Part 3 — MINERAL POISONS. (continued 3)

Yellow (protoxide) contains of lead 91·5 oxygen 8·5

Yellow (deutoxide) contains of lead 90·5 oxygen 9·5

Red (tritoxide) contains of lead 88· oxygen 12·

Brown (peroxide) contains of lead 80· oxygen 20·

Lead, in its metallic state, does not exert any action on the living system; but, when oxidized, or in the state of salt, its virulence is very considerable, producing a train of symptoms, so peculiar to itself, as to justify our placing its preparations in a separate class, under the title of astringent poisons, as explained at page 202.

Metallic lead, although per se inert, may occasion deleterious effects when introduced into the stomach, in consequence of its meeting with acids in the primæ viæ; from the same cause, liquids which are liable to become in any degree acidulous, if kept in leaden vessels, may be productive of much danger to those who drink them. Pure water, provided the air be excluded, does not appear to exert any sensible action upon this metal; but the combined influence of these agents converts the lead into a carbonate: a fact which is at once exemplified by the white line which is so constantly visible at the surface of the water preserved 338in leaden vessels. So well acquainted were the ancients with this fact, that we find frequent allusions in their works to the dangerous property of leaden utensils. Vitruvius^[348] published a very strong remonstrance against leaden pipes, when used for the purpose of conveying water; and Galen cautions us continually, not to employ water that has flowed through pipes of this metal; since he had observed that the sediment of such water, (υποσταθμη του τουιουτου υδατος) rendered such as swallowed it, δυσεντερικους, subject to disorders in the intestines.

Dr. Lambe, to whom we are indebted for an important work^[349] upon this subject, states, that there is a great diversity in the corrosive powers of different waters; in some places the use of leaden pumps has been in part discontinued, from the expense entailed upon the proprietors by the perpetual want of repair;^[350] and if any acidity be communicated to the water, from the accidental intrusion of decayed leaves or other vegetable matter, its power of dissolving this metal will be increased to a very dangerous extent. The noted colic of Amsterdam is said by Tronchin, who has written a history of the epidemic, to have been occasioned by leaves falling and putrefying in 339leaden cisterns, filled with rain water. Van Swieten^[351] has also related an instance of a whole family who were afflicted with colic from a similar cause; and Dr. Lambe^[352] entertains no doubt but that the very striking case recorded in the Medical Commentaries,^[353] proceeded more from some foulness in the cistern than from the solvent power of the water; in this instance, the officers of a packet vessel used water out of a leaden cistern; the men also drank the same water, except that the latter had been kept in wood; the consequence was, that all the officers were seized with colic, while the men remained healthy. Sir George Baker has furnished the following striking illustration of the subject. “The most remarkable case that now occurs to my memory, is that of Lord Ashburnham’s family, in Sussex; to which, spring water was supplied from a considerable distance in leaden pipes. In consequence, his lordship’s servants were every year tormented with colic, and some of them died. An eminent physician of Battle, who corresponded with me on the subject, sent up some gallons of that water, which were analysed by Dr. Higgins, who reported that the water had contained more than the common quantity of carbonic acid; and that he found in it lead in solution, which he attributed to the carbonic acid. In consequence of this representation, Lord Ashburnham substituted wooden for leaden pipes; and from that time his family have experienced no particular complaints in their bowels.”

But the most extensive and dangerous source of poisoning by lead, is the presence of this metal in various wines, and acescent drinks, and meats, and 340which may arise either from accident or design. A knowledge of the different avenues, through which this poison may gain admittance into the human body, is therefore of great importance to the forensic physician, and we shall accordingly proceed to the investigation of the subject.

That certain wines were occasionally liable to produce endemic colics, is a fact which has been long known; although the disease was universally ascribed to a mistaken origin, until the publication of the elaborate researches^[354] of Sir George Baker, into the cause of the Devonshire colic; which, like the same disease observed in other countries, was attributed to the acidity of the liquor so abundantly drunk^[355] in these districts. This celebrated physician, however, was early led to entertain doubts with respect to the truth of this doctrine: “when I consider,” says he, “that this colic of Devonshire is precisely the same disease as that which is the specific effect of all saturnine preparations, and that there is not the least analogy between the juice of apples and the poison of lead, it seems to me very improbable that two causes, bearing so little relation to one another, should make such similar impressions on the human body.” The investigation of the subject completely 341established the justness of these views; and no doubt remains, but that the endemic colic, which harrassed the cyder drinkers in Devonshire for some years, was the effect of saturnine impregnation, derived from the lead used in the construction of the apple mills and cyder presses; and in some cases, from the pernicious practice of introducing a leaden weight into the cask, or even racking the cyder into leaden cisterns, where the liquor fretted too much, and was thereby in danger of becoming acetous. Sir G. Baker also states that the custom of boiling the must in vessels capped with lead, affords another source of saturnine impregnation; and he informs us that, a few years ago, this very practice produced the Devonshire colic in the county of Kent. Some cyder, which had been made in a gentleman’s family, being thought too sour, was boiled with honey in a brewing vessel, capped with lead. All, who drank this liquor, were seized with this disease; some more, others less violently; one of the servants died very soon in convulsions: several others were cruelly tortured a long time. The master of the family, notwithstanding all the assistance which art could give him, never recovered his health; but died miserably, after having for nearly three years languished under a tedious and incurable malady. Dr. Lambe observes, that the saturnine colic is not endemial in Devonshire, or the other cyder countries, during the whole year, but is confined to those months when the liquor is still new, crude, and the fermentation incomplete. When the liquor becomes fine, the noxious matter in a great measure separates, and is carried to the bottom of the vessel, as the feculencies subside. Tartar is generated during the vinous fermentation, the acid of which, uniting with the lead, forms a salt, scarcely, if 342at all, soluble in water; and hence the purification which the liquor receives. But although this new salt is insoluble in water, it is otherwise in regard to vinegar; for this acid dissolves a small quantity, and forms a triple compound, an aceto-tartrate of lead;^[356] and since no cyder, or perhaps wine, is wholly destitute of vinegar, it necessarily follows that if the liquor has been once contaminated during the first stages of fermentation, it is impossible for it ever to become entirely pure, except by processes which would render it unfit for drinking.^[357] It has very lately been discovered, that Gallic acid and tannin are capable of combining with lead in solution, and of forming a perfectly insoluble substance, which falls to the bottom of the cask; hence all liquors which have been kept in oak casks, for a certain time, must be freed from lead. This explains a fact with respect to the effect of new rum in the West Indies, of some importance. This spirit, when newly distilled, is found to contain traces of lead, derived from the leaden rims of the coppers, and the leaden worm, used for its condensation; but, by keeping about twelve months in oaken casks, it loses its deleterious properties, and no longer exhibits any traces of this metal.^[358]

Another source, from which acescent liquids may contract saturnine impregnation, is afforded by the metallic glazing of earthenware^[359]; that for instance 343of the common cream coloured ware is composed of an oxide of lead,^[360] and is accordingly easily acted upon by vinegar, and saline compounds; jars and pots of this description ought therefore never to be used for preserving pickles, jellies of fruits, marmalade, and similar conserves. For the same reason, Sir George Baker protests against the custom of baking fruit tarts in such ware.^[361] Stone ware is glazed with muriate of soda, and is therefore not liable to such an objection.^[362]

344The custom which prevails in some parts of England of keeping milk in leaden vessels, is extremely improper; Dr. Darwin^[363] has illustrated this subject by the following case; “A delicate young girl, the daughter of a dairy farmer, who kept his milk in leaden cisterns, used to wipe off the cream from the edges of the lead, and frequently, as she was fond of cream, licked it from her finger. She was seized with the saturnine colic, and semi-paralytic wrists, and sunk from general debility.” We are informed by Mr. Parkes,^[364] that in Lancashire the dairies are furnished with milk-pans made of lead; and that when he expostulated with some individuals on the danger of this practice, he was told that leaden milk pans throw up the cream much better than vessels of any other kind.

There is, says Dr. Darwin, a bad custom in almost all families, and public houses, of washing out their wine bottles by putting a handful of shot corns into them, and by shaking them about forcibly to detach the super-tartrate of potass from their sides; that such a practice may occasionally give origin to serious consequences, will become evident by the relation of the following case.^[365] “A gentleman who had never in his life experienced a day’s illness, and who was constantly in the habit of drinking half a bottle of Madeira after his dinner, was taken ill three hours after dinner with a serious pain in the stomach and violent colic, which gradually yielded within twelve hours to the remedies prescribed by his medical attendant. The day following he drank the remainder of the same bottle of wine which was left the preceding 345day, and within two hours afterwards he was again seized with the most violent pains, head-ache, shiverings, and great pain over the whole body. His apothecary becoming suspicious that the wine he had drunk might be the cause of the disease, ordered the bottle, from which it had been decanted, to be brought to him, with a view that he might examine the dregs, if any were left. The bottle happening to slip out of the hand of the servant, disclosed a row of shot, wedged forcibly into the angular bent-up circumference of it. On examining the beads of shot, they crumbled into dust, the outer crust (defended by a coat of black lead with which the shot is glazed) being alone left unacted on, whilst the remainder of the metal was dissolved. The wine, therefore, had become contaminated with lead, and perhaps arsenic, for in order to form shot the former metal is alloyed with the latter.”^[366]

But we have, hitherto, only directed the reader’s attention to the different sources from which wine, and acescent liquors, may accidentally derive saturnine impregnation. We have now to state that such liquors have, in different ages and countries, been fraudulently adulterated with lead. It appears to have been early discovered, that wines which have become morbidly acescent may be corrected by the addition of lead; whence, in those countries where Rhenish, Moselle, and other similar wines are drunk, the saturnine colic has been endemic. The celebrated colic which raged in the province of Poitou, towards the end of the sixteenth, and in the beginning of the seventeenth century, was evidently the effect of such 346adulteration.^[367] We find that, in the year 1487, there was a Recessus Imperii promulgated at Rotenberg; and, in the year 1498, at Friberg; which was enacted, in the year 1500, at Tubingen; and, in the year 1508, at Frankfort; and, in the year 1577, in the same place. By which decrees it was made a capital crime to adulterate wines with litharge, or to use bismuth in the fumigation of them; it having been, at several periods, represented to the Emperors, that great mischief had accrued from such adulterations; and that they had been the cause of insuperable and mortal diseases. It should seem, that these laws were not carried into strict execution; and, indeed, that in the latter end of the seventeenth century, it was hardly known in Germany that such laws existed. In consequence of which, an epidemic colic arose, which was at length traced to the effects of lead in the wines.^[368] A representation of this fact having been made to the Duke of Wirtemberg, it was ordained a capital crime to mix litharge with 347wine, or even to sell it in the shops, by a decree, bearing date March 10, 1696. But, notwithstanding the severity of this law, we are informed by Zeller, that in the year 1705, the same dangerous experiments were repeated in the circle of Zwaabe, with a view to correct the acidity of the weaker wines. Bishop Watson^[369] informs us that, in the year 1750, the Farmers general in France being astonished at the great quantities de vin gaté which were brought into Paris, in order to be made into vinegar, redoubled their researches to find out the cause of the great increase in that article; for nearly thirty thousand hogsheads had been annually brought in for a few years preceding the year 1750, whereas the quantity annually brought in forty years before, did not exceed 1200 hogsheads. They discovered that several wine merchants, assuming the name of vinegar merchants, bought these sour wines, and afterwards, by means of litharge, rendered them potable, and sold them as genuine wines.^[370] Dr. Warren^[371] has related the cases of thirty-two persons in the Duke of Newcastle’s family, who were residing in Hanover in June, 1752, and were seized with the Colica Pictonum, after having used, as their common drink, a small white wine that has been adulterated with lead. Nor has the English vintner been less regardless of the health of his employer. In a popular work on wine making by Graham,^[372] which has gone through six editions, and may therefore be supposed to have done 348some mischief, we find under the article of vintner’s secrets, the following receipts.—

“To hinder wine from turning,

“Put a pound of melted lead, in fair water, into a cask, pretty warm, and stop it close.”

“To soften green wine,

“Put in a little vinegar, wherein litharge has been well steeped, and boil some honey to draw out the wax. Strain it through a cloth, and put a quart of it into a tierce: and this will mend it, in summer especially.”

We have already alluded to the presence of lead^[373] in the new rum of the West Indies, as the cause of the disease known in that country by the name of the dry belly-ache; it remains for us to state that the excise officers frequently avail themselves of the peculiar power of the sub-acetate of lead to precipitate colouring matter, in order to remove from seized Holland gin, the colour which it obtains by being long kept in the tubs in which it is smuggled over. A practice which it is said renders the gin liable to gripe.

According to the important experiments of Proust,^[374] it appears, that if lead be associated with tin, it will be incapable of furnishing to acids any saturnine impregnation. The following are the interesting conclusions at which this philosopher has arrived, viz.

“That the tinning, which contains even so large a proportion as an equal part of lead, cannot be dangerous; since it is sufficient that the lead should be 349combined with tin, in order to prevent it from being dissolved, either in lemon juice, or vinegar, the two acids most to be feared. The tin, being more oxidable than the lead, dissolves exclusively in these acids, and prevents the second from being attacked. The lead cannot appropriate to itself an atom of oxygen, but the tin would carry it off in an instant.”

Sugar of Lead—Saccharum Saturni—Cerussa Acetata—Plumbi Super-acetas.

This salt of lead, to whose presence the numerous accidental maladies above enumerated are to be chiefly attributed, occurs in commerce in the form of irregular masses resembling lumps of sugar, being an aggregation of acicular four-sided prisms terminated by dihedral summits; its taste is sweet and astringent. It is soluble in 25 parts of water, hot, or cold; when common spring water, however, is employed for such a purpose, a white precipitate occurs from the presence of a certain proportion of sulphates and carbonates.

When this salt is exposed to the action of heat, it undergoes aqueous fusion, then dries, and at length is decomposed, leaving a globule of metallic lead, mixed with the yellow protoxide, and an acid product of a fetid smell. This decomposition is similar to that which vegetable substances undergo when heated for some time. The quantity of metallic lead, thus obtained, will be more considerable if the salt has been previously mixed with charcoal, and particularly if it be submitted for a long time to the action of a powerful heat. The strong sulphuric acid of commerce, when poured upon sugar of lead in powder, decomposes it with effervescence, and disengages vapours of acetic acid.

350This must be considered as an active preparation, and may, when administered in doses of a few drachms, speedily occasion death. At the same time, like other poisons, it may by judicious administration, become a valuable remedy. See Pharmacologia, art. Plumbi Super-acetas.

In consequence of the sweet taste of this salt, children have been induced to swallow it.

Goulard’s Extract. Liquor Plumbi Sub-acetatis.

This liquor is a saturated solution of the sub-acetate of lead. Spring water, from the salts which it contains, produces with it a very milky and turbid appearance; and even when distilled, in consequence of the carbonic acid diffused through it, it will occasion precipitation. It is principally used as an external application to diminish inflammation, an effect which it probably produces by paralysing the nerves of the part. Cases have occurred where this lotion has been accidentally swallowed, and the usual symptoms of saturnine poisoning have supervened. How far its external application may be capable of occasioning mischief, will form a subject of inquiry under the consideration of the physiological action of the preparations of lead.

White Lead. Sub-Carbonate of Lead. Cerusse.

The substance, known in commercial language by the name of White Lead, has received at different times, very various appellations, in consequence of the fluctuating opinions which have prevailed respecting its composition. Thus it has been successively styled a sub-acetate, an oxide, and a sub-carbonate; 351of which the last is unquestionably the correct name. In the large way it is prepared by exposing sheets of metallic lead to the fumes of vinegar. The sub-carbonate so produced appears as a white, brittle, and scaly substance, on the surface of the lead; which is scraped off, and afterwards ground in mills fitted for the purpose. Formerly, it was ground dry, and the workmen suffered severely from the operation; it is now ground in water, and the sub-carbonate is afterwards dried in earthen pans placed in stoves, heated by means of flues; still, however, persons employed in grinding white lead, as well as painters^[375] who are constantly using it, occasionally suffer severely, from the want of cleanliness in not washing their hands before eating, by which some of the white lead is introduced into the stomach with their food.

Litharge. Semi-vitrified Oxide of Lead.

This is a yellow protoxide of lead, which has been melted, and left to crystallize by cooling. It is in the form of small reddish, or yellowish scales, which are brilliant and vitrified. Its character is so peculiar that it cannot easily be mistaken. It is employed for various purposes in the arts, and is the saturnine preparation more usually selected for the purpose of removing acidity from wines, as above related.

When treated with a muriatic salt, and submitted to a high temperature, a muriate of lead is produced, of a bright yellow colour, the brilliancy of which may be much heightened by grinding it as usual with oil. In this state it forms the pigment known by the name 352of Turner’s yellow, or patent yellow.^[376] It is very poisonous.

Red Lead. Minium.

This red oxide of lead is easily distinguished by its colour, weight, and the facility with which it yields metallic lead, when heated with carbonaceous matter. Common red wafers, which derive their colour from this oxide, afford a striking illustration of this fact, for if burnt in a candle, globules of metallic lead will be observed to flow from them. It is poisonous; and we have already alluded to a case where Gloucester cheese^[377] occasioned deleterious effects, in consequence of its adulteration with red lead. (p. 277) It is destructive also to inferior animals, apparently in very small quantities; red wafers prove poisonous to birds who may pick them up; and the same paste is sold for the purpose of destroying beetles, in which it succeeds very effectually. Since it is employed as a pigment, it may on many occasions prove an accidental cause of poisoning; there is indeed one very common and dangerous source, mentioned by Sir George Baker,^[378] which deserves to be particularized in this place, viz. the practice of painting toys with red lead, and other poisonous substances; children, observes this distinguished physician, are apt to carry every object which gives them delight to their mouths, the painting of toys, therefore, with poisonous colours, 353is a practice which ought to be abolished, and is the more open to censure, as it is of no real utility.

Symptoms of poisoning by the different preparations of Lead.

The effects of this poison will vary considerably according to the quantity swallowed, and the circumstances under which it is taken. We shall, therefore, first consider its operation, in doses sufficiently large to occasion at once violent effects; and then describe its agency as an accumulative poison, where it is introduced into the system gradually, and in small quantities, so as to act slowly and imperceptibly, and to lay the foundation of irreparable mischief, before any alarm is occasioned.

1. Symptoms which follow a large dose. Where a salt of lead has been taken in a considerable dose, the patient soon experiences excruciating pains in the abdomen, accompanied with sickness and vomiting; the colic increases to a violent degree, but admits of temporary alleviation by pressure, a circumstance which at once distinguishes it from the effects of corrosive poison. Although it is necessary to observe, that inflammatory symptoms may afterwards occur, where the dose has been very considerable, and the consequences direct and speedy.

The patient describes the pain as if produced by a boring instrument, and the abdominal muscles become knotted, and sometimes painfully retracted with all the contents of the abdomen towards the spine.^[379] The sphincter muscles of the bladder and anus are 354always affected; sometimes strangury and tenesmus are the consequences; at other times, a total incapacity of making any water at all, and so great a contraction of the sphincter ani that a clyster can hardly be introduced. After suffering these torments for a period of an indefinite duration, delirium and cold sweats may supervene, and the patient die in convulsions. If, however, the treatment has been prompt and judicious, and the quantity of poison has not been excessive, he may recover from its immediate effects, and live to testify the severity of the consecutive phenomena. A most inveterate constipation of the bowels will continue for a considerable period, and there will be an occasional recurrence of colic; at length a peculiar species of palsy will supervene in the upper extremities, especially affecting the muscles of the fore arm, and wrist,^[380] Citois has given us a striking description of this stage of the saturnine disease. “Per vicos, veluti larvæ, aut arte progredientes statuæ, pallidi, squalidi, macilenti conspiciuntur, manibus incurvis et suo pondere pendulis, nec nisi arte ad os et cæteras supernas partes sublatis, ac pedibus non suis, sed crurum muculis, ad ridiculum, ni miserandum, incessum compositis, voce clangosa et strepera.” It does not appear that the train of symptoms above described has ever been excited by any other external cause than the one here assigned. Whenever we meet with colic, attended with paralytic symptoms of the extremities, we may at once conclude that it has arisen from the influence of lead.

The disease has been described by authors under 355the name of the colic of Poitou,^[381] or colica Pictonum,^[382] from the circumstance of its having raged with such epidemic fury in that province, in consequence of the adulteration of its wines with lead. It is also mentioned as the painter’s colic, since this class of artists is very commonly visited by the disease, in consequence of the white lead contained in their pigments. At the Lead Hills, it is known to the miners, under the provincial name of milreek; and in Derbyshire, under that of belland.^[383]

2. Symptoms arising from the introduction of lead into the system, by small and repeated doses.

The effects produced upon various artists by the imperceptible operation of lead, sufficiently shew the power which this metal possesses of accumulating in the human system, and it is probable, says Sir George Baker, that from an observation of such slow, but certain effects of lead, the French and Italians derived the hint of preparing their celebrated poisons, called “Poudres de Succession;”^[384] the basis of which has been supposed to have been some preparation of that mineral. Zeller mentions a certain chemical operator, near the confines of Bohemia, who, after having diligently applied himself to the composition of poisons, did, by means of lead, combined with some more volatile and corrosive substance, prepare a most slow poison, which given to dogs and 356other animals, had the power of destroying them, without producing any violent symptoms, after several weeks, or even months.^[385]

The following-curious case,^[386] communicated by Dr. Wall, of Worcester to Sir George Baker, will serve to illustrate the present subject, and to shew that lead may gain admittance into the human body, unobserved, and even unsuspected. “A gentleman of Worcester was the father of a numerous offspring, having had one and twenty children, of whom eight died young, and thirteen survived their parents. During their infancy, and indeed until they had quitted the place of their usual residence, they were all remarkably unhealthy; being particularly subject to disorders of the stomach and bowels. The father, during many years, was paralytic; the mother, for as long a time, subject to colics and bilious obstructions. She died at last of an obstinate jaundice. This disease had been several times removed by the use of the Bath water; but it always came on again soon after her return to Worcester; and at last eluded every method and medicine which was tried. After the death of these parents, the family sold the house which they had so long inhabited. The purchaser found it necessary to repair the pump. This was made of lead; and, upon examination, was found to be so corroded, that several perforations were observed in the cylinder, in which the bucket plays; and the cistern in the upper part was reduced to the thinness of common brown paper, and was full of holes like a sieve. The waters of this town are remarkably 357hard. It is then more than probable that the water of this pump, thus impregnated with lead, occasioned the unhealthiness of the family who drank it. I have been just informed by the plumber,” adds Dr. Wall, “that he had several times repaired the pump in question; and that he had done so not more than three or four years before the gentleman’s death; when he found it nearly in the same state as it has been described; so that the corrosion was effected in a short time; and consequently the water must have been very strongly impregnated with the noxious quality of the metal.”

Organic lesions discovered on dissection.

The reports of the dissection of those who have been destroyed by saturnine poisons are far from being satisfactory. Where the person has died from the primary effects of a large dose of the acetate of lead, the stomach has betrayed a state of inflammation, similar to that which results from the action of a corrosive poison; black points and spots, from venous extravasation, have been also observed in the interior of this viscus; M. Orfila states that he has seen in the stomach of animals who have taken a large dose of the acetate of lead, and have not vomited, a membraneous lining tolerably thick, of an ash colour, easily detaching in small pieces; the origin of which appeared to be owing to the decomposition of a part of the acetate of lead by the mucous, bilious, and other fluids, contained in this viscus. The mucous membrane lying under this lining, was of a dark grey colour throughout its whole thickness, and appeared to have exercised the same action on the acetate of lead. The case is very different in those who have 358died from the slow action of this metal; all anatomists agree in reporting, that in the colica pictonum, the digestive canal exhibits no vestige of inflammation;^[387] but the diameter of the large intestines, especially that of the colon, is generally contracted; thus displaying the effects of that operation, which is supposed to be characteristic of the compounds of lead, and which has bestowed upon them the peculiar designation of astringent poisons. Foderé states that the mesentery and its glands; and the lacteal and lymphatic vessels, are inflamed and obstructed, and the thoracic duct almost obliterated; the liver, spleen, pancreas, and lungs often inflamed, tumefied and purulent, and even the heart shrivelled;^[388] and the whole body, in consequence of the constriction of the chyliferous vessels, in a state of complete marasmus. Upon this passage Orfila makes the following observation. “We are under the necessity of declaring, that almost all these signs are wanting in the majority of the cases of simple colic of lead, terminated by death.” Fourcroy, in a note to his translation of Ramazzini, “De Morbis Artificum,” observes that the intestines have, in these cases, been discovered distended by air, parched, and slightly altered in colour; and that in the larger ones, balls of dry, dark coloured, excrementitious matter, have been found.

Physiological action of Lead Poisons.

The preparations of lead seem to act upon the nervous system, destroying its energy, and thereby producing paralysis. Whether this is effected through 359the medium of the circulation, or whether they produce their effects without being absorbed, appears to us to be a question which has not hitherto received a satisfactory answer. It must, however, be admitted that they act upon the alimentary canal, by coming into contact with its nerves; and in some cases, where the dose of the acetate has been large, it may have produced death by the local injury which it inflicted. Dr. Lambe observes upon this subject, that “certain facts render it probable that lead does not operate entirely through the medium of the circulation, nor by nervous sympathy; but also topically, affecting the part to which it is applied more than the other parts of the body.” This latter position is clearly established by the beneficial effects occasioned by the topical application of lead to inflamed surfaces; nor can any doubt exist as to the fact of such applications having produced local paralysis. There is a paper in the third volume of the Medical Transactions by Dr. Reynolds, in which the case of a gentleman is detailed, who brought on a temporary paralysis of the sphincter ani, by freely using Goulard’s lotion for the cure of piles. Foreign writers have also maintained that saturnine applications have frequently occasioned impotence; for further information upon this subject the reader may refer to Istitutione di Medicina Forens: di Tortosa, vol. 1, p. 58; also Fritze Compend: sopra i Malat. Vener. p. 189; and Monteggia Annotat. sopra i Mali Venerei, p. 36. Sir George Baker states that he has some reason to doubt, whether litharge, the common basis of our plasters, when used for the purpose of dressing issues, has not, in certain irritable constitutions, produced some of the ordinary effects of saturnine preparations taken internally. There have been instances of children 360thrown into convulsions, by cerusse, sprinkled on excoriated parts. Zeller quotes, on the authority of Molingius, a remarkable instance of the pernicious effects of litharge, externally applied.^[389] Sir George Baker met with a most violent and obstinate colic, which seemed to have been occasioned by some litharge, mixed in a cataplasm, and applied to the vagina, with a view to allay a troublesome itching; and he says that he was informed by Dr. Petit that Goulard’s poultice applied for some time to a patient’s knee, in St. George’s hospital, occasioned violent pain in the bowels, which did not cease until the poultice had been removed; nor are authorities deficient to prove, that the fashionable application of cerusse to the skin has been followed by obstinate colics, pains, and tremors. We have been desirous of laying before our readers the above authorities, in proof of the constitutional effects which may be occasionally produced by the external application of lead, since the fact has been questioned, and is still considered by many as involved in doubt and uncertainty. Dr. Lambe is inclined to believe, that “to the production of the saturnine colic, it is necessary that the metal should be applied immediately to the stomach and intestines.” If this hypothesis be just, he excludes nervous sympathy, as well as absorption, as a proximate cause of saturnine colic; and, consequently, no dependence can be placed on the accounts given by the above pathologists with regard to the production 361of such an effect by lotions and cataplasms of lead.

Of the chemical processes, by which the presence of lead may be detected.

These will necessarily vary according to the different states of combination in which it may be supposed to exist; we shall, therefore, proceed to consider the modes of establishing its presence, 1, In solution in water; wine; spirit; and oils. 2. In a state of mixture with various solids. 3. Combined with solid or liquid aliments.

1. The lead exists in some unknown state of combination in solution in water. We are greatly indebted to Dr. Lambe^[390] for the able directions which he has afforded us for ascertaining the presence of minute portions of lead in water; and we recommend the practitioner, who may be engaged in such an investigation, to peruse his work with attention. The following are the reagents through which our analysis must be conducted.

(a) Sulphuretted hydrogen. A solution of this gas in distilled water is a very delicate test for lead, throwing down a precipitate of a very dark brown colour, approaching to black. The competency, however, of this test to the discovery of very minute quantities of lead, in certain states of combination, has been questioned by Dr. Lambe; who was enabled to detect the presence of this metal, by other methods, in water that manifested no indication with sulphuretted hydrogen. He detected it, for instance, in the precipitate occasioned in such water by the 362carbonate of potass or soda. In operating on these waters, he noticed the following appearances.

1. The precipitate, produced as above stated, when re-dissolved in nitric acid, formed a dark cloud with sulphuretted hydrogen.

2. Although the sulphuretted hydrogen formed no cloud, the precipitate itself became darkened by it.

3. The precipitate re-dissolved in nitric acid, (as in 1) formed, with sulphuretted hydrogen, a white cloud.

4. Sulphuretted hydrogen neither formed a cloud, nor darkened the precipitate.

5. In the cases 2, 3, 4, if the precipitate be heated to redness, in contact with an alkaline carbonate; and after dissolving out the carbonate, it be redissolved in nitric acid; then sulphuretted hydrogen will form a dark cloud with the solution. In these experiments it is necessary that the acid used to redissolve the precipitate be not in excess; if it should so happen, the excess must be saturated, before the test is applied. It is better to use so little, that some precipitate may remain undissolved. The nitric acid, used in these experiments, should be perfectly pure; and the sulphuretted hydrogen test should be recently prepared by saturating distilled water with the gas.

(b) Sulphate of soda, or potass. This test will produce a white precipitate in water, containing one hundred-thousandth of its weight of lead; and is considered by Dr. Thomson as the most unequivocal reagent 363of that metal which we possess. “The precipitate is a fine dense powder, which speedily falls to the bottom, and is not re-dissolved by nitric acid; no other precipitate can be confounded with it, except sulphate of baryta, and there is no chance of the presence of baryta in solution in water.”^[391]

(c) Muriate of soda. One of the methods of analysis proposed by Dr. Lambe, consists in precipitating the lead by common salt; but as the muriate of lead is partly soluble in water, this test cannot be applied to small portions of suspected water. The precipitate must, therefore, be collected from two or three gallons, and heated to redness with twice its weight of carbonate of soda. The alkaline carbonate is then to be dissolved out, and nitric acid added, in order to saturate any superfluity; the sulphuretted hydrogen test will then produce its indication.

(d) Reduction of the metal. This is undoubtedly the most satisfactory of all the tests; and, except the trouble of collecting a large quantity of precipitate, is not embarrassed with any difficulty. The precipitate may be mixed with its own weight of alkaline carbonate, and exposed either with, or without, the addition of a small proportion of charcoal, to a heat sufficient to melt the alkali. On breaking the crucible, a small globule of lead will be found reduced at the bottom. The precipitate from about fifty gallons of water yielded Dr. Lambe about two grains of lead.

2. The lead is dissolved in wine. For the detection of this dangerous fraud, the reagent invented by Dr. Hahnemann affords a ready and convenient test. It consists of water saturated with sulphuretted hydrogen 364gas, and acidulated with muriatic acid;^[392] this latter ingredient is added for the purpose of preventing the precipitation of any iron, which the wine might accidentally contain. This liquor will, if added in the proportion of one part to two of wine, produce with the smallest quantity of lead, a dark coloured, or black precipitate; which, if collected, dried, and fused before the blow-pipe on a piece of charcoal, will yield a globule of metallic lead. Or we may modify the experiment by passing a current of sulphuretted hydrogen gas through the wine, having previously acidulated it with muriatic acid, to prevent the precipitation of the iron.

A farther proof of the presence of lead in wines is the occurrence of a precipitate, on adding a solution of the sulphate of soda.

The most satisfactory proof, however, is derived by distilling off the alcohol, and calcining the residuum with charcoal, in order to obtain the metallic lead.

The quantity of lead which has been detected in sophisticated wine, may be estimated at forty grains of the metal in every fifty gallons,^[393] but this will of course be liable to vary with the degree of acidity it was intended to correct.

3. The lead is dissolved in oils. In this case the lead may be detected by shaking, in a stopped phial, one part of the suspected oil, with two or three parts 365of water, impregnated with sulphuretted hydrogen. This test will announce the presence of the deleterious metal, by occasioning a dark brown, or black colour.

4. The lead is mixed with alimentary matter. M. Orfila has furnished us with the following directions for assaying the matter vomited, or that which may be found in the digestive canal, after death. “After having expressed the fluid portion through a piece of fine linen, it must be assayed by the tests, which have been already enumerated as being capable of detecting the salts of lead; and if the precipitates obtained are of a nature to induce a belief, that the fluid contains some preparation of this kind, it must be evaporated to dryness, and calcined with charcoal in a crucible; when, at the expiration of three quarters of an hour, metallic lead will be obtained. If all the experiments made on the fluid portion of the matter vomited, for the discovery of this poison, should be fruitless, the whole of the solid portions, previously dried, should then be calcined with potass and charcoal, by which means metallic lead will be obtained.”

366

VEGETABLE POISONS.

The poisons of which we are about to offer the physiological and chemical history, although more numerous than those which belong to the mineral kingdom, are, notwithstanding, of far less importance in a forensic point of view. With the exception of opium, and some few others, they must be considered as objects of accidental, rather than of criminal poisoning; and even with respect to the former narcotic, it may be said to afford more frequently the means of destruction to the suicide, than to the assassin.

The sensible qualities of smell, taste, and sometimes colour, which so eminently characterise deleterious plants, must necessarily render them ill calculated to favour that secresy, which constitutes the indispensable companion of crime; while their bulk, and the pharmaceutical preparation which they require, are alike inconsistent with the hope of concealment.

Thus we receive, as it were, from Nature, that protection which art can no longer supply; and the commission of crime is either prevented or discovered, in cases where the powers of chemistry would fail in its detection.

The objects which constitute the vegetable kingdom differ from every species of mineral matter, not only in their peculiar organized structure, but in the chemical arrangement of their elements; those of inorganic matter are generally combined in very simple proportions, 367as one and one, or one and two, &c. whereas in organized bodies, their proportions are much more complicated; and Dr. Ure observes,^[394] that such substances derive the peculiar delicacy of their chemical equilibrium, and the consequent facility with which it may be subverted and new modelled, to the multitude of atoms grouped together in a compound; hence too, as Mr. Children^[395] has observed, is one reason of our utter inability to reproduce even the simplest body of this class, when once its elements have been separated; it is not in the diversity of these elements, but in the manner in which they are grouped, that this peculiarity consists, for, continues the accomplished chemist last mentioned, “vegetable substances seldom contain, as essential, more than three principles—oxygen, hydrogen, and carbon, and sometimes azote. With four simple elements then, a brief alphabet for so comprehensive a history! has a bountiful Omnipotence composed the beautiful volume of the living world, where, turn to what page we may, fresh loveliness meets the eye, fresh cause of admiration and delight.”

The analysis of vegetable bodies resolves itself into two parts, each of which constitutes an equal object of interest to the forensic physician; who, it will be shewn, may occasionally derive important information from both. The first relates to the discovery of the proximate principles of a vegetable substance. The second, to that of its ultimate elements. By the proximate, or, as they are sometimes termed, the immediate principles, we mean those compound substances which exist in the living plant in a state identical 368with that, under which chemical processes exhibit them, and are chiefly separable by the action of different solvents. The number of these principles is considerable, as gum, starch, sugar, gluten, extractiue, tannin, oils, acid, &c. &c. By the ultimate elements, we understand those, of which the proximate are composed, as oxygen, hydrogen, carbon, and azote. In submitting a plant to destructive analysis, for the purpose of obtaining its ultimate elements, we shall derive compounds, which formed no part of the vegetable structure, and which result from a new arrangement of the elements composing it; acetic and carbonic acids, for example, are obtained by the destructive distillation of several vegetable substances, in which neither of these acids existed ready formed, but only their elements.^[396] It may easily be imagined to what numerous fallacies such a law of composition must have given origin, in the earlier periods of chemical inquiry; and it is equally evident, that the utmost refinement of chemical science, and the most rigorous methods of analysis, will be required to enable us to deduce any satisfactory conclusion with respect to the quality of a plant, from these data. Such perfection, indeed, has not hitherto been attained, but the period is probably not far distant, when our most sanguine anticipations upon this point may be realised. We have only to trace the history of this branch of chemistry for the last century, to become satisfied of its gradual and important progress towards such an epoch, and of the improvements of which this department of vegetable analysis is farther susceptible; let us, for the sake of illustration, 369only compare the rude results obtained by the academicians of Paris, at about the commencement of the seventeenth century, with those of MM. Gay-Lussac and Thenard^[397], or with those, very lately instituted in this country by Dr. Ure,^[398] and we shall perceive that while the former of these experimentalists, by the aid of heat, were unable to form the slightest distinction between the most inert, and the most poisonous species of plants, the latter, by means of the same agent, aided by the modern doctrine of equivalent ratios, has succeeded in establishing the proportions in which the elements of each vegetable body combines; and with such accuracy, as to discriminate between substances, which bear the greatest analogy to each other; as between the varieties of sugar, and those of oil; and even between common flax, and the same substance prepared according to the improved process of Mr. Lee. This statement is sufficient to show the capability of ultimate analysis, on certain occasions, to identify vegetable bodies; but we are, at present, scarcely advanced far enough in such an investigation, to make it subservient to the detection of vegetable poisons. Nor has our knowledge with regard to proximate analysis, been less successfully advanced. The late researches of the French and German chemists have demonstrated the existence of several new alkaline bodies in the class of vegetable poisons, to which some of these plants appear to be exclusively indebted for their activity, as the poppy, hellebore, colchicum, &c.; and whose characters are so distinct and striking, as to enable the chemist to recognise 370their presence by appropriate re-agents. In other cases, the virulence of a plant would appear to depend upon the combination of several^[399] proximate principles; while in some few instances there exist in the same individual vegetable, two distinct elements of activity, as illustrated by the interesting history of tobacco.

In cases of vegetable poisoning it will occasionally occur, that some remains of the plant may be collected; and seeds, portions of the fungi, and leaves, may be found in the contents of the stomach; whence a knowledge of botany becomes indispensable. This branch of science is, moreover, important to the toxicologist, as enabling him to pursue the study of plants with greater precision; for experience has shewn that there is a wonderful analogy between the structure of those plants which resemble each other in medicinal operation. Thus those which, from their dismal and dusky appearance, have been arranged under the title of Luridæ, are in general highly poisonous; they also possess a very peculiar and disagreeable smell, so that Nature has, upon this occasion, kindly given us notice of approaching danger, by means of our senses.

Of equal importance with the knowledge of the generic and specific characters, is that of their sensible qualities, and the changes which these latter undergo by pharmaceutical preparation.

371

Cl. III. ACRID, or RUBEFACIENT POISONS.

Most of the subjects of this class constitute articles of Materia Medica; so that ignorance on the one hand, and accident on the other, may render them the unexpected source of mischief. With respect to the physiological action of these bodies, the reader has only to refer to our classification at page 207, to perceive that it will not admit of generalization; for each division, it will be observed, contains individuals which belong to the class of acrid poisons.

As the history of most of these articles is to be found in works on Materia Medica, we shall not enter so fully into their properties, as we might otherwise have considered necessary.

Camboge or Gamboge.

This beautiful gum-resin is obtained by making incisions in the leaves and young sprouts of the Stalagmitis Cambogioides^[400] (Polygamia Monæcia—Nat. ord. Tricoccæ. Wild:) It is first collected, in the kingdoms of Siam and Ceylon, in cocoa-nut shells, and is thence transferred into large earthen jars, where it remains until it is nearly dried to a cake, when it is formed into rolls, and wrapped up in leaves. It is imported into Europe^[401] in cases and boxes. Its deep yellow colour, which is so materially brightened by being wetted, and its shining fracture, are characters sufficiently striking to 372enable the practitioner to identify it; and when we add to these the history of its habitudes with different menstrua, the chemist will have no difficulty in detecting its presence, viz. when triturated with water, two-thirds of its substance are speedily dissolved, and a turbid solution results; alcohol dissolves nine-tenths, and forms a yellow transparent tincture, which is rendered turbid by the addition of water; sulphuric ether dissolves six-tenths of the substance; it is also soluble in alkaline solutions, and the resulting compound is not rendered turbid by water, but is instantly decomposed by acids, and the precipitate so produced is of an extremely brilliant yellow colour, and soluble in an excess of acid.

Its action upon the animal œconomy is that of a powerfully drastic purge. We are, however, not acquainted with any case in which death followed its administration. From the experiments made upon animals, it would appear to produce its effects by a local action on the textures, with which it comes in contact, and it will accordingly be found in the third class of our physiological classification, (page 207.)

White Hellebore.^[402] Veratrum Album. (Polygamia—Monæcia—Nat. Ord. Coronariæ. Linn.—Junci. Juss.)

This is undoubtedly the true hellebore of the ancients. It is a native of the mountainous parts of Greece, Italy, Switzerland, and Russia. Those specimens which are cultivated in our gardens flower in July. The root is the only part employed in medicine, but every part of the plant is extremely acrid and poisonous. Upon the animal œconomy it acts as 373a violent cathartic and emetic; producing bloody stools, excessive vomitings, great anxiety, vertigo, tremors, sinking of the pulse, syncope, cold sweats, convulsions, and death. There are many cases on record, where such effects have followed the ingestion of this plant. Helmont reports that a royal prince died in the course of three hours after taking a scruple of this poison, which induced convulsions; and Vicat^[403] relates the case of a tailor, his wife, children, and workmen, who having taken soup, in which, through mistake, the root of white hellebore had been introduced instead of pepper, were seized with a universal coldness, and such extreme debility, as to become nearly insensible. At the expiration of two hours, the eldest child, who was not four years of age, began to vomit copiously, but with considerable straining; the rest were shortly after in the same condition. Vicat, who was called in at this critical period, ordered them to take a considerable quantity of warm water and oil; shortly after which he administered an infusion of mallow sweetened with honey; by which means, we are informed, they were relieved, and ultimately restored. According to the testimony of various physiologists, as well as from the experiments of Orfila, it appears that this plant, if externally applied, will produce the same effects. Etmuller says, that the external application of the root to the abdomen will produce vomiting; and Schroeder observed the same phenomenon to take place in a case where it was used as a suppository; the juice of the plant has been also applied to the purpose of poisoning arrows. It must, therefore, act by being absorbed into the circulating current, thereby destroying the energy 374of the nervous system. It accordingly finds a place in the second division of our classification. Late experiments upon this substance have shewn that its activity depends upon a peculiar alkaline principle, to which the name of veratria^[404] has been given; and that it exists in native combination with an excess of gallic acid, (super-gallate of veratria).

When taken internally, as a poison, the most effectual antidote is said to be a very strong infusion of nut-galls.

Black Hellebore. Melampodium. Christmas-rose. (Polyandria Polygynia. Nat. Ord. Multisiliquæ, Linn. Ranunculaceæ, Juss.)

This plant, which has derived its name from the dark colour of the root, is a native of Austria, the Apennines, and Italy; it has, however, obtained a place in our gardens,^[405] and from the circumstance of its flowering from December till March, it has acquired the name of the christmas rose. The fibres of the roots are the parts employed in medicine; their odour is fœtid, and their taste bitter and acrid. Its action upon the animal œconomy is similar to that of the preceding species. Morgagni relates the history of a person who took half a drachm of black hellebore, and expired eight hours afterwards. M. Orfila states that inflammation of the rectum is a constant occurrence, where the animals who have taken this root, have survived its administration for a few hours.

375

Fœtid Hellebore. Helleborus Fœtidus. Helleboraster.

This plant is a native of England, growing in shady places, on a chalky soil, and flowering in March and April. Like the former species of hellebore, it is capable of producing fatal effects. A case is related in the London Chronicle, 1768, no. 1760, of a child who died in consequence of taking the root of this plant in the pulp of an apple.

Elaterium. Wild, or squirting Cucumber. Momordica Elaterium (Monæcia Monadelphia. Nat. Ord. Cucurbitaceæ.)

This plant is a perennial native of the south of Europe, flowering in June and July; it is cultivated in England, but does not survive the severity of our winters. The fruit (poma) has the appearance of a small oval cucumber, of a greyish colour, and covered with prickles. When fully ripe it quits the peduncal, and casts out the seed and juice, with great force, and to a considerable distance, through the hole in the base where the foot-stalk is inserted, whence the name of squirting cucumber. The author has instituted numerous experiments upon this plant, the results of which will be found fully detailed, under its history, in the fifth edition of his Pharmacologia.

The plant appears, from the testimony of Dioscorides, and other writers, to have been employed by the ancient physicians with much confidence and success as a cathartic; all the parts of the plant were considered as purgative, although not in an equal degree; thus Geoffroy, “radicum vis cathartica major 376est quam foliorum, minor vero quam fructuum.” This question, however, has been very lately set at rest, by the valuable experiments of Dr. Clutterbuck,^[406] which prove that the active principle of this plant resides more particularly in the juice which is lodged in the centre of the fruit. The forensic physician, however, will scarcely be liable to meet with a case of poisoning by the fruit of this plant. It is from that preparation of the juice, which is admitted into our Pharmacopœia, under the title of Extract of Elaterium, that we may expect to meet with mischief.

This substance subsides spontaneously from the juice of the fruit; and occurs in commerce in little thin cakes, or broken pieces, bearing the impression of the muslin upon which it is dried; its colour is greenish, its taste bitter, and somewhat acrid; and when tolerably pure it is light, pulverulent, and inflammable. Notwithstanding its extreme activity, it does not, according to our experiments,^[407] contain more than a tenth part of active matter, which is a vegetable proximate principle, sui generis, and to which we have given the name of Elatin. By treating the Elaterium with alcohol, this principle may be obtained; it imparts to the spirit a most brilliant, and beautiful grass green colour—but see our experiments upon this subject. The action of elaterium is that of a most violent drastic cathartic, especially affecting the rectum. It destroys life by its local action, and consequently finds a place in the third division of our classification.

377

Colocynth. Coloquintida; Bitter Apple.

This is the fruit of the Cucumis Colocynthis (Monœcia Monodelphia, Nat. Ord. Cucurbitaceæ) an annual of Turkey and Nubia. It is of the size of an orange, of a yellowish-white colour, devoid of smell, round, dry, light, spongy, and smooth on the outside, when ripe; it is trilocular, each cell containing many ovate, compressed, whitish seeds, enveloped by a white spongy pulp. It is imported into this country, after having been peeled, and dried in a stove. Its taste is extremely bitter and acrimonious. It acts upon the human body as a powerfully drastic purgative. Fordyce,^[408] relates the case of a woman who was subject to colics for the space of thirty years, in consequence of having taken an infusion of this fruit in beer. Tulpius^[409] has also furnished us with an account of the tremendous effects produced by an overdose of the same article; and Orfila has shewn, with his usual accuracy, that it acts not only locally upon the primæ viæ, but by being absorbed, and carried into the circulation.

Euphorbium. Euphorbia Officinarum (Dodecandria Trigynia. Nat. Ord. Tricoccæ Lin. Euphorbiæ Juss.)

This gum resin is imported from Barbary, in drops, or irregular tears; its fracture is vitreous; it is inodorous, but yields a very acrid, burning impression on the tongue. Its acrid constituent resides exclusively in that portion which is soluble in alcohol. This poison has been sometimes administered imprudently 378as a purgative when it has produced vomiting, and bloody stools. Lamotte speaks of a clyster prepared with it, which proved fatal. It acts as a caustic upon the textures with which it comes in contact, and thus destroys life by a local action; indeed its nature is so acrid that when applied to the hair, or to warts, it causes them to fall off. Scopoli mentions the case of a person who, having the eye-lids closed, allowed them to be rubbed with the juice of this plant; in consequence of which inflammation followed, and the sight was lost. In pulverizing the gum-resin, the parmaceutist should take the precaution of previously moistening it with vinegar, or the powder will rise, excoriate his face, and excite violent inflammation of the eyes. There are many species^[410] of Euphorbium, or spurge, which are highly poisonous; and, being indigenous, they have frequently proved the cause of mischief; during the last summer the author was consulted on the occasion of a family of children having been seized with a violent inflammation of the eyes, and eruption on the face, when the phenomenon was very satisfactorily traced to the action of the Euphorbia peplus, which was growing very luxuriantly in the garden where the children had been playing.

Savine. Juniperus Sabina. (Diæcia Monadelphia—Nat. Ord. Coniferæ.)

This shrub is a native of the south of Europe and the Levant; but has been long cultivated in our gardens. 379The leaves and tops of the plant have a strong, heavy, disagreeable odour, and a bitter, hot taste, with a considerable degree of pungency; qualities which depend upon the presence of an essential oil. Upon the animal system it acts as a very powerful stimulant, and has been received into the list of the materia medica, as an active emmenagogue; while it has long enjoyed, amongst the vulgar, the reputation of being capable of producing abortion.^[411] Upon this point we have only to observe, that it does not exert any specific action on the uterus; but as a violent medicine, acting upon the general system, it might, in common with other stimulants, produce so much disturbance as to be followed by abortion. The experiments of Orfila have shewn that savine exerts a local action, but that its effects depend principally on its absorption, through which medium it acts on the nervous system, the rectum, and the stomach.

Aconite. Monkshood. Aconitum Napellus (Polyandria Trigynia—Nat. Ord. Multisiliquæ, Linn. Ranunculaceæ, Juss.)

There are several species of aconite, all of which are poisonous. The monkshood is a well known plant, met with in our gardens, and when swallowed in any quantity will produce the symptoms, characteristic of vegetable poisons. All the parts of aconite, in the fresh state, when chewed, produce a sense of heat, and shortly afterwards a sensation of numbness in the lips and gums, which does not subside for several hours.

380In ancient authors, we frequently meet with aconite as a poison, but it has been fairly questioned whether any particular plant was designated by the term^[412]; like that of cicuta, it seems to have been a word expressive of poisons generally. The most powerful form in which this vegetable poison exists is in that of extract, or inspissated juice^[413], and, if prepared according to the improved process of Mr. Barry,^[414] it will prove highly dangerous in small doses. M. Orfila relates several fatal accidents from the ingestion of this plant; his experiments have also shewn that it will produce its effects by an external application. We agree, however, with Mr. Brodie in considering that it acts, without being absorbed, on the brain, through the medium of the nerves; and we have accordingly placed it in the first division of our classification.

The plants already enumerated are sufficient to illustrate the symptoms and physiological action of the acrid poisons of the vegetable kingdom. We shall, therefore, conclude the history of this class with some account of the nitrate of potass, which has been ranked both by Fodéré and Orfila under this division of their classification.

381

Nitre. Nitrate of Potass.

The sensible qualities of this salt are too well known to require any description. It generally occurs crystallized in six-sided prisms, terminated by dihedral summits. It is composed of one proportional of nitric acid, and one proportional of potass. It dissolves in seven parts of water at 60°, and in its own weight at 212° Fah. Its solution is attended with a great reduction of temperature. It is permanent in the air, melts when exposed to a moderate heat; and, when cast into moulds, constitutes what is known in commerce by the name of sal prunelle. When mixed with inflammable matter it undergoes, in a strong heat, a rapid species of combustion, which, in chemical language, is termed deflagration. Concentrated sulphuric acid, when poured upon this salt in powder, decomposes it at the ordinary temperature, and disengages vapours of nitric acid, which are white, and not very abundant.

Symptoms of poisoning by Nitre.

This salt, when taken in a large dose, acts violently on the stomach and bowels, and occasions syncope and death. There are several cases recorded of its having been taken by mistake for Glauber’s salt.

On these occasions, the patients have been seized with violent vomiting and purging of blood, attended with severe pains in the bowels, and a sense of burning heat, referred to the chest and stomach; cold extremities, fluttering pulse, laborious breathing, syncope, and death. The above effects have been produced by an ounce and a half of nitre; although, as 382Dr. Gordon Smith has observed, the same quantity of this salt has been inadvertently swallowed without the production of such tremendous consequences.

From the experiments of Orfila, it appears that if this salt be inserted into a wound, it occasions a fatal gangrene. Its action is undoubtedly the effect of its acrid nature, destroying the vitality of the textures with which it comes in contact. It is not absorbed.

Organic lesions discovered by dissection.

In those recorded cases of death from the ingestion of nitre, the stomach has been found red, scattered over with blackish spots, and its mucous membrane disorganized.

Chemical processes for the detection of Nitre.

The property which this salt possesses of deflagrating with combustible bodies, affords a ready indication of its presence. The process also, which we have described under the history of nitric acid, (p. 312) as the one suggested by Dr. Wollaston, and adopted by Dr. Marcet in his examination of sea water, furnishes an elegant mode of ascertaining the presence of a nitric salt.

Cl. IV. NARCOTIC POISONS.

These constitute a class of vegetable poisons, less extensive, perhaps, but of far greater importance and interest, than the one we have already considered. It would not be easy to enumerate the various purposes to which the active imagination of man has applied the tribe of narcotic plants. Medicines, poisons, 383intoxication, and madness, lie concealed beneath their juices. They have, in their turn, arrested the pangs of disease, and inflicted death upon the unsuspecting object of hatred and revenge; they have animated the courage of the warrior, inspired the enthusiasm of the poet, soothed the sorrows of the wretched, and furnished the debauchee with a daily source of sensual gratification; effects which, although apparently incompatible with each other, may be commanded by the same substance, in a different dose. It would be foreign to the plan of this work to enter into a physiological inquiry into the modus operandi of these extraordinary agents; and the author relinquishes the labour with less regret, as he has already, in another work,^[415] very fully considered the several theories which have been advanced for its explanation.

Opium, and its Preparations.

This well known drug is the inspissated juice of the Papaver Somniferum (Polyandria Monogynia. Nat. Ord. Rhoedææ, Linn. Papaveraceæ Juss.) obtained by making incisions in the half ripe capsules, at sun-set, when the night dews favour the exudation of the juice, which is collected in the morning by old women and children, who scrape it from off the wounds with a small iron scoop, and deposit the whole in an earthen pot, where it is worked by wooden spatulas in the sun-shine, until it attain a considerable degree of spissitude. It is then formed by the hand into cakes, which are laid in earthen basins to be further exsiccated.^[416] Two kinds are found in commerce, distinguished by the names of Turkey, and East Indian 384opium. The latter kind is regarded as being inferior to the former.

Turkey opium occurs in flat pieces, of a solid compact texture, possessing considerable tenacity; its specific gravity is 1·336, so that, when compared with concrete juices of other plants, it is heavy, being exceeded only in this respect by opoponax and gum arabic. It is of a reddish-brown, or fawn-colour, and has a peculiar, heavy, and narcotic odour; its taste is acrid, bitter, and hot. By long exposure to the air, it becomes hard, and breaks with a glimmering fracture, owing to the presence of a few saline particles. It is plastic, and when worked with the fingers is adherent to them. When brought near a lighted candle it inflames, and burns with a brilliant light, but its odour at that time is not narcotic. It is partially soluble in water, alcohol, æther, wine, vinegar, and lemon-juice. When triturated with hot water, five parts in twelve are dissolved, six suspended, and one part remains perfectly insoluble, and resembles the gluten of wheat, but is of a dark colour. The alcoholic is more highly charged with its narcotic principle than the aqueous solution; but spirit, rather below proof, is its best menstruum.

Few vegetable substances have been more frequently, or more ably submitted to analysis; and the history of the successive steps by which our knowledge respecting its composition has advanced, must encourage us in hoping that we shall shortly be enabled to identify, by chemical tests, the presence of opium, with as little difficulty and as great precision as we are already capable of recognising a metallic poison.

According to the latest chemical views respecting the composition of this body, it may be stated to consist 385of the following principles, viz. resin, gum, bitter extractive, sulphate of lime, gluten, and the three lately discovered bodies, narcotine, morphia, and meconic acid.

In the year 1803, Derosne first obtained from opium a crystalline substance, which he found to dissolve in acids, but he does not appear to have instituted many experiments, for the elucidation of its nature and properties. In 1804 Seguin discovered another crystalline body, and although he described many of its properties, what appears very extraordinary, he never even hinted at its alkaline nature. Sertuerner, at Eimbeck in Hanover, had at the same time as Derosne and Seguin, obtained these crystalline bodies, but it was not until the year 1817, that he first proclaimed the existence of a vegetable alkali, and attributed to it the narcotic powers which distinguish the operation of opium; to this body, he gave the name of Morphia, and it would appear to be the same as the essential salt of Seguin. The salt of Derosne was also at first mistaken for the same principle, but the experiments of Robiquet have pointed out its distinctive properties, and it has received the name of Narcotine.

Morphia, upon which the soporific powers of opium depend, appears to exist in native combination with a peculiar acid, to which the name of meconic acid has been bestowed. The following are the essential characters of this alkaline body, when procured in a state of purity.^[417]

It crystallizes in fine, transparent, truncated pyramids, the bases of which are either squares or rectangles, 386occasionally united base to base, and thereby forming octohedra. It is sparingly soluble in boiling water, but dissolves abundantly in heated alcohol, giving rise to an intensely bitter solution; in æther it is far less soluble. It has also the characters of an alkali; affecting test papers tinged with tumeric or violets, uniting with acids and forming neutral salts, and decomposing the compounds of acids with metallic oxides. It unites with sulphur by means of heat, but the combination is no sooner formed than it is decomposed. It fuses at a moderate temperature, when it resembles melted sulphur, and like that substance crystallizes on cooling; it is decomposed by distillation, yielding carbonate of ammonia, oil, and a black resinous residue, with a peculiar smell; when heated in contact with air, it inflames rapidly, and like vegetable matter, it leaves a carbonaceous residue. When analyzed by means of the deutoxide of copper, it yields carbon, hydrogen, and oxygen, the atomic proportions of which have not yet been ascertained. The nitric acid of commerce, when dropped on morphia, communicates to it a beautiful red colour. Sertuerner 387has given us an account of the effect of the alcoholic solution of morphia on himself, and three of his pupils; he found that repeated small doses of half a grain produced at first decided excitation; then weakness, numbness, and tendency to fainting; after swallowing vinegar while in this condition, violent vomiting was excited; in one delicate individual, profound sleep intervened, and on the following day he suffered from nausea, vomiting, head-ache, anorexia, constipation, and heaviness.^[418] This case is sufficient to shew, that although morphia possesses the characteristic powers of opium, its strength is by no means commensurate with its supposed state of concentration. When uncombined, it exerts little or no action, in consequence of its insolubility in water, and in the fluids of the stomach. When, however, it is combined with an acid, particularly the acetic, or the meconic, with the latter of which we have before stated that it exists in opium, it displays its properties in a very eminent degree. It is also very soluble in oil; and, according to the experiments of M. Majendie, the compound acts with great intensity.

The meconic acid, when separated from the residuum of the magnesian salt, as described in the process for the preparation of morphia (note p. 386) does not appear to possess any medicinal activity. Its distinguishing chemical character is, that it produces an intensely red colour in solutions of iron, oxidized ad maximum; and a deep blue, with solutions of the salts of gold. Narcotine is the salt originally obtained by Derosne, and is supposed by MM. Majendie and Robiquet to be the peculiar principle which produces the excitement experienced by those who 388take small doses of opium. It may be entirely removed by macerating the extract of opium in sulphuric æther.

Symptoms of poisoning by Opium.

In considerable doses, the primary action of this substance, as a powerful and diffusible stimulant, is not apparent; for the powers of life are immediately depressed, drowsiness and stupor succeed, and these are followed by delirium, stertorous breathing, cold sweats, convulsions, and apoplectic death.

The quantity of opium necessary for the production of such effects must be regarded as relative. In no two cases can we ensure a similar result, by the administration of the same dose. But, of all the circumstances capable of modifying the power of this drug, habit is the most remarkable; in illustration of which we have only to adduce the history of the opium eater, or laudanum drinker; a species of debauchee by no means uncommon, as every London chemist can testify, for he frequently experiences considerable doubt and difficulty in distinguishing persons, to whom habit has rendered large doses of opium necessary, from such as purchase it with a view to suicide.^[419] The lowest fatal dose, to those unaccustomed to it, seems to be about four grains; but the Turk will take three drachms in the morning, and repeat the same dose at night, without any other effects than that of cheerfulness and exhilaration. This temporary impunity, however, is dearly purchased by years of suffering and sorrow. The effects of opium, says Russel, on those who have been addicted to it, are at 389first obstinate costiveness, succeeded by diarrhœa and flatulence, with loss of appetite, and a sottish appearance; their memories soon fail, they become prematurely old, and then sink into the grave objects of scorn and pity.^[420]

Where a person has, from accident, or design, swallowed a large dose of pure opium, or laudanum, the symptoms produced are so characteristic and striking, that the practitioner, who may be summoned to render assistance, will have no difficulty in ascertaining their cause.

Insensibility, with a scarcely perceptible respiration, although in some cases it is attended with an apopletic stertor; the countenance is livid and cadaverous; the skin cold; and the muscles of the limbs and trunk in a state of extreme relaxation. The pupils are insensible to the impression of light, and the pulse is almost imperceptible. In some stages, the patient, by being strongly shaken, may be roused for a few moments from the lethargy; there is generally a narcotic odour distinguishable in the breath. Vomiting may also take place upon the first impression of the laudanum upon the stomach; although after its action has been displayed upon the brain, it will be difficult to excite emesis by the most powerful means; the reason of which may be very satisfactorily deduced from the ingenious experiments of M. Majendie on the mechanism of vomiting; by which he proves, that without the influence of the brain, the muscles, whose actions constitute an essential part of the operation, are incapable of performing their duty, and that vomiting therefore cannot take place. This is a very important doctrine, inasmuch as it suggests 390to the pathologist several expedients, by which he may be enabled to occasion vomiting, by recalling the excitability of the brain. The period which will elapse, between the ingestion of the poison, and the death of the sufferer, may be stated to be from six to twenty-four hours; but it will in each case be liable to vary, not only from the quantity of opium swallowed, but from the habit and peculiar circumstances of the individual submitted to its operation.

Physiological action of Opium.

It is still a question for the decision of future physiologists, whether the narcotic principle of opium destroys the functions of the nervous system by a local impression upon the stomach,^[421] or by being absorbed,^[422] and brought into contact with the brain in the course of the circulation. We are inclined to adopt this latter opinion, and have therefore placed opium in the second division of our classification; at the same time, we think that it may occasionally produce an effect upon the nervous extremities of the stomach, and we have accordingly placed an asterisk against the word, by which we denote this double mode of operation. But, by whatever medium it may act, it is evident that it occasions death by destroying the functions of the brain; in consequence of which the muscles of respiration, no longer supplied 391with nervous energy, cease to contract, and the animal dies in a state of suffocation.^[423]

Of the treatment in cases of poisoning by Opium.

The first object is the evacuation of the stomach by vomiting; for which purpose, the patient should be made to swallow from fifteen grains to a scruple of sulphate of zinc; or, from five to ten grains of sulphate of copper dissolved in water; and the vomiting should be kept up for a considerable time, and urged by irritation of the fauces. Where the act of vomiting cannot be established, in consequence of the paralysed state of the nervous system, cold affusion, applied by means of a shower bath, has been said to restore the energy of the brain, and thus to render the patient susceptible of the stimulus of an emetic.^[424] Venesection has also, under the same circumstances, been greatly extolled; and, as vascular congestion in the brain is one of the effects of this poison, it is reasonable to conclude that, by unloading the vessels of this organ, we may restore its lost sensibility. Tissot has strongly recommended the practice,^[425] and the experiments of Orfila have shewn that it never aggravated the symptoms of poisoning by opium, nor accelerated the moment of death; but on the contrary, 392that in some instances he found that it restored the animals which would have died, if it had not been put in practice. Where the operation is performed, the blood should be drawn from the jugular vein, in preference to any other. Should these means prove insufficient to provoke vomiting, M. Orfila asks, whether one or two grains of tartarized antimony, dissolved in one or two ounces of water, might not be injected into the veins? It was formerly proposed by Boerhaave to empty the stomach of its poisonous contents, by the introduction of a syringe; an operation which, it is said, has been lately performed with success.^[426] Vinegar and vegetable acids were long considered as antidotes to opium; but the experiments of M. Orfila have clearly established that, as long as any portion of the opium remains in the stomach, these potations, so far from relieving, aggravate the symptoms of poisoning by this narcotic, in consequence of the power which they possess of dissolving it. Where, however, the opium has been expelled by vomiting, these acid drinks possess the property of diminishing the consecutive symptoms, and of thus realising the expectations which Virgil^[427] has so poetically raised,

----“quo non præsentius ullum

Auxilium venit, ac membris agit atra venena.”

The powers of the habit should, at the same time, be supported by brandy, strong coffee, and cordials. The sufferer should be kept awake; and, if possible, 393in a continued gentle motion. Dr. Currie^[428] has recommended the affusion of warm water at 106°, or 108°, for removing the stupor.

A case is recorded by Dr. Marcet, in the first volume of the Medico-chirurgical Transactions, where six ounces of laudanum were taken by a young man, and remained for five hours in the stomach before any remedies were applied for its removal; a strong dose of sulphate of copper, however, provoked vomiting, and by judicious treatment he eventually recovered.

Organic lesions discovered on dissection.

It has been very truly remarked that although the instances in which opium has proved fatal to human life have been very numerous, yet that the accounts which we have received of the appearances of the body post mortem, are by no means so satisfactory as we could desire. M. Orfila asserts that no alteration can be discovered on dissection, in the digestive canal of persons who have swallowed any narcotic poison; and that if facts contrary to this assertion be met with in various authors, it is because there have been administered irritating substances capable of producing inflammation.^[429] The lungs, 394however, frequently exhibit morbid phenomena; their colour is sometimes violet, and frequently a deeper red than in the natural state. Their texture is also more dense, and less crepitating; and they are marked by livid spots. The blood contained in the ventricles of the heart, and in the veins, is said to be found in a liquid state; but Orfila advances a diametrically opposite opinion, and asserts that it is frequently coagulated. The brain and its membranes often exhibit a state of vascular congestion; in the case recorded by Mr. Stanley, in the sixth volume of the Transactions of the College of Physicians, the cellular tissue of the pia mater was found to contain water.^[430]

Of the detection of Opium.

There is no mode of identifying opium, whether in a liquid or solid form, so satisfactory as that which is at once afforded by its powerful and highly characteristic odour. In fatal instances, we shall always meet with it in the contents of the alimentary canal, and in such quantities as will leave no doubt as to its nature. The chemist may also proceed to a farther examination, by obtaining morphia from its solution, by a process which we have already described under the chemical history of opium.

395

Black Henbane. Hyoscyamus Niger. (Pentandria Monogynia. Nat. Ord. Luridæ Linn. Solaneæ Juss.)

Henbane is an indigenous annual, frequent on waste grounds, and at the sides of roads, particularly on a calcareous soil, flowering in July. The whole of the plant is poisonous when eaten; and in the recent state the odour of the leaves occasions stupor and delirium. The root of this plant when in full vegetation is very powerful; and there are several cases on record, where it has been eaten in mistake for parsnips,^[431] which it strongly resembles in its sweet and agreeable flavour. Its operation is very analogous to that of opium; producing sickness, stupor, delirium, and coma, with dilation of the pupils.

The pulse, at first hard, gradually becomes weak and tremulous; petechiæ frequently make their appearance, and death ensues. Late experiments have shewn that a peculiar alkaline body constitutes the active principle of this plant, and it has accordingly received, from its discoverers MM. Meissner and Brandes, the name of Hyoscyama.

Boerhaave experienced a trembling and drunkenness, in consequence of having prepared a plaister, into whose composition henbane entered as an ingredient; and the experiments of M. Orfila have shewn that it acts nearly in the same manner, whether applied upon the cellular texture, introduced into the stomach, or injected into the veins. Hence it follows that the active principle of this plant is carried into the circulation, and exerts a remarkable action on 396the brain and nervous system, producing an extraordinary state of delirium, which is succeeded by stupefaction. The physician will never probably be called upon to investigate a case of wilful poisoning by this narcotic; and should he be summoned to attend a person who, through mistake or accident, had swallowed it, we can hardly anticipate any peculiar mystery which requires elucidation.

There are several other species of henbane, as hyos. alb. aureus, physaloides, all of which are poisonous, although not in the same degree as the hyoscyamus niger, whose history we have just considered.

Prussic Acid. Hydro-cyanic Acid.

The Laurel (Prunus lauro-cerasus) and its distilled water. Bitter Almonds, and their essential oil.

Hydro-cyanic acid exists in a great variety of native combinations in the vegetable kingdom, and imparts to them peculiar qualities, which have been long known. It is, however, only within a few years, that this singular body has been obtained in its separate and independent form^[432]; indeed it was not until the publication of the celebrated memoir of Gay-Lussac upon this subject, in the year 1815, that its chemical composition was fully understood. In this memoir, it was clearly shewn to consist of a peculiar, gaseous, and highly inflammable compound of carbon and nitrogen, to which the name of cyanogene has been assigned, and hydrogen; the latter 397body acting as the acidifying principle; whence the term hydro-cyanic acid is very happily contrived to express its composition.

When obtained in its most concentrated form, by the process of M. Gay Lussac,^[433] it has the following characteristic properties, viz. At ordinary temperatures, it is liquid, colourless, and transparent; possessing an extremely powerful odour, very analogous to that of the blossom of the peach, or bitter almond tree; its taste is, at first, bland and sweetish, but afterwards pungent, bitter, and peculiar. Its extreme volatility is such, that when a drop of it is exposed to the air, on the end of a glass rod, it is rapidly crystallized. The same phenomenon takes place, if a drop be suffered to fall on a sheet of paper. Its specific gravity is ·7055; but, when in a concrete form it is only ·9, while that of its vapour is ·947. If inhaled, it produces almost immediate pain in the head, with deafness, unless very largely diluted with air or water.^[434] It is decomposed by a high temperature; and by the action even of light it is, in the course of a very short time, resolved into carbonic acid, ammonia, and carburetted hydrogen, a carbonaceous matter remaining behind.^[435] When brought near a body in a state of combustion, it instantly inflames and burns with a blue light. In water it is sparingly soluble; alcohol dissolves it copiously.

398The “medicinal Prussic acid,” as it has been called, as being the preparation lately introduced into medicine,^[436] differs only from that we have just described, in its degree of concentration. It is, in fact, the Prussic acid of Scheele, and may be considered as equivalent to the preparation of Gay-Lussac diluted with six times its volume, or eight times and a half its weight, of distilled water.

The hydro-cyanic acid has been discovered, in a state of perfect formation, in a variety of vegetables, whose peculiar odour at once announces its presence; such are bitter almonds; the kernels of apricots, cherries, particularly the Cerasa Juliana, and several plums; the leaves of laurel; and peach blossoms; and the bark of the prunus padus, or bird-cherry tree. The only mineral substance, in which hydro-cyanic has yet been detected is the Fer Azuré of Hauy.^[437] Animal substances, although they do not contain it ready formed, yet, when treated with an alkali at a high temperature, they yield it in great abundance, in consequence of the combination of its elements.

Action of hydro-cyanic Acid as a Poison.

The experiments which have been instituted with a view to ascertain the exact effects of this substance upon animal life, very clearly prove that the acid of Gay-Lussac is one of the most active poisons in nature; and that the various vegetable bodies, into whose composition it enters, exert an energy, corresponding 399with the quantity of this constituent, and the degree of concentration, in which it exists. The experiments of M. Orfila were made with Prussic acid, prepared according to the process of Scheele, and consequently containing a great proportion of water, as we have already explained; and yet the effects which followed its administration were extremely energetic. From the Annales de Chimie, for October 1814, we learn that a professor of chemistry, having inadvertently left on his table a phial filled with a solution of Prussic acid in alcohol, a female servant, who had been seduced by its agreeable smell, drank a small glass-full of it, and fell dead at the end of a few minutes, as if struck by apoplexy.

The following case is quoted by Dr. Granville, from Hufeland. D. L. a robust and healthy man, aged 36 years, while about to be seized as a thief by the police officers, snatched a small sealed phial from his pocket, broke off the neck of it, and swallowed the greatest part of its contents. A strong smell of bitter almonds soon spread around, which almost stupefied all present. The culprit staggered a few steps; then, without a groan, fell on his knees, and sunk lifeless down to the ground. Medical assistance being called in, not the slightest trace of pulse or breathing could be found. A few minutes afterwards, a single and violent expiration occurred, which was again repeated in about two minutes. The extremities were perfectly cold, the breast and abdomen still warm, the eyes half open and shining, clear, lively, full, almost projecting, and as brilliant as those of the most ardent youth under violent emotion. The face was neither distorted nor convulsed, but bore the image of quiet sleep. The corpse exaled a strong smell of bitter almonds, and the remaining liquid, 400being analysed, was found to be a concentrated solution of Prussic acid in alcohol. Cases also stand recorded where, from imprudent exposure to the vapours of the Prussic acid, persons have exhibited all the appearances of being poisoned. Some writers assert that Scheele himself, who died suddenly, while engaged in some inquiries into the nature and formation of this acid, was affected by its deleterious qualities. Orfila relates that Scharinger, Professor at Vienna, prepared some pure concentrated Prussic acid, and having diffused a certain quantity of it upon his naked arm, he died a short time afterwards. The professor, however, did not die in consequence of this accident; it appears, upon inquiry, that he was seized with apoplexy while sitting in a coffee house in the evening.

The distilled water of the cherry laurel^[438] has been proved, by numerous awful examples, to be a most energetic poison; and from the fatal effects to which the officinal preparation of it gave rise, it was early expunged from the Pharmacopœia of the London College. In the Philosophical Transactions for the year 1731, we shall find the history of its effects upon a woman of the name of Boyce, who, with a view to disprove an allegation, that one Mary Whaley had died in consequence of drinking a small quantity of laurel water, swallowed three spoonsful, and, afterwards, two more of the same liquid; after which she died in a very short time, without making the least complaint, and without any convulsion.

Foderé informs us that during the period he was pursuing his studies at Turin in 1784, the chambermaid 401and man servant of a noble family of that town, for the purpose of regaling themselves, stole from their master a bottle of distilled laurel water; fearful of being surprised, they hastily swallowed several mouthsful of it; but they soon paid the price of their dishonesty, having almost instantly expired in convulsions. Works on Toxicology also abound with the relation of experiments, made by numerous physiologists on different animals, with this deleterious liquid. Amongst the experimentalists we may enumerate the names of Madden, Mortimer, Browne, Langrish, Nicholls, Stenzelius, Heberden, Watson, Vater, Rattrai, the Abbé Rozier, Duhamel, Fontana, and Orfila. In this country we have had several fatal cases of poisoning by laurel water. In the year 1782, Dr. Price, of Guildford, having professed to have converted mercury into gold, offered to repeat his experiments before a competent tribunal, but the unfortunate philosopher put a period to his existence before the day appointed for his exhibition, by a draught of laurel water; a mode of death which had been, no doubt, suggested by the celebrated trial of Donellan, for the murder of Sir Theodosius Boughton, that had taken place in the preceding year, and left a strong impression upon the public mind; and whose details, it has been justly observed, are not more important from the elucidation of the effects of this poison, than from the strange display of professional testimony to which it gave origin, (see Appendix, page 243.) There are those who still profess to believe that the prisoner was unjustly convicted upon that occasion; Dr. Male states, without the least reserve, that it was neither proved that the deceased was poisoned, nor that any poison had 402existed.^[439] We feel no difficulty in declaring that we hold a directly opposite opinion; and we consider that many of the weaker points of professional evidence delivered on the trial, have received powerful support and elucidation from the experiments and observations of later physicians.

Nor are the leaves of this plant wholly free from danger; it is true that they have, for many years, been in general use among cooks, to communicate an almond or kernel-like flavour to custards, puddings, creams, blanc-mange, and other delicacies of the table; but the custom has not always been harmless; a fact with which it behoves the forensic physician to be acquainted. In some parts of the continent milk is boiled with one or two leaves of the cherry-laurel in it, and Ingenhouz states that he saw people much affected by it. In the Literary Chronicle (no. xxii, p. 348, 1819) we find the following illustrative case: “Several children at a boarding-school, in the vicinity of Richmond, having partaken of some custard flavoured with the leaves of the cherry-laurel, four of them were taken severely ill in consequence. Two of them, a girl of six, and a boy of five years of age, fell into a profound sleep, out of which they could not be roused for ten hours, the other two complained of severe pains in the epigastric region. By proper medical treatment, they all recovered, after an illness of three days.”

The essential oil of bitter almonds is equally poisonous; and the water distilled from them is highly 403dangerous if incautiously taken. Duvignau and Parent instituted some experiments upon themselves to ascertain this fact; they commenced by taking six drops of the water distilled three times, in an appropriate vehicle, without producing any other than a transient impression. On taking eighteen drops, however, vertigo was experienced, and a disposition to sleep, accompanied with a tingling of the ears and dimness of sight. When the dose was increased to twenty-two drops, alarming symptoms followed, such as convulsions, and vomiting; which, although the experimenters succeeded in allaying by antispasmodics, cured them completely of any ulterior wish to ascertain how far this substance might be deleterious. A drachm of the distilled water of bitter almonds has killed a moderate sized dog. The essential oil is proportionally more active; Mr. Brodie^[440] found that one drop, when applied to the tongue of a cat, killed it in five minutes; no sooner did the poison come in contact with the organ than the animal was seized with convulsions. When two drops of the same oil were injected with half an ounce of water into the rectum of a cat, it was not seized for two minutes, but it died, as in the former experiment, after the expiration of five minutes. While engaged in this inquiry, Mr. Brodie dipped the blunt end of a probe into the essential oil, and applied it to his tongue, with the intention of tasting it, and not having the least suspicion that so small a quantity could produce any of its specific effects on the nervous system; but scarcely had he applied it, when he experienced a very remarkable and unpleasant sensation, 404which he referred chiefly to the epigastric region, but the exact nature of which he could not describe, because he knew nothing similar to it. At the same time there was a sense of weakness in his limbs, as if he had not the command of his muscles; and he thought that he should have fallen. The fascinating liqueur noyau, créme de noyau, is indebted for its flavour to the essential oil of the bitter almond, or peach; and is undoubtedly deleterious if taken in excess. In the Journal des Debats, for 1814, we find that the late Duke Charles de Lorraine had nearly lost his life from swallowing some drops of eau de noyau too strongly impregnated with the essential oil of peach kernels.