Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 52

A perfectly clean and bright piece of copper, immersed in a slightly acid solution of mercury, becomes in a short time covered with a grey or whitish stain, which a.s.sumes a silvery l.u.s.tre when gently rubbed with a piece of soft cork or leather, and is removed by the subsequent application of heat. A single drop of liquid may be tested on a bright copper coin in this way.

The plate of copper with the deposit of mercury, obtained as above, after being washed with a weak solution of ammonia, and in distilled water, and dried by pressure between the folds of bibulous paper, may be cut into small pieces, and heated in a test-tube, in order to obtain metallic globules. When the suspected solution contains organic matter, bright copper filings may be employed, and the process modified so as nearly to resemble Reinsch's test for a.r.s.enious acid. According to Orfila, "sc.r.a.ped copper plate" is capable of detecting the presence of 1/80000th part of corrosive sublimate in a solution. MM. Trousseau and Reveil state that a plate of yellow copper (bra.s.s) is even more susceptible than one of red copper.

(Smithson's electrolytic test.) This consists in the use of a polished wire or plate of gold or copper round which a strip or thread of zinc or tin is wound in a spiral direction. The suspected liquid is acidulated with a few drops of hydrochloric acid, and after immersion for a longer or a shorter period (as half an hour to an hour or two), the gold will have become white if any mercury is present. The coil of zinc or tin is then removed from the gold, and the latter, after being washed and dried between the folds of bibulous paper, is heated in a test-tube, to obtain metallic globules, as before.

An ingenious extemporaneous application of the electrolytic test may be made as follows:--Place a drop or two of the suspected liquid on a clean and bright gold or copper coin, and apply a bright key, so that it may at once touch the edge of the coin and the solution. (See _engr._) An electric current will then be established as before, and a white spot of reduced mercury will appear on the surface of the metal, which may be recognised in the manner already explained.

[Ill.u.s.tration:

_a._ A gold or copper coin.

_b._ Drop of suspected solution.

_c._ A bright key.]

The salts of mercury are divided into two cla.s.ses--mercurous, where mercury is a monad element, and unites with one atom of chlorine; and mercuric salts, where it plays the part of a dyad element, or unites with two atoms. The latter of these will be taken first.

=Mercury, Pure.= (Ph. B.) _Syn._ HYDRARGYRUM PURUM. Place commercial mercury, 3 lbs., in a gla.s.s retort or iron bottle, and applying heat cause 2-1/2 lbs. of the metal to distil over into a flask employed as a receiver. Boil on this for five minutes hydrochloric acid, 3 dr., diluted with distilled water, 9 fl. dr., and having by repeated affusions of distilled water, and decantations, removed every trace of acid, let the mercury be transferred to a porcelain capsule, and dried first by filtering paper, and finally on a water bath.

=Mercuric Salts.= _Tests._ Sulphuretted hydrogen and ammonium sulphide, added in very small quant.i.ties, produce on agitation a perfectly white precipitate, which acquires successively a yellow, orange, and brownish-red colour, as more of the test is added; and, ultimately, when the test is added in considerable excess, an intensely black colour. This precipitate is insoluble in excess of the precipitant, pota.s.sium hydrate, pota.s.sium cyanide, hydrochloric acid, or nitric acid, even when boiling; but it dissolves readily and completely in pota.s.sium sulphide and in 'aqua regia' with decomposition. These reactions are characteristic.

Ammonia gives a white precipitate.

Pota.s.sium hydrate gives a reddish precipitate, turning yellow when the test is added in excess. The presence of ammonia causes the precipitate to be white, and when the solution contains much acid both reactions are imperfect.

Alkaline carbonates give a brick-red precipitate.

Pota.s.sium iodide gives a scarlet precipitate, which is soluble in excess, and in alcohol, and solution of sodium chloride.

The alkaline bicarbonates either do not disturb the solution, or only cause a slight degree of opalescence.

=Mercuric Acetate.= Hg(C_{2}H_{3}O_{2})_{2}. _Syn._ PROTACETATE OF MERCURY. _Prep._ By dissolving mercuric oxide in warm acetic acid. It crystallises in brilliant micaceous lamina, soluble in their own weight of cold water, and somewhat more soluble in boiling water. According to Robiquet, this is the basis of Keyser's antivenereal pills, which do not contain subacetate of mercury, as has been a.s.serted.

=Mercuric Bromide.= HgBr_{2}. _Syn._ PROTOBROMIDE OF MERCURY, HYDRARGYRI BIBROMIDUM. _Prep._ Two equal parts of bromine and mercury and sublime.

Soluble reddish ma.s.s; resembles the iodide in its action.--_Dose_, 1/20 to 1/8 gr.

=Mercuric Chloride.= HgCl_{2}. _Syn._ PROTOCHLORIDE OF MERCURY, PERCHLORIDE OF MERCURY, b.i.+.c.hLORIDE OF MERCURY, CORROSIVE SUBLIMATE; HYDRARGYRI PERCHLORIDUM (B. P.), HYDRARGYRI b.i.+.c.hLORIDUM (Ph. L.), SUBLIMATUS CORROSIVUS (Ph. E.), SUBLIMATUM CORROSIVUM (Ph. D.), HYDRARGYRI CHLORIDUM CORROSIVUM (Ph. U. S.), HYDRARGYRI MURIAS CORROSIVUS, L. This is the 'corrosive sublimate' of the shops.

_Prep._ 1. (Ph. L.) Mercury, 2 lbs.; sulphuric acid, 21-1/2 fl. oz.; boil to dryness, and rub the residuum, when cold, with sodium chloride, 1-1/2 lb., in an earthenware mortar; lastly, sublime by a gradually increased heat.

2. (Ph. E.) Mercury, 4 oz.; sulphuric acid, 2 fl. oz. 3 fl. dr.; pure nitric acid, 1/2 fl. oz.; dissolve, add of sodium chloride, 3 oz., and sublime as before.

3. (Ph. D.) 'Persulphate of mercury' (mercuric sulphate), 2 parts; dried sodium chloride, 1 part; triturate, &c., as before.

4. (Ph. B.) Reduce sulphate of mercury, 20 oz., and chloride of sodium, dried, 16 oz., each to fine powder, and having mixed them add black oxide of manganese, in fine powder, 1 oz., thoroughly by trituration in a mortar, place the mixture in an apparatus adapted for sublimation, and apply sufficient heat to cause vapours of perchloride of mercury to rise into the less heated part of the apparatus arranged for their condensation.

_Obs._ In preparing corrosive sublimate, as well as calomel, by the common process, the solution of the mercury is usually made in an iron pot, set in a furnace under a chimney, to carry off the fumes; and the sublimation is conducted in an earthen alembic placed in a sand bath, or in an iron pot, covered with a semi-spherical earthen head. Corrosive sublimate may also be made by the direct solution of mercuric oxide in hydrochloric acid, or by bringing its const.i.tuents together in the state of vapour. The latter plan was patented by the late Dr A. T. Thomson.

_Prop._ The mercuric chloride of commerce occurs in white, semi-transparent, crystalline ma.s.ses, of considerable density; it possesses an intense coppery taste, is soluble in about 16 parts of cold, and in 3 parts of boiling water; the boiling solution deposits its excess of salt in long white prisms as it cools; soluble in alcohol and ether, in the latter so much so that it has even the property of withdrawing it from its aqueous solutions; the addition of hydrochloric acid, ammonious chloride or camphor, increases its solubility in all these menstrua. It is decomposed by contact with nearly all metallic bodies, and in solution by various organic substances, and by exposure to light. Sp. gr. 52 (514 to 542--Liebig). It melts at about 509 Fahr., and boils and volatilises at a higher temperature.

_Tests._ The presence of mercuric chloride may, under most circ.u.mstances, be readily detected by the tests given. To distinguish it from other salts, special tests for chlorine or hydrochloric acid must be applied. If on filtering the solution, acidulating it with dilute nitric acid, and testing it with silver nitrate, a cloudy white precipitate be formed, which is insoluble in excess of the precipitant, and in nitric acid, but soluble in ammonia water, and blackened by lengthened exposure to light, corrosive sublimate is shown to be present in the substance examined.

Calomel, the only compound of mercury with chlorine besides corrosive sublimate, is an insoluble powder, which could not, therefore, be found in the filtered liquid. Calomel, or the white precipitate formed by the mercurous salt, with hydrochloric acid and the soluble chlorides, is soluble in excess of the precipitant, and is not only insoluble in liquor of ammonia, but is immediately blackened by it.

For the purpose of demonstrating the presence of corrosive sublimate in a highly coloured liquid, or one loaded with organic matter, it is necessary to agitate it for some minutes with an equal volume of ether. After repose for a short time, the ethereal solution is decanted, and allowed to evaporate spontaneously. The residuum (if any) contains the corrosive sublimate, which, after being dissolved in distilled water, is readily recognised by the above characteristics.

When the substance under examination consists of food, or the contents of the digestive ca.n.a.l, or of animal tissue, it is in general necessary to destroy the organic matter in a nearly similar way to that described under a.r.s.eNIOUS ACID. The process adopted by Devergie for this purpose consists in dissolving the substance in concentrated hydrochloric acid, and pa.s.sing a stream of chlorine through the liquid.--Flandin first carbonises the ma.s.s with 1/3 or 1/2 its weight of concentrated sulphuric acid, at 212 Fahr., and then saturates the acid in the cold, with dry 'chloride of lime,' added in fragments, a.s.sisting the action by stirring, and further adding, by degrees, as the matter thickens and becomes white, a sufficient quant.i.ty of distilled water.--La.s.saigne boils the suspected mixture for some time with a solution of sodium chloride; a method which, according to Orfila, is not sufficiently delicate to withdraw minute portions of mercury from flesh.--Millon agitates organic liquids (more especially blood, milk, &c.) in large flasks containing gaseous chlorine, which is frequently renewed.--Orfila either dissolves the matter in aqua regia, and pa.s.ses a stream of chlorine through the liquid, or he carbonises it by means of concentrated sulphuric acid, in close vessels.--Personne proceeds by a similar method, but avoids raising the temperature of the substances operated on.--Reveil employs either the last method or that of Millon. In all cases it is advisable to operate in close vessels, on account of the volatility of the b.i.+.c.hloride; Orfila's apparatus consists of a matra.s.s, provided with a bent tube, the one end of which is plunged into a jar of cold distilled water. The corrosive sublimate is found both in the volatilised matter and in the carbonised residuum, and is extracted from the latter by boiling it for 15 or 20 minutes in aqua regia.

When the organic matter has been destroyed by any of the above processes, and a colourless and filtered solution in distilled water obtained, the usual tests may be at once applied. But in this way we can only detect the presence of mercury, but are unable to decide in what way it has entered the system, although we may infer it from other circ.u.mstances. It is, therefore, absolutely necessary, in all medico-legal investigations, to previously employ ether (see _above_), in order that we may be enabled to examine the deleterious matter in its original form, or that in which it was swallowed.

_Uses, &c._ Mercuric chloride is employed as an alterative, diaph.o.r.etic, and resolvent, in the chronic forms of secondary syphilis, rheumatism, scrofula, cancer, old dropsies, numerous skin diseases, &c.; and externally, as a caustic, in cancer, and made into an ointment, lotion, or injection, in a vast number of skin diseases, ulcers, gleet, &c., and as a preventive of contagion. It acts quicker than the other preparations of mercury, and it is less apt to induce salivation; but it has been said that its effects are less apparent.--_Dose_, 1/10 to 1/4 gr., either made into a pill, or in solution. It is highly poisonous, and must be exhibited and handled with the greatest caution. Its use is contra-indicated in cases complicated with pulmonary affections or nervous derangement.

_Pois._--1. _Symptoms._ Strong coppery or metallic taste; intense pain in the mouth, pharynx, sophagus, stomach, and intestines; nausea, vomiting (often b.l.o.o.d.y), diarrha, and (sometimes) violent dysentery (these evacuations are generally more frequent than in poisoning by other metallic compounds). After a certain time there is generally an abatement of the severity of the symptoms; the circulation becomes slower, the pulse small and thready, the respiration gentle, and the skin cold; syncope then supervenes, and great general insensibility, always commencing at the pelvic extremities; and sometimes convulsions occur; the secretion of urine is generally diminished, sometimes even entirely suppressed; but the patients always urinate if the sublimate has been employed in a very diluted state, and if drinks have been administered. Death often appears to result from the shock to the nervous system, from intense exhaustion, or from mortification or intense inflammation of the primae viae. Poisoning by corrosive sublimate is distinguished from that by a.r.s.enic, by the countenance being flushed, and even swollen; whereas, in poisoning by a.r.s.enic, it is wholly contracted and ghastly, and by the whitened condition of the epithelium of the mouth.

2. _Antidotes._ White of egg, hydrated ferric sulphide or ferrous sulphide, and gluten, are each of them powerful antidotes. White of egg has proved efficacious in numerous cases. It requires the white of one egg to decompose 4 gr. of corrosive sublimate. (Peschier.) The recently precipitated protosulphuret of iron is, however, according to Mialhe, the antidote par excellence, not only to corrosive sublimate, but to the salts of lead and copper. The gluten of wheat has also been recommended (Taddei); or, what is equally efficacious, wheat flour mixed up with water. When any of the above are not at hand, copious draughts of milk may be subst.i.tuted. Iron filings have been occasionally used as an antidote.

All these substances should be taken in considerable quant.i.ties; the dose should be frequently repeated, and the general treatment similar to that in cases of poisoning by a.r.s.enic. Vomiting should be, in all cases, immediately induced, to remove, if possible, the poisonous matter from the stomach.

=Mercuric-ammonium Chloride.= HgNH_{2}Cl. _Syn._ AMMONIO-CHLORIDE OF MERCURY, AMMONIATED CHLORIDE OF MERCURY, WHITE PRECIPITATE, LEMERY'S W.

P., COSMETIC MERCURY; HYDRARGYRI AMMONIATUM (B. P.), HYDRARGYRI AMMONIO-CHLORIDUM (Ph. L.), HYDRARGYRUM PRECIPITATUM ALb.u.m (Ph. E.)

_Prep._ 1. (Ph. L.) Mercuric chloride, 6 oz.; distilled water, 3 quarts; dissolve, with heat, and when the solution has cooled, add of liquor of ammonia 8 fl. oz., frequently shaking it; lastly, wash the precipitate with water, and dry it. The formulae of the Ph. E. & D. are nearly similar.

2. Mercuric chloride and ammonium chloride, of each 1/2 lb.; water, 3 quarts; dissolve, and precipitate with solution of pota.s.sium hydrate, q. s.

_Prop., &c._ A white, inodorous, light ma.s.s, or powder; insoluble in alcohol, partially soluble in boiling water, and wholly dissolved by sulphuric, nitric, and hydrochloric acids, without effervescence. It is totally dissipated by heat. When heated with solution of potash, it exhales ammonia, and a.s.sumes a yellow colour. Used to make an ointment, which is employed in herpes, porrigo, itch, and other skin diseases, &c.; and by the lower orders as a dusting powder to destroy pediculi, an application which, from its liberal employment, is not always a safe one.

It is highly poisonous, and must not be swallowed.

=Mercuric and Ammonium Chloride.= NH_{4}Cl,HgCl_{2}. _Syn._ CHLORIDE OF MERCURY AND AMMONIUM, SAL ALEMBROTH; HYDRARGYRI ET AMMONII CHLORIDIUM, L.

_Prep._ (P. Cod.) From mercuric chloride and ammonium chloride, equal parts, triturated together. "The object in adding the ammonium chloride here is to render the corrosive sublimate more soluble in water. The action of the latter is not otherwise altered." (Redwood.) It is chiefly used for lotions and injections.

=Mercuric and Quinine Chloride.= _Syn._ CHLORIDE OF MERCURY AND QUININE; HYDRARGYRI ET QUINae CHLORIDUM, L. _Prep._ (M'Dermott.) From mercuric chloride, 1 part; quinine chloride, 3 parts; separately formed into saturated solutions with water and then mixed; the crystalline precipitate is collected and dried by a gentle heat.--_Dose_, 1/8 to 1/2 gr., made into a pill with crum of bread; daily, as an alterative in debilitated habits; or combined with opium thrice daily, to produce salivation.

=Mercuric Cyanide.= HgCy_{2} or Hg(CN)_{2}. _Syn._ CYANIDE OF MERCURY; HYDRARGYRI CYANIDUM, H. BICYANIDUM, H. CYANURETUM (Ph. U. S.), L. _Prep._ 1. (Pb. L. 1836.) Ferric ferrocyanide (pure Prussian blue), 8 oz.; mercuric oxide, 10 oz.; distilled water, 4 pints; boil for half an hour, filter, evaporate, and crystallise; wash what remains frequently with boiling distilled water, and again evaporate, that crystals may form. This is Proust's process. The formula of the Ph. U. S. is similar.

2. (Ph. D. 1826.) Prussian blue (pure), 6 parts; mercuric oxide, 5 parts; distilled water, 40 parts; as the last.

3. (Desfosses.) Pota.s.sium ferrocyanide, 1 part, is boiled for 1/4 hour with mercuric sulphate, 2 parts, and distilled water, 8 parts; the deposit is separated by filtration, and the liquid evaporated to crystallising point.

4. (Winckler.) Saturate dilute hydrocyanic acid with mercuric oxide; evaporate and crystallise. Pure.

_Prop., &c._ Heavy, colourless, inodorous, square prisms; tasting strongly metallic; soluble in 8 parts of cold water; slightly soluble in alcohol.

Those made by the first two formulae are of a pale yellow colour. It is transparent and totally soluble in water. The solution, on the addition of hydrochloric acid, evolves hydrocyanic acid, known by its smell; and a gla.s.s moistened with a solution of nitrate of silver, and held over it, gives a deposit soluble in boiling nitric acid. When heated it evolves cyanogen, and runs into globules of metallic mercury. It has been administered in some hepatic and skin diseases, and has been proposed as a subst.i.tute for corrosive sublimate. (Parent.) It has been said to act directly on the skin and bones, and to have proved useful in allaying the pain of nodes and in dispersing them. (Mendaga.) It is, however, princ.i.p.ally used as a source of cyanogen and hydrocyanic acid.--_Dose_, 1/16 to 1/4 gr. (beginning with the smaller quant.i.ty), made into pills with crum of bread, or in alcoholic solution; as a gargle or lotion, 10 gr. to water, 1 pint; as an ointment, 10 or 12 gr., to lard, 1 oz.

=Mercuric Iodide.= HgI_{2}. _Syn._ PROTIODIDE OF MERCURY, RED IODIDE OF MERCURY, IODIDE OF MERCURY, BINIODIDE OF MERCURY; HYDRARGYRI IODIDUM RUBRUM (B. P.), HYDRARGYRI IODIDUM, H. BINIODIDUM (Ph. E.), H. IODIDUM RUBRUM (Ph. D.), L. _Prep._ 1. (B. P.) Mercuric chloride (corrosive sublimate), 4; pota.s.sium iodide, 5; boiling distilled water, 80. Dissolve the mercuric chloride in 60 of water, and the pota.s.sium iodide in the remainder, and mix the two solutions. Allow to stand, decant the supernatant liquor, and collect the precipitate on a filter, wash twice with cold water, and dry at 212 F.

2. (Ph. L. 1836.) Mercury, 1 oz.; iodine, 10 dr.; rectified spirit, q. s.

(2 or 3 fl. dr.); triturate until the globules of mercury disappear, and the mixture a.s.sumes a scarlet colour, then dry it in the shade, and preserve it in a well-stoppered vessel.

3. (Ph. E.) Mercury, 2 oz.; iodine, 2-1/2 oz.; spirit, q. s.; triturate together as last, dissolve the product, by brisk ebullition, in concentrated solution of sodium chloride, 1 gall., filter whilst boiling hot, wash the crystals that are deposited as the solution cools, and dry them.

4. (Ph. D.) Mercuric chloride, 1 oz.; hot distilled water, 25 fl. oz.; dissolve pota.s.sium iodide, 1-1/2 oz.; water, 5 fl. oz.; dissolve; when the solutions are cold, mix them, collect the precipitate on a paper filter, drain it, wash it with distilled water, 10 fl. oz., and dry it at a heat not above that of boiling water.