadly nightshade, thorn-apple, and tobacco.

Of Poisoning with Deadly Nightshade.

The deadly nightshade, or Atropa belladonna, is allied in physiological and botanical characters to the hyoscyamus and solanum formerly mentioned; and by the older writers, indeed, was confounded with the latter. It is a native of Britain, growing in shady places, particularly on the edge of woods. The berries, which ripen in September, have a jet-black colour. Their beauty has frequently tempted both children and adults to eat them, although they have a mawkish taste; and many have suffered severely. It is not the berry alone which is poisonous; the whole plant is so; and the root is probably the most active part.[2127] From one to four grains of the dried powder of the root will occasion dryness in the throat, giddiness, staggering, flushed face, dilated pupils, and sometimes even delirium.[2128] The juice of the leaves is very energetic, two grains of its extract being, when well prepared, a large enough dose to cause disagreeable symptoms in man. It is a very uncertain preparation, unless when procured by evaporation in vacuo; for some samples from the Parisian shops have been found by Orfila to be quite inert.

It contains a peculiar alkaloid, named atropia. In the belladonna Brandes obtained a volatile, oily-like, alkaloidal fluid, of a penetrating narcotic smell, and bitterish, acrid taste, which he supposed to be the active principle of the plant.[2129] The ulterior researches of Geiger and Hesse, however, as well as the simultaneous analysis of Mein, have proved that this fluid is not the pure alkaloid of belladonna, and that the real atropia is a solid substance, forming colourless, silky crystals, soluble in ether and alcohol, sparingly so in water, slightly bitter, liable to decomposition under contact with air and moisture, volatilizable, but with some decomposition, a little above 212°, and capable of forming definite crystallizable salts with acids.[2130] The aqueous solutions of its salts exhale during evaporation a narcotic vapour, which dilates the pupil, and causes sickness, giddiness, and headache.[2131]

The ordinary extract of belladonna in the dose of half an ounce will kill a dog in thirty hours when introduced into the stomach. Half that quantity applied to a wound will kill it in twenty-four hours. And forty grains injected into the jugular vein prove even more quickly fatal. Convulsions are rarely produced, but only a state like intoxication.[2132]

The oleaginous atropia of Brandes in a dose of two or three drops kill small birds instantaneously like concentrated hydrocyanic acid; in less doses it occasions staggering, gasping, and in a few minutes death amidst convulsions; and the dead body presents throughout the internal organs great venous turgescence and even extravasation of blood, but more especially excessive congestion within the head.[2133] The pure crystalline atropia of Mein, when dissolved in water and greatly diluted, causes extreme and protracted dilatation of the pupils.

Symptoms in Man.—On man the effects of belladonna are much more remarkable. In small doses, whatever be the kind or surface to which it is applied,—such as the skin round the eye, or the surface of a wound, or the inner membrane of the stomach,—it causes dilatation of the pupil. This effect may be excited without any constitutional derangement. When the extract is rubbed on the skin round the eye, or a solution of it dropped upon the eyeball, vision is not impaired; but when it is taken internally so as to affect the pupils, the sight is commonly much obscured. The effects of large or poisonous doses have been frequently witnessed in consequence of children and adults being tempted to eat the berries by their fine colour and bright lustre. From the cases that have been published the leading symptoms appear in the first instance to be dryness in the throat, then delirium with dilated pupils, and afterwards coma. Convulsions are rare, and, when present, slight.

The dryness of the throat is not a constant symptom. It is often, however, very distinct. It occurred, for example, in 150 soldiers who were poisoned near Dresden, as related by M. Gaultier de Claubry,[2134] and in six soldiers whose cases have been described by Mr. Brumwell.[2135] The former had not only dryness of the throat, but likewise difficulty in swallowing.

The delirium is generally extravagant, and also most commonly of the pleasing kind, sometimes accompanied with immoderate uncontrollable laughter, sometimes with constant talking, but occasionally with complete loss of voice, as in the cases of the 150 soldiers. At other times the state of mind resembles somnambulism, as in the instance of a tailor who was poisoned with a belladonna injection, and who for fifteen hours, though speechless and insensible to external objects, went through all the customary operations of his trade with great vivacity, and moved his lips as if in conversation.[2136] Sometimes frantic delirium is almost the only symptom of consequence throughout the whole duration of the poisoning. Thus a gentleman at Perigueux in France, who took by mistake a mixture containing a drachm and a half of extract, was attacked in half an hour with delirium, which soon became furious, and continued till next day, when it gradually left him.[2137] In others the delirium is attended with a singular and total loss of consciousness, but without coma, as in the following case which occurred not long ago at St. Omer. A young man having taken by mistake an infusion of two drachms of dried leaves, was seized in an hour with great dryness of the mouth and throat, afterwards slight delirium, loss of consciousness, and dilatation of the pupil, next with retention of urine, convulsive twitches of the face and extremities, and incessant tendency to walk up and down. In three hours, after the action of an emetic and a clyster, he lay down, but still in a state of total unconsciousness and muttering delirium. Blood-letting being at last resorted to as a remedy, he speedily recovered his senses, and eventually got well, after suffering for some time from headache, fatigue, and much debility.[2138]

The pupil is not only dilated in all cases, but likewise for the most part insensible;[2139] and, as in the soldiers at Dresden, the eyeball is sometimes red and prominent. The vision also, as in these soldiers, is generally obscure; sometimes it is lost for a time;[2140] and so completely that even the brightest light cannot be distinguished.[2141]

The sopor or lethargy, which follows the delirium, occasionally does not supervene for a considerable interval. In a case related by Munnik it did not begin till twelve hours after the poison was taken.[2142] Sometimes, as in the same case, the delirium returns when the stupor goes off. A patient of my colleague Dr. Simpson, after using a belladonna suppository consisting of two grains of extract, was attacked with dryness of the throat and delirium, followed soon by drowsiness and stupor; and in five or six hours more, as the stupor wore off, the delirium returned, prompting to constant movements as if she was busy with her toilette and various other ordinary occupations. Sometimes the relation of the delirium to the coma is reversed, as in a case related by Mr. Clayton, where sopor came on first, and delirium ensued in six hours. The dose in this instance was forty grains of the extract.[2143] Frequently the stupor is not distinct at any stage.—Even the delirium is not always formed rapidly. A man whose case is described by Sir John Hill did not become giddy for two hours after eating the berries, and the delirium did not appear till five hours later.[2144] In Mr. Brumwell’s cases, the delirium was not particularly noticed till the morning after the berries were taken.

Convulsions, it has been already stated, are rare. In the case from the 24th volume of Sedillot’s Journal, the muscles of the face were somewhat convulsed: there is also at times more or less locked-jaw,[2145] or subsultus tendinum;[2146] and occasionally much abrupt agitation of the extremities.[2147] But well-marked convulsions do not appear to be ever present.

The effects now detailed are by no means so quickly dissipated as those of opium. Almost every person who has taken a considerable dose has been ill for a day at least. The case from Sedillot’s Journal lasted three days, delirium having continued twelve hours, the succeeding stupor for nearly two days, and the departure of the stupor being attended with a return of delirium for some hours longer. One of Mr. Brumwell’s patients, too, was delirious for three days; and Plenck has noticed several instances where the delirium was equally tedious.[2148] Sage has related a case in which the individual was comatose for thirty hours.[2149] Blindness is also a very obstinate symptom, which sometimes remains after the affection of the mind has disappeared. This happened in Plenck’s cases. In two children whose cases have been described in a late French journal, the eyes were insensible to the brightest light for three days.[2150] In general, the dilated state of the pupils continues long after the other symptoms have departed. It further appears from an official narrative in Rust’s Journal, that dilated pupil is not the only symptom which may thus continue, but that various nervous affections, such as giddiness, disordered vision, and tremors, may prevail even for three or four weeks.[2151]

Hitherto little or no mention has been made of symptoms of irritation from this poison. They are in fact uncommon, and seldom violent. In the cases related by Gaultier de Claubry and by Mr. Brumwell, dryness and soreness of the throat and difficult deglutition were remarked, and appear not unusual. These symptoms were especially noticed by Buchner, who by way of curiosity took half a drachm of seeds digested in beer. The sense of dryness and constriction of the throat were such as to prevent him swallowing even the saliva.[2152] Sage’s patient passed blood by stool; and after the symptoms of narcotic poisoning ceased, he had aphthous inflammation in the throat, and swallowing was so difficult as for some time to excite convulsive struggles. Aphthæ in the throat and swelling of the belly also succeeded the delirium in Munnik’s case. Mr. Wibmer alludes to the case of a man who, besides difficult deglutition at the beginning, had violent strangury towards the close.[2153] An instance of violent strangury with suppression of urine and bloody micturition is also related by M. Jolly. In the early stage, the patient had redness of the throat and burning along the whole alimentary canal, combined with the customary delirium and loss of consciousness. The symptoms were caused by forty-six grains of the extract given by mistake instead of jalap.[2154] Nausea and efforts to vomit are not infrequent at the commencement.

If the accident be taken in time, poisoning with belladonna is rarely fatal; for, as the state first induced is delirium, not sopor, suspicion is soon excited, and emetics may be made to act before a sufficient quantity of the poison has been absorbed to prove fatal. Hence few fatal instances have occurred in recent times. Mr. Wilmer, however, has mentioned two fatal cases occurring in children, and terminating within twenty-four hours.[2155] M. Boucher, a writer in the old French Journal of Medicine, has referred to several cases of the same nature;[2156] Gmelin has described the particulars of a good example;[2157] and many others have been succinctly quoted by Wibmer, chiefly from the older authors.[2158]

Cases of poisoning with this plant have occurred in man through other channels besides the stomach. Allusion has already been made to the instance of a tailor who was poisoned by an injection. A small quantity will sometimes suffice when administered in that way. A woman, whose case is mentioned in Rust’s Journal, was attacked with wild delirium, flushed face and glistening eyes, in consequence of receiving, during labour, a clyster, that contained six grains of the common extract;[2159] and Dr. Simpson’s patient, who was severely affected, had only two grains.

Perhaps the berry is in some circumstances not very active. A French physician, M. Gigault of Pontcroix, says he has frequently had occasion to treat cases of poisoning with it, as accidents of the kind are extremely common in his neighbourhood; that he never knew it prove fatal; and that in one instance a young man took a pound of the berries before going to bed, and was not subjected to treatment till next morning, when he was found in a state of delirium, but speedily recovered after the free operation of emetics.[2160]

Morbid Appearances.—I have hitherto seen but one good account of the appearances after death from poisoning with belladonna. It is described by Gmelin. The subject was a shepherd who died comatose twelve hours after eating the berries. When the body was examined twelve hours after death, putrefaction had begun, so that the belly was swelled, the scrotum and penis distended with fetid serum, the skin covered with dark vesicles, and the brain soft. The blood-vessels of the head were gorged, and the blood every where fluid, and flowing profusely from the mouth, nose, and eyes.[2161] In the only other fatal case I have read, where the body was inspected, there appears to have been no unusual appearance at all.[2162]

As the husks and seeds of the berries are very indigestible, some of them will almost certainly be found in the stomach, as happened in the instance last quoted. It should likewise be remembered that the best possible evidence of the cause of the symptoms may be derived during life from the presence of the seeds, husks, or even entire berries, in the discharges. If vomiting has not been brought on at an early period, we may expect to find these remains both in the vomited matter and in the alvine evacuations. Mr. Wilmer mentions an instance in which the black husks appeared in the stools brought away by laxatives at least thirty hours after the poison was swallowed.[2163] One of Mr. Brumwell’s patients vomited the seeds towards the close of the third day.[2164] Several patients of M. Boucher vomited fragments of the fruit on the second day, and passed more by stool and injections on the third, although they had been treated with activity from the commencement.[2165]

While most of the cases of poisoning with belladonna have originated in accident, at the same time they have not been all of this description. Gmelin has quoted an instance of intentional and fatal poisoning by the juice of the berries being mixed with wine; and another singular case of poisoning with the decoction of the buds, given by an old woman for the purpose of committing theft during the stupor of the individual.[2166]

Other species of atropa are probably similar to belladonna in properties. Wibmer quotes a single instance of frantic delirium occurring among several shepherds, as well as their cattle, from eating the herb of the A. mandragora.[2167] This is well known to have been used anciently as a medicinal narcotic.

Of Poisoning with Thorn-Apple.

The thorn-apple, or Datura stramonium, is another plant of the same natural order, which it is proper to notice, because people have often been poisoned with it, and it has become a common ornament of our gardens. The cases of poisoning which have occurred in recent times in this country have been all accidental. But not long ago the thorn-apple appears to have been extensively used in Germany to cause loss of consciousness and lethargy, preparatory to the commission of various crimes.[2168] It was also proved to have been used lately in France for this purpose. Some thieves made a man insensible with wine in which stramonium seeds had been steeped, and robbed him of five hundred francs while in this state. For twenty-four hours the victim knew nothing of what became of him; he was met wandering in a wood, affected with delirium, unconsciousness, staring of the eyes, and oppression of the breathing; and for some time he was taken for a madman.[2169] In the Eastern Archipelago, according to Mr. Crawford, this is a common mode of committing theft and robbery.[2170]

It is chiefly the fruit and seeds that have hitherto been examined; but the whole plant is probably poisonous. Brandes discovered in it a volatile, oleaginous, alkaline substance, which he supposed to be its active principle.[2171] But, though his observations were confirmed by Bley,[2172] it now appears that the real principle is a colourless, crystalline alkaloidal substance, of an acrid taste like tobacco, which was discovered more lately by Geiger and Hesse; this is named daturine, or daturia.[2173]

The physiological effects of the extract have been determined by Orfila. He found that half an ounce killed a dog within twenty-four hours after being swallowed, that a quarter of an ounce applied to a wound killed another in six hours, and that thirty grains killed another when injected into the jugular vein. The symptoms were purely nervous, and not very prominent. Hence this poison, like the former, acts through the blood-vessels, and probably on the brain.[2174] Bley’s daturia proves quickly fatal to small animals in the dose of a few drops. The crystalline daturia of Geiger and Hesse kills a sparrow in the dose of an eighth of a grain, and occasions great and persistent dilatation of the pupil when applied to the eye.

Symptoms in Man.—The symptoms produced by a poisonous dose in man are variable. The leading features are great delirium, dilatation of the pupils, and stupor; but sometimes spasms occur, and occasionally palsy.

Dr. Fowler has related the case of a little girl who took a drachm and a half of the seeds. In less than two hours she was attacked with maniacal delirium, accompanied with spectral illusions; and she remained in this state most of the following night, but had some intervals of lethargic sleep. Next morning, after the operation of a laxative, she fell fast asleep, and after some hours she awoke quite well.[2175] In a case somewhat like this, related in Henke’s Journal, the child had general redness of the skin, swelling of the belly, locked jaw, tremors of the extremities, and an attitude and expression as if about to tumble into a pit. Recovery took place after the action of an emetic.[2176]

In two instances, one related by Vicat in his treatise on the poisonous plants of Switzerland,[2177] the other by Dr. Swaine[2178] in the Edin. Phys. and Lit. Essays, the leading symptoms were furious delirium and palsy of the whole extremities. In the instances of three children related by Alibert there were delirium, restlessness, constant incoherent talking, dancing and singing, with fever and flushed face.[2179] In another recorded by Dr. Young, there were some convulsions, and livid suffusion of the countenance.[2180] In an instance communicated to me by my colleague Dr. Traill, where eighteen or twenty grains of extract of stramonium were taken by mistake for sarsaparilla, the symptoms were dryness of the throat immediately afterwards, then giddiness, dilated pupils, flushed face, glancing of the eyes, and incoherence, so that he seemed to his friends to be intoxicated: and subsequently there was incessant unconnected talking, like that of demency. Emetics were given without effect, and little amendment was obtained from blood-letting, leeches on the temples, cold to the head, or purgatives. But after a glass of strong lemonade vomiting took place, the symptoms began to recede, in ten hours he recognized those around him, and next day he was pretty well. Kaauw Boerhaave has related with great minuteness the case of a girl who very nearly lost her life in consequence of a man having given her the powder in coffee with the view of seducing her. The symptoms were redness of the features, delirium, nymphomania, loss of speech; then fixing of the eyes, tremors, convulsions, and coma; afterwards tetanic spasm and slow respiration with the coma. She was with much difficulty roused for a time by the operation of emetics, and eventually got well after her lethargy had lasted nearly a day.[2181] In another related in Rust’s Magazin, and caused by a decoction of the fruit, which was mistaken for thistle-heads, the leading symptoms were spasmodic closing of the eyelids and jaws, spasms also of the back, complete coma, and excessive dilatation and insensibility of the pupil.[2182] This case, which seems to have been a very dangerous one, was rapidly cured by free blood-letting. Blood-letting, indeed, seems peculiarly called for in poisoning with thorn-apple, on account of the strong signs of determination of blood to the head.—Gmelin has quoted several fatal cases, one of which endured for six hours only;[2183] and Dr. Young says, that a child has been killed by a single apple.[2184] The most complete account yet published of the phenomena of poisoning with stramonium when fatal is given by Mr. Duffin of London. A child of his own, two years old, swallowed about 100 seeds without chewing them. Soon after she became fretful and like a person intoxicated; in the course of an hour efforts to vomit ensued, together with flushed face, dilated pupils, incoherent talking, and afterwards wild spectral illusions and furious delirium. In two hours and a half she lost her voice and the power of swallowing, evidently owing to spasms of the throat. Then croupy breathing and complete coma set in, with violent spasmodic agitation of the limbs, occasional tetanic convulsions, warm perspiration, and yet an imperceptible pulse. Subsequently the pulse became extremely rapid, the belly tympanitic, and the bladder paralyzed, but with frequent involuntary stools, probably owing to the administration of cathartics; and death took place in twenty-four hours. At an early period twenty seeds were discharged by an emetic: the stools contained eighty; and none were found in the alimentary canal after death. There was never any marked sign of congestion of blood in the head, except flushed face at the beginning.[2185] Dr. Droste of Osnaburg has related a fatal case occasioned by a decoction of 125 seeds given to remove colic. In fifteen minutes the patient became delirious, but soon fell apparently fast asleep, and died in seven hours without again awaking.[2186]

Dangerous effects may result from the application of the thorn-apple to the skin when deprived of the cuticle. An instance has been lately published of alarming narcotism from the application of the leaves to an extensive burn.[2187]

Morbid Appearances.—As to the morbid appearances, Droste found in his case redness of the cardiac end of the stomach, which contained two table-spoonfuls of a pulpy matter mixed with black and white grains, the remains of the teguments of the seeds; and there was also lividity of the back, lividity of the lungs, emptiness of the cavities of the heart, and gorging of the vessels of the brain. Haller says he once found general congestion of the brain and sinuses,[2188]—an appearance which may naturally be expected, considering the signs of strong determination of blood towards the head, which often prevail during life. In Mr. Duffin’s case, however, the brain was healthy, not congested; the stomach and intestines presented no morbid appearance; and the only unusual appearances observed were a slight blush over the pharynx, larynx, and upper third of the gullet, thickening and swelling of the rima glottidis, and a semi-coagulated state of the blood.

Of Poisoning with Tobacco.

A plant of the same natural order with the two former, tobacco, the Nicotiana tabacum of botanists, is familiarly known to be in certain circumstances a virulent poison. Every part of the plant possesses active properties. It has been used as a poison in this country for criminal purposes.

Vauquelin analyzed it some time ago, and procured an acrid volatile principle which he called nicotine.[2189] This substance, which was afterwards obtained in a purer state as a crystalline body by Hermbstädt, has been more recently ascertained by MM. Posselt and Reimarus to be nothing else than essential oil of tobacco, which is sold at ordinary temperatures; and they succeeded in procuring another principle which they consider the true nicotina. This is fluid at 29° F., volatile, extremely acrid, alkaline, and capable of forming crystallizable salts with some of the acids.[2190] Tobacco then appears to contain an acrid alkaline principle, and an essential oil to which the alkaloid adheres with great obstinacy. The relation of the empyreumatic oil of tobacco to these principles has not been accurately ascertained, though it probably contains one or other of them. It is well known to be an active poison, which produces convulsions, coma and death. Mr. Morries-Stirling found that its active part is removed from the oil by washing with weak acetic acid, as he also observed in the instance of similar oils obtained from various narcotic vegetables.[2191]

Process for detecting Tobacco in Organic mixtures.—In a medico-legal case which happened at Aberdeen in 1834, and of which some notice is taken at page 651, Dr. Ogston of that city successfully employed the following process for detecting tobacco in the contents of the stomach. The contents, consisting of a pulpy fluid, were acidulated with acetic acid, digested, and filtered; the liquid was treated with diacetate of lead, filtered again, freed of lead by hydrosulphuric acid, filtered a third time, treated with caustic potash, and then allowed to settle. The supernatant liquid, which had the taste of tobacco-juice, was separated and distilled to half its volume. The distilled liquor had a strong tobacco odour and taste, and some acridity, and gave a precipitate with infusion of galls. The residuum in the retort presented oily particles on its surface, and when heated in an open basin filled the apartment with a vapour which had a strong odour of tobacco smoke, and caused in several persons present a sense of acridity of the throat, watering of the eyes, and tendency to sneeze. Various additional experiments confirmatory of these results were also performed; and a simultaneous examination of tobacco-powder gave precisely the same indications. I am indebted to Dr. Ogston for these particulars and a detailed narrative of his investigation; which appears to supply a convenient and conclusive process for the detection of tobacco.—Perhaps the ordinary process for obtaining nicotina may also be employed with advantage. This consists in distilling the suspected substance with caustic potash, neutralizing the distilled liquor with sulphuric acid, concentrating the product to a thin syrup, exhausting this with etherized alcohol, evaporating off the solvent, and distilling the extract with strong solution of potash. Nicotina passes over, and may be recognized by its sensible and chemical qualities.

The effects of tobacco are somewhat different from those of belladonna and thorn-apple; but it is here arranged with them, as it belongs to the same natural family. Orfila remarked that 5½ drachms of common rappee, introduced into the stomach of a dog and secured by a ligature, caused nausea, giddiness, stupor, twitches in the muscles of the neck, and death in nine hours; and that two drachms and a quarter applied to a wound proved fatal in a single hour. Mr. Blake thinks tobacco has no direct action on the heart, even when admitted directly into the blood by the jugular vein;—that it acts primarily on the capillary circulation of the lungs, by obstructing which it prevents the blood from reaching the left cavities of the heart, and thus acts on that organ indirectly. For he observed, that laboured respiration always preceded any sign of depressed action of the heart, that forcible action of the heart often returned after its first cessation, and that its contractility continued after death.[2192] An infusion of ten grains caused laborious breathing in ten seconds, and in twenty seconds temporary arrestment of the heart’s action, which then returned, and was attended for a time with increased arterial pressure. Soon afterwards the animal recovered, without any convulsions or loss of sensibility. Two scruples had the same effect. But when three drachms were used, convulsions succeeded similar phenomena, and death ensued in two minutes, the heart continuing to act for some time after respiration had ceased, until at length it was stopped by the usual consequences of asphyxia.[2193] On the other hand, Sir B. Brodie found that the effects are very different, according to the form in which the poison is used. Thus four ounces of a strong infusion, when injected into the anus of a dog, killed it in ten minutes by paralyzing the heart; for after death the blood in the aortal cavities was arterial. But the empyreumatic essential oil does not act in that manner: it excites convulsions and coma, without affecting the heart. It may prove fatal in two minutes.[2194] Like other violent poisons, tobacco has no effect when applied directly to the brain or nerves.[2195] Two drops of the alkaloid, nicotina, injected into the jugular vein of a dog, begin to act in ten seconds, and will prove fatal in a minute and a half.[2196]

Symptoms in Man.—The effects observed in man are allied to those produced in dogs by the infusion. In a slight degree they are frequently witnessed in young men, while making their first efforts to acquire the absurd practice of smoking. The first symptoms are acceleration and strengthening of the pulse, with very transient excitement, then sudden giddiness, fainting and great sickness, accompanied with a weak, quivering pulse. These effects are for the most part transient and trifling, but not always. Some degree of somnolency is not uncommon. Dr. Marshall Hall has given an interesting account of a young man who smoked two pipes for his first debauch, and in consequence was seized with nausea, vomiting, and syncope, then stupor, stertorous breathing, general spasms and insensible pupils. Next day the tendency to faint continued, and in the evening the stupor, stertor and spasms returned; but from that time he recovered steadily.[2197] Gmelin has quoted two cases of death from excessive smoking,—caused in one by seventeen, in the other by eighteen pipes, smoked at a sitting.[2198] It is likewise mentioned by Lanzoni that an individual fell into a state of somnolency and died lethargic on the twelfth day in consequence of taking too much snuff;[2199] Dr. Cheyne says, “he is convinced apoplexy is one of the evils in the train of that disgusting practice;”[2200] and I have met with an instance where the excessive use of snuff, occasioned twice, at distant intervals, an attack resembling imperfect apoplexy, united with delirium. Such cases, however, must be admitted to be rare; and the practice of taking snuff is in general unattended with injury.

Serious consequences have resulted from the application of tobacco to the abraded skin. In the Ephemerides an account is given of three children who were seized with giddiness, vomiting, and fainting from the application of tobacco-leaves to the head for the cure of ring-worm.[2201] Dr. Merriman has also alluded to an instance of death in a child from the incautious employment of a strong decoction of tobacco as a lotion for ring-worm of the scalp.[2202] And in Leroux’s Journal there is an account of a man, who, after using a tobacco decoction for the cure of an eruptive disease, was seized with symptoms of poisoning, and died in three hours.[2203]

In recent times poisoning with tobacco has been often produced by the employment of too large doses in the way of injection. Richard has mentioned a case, not fatal, which arose from an infusion of five leaves in a choppin of water, used as an injection by a lady for costiveness. She was immediately seized with colic, giddiness, buzzing in the ears, headache, nausea, and then syncope of seven hours’ duration. During this period the breathing was difficult, the pulse very slow, the pupils dilated, the skin cold and moist, the urine suppressed, the efforts to vomit constant, and the belly depressed, contracted, and affected with constant borborygmus. She recovered under the use of emollient injections and fomentations.[2204] Dr. Grahl of Hamburg has related minutely a fatal case, which arose from an ounce of rather more, boiled for fifteen minutes in water, and administered by advice of a female quack. The individual, who laboured merely under dyspepsia and obstinate costiveness, was seized in two minutes with vomiting, violent convulsions, and stertorous breathing, and died in three-quarters of an hour.[2205] Another accident of the same kind is noticed in the Journal de Chimie Médicale, where the person became as it were intoxicated, and died immediately. Instead of an infusion of two drachms she had used a decoction of two ounces.[2206]—M. Tavignot describes the following remarkable case occasioned by a similar dose. An infusion prepared by mistake with two ounces and one drachm, instead of a drachm and a half, was used as an injection for a stout man affected with ascarides. In seven minutes he was seized with stupor, headache, paleness of the skin, pain in the belly, indistinct articulation, and slight convulsive tremors, at first confined to the arms, but afterwards general. Extreme prostration and slow laborious breathing soon ensued, and then coma, which ended fatally in eighteen minutes.[2207]—Even two drachms, however, or a drachm and a half, are by no means a safe dose. An anonymous writer in the Medical and Surgical Journal says a patient of his died in convulsions an hour or two after receiving a clyster composed of two drachms infused in eight ounces.[2208] Nay, in the Acta Helvetica there is an account by an anonymous writer of the case of a woman, who, after an injection made with one drachm only, was seized with pain in the belly, anxiety and faintings, proving fatal in a few hours.[2209] And a case, fatal in thirty-five minutes, which was occasioned by the same dose, occurred not long ago in Guy’s Hospital, London.[2210]

Tobacco is an equally deadly poison when swallowed in large quantity. M. Caillard has related the particulars of the case of a lunatic, who, having swallowed half an ounce of snuff during a lucid interval, was seized with vomiting, and afterwards with oppression, incoherence, cold sweats, a slow full pulse, and dilated pupils; but he slowly recovered.[2211] The French poet Santeuil was killed in this way by a practical joker at the Prince of Condé’s table. When the bottle had circulated rather freely, a boxful of Spanish snuff was emptied into a large glass of wine, and thus administered to the unlucky victim, who was in consequence “attacked with vomiting and fever, and expired in two days amidst the tortures of the damned.”[2212] The following important case has been communicated to me by Dr. Ogston of Aberdeen, who was employed in the judicial investigations connected with it. An elderly man, a pensioner, was seen to enter a brothel, while in perfect health; and in an hour he was carried out insensible and put down in a passage, where he was found by the police unable to speak or move. While carrying him to the watch-house hard by, the officers observed him attempt to vomit; but he was scarcely laid down before the fire, when he expired. It was ascertained, that he had drunk both rum and whisky in the brothel, and that something had been given him “to stupefy him or set him asleep.” On dissection the blood was found every where very fluid, and four ounces of serosity were collected from the lateral ventricles and base of the skull. But there was no other unusual appearance, except that the stomach contained about four ounces of a thick brownish pulp, in which were seen several pellets of a powder resembling snuff. In these contents Dr. Ogston could not detect any opium; but he detected tobacco by the process mentioned above. No doubt could exist that the man died of poisoning with tobacco; but as no evidence could be obtained to inculpate any one in particular of many individuals who were in the brothel with him, the case was not made the subject of trial.

Evidence is not wanting, therefore, to prove that this plant is a very active poison; yet every one knows that under the influence of habit it is used in immense quantities over the whole world as an article of luxury, without any bad effect having ever been clearly traced to it. Its poisonous qualities were known in Europe as soon as it was brought from America; and the belief that such properties could not fail to be attended, as in the case of spirits and opium, with evil consequences from its habitual use, led to much opposition on the part of various governments to its introduction. Soon after it was brought to England by Sir W. Raleigh, King James wrote a philippic against it, entitled “The Counter-blaste to Tobacco.” Some countries even prohibited it by severe edicts. Amurath the 4th in particular made the smoking of tobacco capital; several of the Popes excommunicated those who smoked in the church of St. Peter’s; in Russia it was punished with amputation of the nose; and in the Canton of Bern it ranked in the tables next to adultery, and even so lately as the middle of last century a particular court was held there for trying delinquents.[2213] Like every other persecuted novelty, however, smoking and snuff-taking passed from place to place with rapidity; and now there appear to be only two luxuries which yield to it in prevalence, spirituous liquors and tea.

The only accounts I have seen of the morbid appearances after poisoning with tobacco are contained in the cases of Dr. Grahl and Dr. Ogston. In the former there was great lividity of the back, paleness of the lips, flexibility of the joints (two days after death), diffuse redness of the omentum without gorging of vessels, similar redness with gorging of vessels both on the outer and inner coats of the intestines, in some parts of the mucous coat patches of extravasation, unusual emptiness of the vessels of the abdomen; while the stomach was natural, the lungs pale, the heart empty in all its cavities, and the brain natural. The appearances in Dr. Ogston’s case have been already stated.

Writers on the diseases of artisans have made many vague statements on the supposed baneful effects of the manufacture of snuff on the workmen.[2214] It is said they are liable to bronchitis, dysentery, ophthalmia, carbuncles and furuncles. At a meeting of the Royal Medical Society of Paris, however, before which a memoir to this purport was read, the facts were contradicted by reference to the state of the workmen at the Royal Snuff Manufactory of Gros-Caillou, where 1000 people are constantly employed without detriment to their health.[2215] This subject was afterwards investigated with care by MM. Parent-Duchatelet and D’Arcet, who inquired minutely into the state of the workmen employed at all the great tobacco-manufactories of France, comprising a population of above 4000 persons; and the results at which they arrived are,—that the workmen very easily become habituated to the atmosphere of the manufactory,—that they are not particularly subject either to special diseases, or to disease generally,—and that they live on an average quite as long as other tradesmen.[2216] These facts are derived from accurate statistical returns, showing the number of days each person was annually off work from sickness, the ages at which superannuated allowances were granted, the period of death, and the prevalent diseases.

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