Chapter XLIX: Part IX: Inorganic Poisons (7)

=Compound Pill of Subchloride of Mercury.=--Calomel and sulphurated antimony, each 1 ounce, guiac resin 2 ounces, castor-oil 1 fluid ounce. One grain (·0648 grm.) of calomel, and the same quantity of antimony sulphide, are contained in every 5 grains (324 mgrms.) of the pill mass, _i.e._, calomel 20 per cent.

=Ointment of Subchloride of Mercury= (=Unguentum hydrargyri subchloridi=).--Calomel mixed with benzoated lard; strength about 1 : 6½.

=White Precipitate= (=Hydrargyrum ammoniatum=, NH₂HgCl).--A white, heavy powder, subliming by heat without residue, and insoluble in water, alcohol, and ether. With soda, it yields a metallic sublimate. When boiled with potash, ammonia is evolved, the yellow oxide of mercury formed, and chloride of potassium passes into solution. It should contain 79·5 per cent. of mercury.

The fusible white precipitate of the pharmacopœia of the Netherlands does not appear to be of constant composition, varying between 69·4 to 65·6 per cent. of mercury.[904] It melts on heating, and leaves as a residue chloride of sodium.

[904] Hirsch, _Die Prüfung der Arzeneimittel_.

Commercial white precipitate is frequently adulterated; Barnes has found carbonates of lead and lime, the latter to the extent of nearly 2 per cent.[905] Calomel, according to Nickles,[906] has been substituted for white precipitate, but this was several years ago. The methods for detection are obvious.

[905] _Proceed. Brit. Pharm. Conf._, 1867, p. 10.

[906] _Journ. Pharm. et Chim._, le Série, 1858, vol. viij. p. 399.

=Ointment of Ammoniated Mercury= (=Unguentum hydrargyri ammoniati=).--1 part of ammoniated mercury mixed with 9 parts of simple ointment.

=Red Iodide of Mercury= (=Hydrargyrum iodidum rubrum=, HgI₂).--A crystalline powder of a scarlet colour, becoming yellow on gentle heating. It is very insoluble in water, one part requiring from 6000 to 7000 parts; soluble in 130 parts of cold, 150 of hot alcohol; and dissolving freely in ether, or in aqueous solution of iodide of potassium.

=Ointment of Red Iodide of Mercury= (=Unguentum hydrargyri iodidi rubri=).--16 grains of the substance mixed with an ounce of simple ointment.

=Green Iodide of Mercury= (=Hydrargyri iodidum viride=, HgI).--A dingy, greenish-yellow powder, darkening on exposure to light, and easily decomposed into the red iodide.

=Red Oxide of Mercury= (=Hydrargyri oxidum rubrum=), HgO = 216; Hg, 92·12 per cent.; specific gravity, 11 to 11·3; small, red, shining, crystalline scales, very insoluble in water, requiring about 20,000 parts; entirely soluble in hydrochloric acid. By a heat below redness it may be volatilised, and at the same time decomposed into mercury and oxygen. Its principal impurity is nitric acid, readily detected by the usual tests, or by heating in a test-tube, when, if nitric acid is present, orange vapours will be evolved. Fixed red powders (such as brick-dust and minium) are detected by being left as a residue, after the application of heat sufficient to volatilise the mercury. An ointment (strength 1 : 8) is officinal.

=Sulphate of Mercury.=--A white crystalline powder, decomposed by water into the very insoluble basic salt of mercury, known as _Turbith mineral_, HgSO₄2HgO.

=Turbith, or Turpeth, Mineral= is contained in the French pharmacopœia, HgSO₄2HgO; Hg, 82·4 per cent.; specific gravity, 8·319. It requires for solution 2000 parts of cold, and 600 of boiling water; but dissolves with tolerable ease in hydrochloric acid.

=The Sulphide of Mercury=, known in commerce under the name of _Ethiops mineral_, is officinal in France, the Netherlands, and Germany. Its properties have been already described. The German and Dutch pharmacopœias require in it 50, the French only 33⅓ per cent. of metallic mercury.

=Hahnemann’s Soluble Mercury= (=Hydrargyrum solubile Hahnemanni=) is officinal in the Dutch pharmacopœia. As found in commerce it contains metallic mercury, nitric acid, and ammonia. The mercury should be in the proportion of 86·33 per cent., the ammonia 2·44 per cent.

=Crystallised Nitrate of Mercury= (=Hydrargyrum nitricum oxidulatum=) is officinal in the pharmacopœias of Germany, Switzerland, and France. The salt is in white crystals, giving the reactions of nitric acid and mercury, decomposed by the addition of water, but fully soluble in water, if first moistened with nitric acid. The formula of the neutral salt is Hg2NO₃HgO2H₂O, which requires 69·4 per cent. of mercury. An acid solution of mercuric nitrate is officinal.

=An Ointment of Nitrate of Mercury= (=Unguentum hydrargyri nitratis=) (often called citrine ointment) is contained in the B.P.; it is made with 4 parts of mercury, nitric acid 12, lard 15, olive oil, 32; the strength is about 1 in 15½.

=A Chloride of Mercury and Quinine= exists in commerce, prepared by mixing 1 part of corrosive sublimate in solution with 3 parts of quinine chloride, evaporating, and crystallising.

=Cyanide of Mercury=, HgCy, is contained in the French pharmacopœia. It occurs in small, colourless, prismatic crystals, easily soluble in water. If to the solution chloride of tin be added, a black precipitate of reduced metal and stannous oxide is thrown down, and the odour of prussic acid is developed.

=Mercuric Sulphide= (=Sulphide of Mercury=, =Cinnabar=, =Vermilion=) is officinal in Germany, the Netherlands, and France; HgS = 232; specific gravity, solid, 8·2; Hg, 86·21 per cent., O, 13·79 per cent. For medicinal purposes it is made artificially. It is a beautiful red powder, insoluble in all alkaline and all acid liquids, with the exception of aqua regia. The solution gives the reactions of a sulphide and mercury. On heating, it must burn away entirely without residue; adulterations or impurities are--minium, lead, copper, and other metals. The detection of minium is conveniently executed in the dry way. Pure cinnabar, when heated in a matrass, gives a black sublimate, which becomes red on friction. If minium is present, sulphide of lead remains as a residue, and may be recognised on coal; the same remark applies to sulphide of antimony. If it be desired to take the percentage of mercury in cinnabar, equal parts of oxalate and cyanide of potassium should be well mixed with the cinnabar, and heated in the bent tube described at p. 654; by this means the whole of the metallic mercury is readily obtained.[907]

[907] Dr. Sutro has published a case (quoted by Taylor), in which the vapour of vermilion, applied externally, produced poisonous symptoms; yet, according to Polak, the Persians inhale it medicinally, smoking it with tobacco, catechu, mucilage, &c., the only bad effect being an occasional stomatitis.--Eulenberg, _Gewerbe Hygiene_, p. 741.

§ 831. =Mercury in the Arts.=--The use of mercury in the arts is so extensive, that any one in analytical practice is almost certain occasionally to meet with cases of accidental poisoning, either from the vapour[908] or some of its combinations.

[908] A singular case is cited by Tardieu (_Étude méd.-légal sur l’Empoisonnement_), in which a man, supposing he had some minerals containing gold, attempted the extraction by amalgamation with mercury. He used a portable furnace (for the purpose of volatilising the mercury) in a small room, and his wife, who assisted him, suffered from a very well-marked stomatitis and mercurial eruption.

Quicksilver is used in the extraction of gold, the silvering of mirrors, the construction of barometers, and various scientific instruments and appliances; also for the preservation of insects, and occasionally for their destruction.[909] An alloy with zinc and cadmium is employed by dentists for stopping teeth; but there is no evidence that it has been at all injurious, the mercury, probably, being in too powerful a state of combination to be attacked by the fluids in the mouth.[910] Cinnabar has also been employed to give a red colour to confections, and it may be found in tapers, cigarette papers, and other coloured articles. The nitrate of mercury in solution finds application in the colouring of horn, in the etching of metals, in the colouring of the finer sorts of wool, and in the hat manufacture.

[909] Forty-three persons were salivated from fumigating rooms with mercury for the purpose of destroying bugs (Sonnenschein’s _Handbuch_, p. 96).

[910] More danger is to be apprehended from the vulcanised rubber for artificial teeth; and, according to Dr. Taylor, accidents have occurred from the use of such supports or plates.

The sulphocyanide of mercury gives, when burnt, a most abundant ash, a fact utilised in the toy known as Pharaoh’s serpent; the products of combustion are mercurial vapours and sulphurous anhydride. That the substance itself is poisonous, is evident from the following experiment:--·5 grm. was given to a pigeon without immediate result; but ten hours afterwards it was indisposed, refused its food, and in forty hours died without convulsions.[911]

[911] Eulenberg, _Op. cit._, p. 472.

§ 832. The more Common Patent and Quack Medicines containing Mercury.

=Mordant’s Norton’s Drops.=--This patent medicine is a mixture of
the tincture of gentian and ginger, holding in solution a little
bichloride of mercury, and coloured with cochineal.

=Solomon’s Anti-impetigines= is a solution of bichloride of mercury,
flavoured and coloured.

=Poor Man’s Friend.=--An ointment of nitrate of mercury.

=Brown’s Lozenges.=--Each lozenge contains ½ grain of calomel, and
3½ grains of resinous extract of jalap; the rest is white sugar and
tragacanth.

=Ching’s Worm Lozenges.=--Each lozenge contains 1 grain of calomel;
the rest white sugar and tragacanth, with saffron as a colouring
matter.

=Storey’s Worm Cakes.=--Each cake 2 grains of calomel, 2 grains of
cinnabar, 6 grains of jalap, 5 grains of ginger, and the remainder
sugar and water.

=Wright’s Pearl Ointment= is said to be made up of 8 ozs. of white
precipitate rubbed to a cream in 1 pint of Goulard’s extract, and to
the mixture is added 7 lbs. of white wax and 10 lbs. of olive oil.

=Keyser’s Pills.=--The receipt for these pills is--red oxide of
mercury 1½ oz., distilled vinegar (dilute acetic acid) 1 pint;
dissolve, add to the resulting solution manna 2 lbs., and triturate
for a long time before the fire, until a proper consistence is
attained; lastly, divide the mass into pills of 1½ grain each.

=Mitchell’s Pills.=--Each pill contains aloes ·8 grain, rhubarb 1·6
grain, calomel ·16 grain, tartar emetic ·05 grain.

Many =Antibilious Pills= will be found to contain calomel, a few
mercury in a finely divided state.

§ 833. =Mercury in Veterinary Medicine.=--Farmers and farriers use the ointment (_blue ointment_) to a dangerous extent, as a dressing for the fly, and wholesale poisoning of sheep has been in several instances the consequence.[912] Ethiops mineral and Turpeth mineral are given to dogs when affected by the distemper, worms, or the mange. Mercury, however, is not very frequently given to cattle by veterinary surgeons, ruminants generally appearing rather susceptible to its poisonous effects.

[912] Twenty-five tons of blue ointment are said to have been sold to farmers by a druggist in Boston, Lincolnshire, in the course of a single year.--Taylor’s _Medical Jurisprudence_, vol. i. p. 279.

§ 834. =Medicinal and Fatal Dose--Horses.=--Cinnabar 14·2 grms, (½ oz.), calomel 14·2 grms. (½ oz.) or more, corrosive sublimate ·13 to ·38 grm. (2 to 6 grains), and as much as 1·3 grm. (20 grains) have been given in farcy.

=Cattle.=--Mercury with chalk 3·8 to 11·6 grms. (1 to 3 drms.), calomel 3·8 to 7·7 grms. (1 to 2 drms.) for worms; ·65 to 1·3 grm. (10 to 20 grains) as an alterative; Ethiops mineral, 7·7 to 15·5 grms. (2 to 4 drms.).

=Dogs.=--Ethiops or Turpeth mineral ·13 to 1·3 grm. (2 to 20 grains), according to the size.

=Fowls.=--Mercury and chalk are given in fractions of a grain.

=Hogs= are also treated with mercury and chalk; the dose usually given does not exceed ·32 grm. (5 grains).

It may be remarked that many of the doses quoted appear very large; the writer cannot but consider that 20 grains of corrosive sublimate administered to a horse would be more likely to kill the animal than to cure the disease.

=Man.=--Corrosive sublimate has been fatal in a dose so small as ·19 grm. (3 grains); white precipitate has caused dangerous symptoms in doses of from 1·9 to 2·6 grm. (30 to 40 grains); the cyanide of mercury has killed a person in a dose of ·64 grm. (10 grains)--_Christison_; and Turpeth mineral has proved fatal in doses of 2·6 grms. (40 grains).

Other preparations of mercury have also been fatal, but a doubt has existed as to the precise quantity. Sometimes, also, there is probably a chemical change in the substance, so that it is impossible to state the fatal dose. For example, it is well known that calomel, under the influence of alkaline chlorides, can be converted into the bichloride--a fact which probably explains the extensive corrosive lesions that have been found after death from large doses of calomel.

§ 835. =Poisoning by Mercury--Statistics.=--In the Registrar-General’s death returns for the ten years ending 1892, it appears that in England the deaths from mercurial poisoning[913] were 40 males, 19 females; of these, 16 males and 18 females were cases of suicide, the remainder were referred to accident.

[913] The deaths are registered under the term “_Mercury_,” but the majority are poisonings by “_Corrosive Sublimate_.”

The effects of the different compounds of mercury may be divided into two groups, viz., (1) Those caused by the finely divided metal and the non-corrosive compounds; (2) the effects caused by the corrosive compounds.

§ 836. (1) Effects of Mercurial Vapour, and of the Non-Corrosive Compounds of Mercury.

(_a_) =Vegetable Life.=--Priestly and Boussingault have shown that plants under a glass shade in which mercury is exposed in a saucer, first exhibit black spots on the leaves; ultimately, the latter blacken entirely, and the plants die.

(_b_) =Animal Life.=--Mercury in the form of vapour is fatal to animal life, but it is only so by repeated and intense application. Eulenberg[914] placed a rabbit under a large glass shade, and for four days exposed it daily for two hours to the volatilisation of 2 grms. of mercury on warm sand; on the sixth and seventh day 1·5 grm. was volatilised. On the fifteenth day there was no apparent change in the aspect of the animal; 5 grms. of mercury were then heated in a retort, and the vapour blown in at intervals of ten minutes. Fourteen days afterwards the gums were reddened and swollen, and the appetite lost; the conjunctivæ were also somewhat inflamed. The following day these symptoms disappeared, and the animal remained well.

[914] _Op. cit._, p. 728.

In another experiment 20 grms. of mercury were volatilised, and a rabbit exposed to the vapour under a small glass shade. The following day the conjunctivæ were moist and reddened; two days afterwards 10 grms. of mercury were volatilised in the same way; and in two days’ interval other 10 grms. were volatilised in three-quarters of an hour. There was no striking change noticeable in the condition of the animal, but within forty-eight hours it was found dead. The cause of death proved to be an extravasation of blood at the base of the brain. The bronchia were reddened throughout, and the lungs congested. Mercury, as with man, is also readily absorbed by the broken or unbroken skin; hence thousands of sheep have been poisoned by the excessive and ignorant external application of mercurial ointment as a remedy against the attacks of parasites. The sheep become emaciated, refuse food, and seem to be in pain, breathing with short quick gasps.

In experiments on rabbits, dogs, and warm-blooded animals generally, salivation and stomatitis are found to occur as regularly as in man; so also in animals and man, paralytic and other nervous affections have been recorded.

§ 837. (_c_) =Effects on Man.=--In 1810[915] an extraordinary accident produced, perhaps, the largest wholesale poisoning by mercurial vapour on record. The account of this is as follows:--H.M.S. “Triumph,” of seventy-four guns, arrived in the harbour of Cadiz in the month of February 1810; and in the following March, a Spanish vessel, laden with mercury for the South American mines, having been driven on shore in a gale, was wrecked. The “Triumph” saved by her boats 130 tons of the mercury, and this was stowed on board. The mercury was first confined in bladders, the bladders again were enclosed in small barrels, and the barrels in boxes. The heat of the weather, however, was at this time considerable; and the bladders, having been wetted in the removal from the wreck, soon rotted, and mercury, to the amount of several tons, was speedily diffused as vapour through the ship, mixing more or less with the bread and the other provisions. In three weeks 200 men were affected with ptyalism, ulceration of the mouth, partial paralysis, and, in many instances, with diarrhœa. The “Triumph” was now ordered to Gibraltar, the provisions were removed, and efforts were made to cleanse the vessel. On restowing the hold, every man so employed was salivated. The effects noted were not confined to the officers and ship’s company, for almost all the stock died from the fumes--mice, cats, a dog, and even a canary bird shared the same fate, though the food of the latter was kept in a bottle closely corked up. The vapour was very deleterious to those having any tendency to pulmonic affections. Three men, who had never complained before they were saturated with mercury, died of phthisis; one, who had not had any pulmonic complaint, was left behind at Gibraltar, where his illness developed into a confirmed phthisis. Two died from gangrene of the cheeks and tongue. A woman, confined to bed with a fractured limb, lost two of her teeth; and many exfoliations of the jaw took place.

[915] “An Account of the Effect of Mercurial Vapours on the Crew of His Majesty’s Ship ‘Triumph,’ in the year 1810.”--_Phil. Trans._, 113, 1823.

Accidents from the vapour of mercury, quite independently of its applications in the arts, have also occurred, some of them under curious circumstances; such, for example, is the case mentioned in the footnote to p. 639. Witness, again, a case mentioned by Seidel,[916] in which a female, on the advice of an old woman, inhaled for some affection or other 2·5 grms. of mercury poured on red-hot coals, and died in ten days with all the symptoms of mercurial poisoning.

[916] Maschka’s _Handbuch_, Bd. ii. 295.

The metal taken in bulk into the stomach has been considered non-poisonous, and, probably, when perfectly pure, it is so; we have, however, the case of a girl who swallowed 4½ ozs. by weight of the liquid metal, for the purpose of procuring abortion--this it did not effect; but, in a few days, she suffered from a trembling and shaking of the body and loss of muscular power. These symptoms continued for two months, but there was no salivation and no blue marks on the gums. This case is a rare one, and a pound or more has been taken without injury.

§ 838. =Absorption of Mercury by the Skin.=--Mercury in a finely divided form, rubbed into the skin, is absorbed, and all the effects of mercurialism result. This method of administering mercury for medicinal purposes has long been in use, but, when the inunction is excessive, death may occur. Thus, Leiblinger records a case in which three persons were found dead in bed; the day before they had rubbed into the body, for the purpose of curing the itch, a salve containing 270 grms. of mercury finely divided.

It is difficult to say in what proportion workers in mercury, such as water-gilders, &c., suffer. According to Hirt, not only do 1·5 to 2·1 per cent. of the workmen employed in smelting mercury ores suffer acutely, but as high a proportion as 8·7 per cent. are slightly affected.

§ 839. =Symptoms of Poisoning by Mercury Vapour.=--The symptoms of poisoning by mercury vapour, or by the finely divided metal, are the same as those which arise from the corrosive salts, with the exception of the local action. In mild cases there is pallor, languor, and sore mouth (from slightly inflamed gums), fœtid breath, and disorder of the digestive organs. If the action is more intense, there is an inflammation of the gums and, indeed, of the whole mouth, and salivation, which is sometimes so profuse that as much as two gallons of saliva have been secreted daily. The saliva is alkaline, has a bad odour, and its specific gravity in the early stages is increased, but ultimately becomes normal; the gums are raised into slight swellings, which gradually enlarge and coalesce. The teeth that are already carious, decay more rapidly; they become loose, and some may be shed; the inflammatory action may extend to the jaw, and necrosis of portions of the bone is no unusual occurrence. On recovery, the cheeks sometimes form adhesions with the gums, and cicatrices always mark the loss of substance which such an affection entails. With the stomatitis there are disturbances of the gastro-intestinal tract--nausea and vomiting, pain in the stomach, and diarrhœa alternating with constipation. Conjunctivitis is very common, both in man and animals, from exposure to mercury vapours. The further action of the metal is shown in its profound effects on the nervous system. The patient is changed in his disposition, he is excitable, nervous, or torpid; there are sleeplessness and bad dreams, at the same time headache, noises in the ears, giddiness, faintings, &c.

§ 840. =Mercurial Tremor.=--Mercurial tremor[917] may follow, or accompany the above state, or it may be the chief and most prominent effect. It specially affects the arms, partly withdrawing the muscles from the control of the will, so that a person affected with mercurial tremor is incapacitated for following any occupation, especially those requiring a delicate and steady touch. In cases seriously affected, the tremor spreads gradually to the feet and legs, and finally the whole body may be invaded. The patient is no longer master of his muscles--the muscular system is in anarchy, each muscle aimlessly contracting and relaxing independently of the rest--the movement of the legs becomes uncertain, the speech stuttering, the facial expressions are even distorted into grimaces, and the sufferer sinks into a piteous state of helplessness. The convulsive movements generally cease during sleep. The tremors are accompanied by interference with the functions of other organs: the respiration is weakened and difficult; dyspnœa, or an asthmatic condition, results; the pulse is small and slow; paresis, deepening into paralysis of the extremities, or of a group of muscles, follows; and, lastly, if the condition is not alleviated, the patient becomes much emaciated and sinks from exhaustion. Pregnant women are liable to abortion, and the living infants of women suffering from tremor have also exhibited tremor of the limbs.

[917] A case of mercurial tremor (in _Bericht. des K. K. Allgem. Krankenhauses zu Wien im Jahre 1872_, Wien, 1873) is interesting, as showing the influence of pregnancy. A woman, twenty years of age, employed in making barometers, had, in 1869, mercurial tremor and salivation. During a three months’ pregnancy the tremor ceased, but again appeared after she had aborted. She again became pregnant, and the tremor ceased until after her confinement in November 1871. The tremor was so violent that the patient could not walk; she also had stomatitis; but ultimately, by treatment with galvanism and other remedies, she recovered.

In the case of the “mass poisoning” on board the “Triumph,” it has been mentioned that several of the sailors became consumptive, and the same effect has been noticed among all workers in the metal; it is now, indeed, an accepted fact that the cachexia induced by mercurialismus produces a weak habit of body specially liable to the tuberculous infection.

The course of the poisoning is generally more rapid when it has resulted from the taking of mercury internally as a medicine than when inhaled by workers in the metal, _e.g._, a patient suffering from mercurial tremor shown to the Medical Society by Mr. Spencer Watson in 1872, had resisted for seven years the influence of the fumes of mercury; and then succumbed, exhibiting the usual symptoms. Idiosyncrasy plays a considerable _rôle_; some persons (and especially those whose kidneys are diseased) bear small doses of mercury ill, and are readily salivated or affected; this is evidently due to imperfect elimination.

§ 841. =Mercuric Methide=, Hg(CH₃)₂.--This compound is obtained by the action of methyl iodide on sodium amalgam in the presence of acetic ether. It is a dense, stable liquid, of highly poisonous properties. In 1865, mercuric methide, in course of preparation in a London laboratory, caused two cases of very serious slow poisoning.[918] One was that of a German, aged 30, who was engaged in preparing this compound for three months, and during this time his sight and hearing became impaired; he was very weak, his gums were sore, and he was ultimately admitted into St. Bartholomew’s Hospital, February 3rd, 1865. His urine was found to be albuminous, and his mental faculties very torpid. On the 9th he became noisy, and had to be put under mechanical restraint. On the 10th he was semi-comatose, but there was no paralysis; his breath was very offensive, his pupils dilated; at intervals he raised himself and uttered incoherent howls. There was neither sensation nor motion in the left leg, which was extended rigidly; the knee and the foot were turned slightly inward. On the 14th he died insensible.

[918] _St. Barth. Hosp. Reports_, vol. i., 1866, p. 141.

The only appearance of note seen at the autopsy was a congestion of the grey matter in the brain; the kidneys and liver were also congested, and there were ecchymoses in the kidneys.

The second case--a young man, aged 23, working in the same laboratory--was admitted into the hospital, March 28th, 1865. In the previous January he had been exposed to the vapour of mercuric methide for about a fortnight; during the illness of the other assistant he felt ill and weak, and complained of soreness of the gums and looseness of the teeth. He had also dimness of vision, pain and redness of the eyes, giddiness, nausea and vomiting, the ejected matters being greenish and watery. At the beginning of March his sight and taste became imperfect--all things tasted alike; his tongue was numb and his gums sore, he was also salivated slightly. A week before admission he lost his hearing, and first his hands and then his feet became numb; on admission his breath was very offensive, his pupils dilated; the sight impaired; he was very deaf, and his powers of speech, taste, and smell were deficient. There was anæsthesia of the body, and the movement of the limbs was sluggish and difficult. He continued in the hospital for nearly a month, with but little change. On April 24th, it was noticed that he was getting thinner and slightly jaundiced; he moved his arms aimlessly in an idiotic manner, and passed his urine involuntarily. On April 27th he was more restless, and even violent, shrieking out and making a loud, incoherent noise, or laughing foolishly; he passed his motions and urine beneath him. On July 7th he was in a similar state--perfectly idiotic. He died on April 7th, 1866, about a year and three months from his first exposure to the vapour; the immediate cause of death was pneumonia. The _post-mortem_ appearances of the brain and membranes differed little from the normal state; the grey matter was pink, but otherwise healthy; there was a considerable amount of cerebro-spinal fluid; the arachnoid along the longitudinal fissure was thickened; the total weight of the brain with medulla was 41 ozs. The stomach was of enormous size; the pyramids of the kidneys were congested, as was also the small intestine; the lungs showed the usual signs of pneumonia.[919]

[919] _St. Barth. Hosp. Reports_, vol. ii. p. 211.

§ 842. =Effects of the Corrosive Salts of Mercury.=--The type of the corrosive salts is mercuric chloride, or corrosive sublimate--a compound which acts violently when administered, either externally or internally, in large doses.[920] If the poison has been swallowed, the symptoms come on almost immediately, and always within the first half hour; the whole duration also is rapid. In 36 cases collected by F. A. Falck, 11 died on the first or second day, and 11 on the fifth day; so that 61 per cent. died in five days--the remainder lived from six to twenty-six days. The shortest fatal case on record is one communicated to Dr. Taylor by Mr. Welch; in this instance the man died from an unknown quantity within half an hour.

[920] The effects on animals are similar to those on man. Richard Mead gave a dog with bread 3·8 grms. (60 grains) of corrosive sublimate:--“Within a quarter of an hour he fell into terrible convulsions, casting up frequently a viscid frothy mucus, every time more and more bloody, till, tired and spent with this hard service, he lay down quietly, as it were, to sleep, but died the next morning.”

In the very act of swallowing, a strong metallic taste and a painful sensation of constriction in the throat are experienced. There is a burning heat in the throat extending downwards to the stomach. All the mucous membranes with which the solution comes in contact are attacked, shrivelled, and whitened; so that, on looking into the mouth, the appearance has been described as similar to that produced by the recent application of silver nitrate. The local changes may be so intense as to cause œdema of the glottis, and death through asphyxia. In a few minutes violent pain is felt in the stomach; so much so, that the sufferer is drawn together, and is in a fainting condition; but there are rare cases in which pain has been absent. There are nausea and vomiting, the ejected matters being often streaked with blood; after the vomiting there is purging; here also the motions are frequently bloody.[921] The temperature of the body sinks, the respiration is difficult, and the pulse small, frequent, and irregular. The urine is generally scanty, and sometimes completely suppressed.[922] Sometimes there is profuse hæmorrhage from the bowel, stomach, or other mucous membrane, and such cases are accompanied by a considerable diminution of temperature. In a case recorded by Lœwy,[923] after a loss of blood by vomiting and diarrhœa, the temperature sank to 33·4°. The patient dies in a state of collapse, or insensibility, and death is often preceded by convulsions.

[921] The mixture of blood with the evacuations is more constantly observed in poisoning by corrosive sublimate than in poisoning by arsenic, copper, or lead.

[922] In a case recorded by Dr. Wegeler (Casper’s _Wochenschrift_, January 10, 1846, p. 30), a youth, aged 17, swallowed 11·6 grms. (3 drachms) of the poison. No pain was experienced on pressure of the abdomen; he died on the sixth day, and during the last three days of life no urine was secreted.

[923] _Vierteljahrsschr. für ger. Med._, 1864, vol. i. p. 187.

§ 843. Two remarkable cases of death from the external use of corrosive sublimate are recorded by Anderseck. An ointment, containing corrosive sublimate, was rubbed into the skin of two girls, servants, in order to cure the itch. The one, during the inunction, complained of a burning of the skin; the other also, a little while after, suffered in the same way. During the night the skin of each swelled, reddened, and became acutely painful. There were thirst and vomiting, but no diarrhœa, On the following day there was an eruption of blebs or little blisters. On the third day they had diarrhœa, tenesmus, fever, and diminution of the renal secretion; on the fourth day, fœtid breath, stomatitis, hyperæsthesia of the body, and a feeling of “pins and needles” in the hands and feet were noted. The first girl died in the middle of the fifth day, fully conscious; the other died on the sixth. So also Taylor[924] gives the case of a girl, aged 9, who died from the effects of an alcoholic solution of corrosive sublimate (strength, 80 grains to the oz.) applied to the scalp as a remedy for ringworm. The same author[925] further quotes the case of two brothers who died--the one on the fifth, the other on the eleventh day--from the effects of absorbing corrosive sublimate through the unbroken skin.

[924] _Op. cit._

[925] _Poisons_, 1848, p. 394.

§ 844. =The Nitrates of Mercury= are poisons, but little (if at all) inferior in corrosive action to mercuric chloride. Death has resulted from both the external and internal use. Application of the nitrate as an escharotic to the _os uteri_, in one case,[926] produced all the symptoms of mercurial poisoning, but the woman recovered; in another case,[927] its use as a liniment caused death.

[926] _Med. Gazette_, vol. 45, p. 1025.

[927] _Edin. Monthly Journal_, 1864, p. 167.

§ 845. When taken internally, the symptoms are scarcely different from those produced by corrosive sublimate. It seems an unlikely vehicle for criminal poisoning, yet, in the case of _Reg._ v. _E. Smith_ (Leicester Summer Assizes, 1857), a girl was proved to have put a solution of nitrate of mercury in some chamomile tea, which had been prescribed for the prosecutrix. The nauseous taste prevented a fatal dose being taken; but the symptoms were serious.

§ 846. =Mercuric Cyanide= acts in a manner very similar to that of corrosive sublimate, 1·3 grm. (about 20 grains) in one case,[928] and in another[929] half the quantity, having destroyed life.

[928] Orfila, i. p. 735.

[929] Christison, p. 427.

§ 847. =White Precipitate= (ammoniated mercury), as a poison, is weak. Out of fourteen cases collected by Taylor, two only proved fatal; one of these formed the subject of a trial for murder, _Reg._ v. _Moore_ (Lewes Lent Assizes, 1860). The effects produced are vomiting, purging, &c., as in corrosive sublimate.[930] Other preparations of mercury, such as the red iodide, the persulphide, and even calomel,[931] have all a more or less intense poisonous action, and have caused serious symptoms and death.

[930] See Dr. Th. Stevenson, “Poisoning by White Precipitate,” _Guy’s Hospital Reports_, vol. xix. p. 415.

[931] Seidel quotes a case from Hasselt, in which a father, for the purpose of obtaining insurance money, killed his child by calomel.

§ 848. =Treatment of Acute and Chronic Poisoning.=--In acute poisoning, vomiting usually throws off some of the poison, if it has been swallowed; and the best treatment seems to be, to give copious albuminous drinks, such, for example, as the whites of eggs in water, milk, and the like. The vomiting may be encouraged by subcutaneous injections of apomorphine. The after-treatment should be directed to eliminating the poison, which is most safely effected by very copious drinks of distilled water (see “Appendix”).

The treatment of slow poisoning is mainly symptomatic; medicinal doses of zinc phosphide seem to have done good in mercurial tremors. Potassic iodide is also supposed to assist the elimination of mercury.

§ 849. =Post-mortem Appearances.=--The pathological effects seen after chronic poisoning are too various to be distinctive. In the museum of the Royal College of Surgeons there is (No. 2559) the portion of a colon derived from a lady aged 74.[932] This lady had been accustomed for forty-three years to take a grain of calomel every night; for many years she did not suffer in health, but ultimately she became emaciated and cachectic, with anasarca and albuminuria. The kidneys were found to be granular, and the mucous membrane of a great part of the intestine of a remarkable black colour, mottled with patches of a lighter hue, presenting somewhat the appearance of a toad’s back. From the portion of colon preserved mercury was readily obtained by means of Reinsch’s test. The black deposit is in the submucosa, and it is, without doubt, mercurial, and probably mercury sulphide. In acute poisoning (especially by the corrosive salts) the changes are great and striking. After rapid death from corrosive sublimate, the escharotic whitening of the mouth, throat, and gullet, already described, will be seen. The mucous membrane right throughout, from mouth to anus, is more or less affected and destroyed, according to the dose and concentration of the poison. The usual appearances in the stomach are those of intense congestion, with ecchymoses, and portions of it may be destroyed. Sometimes the coats are very much blackened; this is probably due to a coating of sulphide of mercury.

[932] _Path. Soc. Trans._, xviii. 111.

In St. George’s Hospital Museum (Ser. ix. 43, y. 337) there is a
stomach, rather large, with thickened mucous coats, and having on
the mucous surface a series of parallel black, or black-brown lines
of deposit; it was derived from a patient who died from taking
corrosive sublimate. With the severe changes mentioned, perforation
is rare.[933] In the intestines there are found hyperæmia,
extravasations, loosening of the mucous membrane, and other changes.
The action is particularly intense about the cæcum and sigmoid
flexure; in one case,[934] indeed, there was little inflammatory
redness of the stomach or of the greater portion of the intestine,
but the whole surface of the cæcum was of a deep black-red colour,
and there were patches of sloughing in the coats. The kidneys are
often swollen, congested, or inflamed; changes in the respiratory
organs are not constantly seen, but in a majority of the cases there
have been redness and swelling of the larynx, trachea, and bronchi,
and sometimes hepatisation of smaller or larger portions of the
lung.

[933] There is only one case of perforation on record.

[934] _Lancet_, 1845, p. 700.

In St. George’s Hospital Museum, there are (from a patient dying in
the hospital) preparations which well illustrate what pathological
changes may be expected in any case surviving for a few days. The
patient was Francis L----, aged 45, admitted to the hospital,
February 27, 1842. He took a quantity of corrosive sublimate spread
on bread and butter, was immediately sick, and was unable to take as
much as he had intended. The stomach-pump and other remedies were
used. On the following day his mouth was sore, and on March 1st his
vision was dim; his mouth was drawn over to the right side, and he
lost power over the left eyelid, but he had no pain; he passed some
blood from the bowel. On the 2nd he passed much blood, and was
salivated; still no pain. On March 4, on the evening of the sixth
day, he expired; he was drowsy during the last day, and passed
watery evacuations.

Prep. 14a, Ser. ix., shows the pharynx, œsophagus, and tongue; there
is ulceration of the tonsils, and fibrinous exudation on the gullet.
The stomach (43b, 199) shows a large dark slough, three inches from
the cardiac extremity; the margin surrounding the slough is
thickened, ulcerated, and irregular in shape, the submucous tissue,
to some extent, being also thickened; there is fibrine in the ileum,
pharynx, and part of the larynx. The action extended to the whole
intestine, the rectum in prep. 145a, 36, is seen to be thickened,
and has numerous patches of effused fibrine.

It is a curious fact that the external application of corrosive sublimate causes inflammatory changes in the alimentary canal of nearly the same intensity as if the poison had been swallowed. Thus, in the case of the two girls mentioned _ante_ (p. 647), there was found an intense inflammation of the stomach and intestines, the mucous tissues being scarlet-red, swollen, and with numerous extravasations.

§ 850. The effects of the nitrate of mercury are similar to the preceding; in the few cases which have been recorded, there has been intense redness, and inflammation of the stomach and intestines, with patches of ecchymosis. White precipitate, cyanide of mercury, mercuric iodide, and mercurous sulphide (turpeth-mineral) have all caused inflammation, more or less intense, of the intestinal tract.

§ 851. =Elimination of Mercury.=--The question of the channels by which mercury is eliminated is of the first importance. It would appear certain that it can exist in the body for some time in an inactive state, and then, from some change, be carried into the circulation and show its effects.[935] Voit considers that mercury combines with the albuminous bodies, separating upon their oxidation, and then becoming free and active.[936]

[935] Tuson gave a mare, first, 4 grains, and afterwards 5 grains of corrosive sublimate twice a day; at the end of fourteen days, in a pint of urine no mercury was detected, but at the end of three weeks it was found.

[936] _Voit, Physiol. chem. Unters._, Augsburg, 1857.

Ullmann[937] found most mercury in the following order:--Kidneys, liver, spleen, a small quantity in the stomach, no mercury in the small intestine, but some in the large intestine; small weighable quantities in the heart and skeletal muscles, also in the lungs; but no mercury, when the dose was small, in brain, the salivary glands, abdominal glands, thyroid glands, the bile, or the bones.

[937] _Chem. Centr._, 1892, ii. 941.

The main channel by which absorbed mercury passes out of the body is the kidneys, whilst mercurial compounds of small solubility are in great part excreted by the bowel. A. Bynssen,[938] after experimenting with mercuric chloride (giving ·015 to ·15 grm., with a little morphine hydrochlorate), came to the conclusion that it could be detected in the urine about two hours, and in the saliva about four hours, after its administration; he considered that the elimination was finished in twenty-four hours.

[938] _Journal de l’Anat. et de Physiol._, 1872, No. 5, p. 500. On the separation of mercury by the urine, see also Salkowsky in Virchow’s _Archiv_, 1866.

From the body of a hound that, in the course of thirty-one days, took 2·789 grms. of calomel (2·368 Hg) in eighty-seven doses, about 94 per cent. of the substance was recovered on analysis:--

Mercurous
Sulphide.
Grms.
In the fæces, 2·1175
„ urine, 0·0550
„ brain, heart, lungs, spleen, pancreas,
kidneys, scrotum, and penis, 0·0090
„ liver, 0·0140
„ muscles, 0·0114
------
2·2069

This equals 1·9 of metallic mercury.[939] Thus, of the whole 2·2 grms. of mercuric sulphide separated, over 95 per cent. was obtained from the fæces.

[939] Riederer, in Buchner’s _Neues Repert. f. Pharm._, Bd. xvii. 3, 257, 1868.

This case is of considerable interest, for there are recorded in toxicological treatises a few cases of undoubted mercurial poisoning in which no poison had been detected, although there was ample evidence that it had been administered by the mouth. In such cases, it is probable that the whole length of the intestinal canal had not been examined, and the analysis failed from this cause. When (as not unfrequently happens) the mercurial poison has entered by the skin, it is evident that the most likely localities are the urine, the liver, and the kidneys.[940]

[940] A woman died from the effects of a corrosive sublimate lotion applied by a quack to a wound in her leg. The writer found no poison in the stomach, but separated a milligramme of metallic mercury from the liver; the urine and intestines were not sent.

In a case related by Vidal,[941] the _Liquor Bellostii_ (or solution of mercuric nitrate) was ordered by mistake instead of a liniment. Although externally applied, it caused salivation, profuse diarrhœa, and death in nine days. The whole of the intestinal tract was found inflamed with extravasations, and mercury detected in the liver.

[941] _Gaz. des Hôp._, Juillet 1864.

In any case of external application, if death ensues directly from the poison, evidence of its presence will probably be found; but too much stress must not be laid upon the detection of mercury, for, as Dr. Taylor says, “Nothing is more common than to discover traces of mercury in the stomach, bowels, liver, kidneys, or other organs of a dead body.”[942]

[942] Taylor, _Medical Jurisprudence_, i. p. 288.

§ 852. =Tests for Mercury.=--Mercury, in combination and in the solid form, is most readily detected by mixing the substance intimately with dry anhydrous sodic carbonate, transferring the mixture to a glass tube, sealed at one end, and applying heat. If mercury be present, a ring of minute globules condenses in the cool part of the tube. If the quantity of mercury is likely to be very minute, it is best to modify the process by using a subliming cell (p. 258), and thus obtain the sublimate on a circle of thin glass in a convenient form for microscopical examination. If there is any doubt whether the globules are those of mercury or not, this may be resolved by putting a fragment of iodine on the lower disc of the subliming cell, and then completing it by the disc which contains the sublimate (of course, the supposed mercurial surface must be undermost); on placing the cell in a warm, light place, after a time the scarlet iodide is formed, and the identification is complete. Similarly, a glass tube containing an ill-defined metallic ring of mercury can be sealed or corked up with a crystal of iodine, and, after a few hours, the yellow iodide, changing to scarlet, will become apparent. There are few (if any) tests of greater delicacy than this.

Mercury in solution can be withdrawn by acidulating the liquid, and then inserting either simply a piece of gold foil, gold wire, or bright copper foil; or else, by a galvanic arrangement, such as iron wire wound round a gold coin, or gold foil attached to a rod of zinc; or, lastly, by the aid of gold or copper electrodes in connection with a battery. By any of these methods, mercury is obtained in the metallic state, and the metal with its film can be placed in a subliming cell, and globules deposited and identified, as before described.

The =Precipitating Reagents= for mercury are numerous: a solution of stannous chloride, heated with a solution of mercury, or any combination, whether soluble or insoluble, reduces it to the metallic state.

=Mercurous Salts= in solution yield, with potash, soda, or lime, a black precipitate of mercurous oxide. =Mercuric Salts=, a bright yellow precipitate of mercuric oxide.

=Mercurous Salts= yield black precipitates, with sulphides of ammonium and hydrogen. =Mercuric Salts= give a similar reaction, but, with sulphuretted hydrogen, first a whitish precipitate, passing slowly through red to black.

=Mercurous Salts=, with solutions of the chlorides, give a white precipitate of calomel; the =Mercuric Salts= yield no precipitate under similar circumstances. =Mercurous Salts=, treated with iodide of potassium, give a green mercurous iodide; =Mercuric=, a scarlet.

§ 853. =The Detection of Mercury in Organic Substances and Fluids.=--Ludwig’s process, previously described, is found in practice the best. Fluids, such as urine, must be evaporated to dryness, and then treated with hydrochloric acid. Such organs as the liver are cut up and boiled in 20 per cent. HCl. Distinct evidence of mercury in the liver has been obtained on a piece of copper gauze, in a case where a child had been given 2 grains of calomel before death. “Four ounces of the liver were treated with hydrochloric acid and water, and a small piece of pure copper placed in the acid liquid while warm, and kept there for about forty-eight hours. It acquired a slight silvery lustre, and globules of mercury were obtained from it by sublimation.”

To detect the cyanide of mercury may require special treatment, and Vitali[943] recommends the following process:--The fluid is acidified with tartaric acid and neutralised by freshly precipitated CaCO₃; a slight excess of hydric sulphide is added, and the flask allowed to rest for twenty-four hours in the cold. Then a further quantity of SH₂ is added, and a current of hydrogen passed through the liquid; the effluent gas is first made to bubble through a solution of bismuth nitrate in dilute nitric acid (for the purpose of absorbing SH₂), and then through aqueous potash (to absorb HCl); in the first flask the analyst will separate and identify mercury sulphide, while in the last flask there will be potassic cyanide, which will respond to the usual tests.

[943] _L’Orosi_, xii. 181-196.

In those cases where no special search is made for mercury, but an acid (hydrochloric) solution is treated with sulphuretted hydrogen, mercury is indicated by the presence of a black precipitate, which does not dissolve in warm nitric acid.

The further treatment of the black sulphide may be undertaken in two ways:--

(1) It is collected on a porcelain dish, with the addition of a little nitric acid, and evaporated to dryness in order to destroy organic matter. Hydrochloric and a few drops of nitric acid are next added; the action is aided by a gentle heat, the solution finally evaporated to dryness on the water-bath, and the residue taken up by warm distilled water. The solution is that of a persalt of mercury, and the mercury can be separated by electrolysis, or indicated by the tests already detailed.

(2) The other method, and the most satisfactory, is to mix the sulphide while moist with dry carbonate of soda, make it into a pellet which will easily enter a reducing or subliming tube, dry it carefully, and obtain a sublimate of metallic mercury.

A neat method of recognising mercury when deposited as a film on copper has been proposed by E. Brugnatelli:[944] the copper, after being washed, is transferred to a glass vessel, and a porcelain lid, on which a drop of gold chloride solution has been placed, adjusted over the dish. The whole is heated by a water-bath. The mercury vapour reduces the gold chloride, and gold is deposited as a bluish-violet stain; 1/10 mgrm. mercury may by this test be identified.

[944] _Gazzetta_, xix. 418-422.

Of special methods for the separation and detection of mercury, Ludwig’s[945] is, without a doubt, the best when organic matters have to be dealt with; the finely divided solid substances are boiled for some hours with hydrochloric acid, strength 20 per cent.; then the liquid is cooled to 60°, and potassic chlorate added in half gramme quantities until the dark liquid becomes clear; the liquid is cooled and filtered, and the substances on the filter washed with water. To the filtrate 5 grms. of zinc dust are added, and the liquid is violently shaken from time to time; a second portion is afterwards added, and also vigorously shaken. After some hours the clear liquid is separated from the zinc and the zinc washed, first with water, then with a little soda solution, and finally, again with water. The zinc is now collected on a glass-wool filter, treated with absolute alcohol to remove water, and dried by suction in a stream of air. The zinc is put into a combustion-tube, the tube being drawn out into a thin capillary extremity, and a combustion made, the mercury collecting at the capillary part. It is a necessary refinement, should the zinc be contaminated with a trace of organic matter, to pack the combustion-tube as follows:--First, the zinc dust on which any mercury present has been deposited, then a plug of asbestos; next, some cupric oxide; and lastly, some pure zinc dust. Bondzynski[946] prefers to use copper rather than zinc; for he says that zinc so frequently contains cadmium, which latter metal also gives a mirror, so that, unless the mercury is afterwards identified by turning it into an iodide, error may be caused.

[945] _Zeit. f. physiolog. Chemie_, 1882, i. 495; _Chem. Centrblt._, 1892, ii. 941.

[946] _Zeit. f. anal. Chem._, xxxii. 302-305.

§ 854. =Estimation of Mercury.=--All pharmaceutical substances containing mercury, as well as the sulphide prepared in the wet way, and minerals, are best dealt with by obtaining and weighing the metal in the solid state. The assay is very simple and easy when carried out on the method that was first, perhaps, proposed by Domeyko. A glass tube (which should not be too thin), closed at one end, is bent, as shown in the figure, the diameter should be about three lines, the length from 7 to 8 inches, the shorter arm not exceeding 2 inches. The powdered substance is mixed with two or three times its weight of litharge, and introduced into the tube at _a_. The portion of the tube containing the mercury is at first heated gently, but finally brought to a temperature sufficient to fuse the substance and soften the glass. The mercury collects in an annular film at _b_ in the cooler limb, and may now, with a little management of the lamp, be concentrated in a well-defined ring; the portion of the tube containing this ring is cut off, weighed, then cleansed from mercury, and reweighed. Many of the pharmaceutical preparations do not require litharge, which is specially adapted for ores, and heating with sodic carbonate (in great excess) will suffice. Mercury mixed with organic matter must be first separated as described, by copper or gold, the silvered foil rolled up, dried, introduced into the bent tube, and simply heated without admixture with any substance; the weight may be obtained either by weighing the foil before and after the operation, or as above.

§ 855. =Volumetric Processes for the Estimation of Mercury.=--When a great number of mercurial preparations are to be examined, a volumetric process is extremely convenient. There are several of these processes, some adapted more particularly for mercuric, and others for mercurous compounds. For mercuric, the method of Personne[947] is the best. The conversion of the various forms of mercury into corrosive sublimate may be effected by evaporation with aqua regia, care being taken that the bath shall not be at a boiling temperature, or there will be a slight loss.

[947] _Comptes Rendus_, lvi. 68; Sutton’s _Vol. Anal._, 177.

Personne prefers to heat with caustic soda or potash, and then pass chlorine gas into the mixture; the excess of chlorine is expelled by boiling, mercuric chloride in presence of an alkaline chloride not being volatilised at 100°. The standard solutions required for this process are:--

(1) 33·2 grms. of potassic iodide in 1 litre of water, 1 c.c. = 0·01 grm. Hg, or 0·01355 grm. HgCl₂.

(2) A solution of mercuric chloride containing 13·55 grms. to the litre, 1 c.c. = 0·1 grm. Hg.