100

CORROSIVE SUBLIMATE IN ORGANIC LIQUIDS.

pass in for some time. Hydrosulphuret of ammonia gives a similar precipitate in the solution;-thus clearly distinguishing corrosive sublimate from arsenic. The test acts equally in an acid solution of the salt. The precipitated black sulphuret of mercury, dried and heated with carbonate of soda or metallic silver, easily furnishes a ring of pure metallic mercury. 4. Precipitation by metals.If we acidulate the liquid with a few drops of diluted muriatic acid, and introduce a slip of bright copper, or what is better, fine copper-gauze, it is soon coated with metallic mercury, having more or less of a silvery lustre, especially on friction. On heating the copper in a reduction-tube, the mercury may be obtained in well defined globules. 5. The galvanic test.-There are various ways in which galvanism may be applied to the detection of mercury in corrosive sublimate. Dr. Wollaston, on one occasion, employed an iron key and a guinea: he placed a drop of the suspected solution on a surface of gold, and touched it and the gold with the key-the mercury was deposited on the gold in a bright silvery stain. The following is a ready method of producing the metal:-Place a few drops of the solution on a clean surface of copper and slightly acidulate it with muriatic acid; then touch the copper through the solution with a slip of zinc-foil. Wherever the copper is touched by the zinc the mercury is deposited, and on washing the surface with diluted muriatic acid or ammonia a silvery stain is left, which is immediately dissipated by the heat of a spirit-lamp. The experiment may be modified by twisting a slip of zinc round a slip of bright copper, or copper-gauze, and introducing them into the liquid any change of colour or tarnish is very apparent on the copper. Mercury is deposited on both metals. A surface of gold with zinc is, perhaps, more delicate than a surface of copper as a test of the presence of mercury. Applied in a way to be presently explained, it will detect the metal when nearly every other method fails. Other tests have been proposed; but I omit all notice of them, because the foregoing are, in my opinion, quite sufficient for every practical purpose. [Value of these tests, according to Devergie:-Potash 7000; Proto-chloride of tin, 80,000; Sulph-hyd. 60,000; galvanic test, 80,000.]

In liquids containing organic matter.-The same process of analysis will apply to the vomited matters and contents of the stomach. Masses of corrosive sublimate may be sometimes locked up in thick viscid mucus; and in such cases, the coarse powder, being heavy, may be sometimes separated by simply agitating the viscid liquid in water, and then decanting it suddenly. This poison is decomposed and precipitated by many organic principles, such as albumen, fibrin, mucous membrane, also by gluten, tannic acid, and other vegetable substances. Thus, then, we cannot always expect to find it in a state of solution. We must filter in order to separate the liquid from the solid portion; and our first object will be to determine whether any of the poison is held in solution. For this purpose a portion of it may be shaken with one-third of its volume of ether, and after a time the ethereal liquid decanted and allowed to evaporate spontaneously in a watch-glass, or other convenient glass vessel. If corrosive sublimate be present in large quantity, white prismatic crystals will appear, which are rendered scarlet when touched with a solution of iodide of potassium. The other properties of the poison may also be brought out by dissolving the crystalline residue in water, filtering the solution through a wet filter, and applying the appropriate tests. The quantity of corrosive sublimate may be too small for this method of separation; then we may acidulate the liquid with about one-tenth part of its volume of muriatic acid, and introduce a slip of copper-gauze, at the same time warming the liquid. If the poison be present, even in minute quantity, the gauze speedily acquires a silvery gray colour, from a deposit of mercury. It should be well washed in water, in alcohol or ether, again in water, and then dried. On heating it in a reduction tube, a ring of fine metallic globules will appear in a detached form, and having a silvery white lustre. There is no angularity, transparency, or crystalline character about this sublimate, as in the case of arsenic-a fact speedily made evident under the microscope.

In order to remove any doubt, the ring of glass on which the sublimate is deposited may be broken up and warmed in a wide tube with a few drops of nitro-muriatic acid. On evaporating to dryness at a very low temperature (corrosive sublimate being volatile,) a residue having a prismatic crystalline character remains. These are crystals of corrosive sublimate re-formed from the globules of metallic mercury. When touched with a solution of iodide of potassium, they acquire a scarlet colour. In very fine sublimates this, or some corroborative experiments on their nature, are indispensably necessary.

The galvanic gold test may be thus applied:-Cut a slip of fine gold-foil, of about one inch in length and one-eighth of an inch in width; it should be just large enough to enter into a small reduction-tube. We then twist round this, in a spiral form, a slip of finely laminated zinc; acidulate the suspected liquid with a few drops of diluted muriatic acid, and suspend the gold and zinc by a thread in the midst of it. Several such pieces may be at once suspended in the liquid. According to the quantity of mercury present, the gold will be coated with a gray-coloured deposit, either immediately or in the course of a few hours. If at the end of ten or twelve hours the gold retain its bright yellow colour, there is probably no mercury present in a dissolved form, or the quantity is exceedingly minute. Supposing the gold to have lost its colour, owing to its having become completely coated, we should remove it and dip it in ether, and afterwards in distilled water, to wash off any corrosive sublimate and organic matter adhering to it: it should then be dried in air without being allowed to touch any surface, and introduced into a reduction-tube. The zinc may be in part dissolved; but as mercury is also deposited on this metal, whereby it is commonly rendered quite brittle, it may be introduced with the gold into the tube. On applying heat, a fine sublimate will soon appear in the cool part of the tube, which, if not perceptible to the eye, may be easily seen, by the aid of a common lens, to consist of minute globules of mercury. Fine wires of gold and zinc may be substituted for the foil.

Let us suppose that the filtered liquid contains no trace of a mercurial salt; we must now direct our attention to the analysis of the insoluble matters separated by filtration. These may be boiled in distilled water; the liquor filtered and tried by agitating it with one-third of its volume of ether. It will be found, when the analysis has not been long delayed, that most of the compounds which corrosive sublimate forms with organic matter, yield commonly sufficient poison for detection by boiling them in water. Should water fail in extracting the poison, the substance may be brought to dryness and heated with nitromuriatic acid until all the organic matter is decomposed, and the surplus acid expelled. The residue may then be digested in water and tested for mercury by the aid of copper-gauze or of gold and zinc. I have separated mercury from the liver by simply boiling it with muriatic acid, as in Reinsch's process for arsenic, and plunging into the liquid slips of copper-gauze.

A person may die from the effects of corrosive sublimate, and no mercury may be found in the tissues. A case of this kind occurred to me some years since at Guy's Hospital; and another, in which the deceased died in fifteen days from a large dose of corrosive sublimate in whiskey, has been reported by Dr. Geoghegan. On this occasion, although the local effects of the poison on the throat, stomach, and bowels were of an intense kind, the viscera, on careful analysis, yielded no trace of mercury: it had been entirely eliminated. (See Med. Gaz. vol. xlvi. p. 253.)

CALOMEL

This substance, now called chloride of mercury, although commonly regarded as a mild medicine, is capable of destroying life, even in comparatively small doses. Several cases have been already referred to, where excessive salivation, gangrene of the salivary organs, and death, have followed from the medicinal

102

WHITE PRECIPITATE. RED PRECIPITATE.

dose of a few grains. There is a case reported in the Med. Gaz. (xviii. 484,) in which a boy, aged fourteen, was killed in about three weeks by a dose of only six grains of calomel. It is singular that in this case neither the teeth nor the salivary glands were affected; still, considering the effects of calomel in other instances, it seems most probable that the ulceration and gangrene of the face which followed were due to it. Pereira mentions the case of a lady who was killed by a dose of twenty grains of calomel: she had previously taken a moderate dose without a sufficient effect being produced. Sobernheim states that a girl, aged eleven, took in twenty-four hours eight grains of calomel, for an attack of croup, and died in eight days from inflammation and ulceration of the mouth and fauces. In another instance, which occurred to Lesser, fifteen grains of calomel produced similar effects, with excessive salivation; and this patient also died in eight days. Meckel relates that twelve grains have destroyed life. (Lehrbuch der Ger. Med. 267.) Two cases of death from calomel, in children, are recorded in the Registration returns for 1840.

There are many other fatal cases on record, and the facts seem to leave no doubt that calomel may, in large doses, act as an irritant poison. It was supposed that these effects might be ascribed to this compound being adulterated with corrosive sublimate; but this supposition is not well founded. It has been further supposed that calomel might be converted into corrosive sublimate, by the free muriatic acid contained in the gastric secretions; but the very minute proportion in which this acid exists in the gastric juice, according to Dr. Prout, renders this explanation improbable.

WHITE PRECIPITATE. AMMONIO-CHLORIDE OF MERCURY.

This is an irritant compound, although little is known concerning its effects. In January, 1840, a young woman who had swallowed this substance was received into St. Thomas's Hospital. She had mixed it and taken it in water, but the quantity swallowed could not be ascertained. The stomach-pump was employed, mucilaginous drinks and olive oil were administered; and in the course of a few days she perfectly recovered. The symptoms under which she suffered were those of gastric-irritation. Judging from this case, white precipitate does not appear to be a very active preparation; yet still it must be regarded as a poison. One instance of death from salivation produced by this compound is recorded in the Registration returns for 1840, in a child, aged seven; and within the last two years there have been several attempts at murder by the administration of this substance. It is much used by the poor as a popular external remedy for the ringworm.

RED PRECIPITATE. RED OXIDE OF MERCURY.

This substance is poisonous, but instances of poisoning by it are very rare. The following case occurred at Guy's Hospital in 1833. A woman aged twentytwo, who had swallowed a quantity of red precipitate, was brought in, labouring under the following symptoms:-The surface was cold and clammy, there was stupor approaching to narcotism,-frothy discharge from the mouth, and occasional vomiting:-the vomited matters contained some red powder, which was proved to be red precipitate. There was considerable pain in the abdomen, increased by pressure; and there were cramps in the lower extremities. On the following day the fauces and mouth became painful, and the woman complained of a coppery taste. The treatment consisted in the use of the stomach-pump, and the free administration of albumen with gluten. She left the hospital four days afterwards, still under the influence of mercury. The quantity of oxide here taken was not ascertained. Sobernheim relates a case where a man, aged twenty-six, swallowed an ounce of red precipitate. He was speedily attacked with pain in the abdomen, nausea, purging, cramps, and general weakness. vomited matters consisted of masses of mucus containing red precipitate. He

The

CINNABAR.

BICYANIDE OF MERCURY.

TURBITH MINERAL.

103

continued to get worse, and died in less than forty-eight hours after taking the poison. On inspection the mucous membrane was found eroded and inflamed in patches, small particles of the poison being imbedded in it. The duodenum was in a similar state, and there was a large quantity of red precipitate in the contents of this viscus, as well as in the stomach. (Op. cit. 250.) [Alison relates a case in which a woman swallowed about thirty-five grains:-an emetic was immediately given, and the stomach-pump was used. A burning pain continued for some time after the evacuation of the stomach, but was relieved by bleeding, and the patient gradually recovered. (Lancet N. S. 19, 401.)—H.] A common opinion exists among the vulgar, that this compound is possessed of very active poisonous properties; hence it is sometimes administered with criminal design.

CINNABAR. VERMILION. PERSULPHURET OF MERCURY.

The term Cinnabar is applied to a dark and heavy compound of sulphur and mercury, while Vermilion is the same substance reduced to a fine powder. It is well known as a red pigment, and is often employed in colouring confectionary, wafers, &c. I have not been able to find any instance of its having acted as a poison on man. Orfila believes that it is not poisonous. It has, however, proved fatal to animals in the proportion of from thirty to seventy grains, even when applied externally to a wound. Cinnabar is sometimes used for giving a red colour to ointments, e. g. the sulphur ointment. In such cases the quantity is very small, and can do no injury even if swallowed.

The

Dr. Sutro has published a short abstract of a case in which the vapour of Vermilion applied externally produced severe symptoms. A woman, by the advice of a quack, applied this vapour to a cancerous breast. She employed three drachms of vermilion, covering herself with a sheet so that the vapour should only reach the body externally. After three fumigations, she suffered from severe salivation and violent fever, which continued for four weeks. right arm became cedematous. (Med. Times, Sept. 27, 1845, p. 17.) ["A patient in the surgical ward of the Louisville Hospital, labouring under a venereal ulcer of the palate, was directed to use mercurial fumigations, which he did in the manner and to the degree usually practised in the ward; but it proved fatal to him in less than half an hour." (Beck, ii. 596, from West. Jour. of Med. & Surg., 1840, 84.)-H.]

BICYANIDE OF MERCURY.

This is a substance which is but very little known, except to chemists, yet it is an active poison, and has caused death in one instance. In April, 1823, a person who had swallowed twenty grains of this compound (thirteen decigrammes) was immediately seized with all the symptoms of poisoning by corrosive sublimate, and died in nine days. There was continued vomiting, with excessive salivation, ulceration of the mouth and fauces, suppression of urine, purging, and lastly, convulsions of the extremities. On inspection, the mucous membrane of the stomach and intestinal canal was extensively inflamed. (Orfila, i. 583.) Dr. Christison quotes a case in which ten grains destroyed life within the same period of time. (On Poisons, p. 427.) As a poison, the bicyanide is probably not much inferior in activity to the bichloride of mercury.

TURBITH MINERAL. SUBSULPHATE OF PEROXIDE, OF MERCURY. Fatal cases of poisoning by this compound are by no means common. It is undoubtedly, although very insoluble, a strong irritant poison, and is capable of causing death in a comparatively small dose. A well marked instance of its fatal operation was communicated to the Pathological Society by Mr. Ward, in March, 1847. A boy, æt. 16, swallowed one drachm of this preparation on the night of February 19th. It produced a burning sensation in the mouth and throat, and

104

POISONING BY LEAD.

SUGAR OF LEAD.

vomiting in ten minutes. In about an hour there was paleness with anxiety of countenance, coldness of surface, constant sickness, sense of heat and constriction in the throat, and burning pain in the stomach with cramps. The irritability of the stomach continued in spite of treatment, and after two days there was salivation with mercurial fetor. The gums acquired a deep bluish tint and began to ulcerate. The patient died in about a week after he had taken the poison, without convulsions, and without suffering at any period from symptoms of cerebral disturbance. The principal post-mortem appearances were-inflammation of the oesophagus, its mucous membrane at the lower part peeling off; the inner surface of the stomach near the cardia and pylorus was covered with petechial spots; the small intestines were contracted, the inner coat reddened, and petechial spots were found, but chiefly in the large intestines. The parotid and submaxillary glands were swollen. Mercury was detected in the intestines. (See Med. Gaz. xxxix. 474.) From this account it will be perceived that turbith mineral has an action somewhat similar to corrosive sublimate, although it is certainly much less active.

NITRATES OF MERCURY.

These are corrosive poisons which are used for several purposes in the arts. They are solid white salts, easily dissolved by water, especially if there be a little excess of acid present. The acid pernitrate has already caused death in an interesting case reported by Mr. Bigsley in the Medical Gazette (vi. 329.) A butcher's boy dissolved some mercury in strong nitric acid, and swallowed about a teaspoonful of the solution. Soon afterwards he suffered the most excruciating pain in the pharynx, oesophagus, and stomach:-there was great anxiety, with cold skin, small pulse, colic, and purging. He became gradually weaker, and died in about two hours and a half. On inspection, the fauces, oesophagus, and stomach were found corroded and inflamed. Although he survived so short a time, the mucous membrane of the stomach was of a deep red colour. I have elsewhere related a singular case in which the application of the pernitrate of mercury to the throat as an escharotic caused immediate death by asphyxia. (See Guy's Hosp. Reports, Oct. 1850, 206.)

The acid nitrate of mercury has often been employed by accoucheurs as a local application in diseases of the neck of the uterus. In one instance in which it was thus used, the ordinary symptoms of mercurial poisoning showed themselves, and the patient appears to have suffered severely. (Med. Gaz. vol. xlv. p. 1025.)

CHAPTER XI.

ON POISONING BY LEAD-SUGAR OF LEAD-SYMPTOMS-CHRONIC POISONING BY SUGAR OF LEAD-POST-MORTEM APPEARANCES TREATMENT-QUANTITY REQUIRED TO DESTROY LIFE-CHEMICAL ANALYSIS-LEAD IN ORGANIC MIXTURES-CARBONATE OR WHITE LEAD -PAINTER'S COLIC-OXIDES-LITHARGE AND RED LEAD-ACCIDENTS FROM THE GLAZING OF POTTERY.

THIS is more frequently taken as a poison than any of the other salts, although cases of acute poisoning by lead in any form are very uncommon. In the Coroner's report for 1837-8 there is not a single instance. The substance is commonly met with in solid heavy crystalline masses, white, or of a brownishwhite colour: it much resembles loaf-sugar in appearance, and has often been