Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 16

_Uses._ The uses of lead in the arts are well known. It enters into the composition of many important alloys (pewter, type-metal, shot-metal, solder, &c.), it furnishes us with several valuable pigments (chrome yellow, &c.), and it is extensively used in dyeing. Some of its preparations are employed in medicine.

_Ant., &c._ Administer an emetic of sulphate of zinc or sulphate of copper, and, if necessary, tickle the fauces with the finger or a feather, to induce vomiting. Should this not succeed the stomach-pump may be had recourse to. Epsom or Glauber's salts, or alum, dissolved in water, or water acidulated with sulphuric acid, followed by tea, water gruel, or barley water, are the proper antidotes, and should be taken as soon after the poison has been swallowed as possible. In poisoning by white lead, Dr Alfred Taylor recommends the administration of a mixture of sulphate of magnesium and vinegar, as preferable to the sulphate alone. When the symptoms are those of painter's colic, the treatment recommended under that head should be adopted. In paralysis arising from lead, small doses of strychnine and its preparations may be cautiously administered. A symptom of poisoning by lead is the formation of a narrow leaden blue line, from 1/20th to 1/6th of an inch wide, bordering the edges of the gums, attached to the neck of two or more teeth of either jaw. (Dr Burton.) This discoloration may often be detected or rendered more conspicuous by rinsing the mouth out with water holding a little sulphuretted hydrogen or sulphydrate of ammonium in solution. Chevallier and Rayer recommend the use of sulphurous or hepatic mineral waters, or of artificial solutions of sulphuretted hydrogen or alkaline sulphides in water, both in cases of acute and chronic poisoning by lead; but the practical success of this plan does not appear to have been in proportion to theoretical antic.i.p.ations. The moist and freshly precipitated sulphides of iron are said by their advocates to be infallible if taken sufficiently early.

=Lead in Aerated Water.= Some time since Sir Robert Christison condemned the use of syphons for lemonade, owing to the action of free tartaric acid upon lead, and the rapidity with which waters containing any free acid become charged with lead in syphons. According to Professor Miller, 00175 gr. of lead per gallon is not an unusual amount for average cistern water.

Mr John S. Thompson, however, reports to the Edinburgh University Chemical Society that, after such water has been aerated and put into a syphon, the amount of lead dissolved in it begins to rise in a rapid manner. Thus in potash water, drawn from a syphon, 00408 grain of lead per gallon was found to be present, being nearly 25 times the quant.i.ty found in the same water before it entered the syphon. Pure aerated water again drawn in a similar manner from a syphon gave 00816 gr. of lead per gallon, or exactly double the amount found in the potash water, showing at once the well-known protective action that salts of the alkalies and alkaline earths have on lead. "Although," says the 'Medical Journal,' "these results are sufficiently high and alarming; still, when the water is drawn off in small quant.i.ties at a time, as is frequently the case with invalids, the results are found to be still higher; thus, when potash water was so treated, 00455 gr. of lead per gallon was found, while aerated water, drawn off in small quant.i.ties, gave 00933 gr. of lead per gallon, showing a very marked rise in both cases. The cause of this increase in quant.i.ty of the lead appears to be owing, not so much to the lengthened period of contact between the liquid and the metal as to the fact that the nozzle of the syphon, being exposed to the atmosphere in a moist state, becomes rapidly oxidised or carbonated, and is left in the most suitable condition for entering into solution, so that, when merely small portions of the liquid are drawn off each time, a comparatively concentrated solution of lead is obtained. These results," continues the same authority, "compare accurately with those which were obtained by Messrs Savory and Moore, in examining the contents of a series of syphons of aerated water for Dr George Owen Rees, F.R.S., whose attention was drawn to the subject by detecting symptoms of lead-poisoning in himself after he had been in the habit for some time of drinking such aerated water."

=Lead, Acetate of.= Pb(C_{2}H_{3}O_{2})_{2}. _Syn._ PLUMBIC ACETATE, SUGAR OF LEAD, PLUMBI ACETAS. (B. P.) _Prep._ Litharge (in fine powder) 24; acetic acid, 40; distilled water, 20; mix the acetic acid and the water, add the litharge, and dissolve with the aid of a gentle heat, filter, evaporate until a pellicle forms, and crystallise. Drain and dry the crystal.

Acetic acid (sp. gr. 10843), 23 parts, is gently heated in a copper boiler rendered electro-negative by means of a large flat piece of lead soldered within it, and litharge (pure, and in fine powder), 13 parts, is sprinkled in; the heat is then continued, with constant stirring, until the acid is saturated, when the mother-waters of a former process, if any, are added, and the whole is heated to the boiling point, and allowed to settle until cold; the clear portion is now decanted, and evaporated in a similar vessel until the liquor has the sp. gr. 1266 or 1267, when it is run into salt-glazed stone-ware vessels (the edges of which have been well smeared with candle grease), and allowed to crystallise. The product is 38 to 38-1/2 parts of crystallised sugar of lead. It is found to be advantageous to preserve a very slight excess of acid during the boiling and crystallisation, to prevent the formation of any basic acetate the presence of which impedes the formation of regular crystals.

From litharge, 112 lbs.; acetic acid (sp. gr. 1057), 128 lbs. _Prop._ 180 to 184 lbs.

_Prop._ Pure acetate of lead forms colourless, transparent, prismatic crystals, slightly efflorescent in dry air; it is soluble in 8 parts of alcohol and in 1-1/4 part of cold water; the aqueous solution has a sweet astringent taste, and feebly reddens litmus, but turns turmeric and the juice of violets green; when gently heated, it melts in its water of crystallisation; by continuing the heat, the whole of the water is expelled, and the dry acetate obtained; at a higher temperature the salt suffers decomposition, and acetic acid, acetone, &c., is given off.

Commercial acetate of lead is in general a confused crystalline ma.s.s, somewhat resembling broken lump sugar. It is powerfully astringent and poisonous.

When pure it is completely soluble in distilled water acidulated with acetic acid forming a transparent colourless solution, "38 grains dissolved in water require for complete precipitation 200 grains measures of the volumetric solution of oxalic acid." (B. P.)

_Uses, &c._ Acetate of lead is extensively employed in dyeing and calico-printing. In _medicine_ it is used as an astringent, styptic, and haemostatic; in pulmonary, uterine, and intestinal haemorrhage, colliquative diarrha, phthisical sweats, &c. It is usually combined with morphia or opium, and with acetic acid to prevent it pa.s.sing into the state of the poisonous carbonate in the stomach.--_Dose_, 1/2 gr. to 2 gr. (Collier); 1 to 2 gr. to 8 or 10 gr., twice or thrice a day (Pereira); 3 gr. to 10 gr., every 6 or 8 hours (A. T. Thomson). _Externally_, as a collyrium, 10 gr.

to water, 8 fl. oz. (A. T. Thomson); as a lotion, 20 gr. (A. T. Thomson), 1 dr. (Collier) to water, 8 or 10 fl. oz.; as an injection, 40 gr. to rose water, 1/2 pint. The lotion is cooling and sedative, and is commonly used in excoriations, local inflammations, &c.

=Basic Acetates.= There are several of these salts, but only one is of any importance.

=Tribasic Lead Acetate or Double Plumbic Acetate, and Dioxide.= Pb(C_{2}H_{3}O_{2})_{2} 2PbO. _Syn._ SUBACETATE OF LEAD; BASIC LEAD CITRATE; GOULARD'S ACETATE OF LEAD; PLUMBI SUBACETAS (B. P.). _Prep._ Litharge, 7; acetate of lead, 10; and distilled water, 40; are boiled half an hour, and evaporated down, and allowed to crystallise out of contact with air.

Used under the form of "Plumbi subacetas liquor" v. (B. P.)

=Lead, a.r.s.e"niate of.= Pb_{3}(AsO_{4})_{2}. _Syn._ a.r.s.eNATE OF L.; PLUMBI a.r.s.eNIAS, L. _Prep._ Gradually add a solution of acetate of lead to another of a.r.s.eniate of sodium. A white, insoluble powder. Proposed as an external application in certain forms of cancer.

=Lead, Bro'mide of.= PbBr_{2}. _Syn._ PLUMBI BROMIDUM, L. _Prep._ By precipitating a solution of neutral acetate or nitrate of lead with a solution of bromide of pota.s.sium. A white, crystalline powder, sparingly soluble in water. It fuses by heat into a red liquid, which turns yellow when cold. It has been used in the same cases as iodide of lead.

=Lead, Car'bonate of.= PbCO_{3}. _Syn._ PLUMBI CARBONAS, L. _Prep._ By precipitating a cold solution of either acetate or nitrate of lead with a solution of an alkaline carbonate, observing to well wash the precipitate and dry it in the shade. This preparation is seldom employed, the commercial carbonate (WHITE LEAD) being subst.i.tuted for it. See WHITE PIGMENTS.

=Lead, Chloride of.= PbCl_{2}. _Syn._ CHLORIDE LEAD; PLUMBI CHLORIDUM (Ph.

L. 1836). _Prep._ (Ph. L. 1836). Dissolve acetate of lead, 19 oz., in boiling water, 3 pints; next dissolve chloride of sodium, 6 oz., in boiling water, 1 pint; mix the two solutions, and when cold wash and dry the precipitate. A white, crystalline powder.

Dissolve finely powdered litharge in boiling dilute hydrochloric acid, and set aside the filtered solution to cool. Brilliant colourless needles.

_Prop._ Soluble in 135 parts of cold and in 22 parts of boiling water; it melts when heated, and solidifies on cooling, forming a horn-like substance (horn lead; plumbi corneum).

_Uses, &c._ In the Ph. L. 1836, chloride of lead was ordered to be employed in the preparation of 'hydrochlorate of morphia.' Mr Tuson highly recommends it in cancerous affections, to allay pain and restrain morbid action, either in the form of a lotion or ointment.

Various mixtures of lead chlorides and oxide are employed as a white pigment under the name of 'Pattison's white.' It is prepared by rapidly mixing a boiling solution of lead chloride with an equal volume of lime water. Another similar compound is called 'patent yellow' or 'Turner's yellow.'

=Lead, Chromate of.= PbCrO_{4}. _Syn._ LEMON YELLOW, LEIPSIG YELLOW, PARIS YELLOW. _Prep._ By adding a filtered solution of acetate or nitrate of lead to a like solution of chromate of pota.s.sium, as long as the precipitate forms, which is collected, washed with water, and dried. For information respecting the manufacture of this substance on the large scale, as a colouring substance (chrome yellow), see YELLOW PIGMENTS.

=Lead, Dichromate of.= _Syn._ CHROME ORANGE, CHROME RED. PbCrO_{4}.PbO.

_Prep._ By adding to a solution of nitrate or acetate of lead a solution of chromate of pota.s.sium, to which an equivalent of pota.s.sa has been added. This compound is of a splendid scarlet colour. See RED PIGMENTS.

=Lead, Cy'anide of.= PbCy_{2}. _Syn._ PLUMBI CYANIDUM, L. _Prep._ By adding hydrocyanic acid to a solution of acetate of lead, as long as a precipitate forms, which, after being washed with distilled water, is dried by a very gentle heat, and preserved from the light and air.

Sometimes used as a source of medicinal hydrocyanic acid.

=Lead, Iodide of.= PbI_{2}. _Syn._ LEAD IODIDE; PLUMBI IODIDUM (B. P., Ph.

L. E. D.). _Prep._ (B. P.) Nitrate of lead, 4; iodide of pota.s.sium, 4; distilled water, a sufficiency. Dissolve with the aid of heat the nitrate of lead in 30 of water, and the iodide of pota.s.sium in 10 of water, mix, collect the precipitate, wash, and dry at a gentle heat.

_Prop., &c._ A rich yellow-coloured powder, soluble in acetic acid, alcohol, and boiling water; when heated, it fuses and volatilises in yellow vapour, but with a higher degree of heat, violet vapours of iodine are evolved, leaving a residuum (lead) which is wholly soluble in nitric acid.--_Dose_, 1/4 gr. to 4 gr. or more, made into a pill; as a deobstruent and resolvent, in enlargements of the cervical, axillary, and mesenteric glands, and in scrofulous affections and scirrhous tumours.

=Lead, Nitrate of.= Pb(NO_{3})_{2}. _Syn._ PLUMBI NITRAS, L. (B. P., Ph.

E. D.)

_Prep._ (Ph. D.) Litharge (in fine powder), 1 oz.; pure nitric acid, 2 fl.

oz., diluted with water, 1/2 pint; mix, apply a sand-heat, and evaporate to dryness, occasionally stirring; boil the residuum in water, 2-1/2 pints; filter, acidulate with a few drops of nitric acid, evaporate to a pellicle, and set the liquid aside to cool; lastly, dry the deposited crystals on bibulous paper, and preserve them in a well closed bottle.

(Commercial.) By dissolving white lead in dilute nitric acid, and crystallising.

_Uses, &c._ This salt is extensively used in calico printing, and in the preparation of the iodide and other salts of lead. It was formerly much esteemed in asthmas, haemorrhages, and epilepsy. It is now often used in an external application in cancer, ulcers, wounds, and various cutaneous affections. It is the basis of Liebert's celebrated 'cosmetique infallible,' and of Ledoyen's 'disinfecting fluid.' A very weak solution is an excellent application to chapped nipples, lips, hands, &c.--_Dose_, 1/2 to 1 gr.; in the form of pill or solution, washed down with a tablespoonful of water very slightly acidulated with nitric acid.

=Lead, Nitro-sac'charate of.= _Syn._ PLUMBI NITROSACCHARAS, L. _Prep._ (Dr S. E. Hoskins.) Nitric acid, 1 part; water, 19 parts; mix; in this dilute acid saccharate of lead (in fine powder) is to be dissolved, and set aside that crystals may form, which are to be dried by pressure between the folds of bibulous paper. A weak solution of the salt, acidulated with saccharic acid, has been employed by Dr Hoskins as a solvent for phosphatic calculi, with apparent success.

=Lead, Oxide of.= PbO. _Syn._ MONOXIDE OF LEAD, PROTOXIDE OF LEAD, YELLOW OXIDE OF LEAD, PLUMBI OXYDUM (B. P.) _Prep._ This substance is obtained perfectly pure by expelling the acid from nitrate of lead, by exposing it to heat in a platinum crucible; or, still better, by adding ammonia to a cold solution of nitrate of lead until the liquid becomes faintly alkaline, was.h.i.+ng the precipitate with cold water, drying it, and heating it to moderate redness for 1 hour.

_Prop., &c._ Pure protoxide of lead has a lemon-yellow colour, and is the best of all the salts of lead. It is very heavy, slightly soluble in water, and freely so in acids, particularly when in the hydrated state; the aqueous solution has an alkaline reaction; at a red heat it melts, and a.s.sumes a semi-crystalline form on cooling; in the melted state it rapidly attacks and dissolves siliceous matter, with which it unites to form gla.s.s (flint gla.s.s); when heated along with organic substances of any kind, it is easily reduced to the metallic state.

On the commercial scale, this oxide is prepared by heating the grey film or dross that forms on the surface of melted lead when freely exposed to the air. When the process is arrested, as soon as the oxide acquires a uniform yellow colour, it is called ma.s.sicot; when the heat is still further increased, until it fuses or partially vitrifies, it forms litharge of which there are several varieties. See LITHARGE, Ma.s.sICOT.

=Lead, Red Oxide of.= _Syn._ RED LEAD, MINIUM. _Prep._ This is prepared by exposing unfused protoxide of lead to the air for a long time, at a dull red heat. It is a very heavy powder, of a fine red colour, decomposed by a strong heat into protoxide of lead, and oxygen gas, which is evolved.

Somewhat uncertain in its composition, but is generally of the composition Pb_{3}O_{4} or PbO_{2}2PbO. See RED PIGMENT.

=Lead, Dioxide.= PbO_{2}. _Syn._ BINIODIDE OF LEAD, PEROXIDE OF LEAD, PUCE OXIDE OF LEAD. _Prep._ By digesting red oxide of lead in dilute nitric acid; or by infusing a mixture of protoxide of lead and chlorate of pota.s.sium at a heat a little below redness, and was.h.i.+ng the powdered ma.s.s in water; or by transmitting a current of chlorine gas through a solution of neutral acetate of lead. This oxide gives up half its oxygen at a red heat; acids also decompose it. Its chief use is in chemical a.n.a.lysis, to separate sulphurous acid from certain gaseous mixtures, which it converts into sulphuric acid, which it at the same time absorbs, forming sulphate of lead. It has recently been employed as an oxidising agent in the manufacture of the ANILINE DYES.

=Lead, Pyrolig'nite of.= Sugar of lead made with rough pyroligneous acid.

Used in dyeing, chiefly for the preparation of acetate of alumina.

=Lead, Sac'charate of.= _Syn._ PLUMBI SACCHARAS, L. _Prep._ (Dr S. E.

Hoskins.) Nitric acid, 2 parts; water, 10 parts; mix in a porcelain capsule, add of sugar, 1 part; and apply heat until reaction ceases; then dilute the liquid with distilled water, neutralise it with powdered chalk, filter, and add to the filtrate a solution of acetate of lead, as long as a precipitate (saccharate of lead) forms; lastly, collect the precipitate on a filter, wash and dry it. Used to make nitro-saccharate of lead, and as a source of saccharic acid.

=Lead, Sul'phate of.= PbSO_{4}. _Syn._ PLUMBI SULPHAS, L. This salt occurs native in transparent octohedra (lead vitriol), and is obtained in large quant.i.ties as a by-product in the preparation of acetate of aluminum for dyeing.

_Prep._ By adding dilute sulphuric acid to a solution of a soluble salt of lead. It is very sparingly soluble in water and in dilute sulphuric acid, soluble in strong hydrochloric acid and bitartrate of ammonium.

=Lead, Sul'phide of.= PbS. _Syn._ PLUMBI SULPHIDE. This occurs abundantly in nature in the form of GALENA.

_Prep._ By fusing metallic lead with sulphur or by pa.s.sing sulphuretted hydrogen through a solution of a salt of lead.

=Lead, Tan'nate of.= _Syn._ PLUMBI TANNAS, L. _Prep._ Precipitate a solution of acetate of lead with an infusion of galls, and wash and dry the precipitate. Astringent, sedative, and haemostatic.--_Dose_, 1 gr. and upwards, made into a pill. It has been highly recommended in the form of ointment and cataplasms, in bed-sores, chronic ulcers of the feet, white swellings, &c.

=Lead, Tar'trate of.= _Syn._ PLUMBI TARTRAS, L. _Prep._ By precipitating acetate of lead, by tartrate of ammonium, was.h.i.+ng and drying.

=LEAD DUST.= _Syn._ PULVIS PLUMBI, PLUMb.u.m DIVISUM, L. _Prep._ By melting new lead, adding bruised charcoal, mixing with violent agitation, which must be continued until the metal 'sets,' and then pounding and was.h.i.+ng away the charcoal. Used by potters.