Chapter XLIII: Part IX: Inorganic Poisons (1)

I.--PRECIPITATED FROM A HYDROCHLORIC ACID SOLUTION BY HYDRIC SULPHIDE--PRECIPITATE YELLOW OR ORANGE.[700]

Arsenic--Antimony--Cadmium.

[700] Fresenius has pointed out that sulphur may mask small quantities of arsenic, antimony, tin, &c., and he recommends that the turbid liquid in which apparently nothing but sulphur has separated should be treated as follows:--A test-tube is half filled with the liquid, and then a couple of c.c. of petroleum ether or of benzene added, the tube closed by the thumb, and the contents well shaken. The sulphur dissolves, and is held in solution by the solvent, which latter forms a clear upper layer. If traces of a metallic sulphide were mixed with the sulphur, thin coloured films are seen at the junction of the two layers, and the sulphides may also coat the tube above the level of the liquid with a slight faintly-coloured pellicle (_Chem. News_, Jan. 4, 1895).

1. ARSENIC.

§ 707. =Metallic Arsenic=, at. wt. 75, specific gravity of solid 5·62 to 5·96, sublimes without fusion in small quantities at 110° (230° F.) _Guy_. It occurs in commerce in whitish-grey, somewhat brittle, crystalline masses, and is obtained by subjecting arsenical pyrites to sublimation in earthen retorts, the arsenic being deposited in suitable receivers on sheet iron. Metallic arsenic is probably not poisonous, but may be changed by the animal fluids into soluble compounds, and then exert toxic effects--volatilised metallic arsenic is easily transformed in the presence of air into arsenious acid, and is therefore intensely poisonous.

§ 708. =Arsenious Anhydride--Arsenious Acid--White Arsenic--Arsenic=, As₂O₃ = 198; specific gravity of vapour, 13·85; specific gravity of opaque variety, 3·699; specific gravity of transparent variety, 3·7385. Composition in 100 parts, As 75·75, O 24·25; therefore one part of metallic arsenic equals 1·32 of As₂O₃. It is entirely volatilised at a temperature of 204·4°.

In analysis it is obtained in brilliant octahedral crystals as a sublimate on discs of glass, or within tubes, the result of heating a film of metallic arsenic with access of air. It is obtained in commerce on a very large scale from the roasting of arsenical pyrites. As thus derived, it is usually in the form of a white cake, the arsenious acid existing in two forms--an amorphous and a crystalline--the cake being generally opaque externally, whilst in the centre it is transparent. According to Kruger, this change from the crystalline to the amorphous condition is dependent upon the absorption of moisture, no alteration taking place in dry air. Both varieties of arsenious anhydride are acid to test-paper.

The solubility of arsenious acid is often a question involving chemical legal matters of great moment. Unfortunately, however, no precisely definite statement can be made on this point, the reason being that the two varieties of arsenic occur in very different proportions in different samples. Both the amorphous and crystalline varieties having very unequal solubilities, every experimenter in succession has given a different series of figures, the only agreement amid the general discrepancy being that arsenic is very sparingly soluble in water.

The statement of Taylor may, however, be accepted as very near the truth, viz., that an ounce of cold water dissolves from half a grain to a grain. According to M. L. A. Buchner,[701] one part of crystalline arsenious acid dissolves after twenty-four hours’ digestion in 355 parts of water at 15°; and the amorphous, under the same condition, in 108 of water. A boiling solution of the crystalline acid, left to stand for twenty-four hours, retains one part of acid in 46 of water; a similar solution of the amorphous retains one of arsenic in 30 parts of water, _i.e._, 100 parts of water dissolve from 2·01 to 3·3 parts of As₂O₃.

[701] _Bull. de la Société Chem. de Paris_, t. xx. 10, 1873.

Boiling water poured on the powdered substance retains in cooling a grain and a quarter to the ounce; in other words, 100 parts of water retain ·10. Lastly, arsenious acid boiled in water for an hour is dissolved in the proportion of 12 grains to the ounce, _i.e._, 100 parts of water retain 2·5.

K. Chodomisky[702] has investigated the solubility of recrystallised arsenious acid in dilute acids, and his results are as follows:--100 c.c. of 1·32 per cent. hydrochloric acid dissolves 1·15 grm. As₂O₃ at 18·5°. 100 c.c. of 6 per cent. hydrochloric acid dissolves 1·27 grm. at 18·5°. 100 c.c. of pure hydrochloric acid of the ordinary commercial strength dissolves 1·45 grm. As₂O₃. 100 c.c. of dilute sulphuric acid at 18° dissolves about 0·54 grm.; at 18·5° from 0·65 to 0·72 grm.; and at 80° from 1·09 to 1·19 grm.

[702] _Chem. Centrbl._, 1889, 569.

§ 709. =Arsine--Arseniuretted Hydrogen=, H₃As.--Mol. weight, 78; vol. weight, 39; specific gravity, 2·702; weight of a litre, 3·4944 grammes; percentage composition, 95·69 As, 4·31 H; volumetric composition, 2 vol. H₃As = half vol. As + 3 vol. H. A colourless inflammable gas, of a fœtid alliaceous odour, coercible into a limpid colourless liquid at a temperature of from -30° to -40°. The products of the combustion of arseniuretted hydrogen are water and arsenious acid; thus, 2H₃As + 6O = 3H₂O + As₂O₃. If supplied with air in insufficient quantity, if the flame itself be cooled by (for example) a cold porcelain plate, or if the gas pass through a tube any portion of which is heated to redness, the gas is decomposed and the metal separated. Such a decomposition may be compared to the deposit of carbon from ordinary flames, when made to play upon a cooled surface. It may also be decomposed by the electric spark,[703] _e.g._, if the gas is passed slowly through a narrow tube 0·7 to 0·8 mm. internal diameter, provided with wires 0·5 to 0·6 mm. apart, and a small induction coil used connected with two large Bunsen’s cells, then, under these conditions, arsenic as a metal is deposited in the neighbourhood of the sparks. For the decomposition to be complete, the gas should not be delivered at a greater speed than from 10 to 15 c.c. per minute. The gas burns with a blue-white flame, which is very characteristic, and was first observed by Wackenroder. It cannot, however, be properly seen by using the ordinary apparatus of Marsh, for the flame is always coloured from the glass; but if the gas is made to stream through a platinum jet, and then ignited, the characters mentioned are very noteworthy.

[703] N. Klobrikow, _Zeit. Anal. Chem._, xxix. 129-133.

Oxygen or air, and arsine, make an explosive mixture. Chlorine decomposes the gas with great energy, combining with the hydrogen, and setting free arsenic as a brown cloud; any excess of chlorine combines with the arsenic as a chloride. Sulphur, submitted to arseniuretted hydrogen, forms sulphuretted hydrogen, whilst first arsenic and then sulphide of arsenic separate. Phosphorus acts in a similar way. Arseniuretted and sulphuretted hydrogen may be evolved at ordinary temperatures without decomposition; at the boiling-point of mercury (350°) they are decomposed, sulphide of arsenic and hydrogen being formed; thus, 3H₂S + 2AsH₃ = As₂S₃ + 6H₂, a reaction which is of some importance from a practical point of view. Many metals have also the property of decomposing the gas at high temperatures, and setting hydrogen free. Metallic oxides, again, in like manner combine with arsenic, and set water free, _e.g._, 3CuO + 2H₃As = Cu₃As₂ + 3H₂O.

Arsine acts on solutions of the noble metals like phosphuretted hydrogen, precipitating the metal and setting free arsenious acid; for example, nitrate of silver is decomposed thus--

12AgNO₃ + 2H₃As + 3H₂O = As₂O₃ + 12HNO₃ + 12Ag.

Vitali[704] thinks the reaction is in two stages, thus:--

[704] _L’Orosi_, 1892, 397-411.

(1) 2AsH₃ + 12AgNO₃ = 2(Ag₃As3AgNO₃) + 6HNO₃.

(2) 2(Ag₃As,3AgNO₃) + 6H₂O = 6HNO₃ + 6Ag₂ + 2H₃AsO₃.

This reaction admits of valuable practical application to the estimation of arsenic; for the precipitated silver is perfectly arsenic-free; the excess of nitrate of silver is easily got rid of by a chloride of sodium solution, and the absorption and decomposition of the gas are complete.

In cases of poisoning by arsine, the blood, when examined by the spectroscope (a process the analyst should never omit where it is possible), is of a peculiar inky colour, and the bands between D and C are melted together, and have almost vanished. Such blood, exposed to oxygen remains unaltered.

§ 710. =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. In the course of numerous experiments on dogs, Stadelmann[705] found that by making them breathe a dose of arsine, which would not be immediately fatal, icterus was always produced under these circumstances, and could be always detected by the appearance of the tissues. The bile is remarkably thickened, and the theory is, that in such cases the jaundice is purely mechanical, the gall-duct being occluded by the inspissated bile. Rabbits experimented upon similarly showed increased biliary secretion, but no jaundice; while it was proved that cats are not so sensitive to arsine as either rabbits or dogs. There are not wanting instances of arsine having been breathed by man--the discoverer of the gas, Gehlen, was in fact the first victim on record. In order to discover a flaw in his apparatus he smelt strongly at the joints, and died in eight days from the effects of the inhalation.

[705] _Die Arsenwasserstoff-Vergiftung, Archiv f. exper. Path. u. Pharm._, Leipzig, 1882.

Nine persons, workmen in a factory, were poisoned by arsine being evolved during the treatment by hydrochloric acid of silver-lead containing arsenic. Three of the nine died; their symptoms were briefly as follows:--

(1) H. K., 22 years old; his duty was to pour hydrochloric acid on the metal. Towards mid-day, after this operation, he complained of nausea, giddiness, and _malaise_. In the afternoon he felt an uncommon weight of the limbs, and an oppression in breathing. His fellow-workmen thought that he looked yellow. On going home he lay down and passed into a narcotic sleep. Next morning he went to his work as usual, but was not capable of doing anything; he passed bloody urine several times throughout the day, and fell into a deep sleep, from which he could scarcely be roused. On the third day after the accident, a physician called in found him in a deep sleep, with well-developed jaundice, the temperature moderately high, pulse 100. On the fifth day the jaundice diminished, but it was several months before he could resume his work.

(2) J. T., aged 19, suffered from similar symptoms after five and a half hours’ exposure to the gas. He went home, vomited, was jaundiced, and suffered from bloody urine; in six days became convalescent, but could not go to work for many months.

(3) C. E. was very little exposed, but was unwell for a few days.

(4) L. M., 37 years old, was exposed two days to the gas; he vomited, had bloody urine, passed into a narcotic sleep, and died in three days from the date of the first exposure.

(5) J. S., aged 40, was exposed for two days to the gas; the symptoms were similar to No. 4, there was suppression of urine, the catheter drawing blood only, and death in eight days.

(6) M. E., 36 years old; death in three days with similar symptoms.

(7), (8), and (9) suffered like Nos. 1 and 2, and recovered after several months.

The chief _post-mortem_ appearance was a dirty green colour of the mucous membrane of the intestines, and congestion of the kidneys. Arsenic was detected in all parts of the body.[706]

[706] Trost, _Vergiftung durch Arsenwasserstoff bei der technischen Gewinnung des Silbers, Vierteljahrsschrift f. gericht. Med._, xviii. Bd., 2 Heft, S. 6, 1873.

Two cases are detailed by Dr. Valette in Tardieu’s _Étude_.[707] A mistake occurred in a laboratory, by which a solution of arsenic (instead of sulphuric acid) was poured on zinc to develop hydrogen. Of the two sufferers, the one recovered after an illness of about a week or ten days, the other died at the end of twenty-eight days. The main symptoms were yellowness of skin, vomiting, bloody urine, great depression, slight diarrhœa, headache, and in the fatal case a morbiliform eruption. In a case recorded in the _British Medical Journal_, November 4, 1876, there were none of the usual symptoms of gastric irritation, but loss of memory of recent acts, drowsiness, and giddiness.

[707] Ambroise Tardieu, _Étude Médico-légale sur l’Empoisonnement_, Obs. xxv. p. 449.

§ 712. =The Sulphides of Arsenic.=--Of the sulphides of arsenic, two only, realgar and orpiment, are of any practical importance. _Realgar_, As₂S₂ = 214; specific gravity, 3·356; composition in 100 parts, As 70·01, S 29·91; average composition of commercial product, As 75, S 25. Realgar is found native in ruby-red crystals, and is also prepared artificially by heating together 9 parts of arsenic and 4 of sulphur, or 198 parts of arsenious anhydride with 112 parts of sulphur, 2As₂O₃ + 7S = 2As₂S₂ + 3SO₂. It is insoluble in water and in hydrochloric acid, but is readily dissolved by potassic disulphide, by nitric acid, and by aqua regia. It is decomposed by caustic potash, leaving undissolved a brown sediment (As₁₂S), which contains 96·5 per cent. of arsenic. The dissolved portion is readily converted into arsine by aluminium.

§ 713. =Orpiment, or Arsenic Trisulphide.=--As₂S₃ = 246; specific gravity, 3·48; composition in 100 parts, As 60·98, S 39·02; found native in crystals, presents itself in the laboratory usually as a brilliant yellow amorphous powder, on passing sulphuretted hydrogen through an acid solution of arsenious acid or an arsenite. It is very insoluble in water (about one in a million, _Fresenius_), scarcely soluble in boiling concentrated hydrochloric acid, and insoluble generally in dilute acids. Red fuming nitric acid dissolves it, converting it into arsenic and sulphuric acids; ammonia and other alkaline sulphides, the alkalies themselves, alkaline carbonates, bisulphide of potassium, and aqua regia, all dissolve it readily. In the arts it is used as King’s yellow (see p. 532). Tanners also formerly employed a mixture of 90 parts of orpiment and 10 of quicklime, under the name of _Rusma_, as a depilatory; but the alkaline sulphides from gas-works are replacing this to a great extent.

§ 714. =Haloid Arsenical Compounds.--The Chloride of Arsenic=, AsCl₃ = 181·5; specific gravity liquid, 0° 2·205; boiling-point 134° (273·2°F.), is a heavy, colourless, oily liquid, which has been used as an escharotic in cancerous affections (principally by quacks). In one process of detecting and estimating arsenic, the properties of this substance are utilised (see p. 575). It is immediately decomposed by water into arsenious and hydrochloric acids.

=The Iodide of Arsenic= (AsI₃) is used occasionally in skin diseases, but is of little interest to the analyst; it is commonly seen in the form of brick-red brilliant flakes.

§ 715. =Arsenic in the Arts.=--The metal is used in various alloys; for example, speculum metal is made of tin, copper, and a little arsenic; white copper is an alloy of copper and arsenic; shot is composed of 1000 parts of lead mixed with 3 of arsenic; the common Britannia metal used for tea-pots, spoons, &c., often contains arsenic; and brass is bronzed with a thin film of arsenic. It was formerly much employed in the manufacture of glass, but is being gradually superseded. It is also now used to some extent in the reduction of indigo blue, and in that of nitro-benzole in the manufacture of aniline.

In cases of suspected poisoning, therefore, and the finding of arsenic in the stomach, or elsewhere, it may be set up as a defence that the arsenic was derived from shot used in the cleansing of bottles, from the bottles themselves, or from metal vessels, such as tea-pots, &c.

The arsenic in all these alloys being extremely insoluble, any solution to a poisonous extent is in the highest degree improbable. It may, however, be necessary to treat the vessels with the fluid or fluids which have been supposed to exert this prejudicial action, and test them for arsenic. The treatment should, of course, be of a severe and exhaustive character, and the fluids should be allowed to stand cold in the vessels for twenty-four hours; then the effect of a gentle heat should be studied, and, lastly, that of boiling temperatures. The analysis of the alloy itself, or of the glass, it would seldom be of value to undertake, for the crushed and finely divided substance is in a condition very different from that of the article when entire, and inferences drawn from such analytical data would be fallacious.

Arsenious anhydride is also used for the preservation of wood, and is thrown occasionally into the holds of vessels in large quantities to prevent vegetable decomposition. In India, again, a solution of arsenic is applied to the walls as a wash, in order to prevent the attacks of insects.

§ 716. =Pharmaceutical, Non-officinal, and other Preparations of Arsenic.=--(1) =Pharmaceutical Preparations.=--The Liquor arsenicalis (Fowler’s solution), or solution of arsenic of the pharmacopœia, is composed of:--

Carbonate of Potash, 87 grains (5·64 grms.)
Arsenious Acid, 87 „ (5·64 „ )
Compound Tincture of Lavender, 5 drachms (17·72 c.c.)

dissolved in 1 pint (567·9 c.c.) of water; every ounce, therefore, contains 4·3 grains of arsenious acid (or 100 c.c. = ·9As₂O₃); the strength is therefore nearly 1 per cent.

=Liquor Ammonii Arsenitis= (not officinal) is made of the same strength, ammonium carbonate being substituted for potassic carbonate.

The _hydrochloric solution of arsenic_ is simply arsenious acid dissolved in hydrochloric acid; its strength should be exactly the same as that of Fowler’s solution.

A solution of _arseniate of soda_[708] contains the _anhydrous_ salt in the proportion of 4 grains to the ounce (·9 in 100 c.c.) of water.

[708] 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. Officinal in U.S., France, and Norway.

=Pilula Asiatica= (not officinal) is composed of arsenious acid, extract of gentian, and black pepper. There is 1/12th of a grain (5·4 milligrams) of arsenious acid in each pill.

=Dr. De Valanguis’ Solutio solventes mineralis= is composed of 30 grains of As₂O₃ dissolved by 90 minims of HCl in 20 oz. of water; strength = 0·034 per cent. As₂O₃.

(2) =Veterinary Arsenical Medicine.=--Common veterinary preparations containing arsenic are:--A ball for worms, containing in parts--

Calomel, 1·3 per cent.
Arsenious Acid, 1·3 „
Tin Filings, 77·9 „
Venice Turpentine,[709] 19·5 „

[709] The Venice turpentine is rarely found in ordinary commerce, what is sold under that name consisting of black resin and oil of turpentine.

A common tonic ball:[710]--

[710] A similar preparation in common use has the addition of sulphate of zinc.

Arsenious Acid, 5 to 10 grains (·324 to ·648 grm.)
Aniseed, ½ oz. (14·1744 grms.)
Opium, 30 grains ( 1·94 „ )
Treacle, q. s.

An arsenical ball, often given by grooms to horses for the purpose of improving their coats, contains in 100 parts:--

Arsenious Acid, 2·5 per cent.
Pimento, 19·2 „
Extract of Gentian, 78·3 „

Another ball in use is composed of arsenic and verdigris (acetate of copper), of each 8 grains (·518 grm.); cupric sulphate, 20 grains (1·3 grm.); q. s. of linseed meal and treacle.

(3) =Rat and Fly Poisons, &c.=--An arsenical paste sold for rats has the following composition:--

Arsenious Acid, 5·0 per cent.
Lampblack, ·6 „
Wheat Flour, 46·3 „
Suet, 46·3 „
Oil of Aniseed, a small quantity.

Another rat poison is composed as follows:--

White Arsenic, 46·8 per cent.
Carbonate of Baryta, 46·8 „
Rose-pink,[711] 5·8 „
Oil of Aniseed, ·2 „
Oil of Rhodium, ·2 „

[711] Alum and carbonate of lead coloured with Brazil and peach woods.

Various arsenical preparations are used to kill flies; the active principle of the brown “_papier moure_” is arsenious acid. A dark grey powder, which used to be sold under the name of fly-powder, consisted of metallic arsenic that had been exposed some time to the air.

=Fly-water= is a strong solution of arsenious acid of uncertain strength, sweetened with sugar, treacle, or honey. Another fly-poison consists of a mixture of arsenious acid, tersulphide of arsenic, treacle, and honey.

(4) =Quack and other Nostrums.=--The analyst may meet with several quack preparations for external use in cancer. A celebrated arsenical paste for this purpose is composed of:--

Arsenious Acid, 8 per cent.
Cinnabar, 70 „
Dragon’s Blood, 22 „

=Frères Come’s Cancer Paste= is composed of arsenious acid, 1; charcoal, 1; red mercury sulphide, 4; water, q. s.

The tasteless “_ague drops_” used in the fen countries are simply a solution of arsenite of potash.

=Davidson’s Cancer Remedy= consists, according to Dr. Paris, of equal parts of arsenious acid and powdered hemlock.

In India, arsenic given as a medicine by native practitioners, or administered as a poison, may be found coloured and impure, from having been mixed either with cow’s urine, or with the juice of leaves, &c.[712]

[712] Chevers, _Med. Jurisprudence for India_, p. 116.

Arsenious acid is used by dentists to destroy the nervous pulp of decayed and painful teeth, about the twenty-fifth of a grain (2·5 mgrms.) being placed in the cavity. A common formula is arsenious acid, 2; sulphate of morphine, 1; creasote, q. s. to make a stiff paste. There is no record of any accident having resulted from this practice hitherto; but since the dentist seldom weighs the arsenic, it is not altogether free from danger.

(5) =Pigments, &c.=--_King’s yellow_ should be As₂S₃, the trisulphide of arsenic or orpiment. It is frequently adulterated with 80 to 90 per cent. of arsenious acid, and in such a case is, of course, more poisonous. King’s yellow, if pure, yields to water nothing which gives any arsenical reaction.

A blue pigment, termed _mineral blue_, consists of about equal parts of arsenite of copper and potash, and should contain 38·7 per cent. of metallic arsenic (= to 51·084 As₂O₃H) and 15·6 of copper.

=Schweinfurt green= (Syn. _Emerald-green_), (CuAs₂O₄)₃Cu(C₂H₃O₂)₂ is a cupric arsenite and acetate, and should contain 25 per cent. of copper and 58·4 per cent. of arsenious acid. In analysis, the copper in this compound is readily separated from the arsenic by first oxidising with nitric acid, and then adding to the nitric acid solution ammonia, until the blue colour remains undissolved. At this point ammonium oxalate is added in excess, the solution is first acidified by hydrochloric or nitric acid, and, on standing, the copper separates completely (or almost so) as Oxalate, the arsenic remaining in solution.

Another method is to pass SH₂ to saturation, collect the sulphides on a filter, and, after washing and drying the mixed sulphides, oxidise with fuming nitric acid, evaporate to dryness, and again treat with nitric acid. The residue is fused with soda and potassic nitrate, the fused mass is dissolved in water, acidulated with nitric acid, and the copper is precipitated by potash; the solution is filtered, and in the filtrate the arsenic is precipitated as ammonio-magnesian arseniate or as trisulphide.[713]

[713] P. Gucci, _Chem. Centrbl._, 1887, 1528.

=Scheele’s green= (CuHAsO₃) is a hydrocupric arsenite, and contains 52·8 per cent. of arsenious anhydride and 33·8 per cent. of copper.

(6) =External Application of Arsenic for Sheep, &c.=--Many of these are simply solutions of arsenic, the solution being made by the farmer. Most of the yellow sheep-dipping compounds of commerce are made up either of impure carbonate of potash, or of soda ash, arsenic, soft soap, and sulphur. The French _bain de Tessier_ is composed of:--

Arsenious Acid, 1·00 kgrm.
Ferrous Sulphate, 10·00 „
Peroxide of Iron, 0·40 „
Gentian Powder, 0·20 „

This is to be added to 100 kgrms. of water. Another common application consists of alum and arsenic (10 or 12 to 1), dissolved in two or three hundred parts of water.

(7) =Arsenical Soaps, &c.=--Arsenic is used in preserving the skins of animals. One of the compounds for this purpose, known under the name of _Bécoeur’s arsenical soap_, has the following composition:--

Camphor, 3·4 per cent.
Arsenic, 20·2 „
Carbonate of Potash, 56·2 „
Lime,[714] 20·2 „

[714] The dust from the preserved skins of animals has caused, at least, one case of poisoning. _Ann. d’Hyg. Pub. et de Méd. Lég._, 2 sér., 1870, t. xxxiii, p. 314.

(8) =Arsenical compounds= used in pyrotechny:--

Parts.
Blue fires--(1) Realgar, 2
Charcoal, 3
Potassic Chlorate, 5
Sulphur, 13
Nitrate of Baryta, 77
-----
(2) Sulphur, 40·9
Nitre, 36·8
Sulphide of Antimony, 12·3
„ Arsenic, 5
Charcoal, 5
-----
Green fires--Metallic Arsenic, 2
Charcoal, 3
Chlorate of Potash, 5
Sulphur, 13
Nitrate of Baryta, 7
------
Light green fire--Charcoal, 1·75
Sulphide of Arsenic, 1·75
Sulphur, 10·50
Chlorate of Potash, 23·25
Nitrate of Baryta, 62·50
------
White fire--(1) Arsenious Acid, ·76
Charcoal, 1·63
Sulphide of Antimony, 12·27
Nitrate of Potash, 36·59
Sulphur, 48·75
------
(2) Realgar, 6·1
Sulphur, 21·2
Nitrate of Potash, 72·7
------

§ 717. =Statistics.=--During the ten years 1883-92 there were registered in England and Wales 113 deaths from arsenic; of these 57, or about half, were suicidal deaths, and 5 were classed under the head of “murder”; the rest were due to accident. The age and sex distribution of persons dying from accidental or suicidal arsenical poisoning are detailed in the following table:--

DEATHS FROM ARSENIC DURING THE TEN YEARS 1883-1892.

ACCIDENT OR NEGLIGENCE.

Ages, 1-5 5-15 15-25 25-65 65 and Total
above
Males, 1 4 3 23 6 37
Females, 4 ... 3 4 3 14
---------------------------------------
Total, 5 4 6 27 9 51
---------------------------------------

SUICIDE.

Ages, 15-25 25-65 65 and Total
above
Males, 3 32 2 37
Females, 5 12 3 20
----------------------------
Total, 8 44 5 57
----------------------------

§ 718. =Law Relative to the Sale of Arsenic.=--By the 14th of Vict. c. 12, every person selling arsenic is bound to keep a written record of every particular relative to each transaction, such as the name, abode, and calling of the purchaser, the purpose for which the poison is required, and the quantity sold, &c. These particulars are to be signed also by the purchaser. No person (sec. 2) is allowed to sell arsenic to any one unknown to the seller, unless in the presence of a witness whom the seller is acquainted with. The arsenic sold (sec. 3) is to be mixed with soot or indigo in the proportion of half an ounce of indigo to a pound of arsenic. It, therefore, follows that the coloured substance should not contain more than 70 per cent. of arsenious acid. The Act applies to all the colourless preparations of arsenic: but it is not to affect chemists in making up prescriptions for medical men, or in supplying medical men; nor is it to affect the wholesale dealers in supplying arsenic to retail shops, &c. The penalty for conviction is £20, or less.[715]

[715] Commercial arsenic is often much adulterated, especially with gypsum, chalk, &c. These are most readily detected by subliming the arsenic. The sublimed arsenic itself may not be entirely pure, sometimes containing arsenical sulphides and antimonious oxide.

§ 719. =Dose.=--The smallest dose of arsenic known to have proved fatal to a human being is ·16 grm. (2½ grains). Farriers and grooms are in the habit of giving as much as l·3 grm. (20 grains) a day to a horse, so that the poisonous dose for this animal must be very large.

The maximum dose for the horned cattle appears to be from ·32 to ·38 grm. (5 to 6 grains); that for a dog is 16 mgrms. (¼ grain), and even this may, in the smaller kinds, cause illness.

The following may be considered as _dangerous doses_ of arsenic:--·13 grm. (2 grains) for an adult; 1·9 grm. (30 grains) for a horse; ·64 grm. (10 grains) for a cow; and 32 to 64 mgrms. (½ to 1 grain) for a dog.

§ 720. =Effects of Arsenious Acid on Plants.=--If the root or stem of a plant is immersed in a solution of arsenious acid, the hue of the leaves soon alters in appearance, the green colour becomes of a whitish or brownish hue, and the plant withers; the effect being very similar to that produced by hot water. The toxic action may be traced from below upwards, and analysis will detect minute quantities of arsenic in all portions of the plant.

It has, however, been shown by Gorup-Besanez,[716] that if arsenious acid be mixed with earth, and plants grown in such earth, they only take up infinitesimal quantities of arsenic. Hence, in cases of cattle poisoning, any defence based upon the alleged presence of arsenic in the pasture will be more ingenious than just.

[716] _Annal. d. Chemie u. Pharmacie_, Bd. cxxvii., H. 2, 243.

The influence of arsenical fumes as evolved from manufactories upon shrubs and trees is in general insignificant. Pines and firs, five to six years old, have been known to suffer from a disease in which there is a shedding of the leaves, the more tender herbage being at the same time affected. Whatever dangers the practice of steeping corn intended for seed in a solution of arsenious acid, as a preventive of “smut,” may possess, it does not appear to influence deleteriously the growth of the future plant.

Superphosphate of manure is frequently rich in arsenic. Dr. Edmund Davy asserts that plants to which such manure is applied take up arsenic in their tissues, and M. Andonard has made a similar statement. Tuson[717] has also undertaken some experiments, which confirm Andonard and Davy’s researches. The bearing of this with relation to the detection of arsenic in the stomachs of the herbivora needs no comment.

[717] Cooley’s _Dictionary_, Art. “Arsenic.”

§ 721. =Effects on Animal Life--Animalcules.=--All infusoria and forms of animalcule-life hitherto observed perish rapidly if a minute quantity of arsenious acid is dissolved in the water in which they exist.

=Insects.=--The common arsenical fly-papers afford numerous opportunities for observing the action of arsenic on ordinary flies; within a few minutes (five to ten after taking the poison into their digestive organs) they fall, apparently from paralysis of the wings, and die. Spiders and all insects into which the poison has been introduced exhibit a similar sudden death. It is said that in the neighbourhood of arsenical manufactories there is much destruction among bees and other forms of insect life.

=Annelids.=--If arsenious acid is applied to the external surface of worms or leeches, the part which it touches perishes first, and life is extinguished successively in the others. If a wound is made first, and the arsenious acid then applied to it, the effects are only intensified and hastened. There is always noticed an augmentation of the excretions; the vermicular movements are at first made more lively, they then become languid, and death is very gradual.

=Birds.=--The symptoms with birds are somewhat different, and vary according to the form in which the poison is administered, viz., whether as a vapour or in solution. In several experiments made by Eulenberg on pigeons, the birds were secured under glass shades, and exposed to the vapour of metallic arsenic vaporised by heat. It is scarcely necessary to remark that in operating in this way, the poisoning was not by metallic arsenic vapour, but by that of arsenious acid. One of these experiments may be cited:--A pigeon was made to breathe an atmosphere charged with vapour from the volatilisation of metallic arsenic. The bird was immediately restless; in thirty minutes it vomited repeatedly, and the nasal apertures were noticed to be moist; after a little while, the bird, still breathing the arsenious acid atmosphere, was much distressed, shook its head repeatedly, and yawned; in fifty minutes the respiration was laboured, and in fifty-nine minutes there was much vomiting. On removing the bird, after it had been exposed an hour to the vapour (·16 grm. of metallic arsenic having been evaporated in all), it rapidly recovered.

Six days after, the pigeon was again exposed in the same way to the vapour, but this time ·56 grm. of metallic arsenic was volatilised. In fifteen minutes there was retching, followed by vomiting. On taking it out after an hour it remained very quiet, ate nothing, and often puffed itself out; the breathing was normal, movements free, but it had unusual thirst. On the second and third day the excretions were frequent and fluid; the cardiac pulsations were slowed, and the bird was disinclined to move. On the fourth day it continued in one place, puffing itself out; towards evening the respirations slowed, the beak gaping at every inspiration. On attempting flight, the wings fluttered and the bird fell on its head. After this it lay on its side, with slow, laboured respiration, the heart-beats scarcely to be felt, and death took place without convulsions, and very quietly. On examining the organs after death, the brain and spinal cord were very bloodless; there were ecchymoses in the lungs; but little else characteristic. The experiment quoted has a direct bearing upon the breathing of arsenical dust; as, for example, that which floats in the air of a room papered with an easily detached arsenical pigment. Other experiments on birds generally have shown that the symptoms produced by arsenious acid in solution, or in the solid form, in a dose insufficient to destroy life, are languor, loss of appetite, and the voidance of large quantities of liquid excreta like verdigris. With fatal doses, the bird remains quiet; there are fluid, sometimes bloody, excretions; spasmodic movements of the pharynx, anti-peristaltic contraction of the œsophagus, vomiting, general trembling of the body, thirst, erection of the feathers, and laboured respiration. The bird becomes very feeble, and the scene mostly closes with insensibility and convulsions.

=Mammals=, such as cats, dogs, &c., suffer from symptoms fairly identical with those observed in man; but the nervous symptoms (according to P. Hugo) do not predominate, while with rabbits and guinea-pigs, nervous symptoms are more marked and constant.[718] There are vomiting, purging, and often convulsions and paralysis before death. It has been noticed that the muscles after death are in a great state of contraction. The slow poisoning of a dog, according to Lolliot,[719] produced an erythematous eruption in the vicinity of the joints, ears, and other parts of the body; there were conjunctivitis, increased lachrymal secretion, and photophobia; the hair fell off.

[718] _Archiv f. exper. Path. u. Pharmakol_, Leipzig, 1882.

[719] _Étude Physiol. d’Arsène_, Thèse, Paris, 1868.

§ 722. =Effects of Arsenious Acid on Man.=--The symptoms produced by arsenious acid vary according to the form of the poison--whether solid, vaporous, or soluble--according to the condition of bodily health of the person taking it, and according to the manner in which it is introduced into the animal economy, while they are also in no small degree modified by individual peculiarities of organisation and by habit, as, for instance, in the arsenic-eaters.

=Arsenic-Eaters.=--In all European countries grooms and horse-dealers are acquainted with the fact that a little arsenic given daily in the corn improves the coat, increases, probably, the assimilation of the food, and renders the horse plump and fat. On the Continent grooms have been known to put a piece of arsenic, the size of a pea, in a little oatmeal, make it into a ball, tie it up in a linen rag, and attach it to the bit; the saliva dissolves, little by little, the poison, while both the gentle irritation and physiological action excite a certain amount of salivation, and the white foam at the mouth, and the champing of the horse, are thought vastly to improve the appearance. Shot, which contains a small quantity of arsenic, have been used for the same purpose, and from half a pound to a pound of small shot has been given to horses. When a horse has been for a long time dosed with arsenic, it seems necessary to continue the practice; if this is not done, the animal rapidly loses his condition. The explanation probably is, that the arsenic stimulates the various cells and glands of the intestinal tract to a superaction, the natural termination of which is an enfeeblement of their secreting power--this especially in the absence of the stimulus. Turning from equine involuntary arsenic-eaters, we find the strange custom of arsenic-eating voluntarily pursued by the races of lower Austria and Styria, especially by those dwelling on the mountains separating Styria from Hungary. In India also (and especially in the Punjaub) the same practice prevails, and here it is often taken as an aphrodisiac. The mountaineers imagine that it increases the respiratory power, nor is there wanting some evidence to show that this is actually the fact, and medicinal doses of arsenic have been in use for some time in cases of asthma and other diseases of the chest. The arsenic-eaters begin with a very small dose, which is continued for several weeks or months, until the system gets accustomed to it. The amount is then slightly augmented until relatively large doses are taken with impunity. In one case[720] it appears that a countryman, in good health, and sixty years of age, took daily 4 grains of arsenious acid, a habit which he had inherited from his father, and which he in turn bequeathed to his son.

[720] Tardieu, _op. cit._

The existence of such a custom as arsenic-eating, in its literal sense, has more than once been doubted, but all who have travelled over Styria and other places where the habit prevails have convinced themselves that the facts have not been overstated. For example, Dr. Maclagan, in company with Dr. J. T. Rutter,[721] visited Styria in 1865, and having carefully weighed 5 or 6 grains of arsenic, saw these doses actually swallowed by two men. On collecting their urine, about two hours afterwards, abundant quantitative evidence of its presence was found; but in neither of the men were there the slightest symptoms of poisoning. It is obvious that the existence of such a habit might seriously complicate any inquiry into arsenical poisoning in these regions.

[721] _Edin. Med. Journ._, April 1865; _Brit. and For. Med. Chir. Journ._, Oct. 1865.

§ 723. =Manner of Introduction of Arsenic.=--Arsenious acid exerts a poisonous action, whether it is taken by the stomach, or introduced into the system by any other channel whatever. The differences in the symptoms produced by external application (as through a wound), and by swallowing arsenious acid in substance or in solution, are not so marked as might be expected. It was probably Hunter who first distinctly recognised the fact that arsenic, even when introduced outwardly by application to an abraded surface, exerts a specific effect on the mucous membrane of the stomach. Brodie[722] states, “Mr. Home informed me that in an experiment made by Mr. Hunter himself, in which arsenic was applied to a wound in a dog, the animal died in twenty-four hours, and the stomach was found to be considerably inflamed. I repeated this experiment several times, taking the precaution of always applying a bandage to prevent the animal licking the wound. The result was that the inflammation of the stomach was commonly more violent and more immediate than when the poison was administered internally, and that it preceded in appearance the inflammation of the wound.”

[722] _Phil. Trans._, 1812.

§ 724. =Cases of Poisoning by the External Application of Arsenic.=--A mass-poisoning by the external use of arsenical violet powder to infants occurred in England some years ago. Two deaths from this cause were established by coroners’ inquests.[723] Dr. Tidy found the violet powders used in the two cases to have the following composition:--

[723] “Gleanings in Toxicology,” by C. Meymott Tidy, M.B.--_Lancet_, Aug. 21, 1878.

1. 2.
Per cent. Per cent.
Arsenious Acid, 38·5 38·3
Starch (Potato), 54·8 55·4
Magnesia, &c. 6·7 6·3[724]

[724] Two recipes were handed in at the coroner’s inquest which pretty fairly represent the composition of ordinary commercial violet powder:--

_First Quality, sold at 7s. per gross._

Starch Powder, 28 lbs.
Magnesia, 1½ lb.
Orris-root, 1 lb.
Violet Perfume, 1 oz.
Essence of Roses, 5 drops.

_Second Quality, sold at 6s. per gross._

Terra Alba (Sulphate of Lime), 14 lbs.
Potato Starch, 21 lbs.
Magnesia, 3 lbs.
Orris-root, 1½ lb.
Violet Perfume, 1½ oz.
Essence of Roses, 5 drops.

Although the children were poisoned by absorption through the skin (unless it is allowed that some may have found its way in the form of arsenical dust into the throat, or, what is still more probable, that the infants may from time to time have seized the puff-ball and _sucked_ it), the large quantity of ·421 grm. (6·5 grains) of arsenious acid was separated in the one case, and ·194 grm. (3 grains) in the other. In these cases arose the question which is sure to recur in legal inquiries into poisoning by absorption, viz., whether the poison lying on the surface and folds of the skin could not have been mixed during the _post-mortem_ examination with the organs of the body? In these particular cases special care appears to have been taken, and the answer was satisfactory. It is not amiss, however, to call attention to the extreme precaution which such instances necessitate.

A woman, aged 51, had used a solution of arsenious acid to cure the itch; erysipelas of the body, however, followed, and she died after a long illness--one of the symptoms noted being trembling and paresis of the limbs.[725] In a case recorded by Desgranges,[726] a young chambermaid had applied to the unwounded scalp an arsenical ointment for the purpose of destroying vermin. She also suffered from a severe erysipelas, and the hair fell off. Quacks have frequently applied various arsenical pastes to ulcers and cancerous breasts with a fatal result. Instances of this abound; in one, a charlatan applied to a chronic ulcer of the leg an arsenical caustic; the patient showed symptoms of violent poisoning, and died on the sixth day.[727] In another, a lady suffering from some form of tumour of the breast, applied to an unqualified practitioner, who made from fifteen to twenty punctures with a lancet in the swelling, covered a piece of bread with an arsenical compound, and applied the bread thus prepared to the breast. Twelve hours afterwards symptoms of violent gastric irritation commenced; and vomiting and a sanguinolent diarrhœa followed, with death on the fifth day. Arsenic was found in all the organs.[728] Such examples might be multiplied. Arsenic has been in more than one case introduced criminally into the vagina with a fatal result.[729] Foderé, _e.g._, has recorded the case of a maid-servant who poisoned her mistress by intentionally administering several arsenical enemata.[730] Arsenious acid again has been respired in the form of vapour. One of the best instances of this is recorded by Taylor, and was the subject of a trial at the York Lent Assizes, 1864. The prisoner placed some burning pyrites at the doorway of a small room, in which there were eight children, including an infant in the cradle. The other children were removed speedily, but the infant was exposed to the vapour for an hour; it suffered from vomiting and diarrhœa, and died in twenty-four hours. There was slight inflammation of the stomach and intestines, the brain and lungs were congested, and the lining membrane of the trachea of a bright red colour. Arsenic was detected in the stomach, in the lungs, and spleen. The pyrites contained arsenic, and the fatal fumes were in effect composed of sulphurous and arsenious acids.

[725] Belloc, _Méd. Lég._, t. iv. p. 124.

[726] _Recueil de la Soc. de Méd. de Paris_, t. vi. p. 22, An. vii.; also Tardieu, _Étude Méd. Légale, sur l’Empoisonnement_, Obs. xxvii. p. 457.

[727] Mean, _Bibliothèque Méd._, t. lxxiv., 1821, p. 401.

[728] Tardieu, _op. cit._, Obs. xxix.; Dr. Vernois, _Ann. d’Hyg. et de Méd. Lég._, t. xxxvi., 1st ser., p. 141, 1846.

[729] Ansiaulx, _Clinique Chirurgicale_. Mangor (_Acta. Societ. Reg. Hafniens_, iii. p. 178) gives the case of a man who poisoned his three wives successively with arsenic--the two last by introducing into the vagina a powder composed of flour and arsenic. Another similar case is related by Brisken. Mangor made experiments on mares, showing that when arsenic is applied to the vagina, death may result from inflammation.

[730] _Méd. Légale_, iv.

§ 725. =Arsenic in Wall-Papers.=--It is now an accepted fact that arsenical colours on wall-papers cause illness. The symptoms are those of chronic poisoning, and present nothing distinctive from the effects produced from small doses of arsenic.

Kirschgasser[731] has described the symptoms in detail of twenty-six cases. That arsenic is actually present in patients suffering is often susceptible of proof, by examining skilfully and carefully a considerable volume (from one to two days’ collection) of the urine; in most of the cases thus examined arsenic has been discovered. This poisoning is produced, sometimes from the dust, at others from a volatile compound of arsenic, which has the following properties:--It is very volatile (perhaps a gas), it has a strong alliaceous odour, it is not entirely decomposed by a solution of silver nitrate, but is apparently decomposed by a boiling acid solution of potassic permanganate. The author suggests that it may be a compound of CO and As, but this is only a supposition. The existence of this volatile substance has been settled beyond all question by the experiments of Gosio,[732] confirmed by those of Charles Robert Sanger.[733]

[731] _Vierteljahr. f. gericht Med._, N. F., ix. 96.

[732] _Azione di alcune Muffe sui Compositi fissi d’Arsenico. Ministero dell’ Interno, Laboratori Scientifici della Direzione di Sanita_, Roma, 1892.

[733] “On the Formation of Volatile Compounds of Arsenic from Arsenical Wall-Papers,” _American Academy of Arts and Sciences_, vol. xxix.

This substance appears to be readily enough produced by the action of the common moulds upon organic matter in the presence of small amounts of arsenic; the moulds vary in this property: _Mucor_, _Mucedo_, and _Aspergillum glaucum_ react well; on the contrary, _Penicillium glaucum_, _Mucor ramosus_, and several others have either no action, or the action is but slight. One mould, the _Penicillium brevicaule_, has quite a special endowment in forming this peculiar arsenical compound; so much so, that Gosio has proposed its use as a reagent for arsenic, the garlic odour being perceived when the fungus is made to grow in solutions containing organic matter and only traces of arsenic.

§ 726. =Forms of Arsenical Poisoning.=--There are at least four distinct forms of arsenical poisoning, viz., an acute, subacute, a nervous, and a chronic form.

=Acute Form.=--All those cases in which the inflammatory symptoms are severe from the commencement, and in which the sufferer dies within twenty-four hours, may be called acute. The commencement of the symptoms in these cases is always within the hour; they have been known, indeed, to occur within eight minutes, but the most usual time is from twenty minutes to half an hour. There is an acrid feeling in the throat, with nausea; vomiting soon sets in, the ejected matters being at first composed of the substances eaten; later they may be bilious or even bloody, or composed of a whitish liquid. Diarrhœa follows and accompanies the vomiting, the motions are sometimes like those met with in ordinary diarrhœa and English cholera, and sometimes bloody. There is coldness of the extremities, with great feebleness, and the pulse is small and difficult to feel. The face, at first very pale, takes a bluish tint, the temperature falls still lower; the patient sinks in collapse, and death takes place in from five to twenty hours after the taking of the poison.

There can scarcely be said to be any clinical feature which distinguishes the above description from that of cholera; and supposing that cholera were epidemic, and no suspicious circumstance apparently present, there can be little doubt that a most experienced physician might mistake the cause of the malady, unless surrounding circumstances give some hint or clue to it. In the acute form diarrhœa may be absent, and the patient die, as it were, from “shock.” This was probably the cause of death in a case related by Casper,[734] that of Julius Bolle, poisoned by his wife. He took an unknown quantity of arsenic in solution at seven in the morning, and in about three-quarters of an hour afterwards suffered from pain and vomiting, and died in little more than three hours. There were no signs of inflammation in the stomach and intestines, but from the contents of the stomach were separated ·0132 grm. of arsenious acid, and ·00513 grm. from pieces of the liver, spleen, kidneys, lung, and blood. The dose actually taken is supposed not to have been less than ·388 grm. (6 grains).

[734] Case 188 in Casper’s _Handbuch_.

§ 727. =The Subacute Form.=--The subacute form is that which is most common; it exhibits some variety of phenomena, and individual cases vary much in the matter of time. The commencement of symptoms is, as in the most acute form, usually within the hour, but exceptions to this rule occur. In a case quoted by Taylor,[735] and recorded by M. Tonnelier, the poison did not cause any marked illness for eight hours; it was found, on _post-mortem_ examination, that a cyst had been formed in the stomach which sheathed the arsenic over, and in some degree explained this delay. In another case, again, ten hours elapsed, and this is considered to be the maximum period yet observed. As with the acute form, there is a feeling of nausea, followed by vomiting, which continues although the stomach is quite empty; at first the ejected matter is a watery fluid, but later it may be streaked with blood. The tongue is thickly coated; there is great thirst, but the drinking of any liquid (even of ice-cold water) increases the vomiting. Nearly always pain is felt in the epigastrium, spreading all over the abdomen, and extending to the loin (which is tense and tender on pressure). Deglutition is often painful, and is accompanied by a sort of spasmodic constriction of the pharyngeal muscles. Diarrhœa follows the vomiting, and has the same characters as that previously described; occasionally, however, this feature is absent. In the case recorded by Martineau,[736] a man, aged 25, was seized at 10 A.M. suddenly with vomiting, which persisted all that day and the next, during which time the bowels were obstinately confined. On the second day a purgative was administered, whereupon diarrhœa set in, and continued until his death, which occurred in about two days and sixteen hours from the commencement of the symptoms. This case is also remarkable from the absence of pain or tenderness of the abdomen.

[735] Taylor’s _Principles and Practice of Jurisprudence_, vol. i. p. 251; Flandin, vol. i. p. 535.

[736] Tardieu, _op. cit._, Obs. xix.

In subacute cases the urine has several times been suppressed, and it is generally scanty and red in colour. Irregularity of the heart’s action and feebleness are tolerably constant phenomena. As the end approaches, there is excessive muscular weakness, the face is pale, the eyes hollow; the mucous membranes first, and then the skin, take a bluish tint; the skin itself is covered with perspiration, and there has been noticed a peculiar odour, which has been likened to arsine (arseniuretted hydrogen). The respiration is troubled, convulsive movements of the limbs have been observed, and cramps in the calves of the legs; death follows in a variable time--from twenty-four hours to several days. In certain cases there is a curious remission after violent symptoms, the patient rallies and seems to have recovered; but the appearance is deceptive, for the symptoms recur, and death follows. Recovery may also take place partially from the primary effects, and then inflammatory changes in the stomach, &c., set in, with fever and the ordinary symptoms which are common in all internal inflammation.