When introduced into the stomach of dogs, M. Barthez found that twenty drops on a full stomach had no particular effect; that thirty drops occasioned vomiting, and temporary acceleration of the pulse and breathing; and that from forty to sixty drops on an empty stomach brought on violent vomiting, sneezing, cough, dilated pupil and prostration, succeeded in a few hours by languor without any other symptom, and by death in four or five days. In the dead body he remarked numerous little ulcers of the villous coat, some of which had an ash-gray appearance at the bottom, while others were covered with a black slough, easily removed by friction. When the gullet was tied to prevent vomiting, less doses proved more quickly fatal. He likewise observed that the matter vomited in these experiments, even a few minutes after the administration of the poison, had no appearance or odour of bromine; whence it is reasonable to conclude, that, as in the instance of iodine, a chemical change takes place with the aid of certain vital operations, so that the bromine becomes hydrobromic acid.—The experiments of Dr. Butske assign to it more activity as a poison than those now related. For he found that a dog died in a day from taking only five grains dissolved in two ounces of water; and the symptoms were laborious breathing, loud cries, and convulsions. In the dead body he found the stomach internally chequered with bloody extravasation, and filled with bloody mucus, the duodenal mucous membrane universally injected, but the rest of the alimentary canal in a healthy state.—Dr. Glover remarked in such cases, besides the usual symptoms of an irritant action on the stomach, coryza, sneezing, salivation and difficult breathing. Sixty minims killed a cat in seventeen minutes, two fluid drachms a dog in five hours and a half, ten grains a rabbit in five minutes. A dog twice got twenty grains in solution and recovered, but died after a third dose of the same amount. Another got twenty grains in solution every two or three days for a month without injury. In some of these experiments hydrobromic acid was detected in the blood and urine.
Little is yet known of the effects of bromine on man. Butske found that a drop and a half in half an ounce of water produced a sense of heat in the mouth, gullet, and stomach, and subsequently colic pains; and that two drops and a half in an ounce of mucilage excited, in addition to the preceding symptoms, great nausea, hiccup, and increased secretion of mucus. On the other hand M. Fournet, who gave doses gradually increasing from two to sixty drops daily for many weeks, observed that the lowest doses excited itching in the hands and feet, and sometimes colic; that an increase in the quantity caused heat in the chest and nausea; and that forty-five drops occasioned also severe burning and sense of acidity in the stomach, which however were temporary. The appetite was in general rather improved, and the body became more plump.[[376]]—Bromine appears on the whole to be a pure local irritant. It acts most energetically when most thoroughly dissolved in water.
Hydrobromic acid seems from the experiments of Dr. Glover to be a pure irritant and corrosive, allied in action and energy to hydrochloric acid. The same experimentalist found that bromine of potassium in the dose of forty grains had sometimes little or no effect on dogs when injected into the blood-vessels, while in other instances less doses cause speedy death by paralysing the heart. Barthez observed that half a drachm in solution produced dulness and depression in dogs, but no other bad effect; and that two drachms retained in the stomach by tying the gullet occasioned death in three days with symptoms of irritant poisoning. M. Maillet observed that two ounces of this salt in the form of ointment, administered to a dog by rubbing it over his nose, and letting him lick it off and swallow it, had no effect whatever.[[377]]
CHAPTER V.
OF POISONING WITH ACETIC ACID.
Acetic acid, although in its ordinary state undoubtedly possessed of little activity as a poison, has nevertheless proved in some circumstances deleterious, and capable of occasioning death even in the human subject. It exists in various forms. The most common is ordinary vinegar, in which it is much diluted. Another common form is the pyroligneous vinegar, pyroligneous acid, or pyroligneous acetic acid, as it is variously called, which when impure has a reddish-brown colour, but when pure is almost or altogether colourless, and the strength of which is much greater than that of common vinegar. What is called proof vinegar has a density about 1005, and contains about four per cent. of concentrated acid. The pyroligneous acid sold in the shops of this town has a density about 1035, and contains about 25 per cent.; but the pyroligneous acid of the London Pharmacopœia is stronger, for its density is 1050, and 100 parts contain about 50 of the strong acid. A third form is the concentrated or pure acetic acid of the apothecary, which is familiarly known as the chief ingredient and menstruum of a common perfume, aromatic vinegar.
Section I.—Of the Tests for Acetic Acid.
In all its forms acetic acid is easily known by its very peculiar odour, together with its acid reaction on litmus. But if farther evidence of its nature be required, it will be requisite to neutralise the fluid suspected to contain it with carbonate of potass, and then to procure the acetate of potass by evaporation. This salt is known by its extreme tendency to deliquesce, and by a concentrated solution in water, yielding, when distilled with sulphuric acid, a fluid possessing the peculiar odour and pungency of concentrated acetic acid.
When in a state of compound admixture with organic substances, such as the contents of the stomach, it has been proved by late researches of Orfila,[[378]] that this acid may be present in considerable proportion without distinctly reddening litmus. For such mixtures the following process of analysis, devised by the Parisian professor, will be found convenient and effectual. The fluid being put into a retort with a receiver attached, the retort is to be heated in a muriate of lime bath till the residuum be dry. The distilled fluid may then be tested tentatively for sulphuric and muriatic acids; and these being proved to be absent, the acidity and peculiar smell of the liquid will supply strong presumption of the presence of acetic acid. This presumption may be turned to certainty by forming acetate of potass, as already directed for the pure diluted acetic acid.
Orfila has omitted in his paper a serious fallacy to which this, as well as every process for the detection of acetic acid in the contents of the stomach is exposed,—namely, that the natural secretions of the stomach, according to the researches of many physiologists, but more especially in recent times those of Tiedemann and Gmelin in Germany, and those of Leuret and Lassaigne in Paris, frequently contain a small proportion of acetic acid. Hence, the inference in favour of the introduction of acetic acid into the stomach from without, founded on the process related above, is only legitimate when the quantity discovered is considerable.—The medical jurist ought also to keep in mind that vinegar is a common remedy with the vulgar for many diseases, and especially for poisoning.