CHAPTER XXX.

OF POISONING WITH CARBAZOTIC ACID.

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

posed of carbon, azote, and oxygen.

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

In the dead body no particular alteration of structure was remarked. The heart examined immediately after death from the introduction of the poison into the stomach was found much gorged and motionless; but the irritability of the voluntary Annales de Chin. et de Phys. xxxv. 72. + Toxikologie, 373.

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

These facts form one of the most interesting additions made in recent times to the physiology of poisons. They supply unequivocal proof that some poisons are absorbed in the course of their operation, and may be found throughout the body after death. They likewise furnish strong presumptive evidence that, as formerly hinted, other poisons, which act on organs remote from the place where they are applied, and which have been sought for without success in the blood as well as in other fluids and solids throughout the body, have not been detected, merely because the physiologist does not possess such simple and extremely delicate means of searching for them.

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

CHAPTER XXXI.

OF THE POISONOUS GASES.

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

It has hitherto been only on the continent that use has been made of the deleterious gases for the purpose of self-destruction. Osiander mentions, that Lebrun, a famous player on the horn, suffocated himself at Paris in 1809 with the fumes of sulphur; and that an apothecary at Pyrmont killed himself by going into the Grotto del Cane there, which, like that near Naples, is filled with carbonic acid gas *. A late French journal relates the case of a young man who, urged by disappointment in love, tried to make away with himself by burning a charcoal choffer in his apartment +.

But these poisons come under the notice of the medical jurist chiefly because their effects may be mistaken for those of other kinds of violent death. Several mistakes of this nature are on record. Zacchias mentions the case of a man, who was found dead in prison under circumstances which led to the suspicion that he had been privately strangled by the governor. But Zacchias proved this to be impossible, and ascribed death to the fumes from a choffer of burning charcoal left in the room. A more striking instance of the kind occurred lately at London. A woman, who inhabited a room with other five people, alarmed the neighbours one morning with the intelligence that all her fellow-lodgers were dead. On entering the room they found two men and two women actually dead, and another man quite insensible and apparently dying. This man,

* Ueber den Selbstmord, p. 176.

Nouv. Bibl. Méd. 1827, iii. 91.

Quæstionum Medico-legalium, T. iii. 63. Consilium 44.

however, recovered; and as it was said that he was too intimate with the woman who gave the alarm, a report was spread that she had poisoned the rest, to get rid of the man's wife, one of the sufferers. She was accordingly put in prison, various articles in the house were carefully analyzed for poison, and an account of the supposed barbarous murder was hawked about the streets. At last the man who recovered remembered having put a choffer of coals between the two beds, which held the whole six people; and the chamber having no vent, they had thus been all suffocated *.-The following is a similar accident not less remarkable in its circumstances. Four people in Gerolzhofen in Bavaria, were found one morning in bed, some dead, others comatose. One only recovered. A neighbour who had supped with them, but slept at home, did not suffer. The stomach and intestines were found very red and black; and the coats of the stomach brittle. The contents of the stomach, the remains of their supper, and the wine were analyzed without any suspicious substance being found. A little smoke having been noticed in the room by those who first entered it, the stove and fuel were examined, but without furnishing any insight into the cause of the accident. At last the cellar was examined, and then it was found that one of the sufferers had heated a copper-vessel there so incautiously, that the fire communicated with the unplastered planks of the floor above. The planks had burnt with a low smothered flame, and the vapours passed through the crevices in the floor †.

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

M. Nysten, who has made the most connected train of experiments on this subject, conceived that a gas will not act through any other channel besides the lungs, if it exerts merely a negative action;-and that, on the contrary, it certainly possesses a direct and positive power, if it has nearly the same effects, in whatever way it is introduced into the body ‡. He

* London Courier, Jan. 16, 1823.

+ Buchner's Toxikologie, 331.

Nysten, Recherches Chimico-Physiologiques, p. 11.

therefore thought the best way to ascertain the action of the gases would be, to inject them into the blood,-conceiving that, after allowance is made for the mere mechanical effects of an aeriform body, the phenomena would point out the true operation of each.

His first object then was to learn what phenomena are caused by the mechanical action of atmospherical air. He found that four cubic inches and a half injected into the jugular vein of a dog, killed it immediately amidst tetanic convulsions, by distending the heart with frothy blood;-that a larger quantity introduced gradually caused more lingering death, with symptoms of oppressed breathing, which arose from gorging of the lungs with frothy blood;-and that a small quantity injected into the carotid artery towards the brain occasioned speedy death by apoplexy, which arose from the brain being deprived by means of the air of a due supply of its proper stimulus, the blood.

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

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

Two or three cubic inches of Sulphuretted Hydrogen caused tetanus and immediate death, when injected into the veins, although the gas was at once absorbed by the blood. The same

Nysten, Recherches Chimico-Physiologiques, passim.

+ Ibidem, p. 81.