Arsenic

“ Solution.—Where, as in crude arsenic, the substance is arsenious oxide (As2O3) mixed with impurities, the arsenic is best got into solution by warming with caustic soda, and neutralising the excess with hydrochloric acid; it will be present as sodium arsenite. Metals and alloys are acted on by means of nitric acid; or the arsenic may be at the same time dissolved and separated by distilling with a strongly-acid solution of ferric chloride, in the way described under Volumetric Methods. ”

“ Arsenic may be detected by dissolving the substance in hydrochloric acid, or in aqua regia (avoiding an excess of nitric acid) , and adding a little of this solution to the contents of a small flask in which hydrogen is being made by the action of zinc and hydrochloric acid. The ignited jet of hydrogen assumes a blue colour if arsenic is present, and a cold porcelain dish held in the flame (fig. 67) becomes coated with a dark deposit of metallic arsenic. Antimony produces a similar effect, but is distinguished by the insolubility of its deposit in a cold solution of bleaching-powder. ”

“ A saturated solution of arsenic in water is preferable I think to the above operose preparation of it; as no error can happen in weighing the ingredients, and it more certainly therefore possesses an uniform strength. Put much more white arsenic reduced to powder into a given quantity of distilled water, than can be dissolved in it. ”

“ Our oxide of arsenic is a factitious substance, prepared by sublimation from cobalt: it is much more deleterious than auripigmentum or orpiment. Servitor and Avicenna have described the factitious arsenic, or oxide of arsenic of the moderns. The Arabian chemist Geber treats largely and ingeniously of orpiment, which he holds to be closely allied to sulphur. ”

“ Another oxide likewise exists, which contains two equivalents of metal and five of oxygen, and, possessing strong acid properties, is denominated arsenic acid. The sesquioxide and arsenic acid unite with bases, and produce compounds which, with the exception of those they form with the alkalis, are mostly insoluble. Metallic arsenic unites with sulphur in two proportions, forming an orange-red and a sulphur-yellow compound. The compounds of arsenic have very little chemical action with vegetable and animal principles. ”

“ This saline compound, which I call Liver of Arsenic, takes up a much greater quantity of Arsenic than is necessary for the perfect saturation of the alkali. It has the appearance of a glue, which is so much the thicker the more Arsenic it contains. Its smell is disagreeable; it attracts the moisture of the air, and does not crystallize; it is easily decompounded by any acid whatever, which precipitates the Arsenic and unites with the alkali. ”

“ It is found nearly pure, and in considerable abundance, in different parts of Germany; usually occurring in masses of various shapes, and in combination with a small portion of iron, gold, or silver.
The arsenic sold in the shops, and too well known for its poisonous qualities, is an oxide (21) of this metal artificially prepared.
In some mines on the Continent arsenic is very abundant, and is found extremely injurious to the workmen. Being very volatile, its fumes affect and destroy the lungs, and occasion death in a short time to many of them. ”

“ Arsine in the Arts, &c.—In the bronzing of brass, in the desilverising of lead by zinc, and subsequent treatment of the silver zinc with hydrochloric acid, in the tinning of sheet iron, and similar processes, either from the use of acids containing arsenic as an impurity, or from the application of arsenic itself, arsine is evolved.
§ 711. Effects on Animals and Man of Breathing Arsine.—The most general effect on mammals is to produce jaundice, bloody urine, and bile. ”

“ Arsenic has the power, to a certain extent, of arresting putrefactive changes; the stomach may, therefore, be found well preserved, and with the signs of inflammatory action present after the lapse of many months, and after putrefaction has far advanced in other parts of the body. When a person is suspected of having been poisoned with arsenic, and nothing but the skeleton is left for investigation, the arsenic should be looked for specially in the bones of the pelvis and the neighbouring vertebræ (Watt‘s Dictionary of Chemistry, Sup.) ”

“ Arsenic has of course been long known as a tonic more or less applicable to phthisis, as to other states of debility. But the points so sharply brought out by the French author—the limitation of the therapeutic action of arsenic to the non-febrile periods and cases, and (on the other hand) its extraordinary efficacy within these limits, in restoring flesh and strength and general health, and wonderfully amending the state of the lungs themselves—are so important that they demand the serious and immediate attention of English physicians. ”

“ The hydrogen comes off regularly even in the cold, but it is best to apply a little heat. This test will evolve arsine from arsenious acid, and also from arsenic trisulphide; but it is not available for the detection of arsenic, when the arsenic is in the form of arsenic acid. ”

“ That such a practice may lead to the taking of arsenic as a confirmed habit there is also evidence to prove, and the writer has met with more than one instance, in which the habit of taking solution of arsenic in large quantities has been contracted by women. ”

“ II. Effect of Arsenic on the Growth of Higher Plants. 1. Toxic effect. (a) Toxic action of arsenic compounds in water cultures in the presence of nutrients.
The poisonous action of arsenic on plants has long been recognised. Chatin (1845) gave accounts of tissues poisoned by strong arsenical [53] solutions. Nobbe, Baessler and Will (1884) carried on water culture experiments with buckwheat, oats, maize and alder, and found that arsenic was a particularly strong poison for these plants. ”

“ Binz has advanced a new and original theory as to the action of arsenious acid; he considers that the protoplasm of the cells of many tissues possess the power of oxidising arsenious acid to arsenic acid, and this arsenic acid is again, by the same agency, reduced to arsenious acid, in this way, by the alternate oxidation and reduction of the arsenious acid, the cells are decomposed, and a fatty degeneration takes place. Thus arsenic causes fatty changes in the liver, kidney, and other cells by a process analogous to the action of phosphorus. ”

“ Arsenic is a specific irritant poison. Almost all the compounds of this metal are poisonous. The term "arsenic" is, however, most commonly applied, not to the metal itself, but to its lower oxide, arsenious oxide, which is also known as white arsenic. By whatever channel arsenic is introduced into the system, it invariably affects specifically the stomach and intestines, causing congestion or inflammation. ”

“ Painted on the skin while wet is bad enough; but what shall we say to those — well, we will not use harsh terms — who calmly tell you that they always use dry arsenic. Incredible as the statement may appear to the scientist, yet it is true that I have seen a man plunge his hand in the most matter-of-fact way into a box containing dry arsenic, and coolly proceed to dust it on a skin. ”

“ We are told by Newman, that the utmost caution is necessary to avoid the fumes of arsenic, and that it is on account of the danger arising from them that this mineral has been so little examined by the chymists; but according to Dr. Percival’s late observations, they seem to have been mistaken. I have, says he, some doubt, whether the vapours of arsenic be so poisonous as is commonly supposed, and if the candid reader will excuse the digression, I will lay before him my reasons for it. ”

“ What do you esteem to be a complete test of arsenic being held in solution in any complicated body?—I don’t conceive that there is any complete test, but the evaporating of the solution, and reproducing the arsenic in its metallic state. ”

“ Jackson speaks of recovery after the ingestion of two ounces of arsenic by the early employment of an emetic. Walsh reports a case in which 600 gr. of arsenic were taken without injury. The remarkable tolerance of arsenic eaters is well known. Taylor asserts that the smallest lethal dose of arsenic has been two gr., but Tardieu mentions an instance in which ten cgm. (1 1/2 gr.) has caused death. Mackenzie speaks of a man who swallowed a large quantity of arsenic in lumps, and received no treatment for sixteen hours, but recovered. It is added that from two masses passed by the anus 105 gr. ”

“ It is a fine grayish-black powder, formed by exposing powdered arsenic for a long time to the air; but it also frequently contains fragments of the metal. It is usually considered by chemists to be a mixture of metallic arsenic and its white oxide.
It is acted on by water, the white oxide being found ere long in solution by its proper tests. Oxidation and solution, however, are also effected upon pure metallic arsenic in the same manner. A thousand grains of water take up a grain in the course of half an hour when boiled on the metal. ”

“ Size is largely used for fixing colour; thus, the proper conditions for the development of arseniurretted hydrogen—the most dangerous compound of arsenic—are present. As much as 17 grains of arsenic have been discovered in each square foot of a wall-paper. Now, arsenic is sometimes given internally for certain skin and other diseases, but the dose is only from 1 ∕ 60 to 1 ∕ 12 grain; the capacity for poisoning of such a paper as the above will therefore be evident. ”

“ But with all this miscalculation the approximate amount of arsenic can only be swelled up to four-tenths of a grain, less than one-fourth of a fatal dose, and it was demonstrated that every other part of the body, urine, bile, stomach, contents of stomach, heart, lungs, spleen, fluid from mouth, and even bones, were all found to be free from arsenic. ”

“ The formula for arseniate of soda is Na2HAsO47H2O, but it sometimes contains more water.
Liquor Arsenii et Hydrargyri Iodidi (Donovan’s Solution of Arsenic) .—This is not officinal, but is used to some extent in skin diseases; it is a solution of the iodides of mercury and arsenic; strength about 1 per cent. of each of the iodides.
Arseniate of Iron, Fe3As2O8, is an amorphous green powder, used to some extent in medicine. It should contain 33·6 per cent. of metallic arsenic.
Clemen’s Solution.—A solution of the bromide and arseniate of potassium; strength equal to 1 per cent. arsenious acid. ”

“ Arsenic in its pure form, unless taken in large doses, rarely kills outright. Indeed the human system has shown itself capable of absorbing small doses of arsenic regularly without any apparent evil effect. There is a province in Austria known for its "arsenic eaters." They are hardy mountaineers who after years of regular use of the drug, even in quantities far beyond a medicinal dose, seem to enjoy excellent health. The attempt to kill a human being with one dose of arsenic in its pure form results in symptoms at once distressing and characteristic. ”

“ Arsenic.—The arseniates and metallic arsenic itself impart to the blowpipe flame a fine blue color, provided that there is no other body present which may have a tendency to color the flame with its characteristic hue. The sublimate of arsenious acid which surrounds the assay, will give the same blue flame, when dissipated by the oxidation flame. The platinum forceps will answer for the exhibition of the color of arsenic, even though the salts be arseniates, whose bases possess the property of imparting their peculiar color to the flame, such as the arseniate of lime. ”

“ I had occasion, some years ago, to examine such a specimen of king’s yellow, with which a woman had killed her child. A proper insoluble sulphuret of arsenic, like the native or the Saxon, may be prepared by transmitting sulphuretted hydrogen gas through any arsenical solution. It consists of 38·09 sulphur, and 60·92 of metallic arsenic, and is not remarkably poisonous. The finest [914] kinds of native orpiment are reserved for artists; the inferior are used for the indigo vat. They are all soluble in alkaline lyes, and in water of ammonia. ”

“ The sulphuric acid aided by heat destroys organic matter sufficiently to prevent frothing in the apparatus and dissolves out arsenic from a state of combination with organic principles; and nitric acid afterwards converts any arsenic in the half-charred mass into the soluble arsenic acid. It has been employed with success in various medico-legal proceedings in France. It answers well for detecting oxide of arsenic in the viscera, muscles, and other parts of the body into which the poison has been conveyed through absorption. ”

“ A few persons are very susceptible to the effects of dry arsenic, others are not. If the blood is in a healthy condition there is little to fear from it, except through gross carelessness. I have used, all told, probably more than a hundred and fifty pounds of arsenic in various forms, and never had an hour's illness in consequence, nor anything more serious than a sore finger.
Corrosive sublimate is much more powerful and more dangerous. It should never be used in the preparation of a skin before it is mounted; after mounting it may, with care, be used quite safely. ”

“ Arsenic.—Arsenic is probably the most popular of the rat poisons, owing to its cheapness, yet our experiments prove that, measured by the results obtained, arsenic is dearer than strychnin. Besides, arsenic is extremely variable in its effect upon rats, and if the animals survive a first dose it is very difficult to induce them to take another. ”