A Cyclopædia of Practical Receipts, &c. Volume II (part 12)

“It is coming into great use in India, and is carried out with great attention to detail. In those European stations where water is not procurable Mr Moule’s invention has been a boon of great value, and medical officers say that nothing has been done in India of late years which has contributed so much to the health and comfort of the men. The plan of separating the urine from the fæces has been strongly advocated by Dr Cornish, of Madras, and would, no doubt, be attended with great advantages in India if there are means of disposal of the urine. The chief difficulty in the European barracks in India is felt during the rainy season, when the mixed excreta and earth cannot be kept sufficiently dry. In the case of natives of India, however, a serious difficulty arises in the use of the earth system, in consequence of the universal use of water for ablution after using the closet. Every native takes with him a small vessel holding ten to twenty ounces of water, so that a large amount of fluid has to be disposed of. The usual earth closet does not suffice for this. Mr Charles Turner, C.E., of Southampton, has contrived a closet suitable for the native family; it is unfortunately too costly, and possibly a simple iron box, with a pipe to carry off the urine and ablution water, would be better suited for the poorer classes.”

e. Captain Lieurnur’s pneumatic plan. This process, the invention of a Dutch engineer, is in use at Amsterdam, Leyden, Drodrecht, and a few other Continental towns. It is also known as the ‘aspiration plan.’ Its outlines are as follows:—“The pipes and, tubes leading from the various water-closets and privies peculiar to the system are connected with street mains, which mains again communicate with underground horizontal cast-iron cylinders or tanks, these tanks being directly connected with a powerful air-pump worked by steam. Communication between the main and the tanks, as well as between the tanks and the pump, can be made or broken by means of stopcocks. Hence it follows that when access is allowed between one of the tanks and the air-pump, this latter will, when put into action, produce a vacuum in the tank, and if the stopcock of the main leading to the tank be then opened, the contents of all the privies and water-closets, the pipes of which run into the main, will be removed by being swept into the tank by pneumatic force. In this manner each tank is treated in succession. Similarly the sewage is carried to the large reservoirs of a manure manufactory. It is here mixed with a little sulphuric acid to prevent the formation of ammonia, and being evaporated down in vacuo becomes converted, when sufficiently dry, into poudrette. In Lieurnur’s process all deodorants are dispensed with, and its mixture with water is prevented by means of porous drain pipes laid above the sewers, by which contrivance the subsoil water is kept out of the sewers.

Sewage, Utilisation of. “Mr Peregrine Birch read before the Institution of Surveyors a paper on ‘The Use of Sewage by Farmers,’ which embodied some facts that deserve to be noticed, as bearing on a question we have repeatedly discussed. It appears that there are at the present time ‘upwards of one hundred owners and occupiers of land in Great Britain who use sewage for the sake alone of what they can get out of it by agricultural means.’ Of these ‘more than sixty are tenant farmers, who continue to use it although they have, annually at least, the option of ceasing to do so,’ It seems five out of six of the tenant farmers purchase the sewage they employ, so that their adhesion to the method proves conclusively that it pays. Nearly four thousand acres of land are under regular cultivation with sewage. Mr Birch is of opinion that ‘advocates of sewage precipitation processes should not regard sewage farmers as their rivals, for a chemical process might be very largely used with advantage when farmers are being persuaded or taught to use sewage. But this should be the distinct aim of all cultivation, for there is no chemical process that could not be worked to greater advantage during two months of the year than twelve, or applied to a small quantity of sewage at less cost than to a large.’ Our primary interest is to see the utilisation of sewage generally adopted; the method employed must be determined by experience on the grounds of cheapness and expediency.”—Lancet.

SHAD′DOCK. A large species of orange, the fruit of Citrus Decumana (Linn.).

SHAGREEN′. This is prepared from the skins of the horse, wild ass, and camel, as follows:—The skin, freed from epidermis and hair by soaking in water, and, after dressing with the currier’s fleshing-knife, is sprinkled over, whilst still wet and stretched, with the seeds of a species of chenopodium, which are imbedded in it by strong pressure, and in this state it is dried; the seeds are then shaken off, and the surface rubbed or shaved down, nearly to the bottom of the seed-pits or indentations; it is next soaked in water, by which the skin swells, and the recently depressed surface rises into a number of minute prominences; it is, lastly, dyed and smoothed off. Black is given to it with galls and copperas; blue, with a solution of indigo; green, with copper filings and sal ammoniac; and red, with cochineal and alum. Shagreen was formerly very extensively used for covering the cases of watches, spectacles, surgical instruments, &c.

SHALLOT′. Syn. Eschalot. The Allium ascalonicum (Linn.), a plant allied to the onion, the bulb of which is much used as a sauce or pot-herb.

SHAMPOO′ING. A practice common in the East, having for its object the increase or restoration of the tone and vigour of the body, or the mitigation of pain. It is applied either in the bath or immediately after quitting it, generally the latter, and consists in pressing and kneading the flesh, stretching and relaxing the knee-joints, and laboriously brushing and scrubbing the skin.

SHARPS. See Flour.

SHA′VING. The following are Mr Mechi’s instructions for this, to many persons, troublesome operation:—Never fail to well wash your beard with soap and cold water, and to rub it dry, immediately before you apply the lather, of which the more you use the easier you will shave. Never use warm water, which makes a tender face. Place the razor (closed, of course) in your pocket, or under your arm, to warm it. The moment you leave your bed is the best time to shave. Always put your shaving-brush away with the lather on it.

The razor (being only a very fine saw) should be moved in a sloping or sawing direction, holding it nearly flat to your face, care being taken to draw the skin as tight as possible with the left hand, so as to present an even surface and throw out the beard. The practice of pressing on the edge of a razor in stropping generally rounds it; the pressure should be directed to the back, which must never be raised from the strop. If you shave from heel to point of the razor, strop it from point to heel; but if you begin with the point, then strop from heel to point. If you only once put away your razor without stropping or otherwise cleaning the edge, you must no longer expect to shave well, the soap and damp so soon rust the fine teeth or edge. A piece of plate leather should always be kept with the razors.

SHAVING FLUID. See Essence of Soap.

SHAWLS, To Scour. Scrape one pound of soap into thin shavings, and let it be boiled with as much water as will convert into a thin jelly. When cold, beat it with the hand, and mix with it three tablespoonfuls of oil of turpentine, and one of hartshorn. Let the shawl be well washed in this mixture, and afterwards rinsed in cold water, so as to get rid of all the soap.

Next let the shawl be rinsed in salt and water, then wring out the water from it, and fold it between two sheets, being careful not to allow two folds of the shawl to lie together; finally mangle, and iron with a cool iron.

SHEEP. Syn. Ovis, L. The Ovis aries, an animal domesticated almost everywhere. Its flesh supplies us with food, its skin with leather, its fleece with wool, and its intestines with catgut. Its fat (sevum) is officinal. See Mutton, Suet, &c.

Sheep Washes. 1. Arsenious acid in powder, carbonate of potash, of each 6 oz.; water, 14 gall. Boil together for half an hour.

2. Arsenious acid in powder, soft soap, and carbonate of potash, of each 6 oz.; sulphur, 4 oz.; bruised hellebore root, 2 oz.; water, 14 gall. Boil the ingredients in a portion of the water for half an hour, or until the arsenic is dissolved, then add the remainder of the water, and strain through a coarse sieve. Mr Youatt says:—“More care than is usually taken should be exercised in order that the fluid may penetrate to every part of the skin, and which should be ensured by a previous washing in soap and water. The arsenic that necessarily remains about the wool when the water has dried away would probably destroy the acari as fast as they are produced. When a greater quantity of arsenic has been used, or the sheep has been kept too long in the water, fatal consequences have occasionally ensued.”

3. A sheep-dipping composition employed on the Continent is:—Arsenious acid, 1 lb.; sulphate of zinc, 10 lbs.; dissolved in 25 gallons of water.

4. The Australian sheep farmers use a weak solution of bichloride of mercury (1 oz. of the bichloride to 4 gall. of water).

5. Water, 40 parts, at the temperature of 50° to 57° C.; to this add 1 part of soluble glass (the soluble silicates). This is recommended as a very efficient and perfectly safe sheep wash by Messrs Baerle and Co., of Worms. In washing the sheep with this preparation care should be taken to cover the eyes of the animal with a bandage, to perform the washing with the solution instantaneously, and to remove the surplus with tepid water.

“Yards into which newly clipped sheep are to be turned should be previously cleared of all green food, hay, and even fresh water; if perfectly empty they are still safer. When the dipping is finished they should be cleaned, washed, and swept, and any of the unused dipping solution at once poured down the drains. Dipped sheep should remain, if possible, in an open exposed place, as on a dry road, or in a large open yard. Over-crowding should be avoided, and every facility given for rapid drying, which is greatly expedited by selecting for the operation fine, clear, drying weather. On no account should sheep be returned to their grazings until they are dry, and all risk of dripping over.

SHELL-FISH. The common name for the Crustacean and Molluscous animals that are used for food. ‘Shell-fish’ are extremely liable to disturb the functions of the stomach and bowels. The oyster (Ostrea edulis), and the cockle (Cardium edule), are, perhaps, the least objectionable. The crab (Cancer pagurus), the crayfish (Astacus fluvialis), the lobster (Homarus vulgaris), the mussel (Mytilus edulis), the prawn (Palæmon serratus), the periwinkle (Littorina littorea), and the shrimp (Crangon vulgaris), with the exception of the claws of the first three, are always suspicious, particularly in hot weather, and often absolutely poisonous. We have seen the most alarming, nay, fatal symptoms, follow the use of mussels, even amongst those habitually accustomed to take them; whilst it is a well known fact that the luscious bodies of the crab and lobster have too often formed the last supper of the epicure. See Oyster, &c.

SHEL-LAC. See Lac.

SHELLS (Prepared). Syn. Testæ præparatæ (Ph. L. 1836), L. Prep. (Ph. L. 1836.) Wash oyster-shells (OSTRÆ—Ph. L.) with boiling water, having previously freed them from extraneous matters; then prepare them in the manner directed for chalk. The product is similar in constitution and properties to prepared chalk.

Shells, To Polish. 1. The surface of the shell should be first cleaned by rubbing it over with a rag dipped in hydrochloric acid, till the outer dull skin is removed. It must be then washed in warm water, dried in hot sawdust, and polished with chamois leather. Those shells which are destitute of a natural polished surface, may be either varnished or rubbed with a mixture of tripoli powder and turpentine applied by means of a wash-leather, after which fine tripoli alone should be used, and, finally, a little olive oil, the surface being brought up with the chamois leather as before.

2. “The shells are first boiled in a strong solution of potash, then wound on wheels, sometimes through one strata to show an underlying one, then polished with hydrochloric acid and putty powder. In this operation the hands are in great danger. Shell grinders are generally almost all cripples in their hands. (Spon.)

SHER′BET. [Pers.] A cooling drink, used in the East, prepared with the juices of fruit, and water, variously sweetened and flavoured. The word has been, of late years, commonly employed in these countries in a similar manner. See Lemonade, Orangeade, and Powders.

SHER′RY. Syn. Sherry wine, Sherris; Vinum Xericum (Ph. L.), Vinum album (Ph. E.), Vinum album Hispanicum (Ph. D.), L. This is the only wine ordered in the British Pharmacopœias. See Wines.

SHERRY-COBBLER. Prep. (Redwood.) Half fill a tumbler with clean pounded ice; add a table-spoonful of powdered white sugar, a few thin slices of lemon with the peel (or some strawberries or other similar fruit, bruised), and a wine-glassful or more of sherry wine; mix them together (lightly), and as the ice melts, suck the liquor through a straw (or a small tube of silver or glass).

Obs. A favourite American drink; very refreshing in hot weather.

SHIN′′GLES. Syn. Zoster, Herpes zoster, Herpes zona, L. A local variety of herpes or tetter, remarkable for forming a kind of belt round or partly round some part of the trunk of the body, chiefly the waist or abdomen. See Tetters.

SHODDY. The epithet (we believe of American origin) is applied to the old, used-up wool and cloth, fraudulently mixed with fresh woollen fabrics. A plan for the examination of a fabric suspected of containing shoddy has been given by a German chemist, Herr Schlesinger, and is as follows:—Examine it with the microscope and note if it contains cotton, silk, or linen, as well as wool. If so dissolve them by ammoniacal solution of copper. A qualitative examination is thus obtained. Then direct attention to the wool. In shoddy both coloured and colourless fibres are often seen, the fibres having been derived from different cloths which have been partially bleached; the colouring matter, if any, instead of consisting of one pigment, will be composed of two or three different kinds, such as indigo, purpurin, or madder. Again, the diameter of the wool is never so regular as in fresh wool, but is seen to vary suddenly or gradually in diameter, and suddenly widens again with a little swelling, and tapers off again, besides which the cross markings or scales are almost always absent. When shoddy-wool is placed in liquor potassæ it is much more speedily attacked than new wool.

SHOT METAL. Prep. From lead, 1000 parts; arsenic, 3 parts. When the lead is coarse, 6 to 8 parts of metallic arsenic are required to fit it for this purpose.

SHOW BOTTLES. The large ornamental carboys and jars filled with coloured liquids, and displayed in the shop-windows of druggists, may be noticed under this head. They are striking objects when the solutions they contain are bright and of a deep pure tint, especially at night, when they are seen by transmitted light. The following formulæ for the solutions have been recommended by different persons:—

Amber. From dragon’s blood (in coarse powder), 1 part; oil of vitriol, 4 parts; digest, and, when the solution is complete, dilute the mixture with distilled or soft water, q. s.

Blue.—a. From blue vitriol, 2 oz.; oil of vitriol, ⁄2 oz.; water, 1 pint.—b. A solution of indigo in sulphuric acid, diluted with water, q. s.—c. A solution of soluble Prussian blue in either oxalic or hydrochloric acid, slightly diluted, and afterwards further diluted with water to the proper shade of colour.

Crimson.—a. From alkanet root, 1 oz.; oil of turpentine, 1 pint. Used chiefly for the bull’s eyes of lamps.—b. As PINK (b), below.

Green.—a. From sulphate of copper, 2 oz.; bichromate of potash, 1 dr., or q. s.; water, 1 pint.—b. A solution of sulphate of copper, 2 oz.; chloride of sodium, 4 oz.; water, 1 pint, or q. s.—c. A solution of distilled verdigris in acetic acid, diluted with water, q. s.—d. Dissolve blue vitriol in water, and add nitric acid until it turns green.

Lilac.—a. Dissolve crude oxide of cobalt (zaffre) in nitric or hydrochloric acid, add sesquicarbonate of ammonia, in excess, and afterwards sufficient ammonio-sulphate of copper to strike the colour.—b. As the purple, but more diluted.

Magenta. Acetate of rosaniline, dissolved in water, q. s.

Olive. Dissolve sulphate of iron and oil of vitriol, equal weights, in water, and add of nitrate of copper, q. s. to strike the colour.

Orange.—a. A solution of bichromate of potash in water, either with or without the addition of some hydrochloric or sulphuric acid.—b. Dissolve gamboge or annotta in liquor of potassa; dilute with water, and add a little spirit.

Pink.—a. To a solution of chloride or nitrate of cobalt, in water, add sesquicarbonate of ammonia, q. s. to dissolve the precipitate at first formed.—b. From madder (washed with cold water), 1 oz.; sesquicarbonate of ammonia, 4 oz.; water, 3 pints; digest, with agitation, for 24 hours, then dilute with more water, and filter.

Purple.—a. A solution of sulphate of copper, 1 oz., in water, 1 quart, or q. s., with the addition of sesquicarbonate of ammonia, 1⁄2 oz.—b. To the last add a sufficient quantity of the first pink (above) to turn the colour.—c. To an infusion of logwood, add carbonate of ammonia or of potassa, q. s.—d. Sugar of lead, 3 oz.; powdered cochineal, 1 dr.; water, q. s.—e. Add sulphate of indigo, nearly neutralised with chalk, to an infusion of cochineal, till it turns purple.

Red.—a. Dissolve carmine in liquor of ammonia, and dilute with water.—b. Digest powdered cochineal in a weak solution of ammonia or of sal ammoniac, and afterwards dilute with water.—c. Add oil of vitriol, 4 oz., to water, 1 gall., and digest dried red rose leaves, 8 oz., in the mixture for 24 hours.—d. Dissolve madder lake in a solution of sesquicarbonate of ammonia, and dilute the solution with water.

Violet. To a solution of nitrate of cobalt in a solution of sesquicarbonate of ammonia, add solution of ammonio-sulphate of copper, q. s. to strike the colour.

Yellow.—a. A solution of sesquioxide or rust of iron, ⁄2 lb., in hydrochloric acid, 1 quart, diluted with water.—b. To a strong decoction of French berries add a little alum.—c. A simple solution of chromate or bichromate of potash in distilled water.—d. A solution of equal parts of nitre and either chromate or bichromate of potash, in water.

Obs. Most of the above require filtering, which should be done through powdered glass, placed in a glass funnel, and never through paper. They usually need a second filtration, after being exposed to the light for some weeks; hence it is convenient always to make a little more of them than is required to fill the bottle, as several of them, when diluted after filtration, become again turbid. Distilled water or filtered rain water should be used.

SHRIMP. See Shell-fish.

SHRUB. A species of concentrated cold punch, prepared with lemon juice, spirit, sugar, and water. When the word is used in its unqualified form, RUM SHRUB is alluded to.

Shrub, Brandy. Prep. 1. Take of brandy, 1 gall.; orange and lemon juice, of each 1 pint; peels of 2 oranges; do. of 1 lemon; digest for 24 hours, strain, and add of white sugar, 4 lbs., dissolved in water, 5 pints; in a fortnight decant the clear liquid for use.

2. As RUM SHRUB (below), but using brandy.

Shrub, Lemon. Syn. Lemonade shrub. Concentrated lemonade, either with or without the addition of a little spirit. Used to make lemonade or lemon sherbet.

Shrub, Punch. Concentrated punch, made with equal parts of spirit and water. Used to make punch.

Shrub, Rum. Prep. 1. As BRANDY SHRUB, but substituting rum for brandy.

2. Take of rum, at proof, 34 gall. (or, if of any other strength, an equivalent quantity); essential oils of orange and lemon, of each 2 oz., dissolved in rectified spirit, 1 quart; good lump sugar, 300 lbs.; dissolved in water, 20 galls.; mix well by ‘rummaging,’ and gradually and cautiously add of Seville orange juice, or of a solution of tartaric acid in water, q. s. to produce a pleasant but scarcely perceptible acidity; next ‘rummage’ well for 15 minutes, then add sufficient water to make the whole measure exactly 100 galls., and again ‘rummage’ well for at least half an hour; lastly, bung the cask down loosely, and allow it to repose for some days. In a fortnight, or less, it will usually be sufficiently ‘brilliant’ to be racked. The product is 100 galls., at 66 u. p.

Obs. Rum shrub is the kind in the greatest demand, and that having a slight preponderance of the orange flavour is the most esteemed. If wholly flavoured with lemon it is apt to acquire a kind of ‘dead’ or ‘musty’ flavour by long keeping. The substitution of a few gallons of brandy for a portion of the rum, or the addition, after racking, of about 1 oz. each of bruised bitter almonds, cloves, and cassia, the peels of about 2 dozen oranges, and a ‘thread’ of the essences of ambergris and vanilla, render it delicious.

SIAL′OGOGUES. Medicines which increase the flow of saliva. Mercurials and pellitory of Spain belong to this class.

SICK′NESS. Nausea and vomiting frequently arise from the use of improper food, and other articles which offend the stomach; at other times it is symptomatic of some disease, as colic, cholera, dyspepsia, head affections, incipient fever, &c.; in which case the primary affection should be attended to. Nausea lowers the pulse, contracts the small vessels, occasions cold perspiration, severe rigors, and trembling; and diminishes, as long as it lasts, the actions, and even the general powers, of life. The act of retching, and vomiting more especially, on the contrary, rouses rather than depresses, puts to flight all the preceding symptoms, and often restores the system to itself.

The best remedies or palliatives in these affections are effervescing saline draughts, either with or without the addition of a few drops of tincture of henbane, or tincture of opium. A glass of genuine lemonade, iced, or a spoonful of crushed ice in a wine-glassful of mint water, is also very serviceable. Pepsin (Bullock and Reynolds) and oxalate of cerium are said to be most valuable remedies in the sickness of pregnancy. See Draughts, Pregnancy, Sea sickness, &c.

SIFT′ING is to pulverulent substances what filtration is to liquids; but in this case the medium through which the substance passes is, usually, of a simpler and coarser description. Sieves are commonly employed for the purpose, which are fitted with silk or brass-wire gauze for fine purposes, and horsehair cloth, or wire netting, for coarser ones. Drum sieves are such as are furnished with covers and an enclosed space to receive the fine powder that passes through, by which dust and loss are prevented.

SIGHT. See Vision.

Sight, Effect of Gaslight on. The German Minister of Instruction has recently issued a report on the influence of gaslight on the eye. The conclusion arrived at in this report—the result of frequent conference with well-known physicians—is that no evil results follow a moderate use of gas, if the direct action of the yellow flame on the eye is prevented. For this purpose screens or shades are employed. Very great objections, however, exist to the use of zinc or lead shades, most evils affecting the eye being traceable to them. Their use, it is said, inevitably tends to blindness or inflammation, and other harmful effects. The milky-white glass shade is the best, as it distributes the light and has a grateful effect on the eyes. The burner should not be too close to the head, as congestions of the forehead and headaches result from the radiated heat. The glass plate below the gas, employed in some places, is especially useful for the purpose, as it causes an equal distribution of the light—necessary where a number are working at one burner—prevents the radiation of heat, and tends to a steady illumination by shielding the flames from currents of air. In cases of highly-inflamed eyes, dark-blue globes can be very beneficially employed. With precautions of this kind no evil effects from the burning of gas need be feared.

SIG′NATURES (Fac-similes of). These may be readily obtained as follows:—

1. Let the name be written on a piece of paper, and, while the ink is still wet, sprinkle over it some finely-powdered gum Arabic, then make a rim round it, and pour on it some fusible alloy in a liquid state. Impressions may be taken from the plates formed in this way, by means of printing ink and the copper-plate press.

2. By the use of transfer ink and lithography.

SILBER LIGHT. This light is thus described in ‘Dingler’s Polytechnic Journal,’—This mode of illumination is recommended where gas cannot be had.

The material used is oil, which is converted into gas before combustion takes place, whereby the combustion of the wick is greatly lessened (one wick may last a year); the accumulation of impurity is obviated, and the prevention of smell completely effected. The light is regular and uniform, and of a white colour. The light, with a burner 1⁄4 inch wide, is equal to that of 28 sperm candles, each consuming 120 gr. per hour, and with one 1⁄4 inch wide a light is obtained equal to 50 such candles.

The burning apparatus consists of a row of concentrically enclosed double cylinders, perpendicularly arranged at definite intervals. The innermost cylinder contains the wick between its two walls, the hollow space in the interior serving to convey fresh air to the interior of the flame. The second cylinder conveys air to the outer side of the wick, and the third contains oil, and is in direct communication with both wick and reservoir. The mouths of all these chambers have a dome-shaped head, and form a suitable opening in this; the gas streams forth in such a manner that it comes in contact with a current of air, and thus a complete combustion is attained.

According to the nature of the oil burnt the construction is somewhat varied in its minor details. Rape oil or light hydrocarbon oils are mentioned.

SIL′ICA. SiO2. Syn. Silicic anhydride, Silicic acid, Silex, Siliceous earth†, Earth of flints†. This exists in quartz and rock crystal in a nearly pure state. The sands of rivers and the sea-shore, flint, and almost all the scintillating stones, chiefly consist of it.

Silica occurs under two conditions—the crystalline and the amorphous. The former variety has a sp. gr. of 2·642; the amorphous of 2·2-2·3. Some of our well-known native gems and precious stones consist almost wholly of one of the above forms of silica. In agate and calcedony the two varieties are combined. Amethyst is silica, coloured purple by ferric oxide. Onyx is formed of calcedony arranged in layers of different colours. Cornelian is a red or brown variety of silica coloured with ferric oxide, whilst opal is amorphous silica combined with varying quantities of water. Silica is present in the stems of certain plants, such as wheat, many grasses, to which the shining appearance of the stems is due, &c. The Italians polish marble with the ashes of burnt straw, the usefulness of which for such a purpose depends upon the silica contained in the straw; for similar reasons the Dutch rush is thus employed. Silica also occurs in solution in many natural waters. In the geysers, or boiling springs of Iceland, it exists in large quantity.

It may be obtained in a state of absolute purity by passing gaseous fluoride of silicon into water, collecting the resulting gelatinous precipitate on a calico filter, washing it with distilled water, drying it, and heating it to redness. Another method is to precipitate a solution of silicate of soda or potassa (soluble glass) with dilute hydrochloric acid, and to treat the precipitate as before.

Nearly pure silica may also be procured by heating colourless quartz to redness, and plunging it into cold water, by which treatment the quartz is rendered so friable as to be easily reducible to fine powder. Ordinary flints, subjected to this method, are found to yield silica in a condition approaching to purity. Amorphous silica is much more easily attacked by solvents than the crystalline variety. The artificial forms of silica are all amorphous.

The test for a silicate consists in fusing the suspected body with sodic or potassic carbonate, heating the residue with acid, and evaporating to dryness. If the residue be then treated with hot water the silica remains undissolved in the form of a white powder, which will yield a colourless bead when fused with sodic carbonate upon a piece of platinum foil before the blowpipe flame. If silica be fused with borax it becomes slowly dissolved, forming a clear, colourless bead.

Chapman contests Plattner’s opinion that, when silicates are fused with phosphor salt, the ‘silica skeleton’ that results is especially due to the presence of alkalies or earthy bases.

Chapman says: “It is true enough that silicates in which these bases are present exhibit the reaction; but as other silicates—practically all, indeed—exhibit the reaction also, the inference implied in the above statement is quite erroneous.

“The opalescence of the glass arises entirely from precipitated silica.

“If some pure silica (or a silicate of any kind), in a powdered condition, be dissolved before the blowpipe flame in borax until the glass be saturated, and some phosphor salt be then added, and the blowing be continued for an instant, a precipitate of silicate will immediately take place, the bead becoming milky white (or, in the case of many silicates, opaque) on cooling. This test may be resorted to for the detection of silica in the case of silicates, which dissolve with difficulty in phosphor salt alone, or which do not give the pronounced ‘skeleton’ with that reagent.”

Prop., &c. A fine, white, tasteless, infusible powder, insoluble in all acids, after being heated, except the hydrofluoric; requires the heat of the oxyhydrogen blowpipe for its fusion; approaches the precious stones in hardness; soluble in strong alkaline solutions; its salts are called SILICATES. Sp. gr. 2·66. See Glass, Glass, Soluble, &c.

Silica, Hydrates of. By pouring a dilute solution of sodium silicate into a considerable excess of hydrochloric acid the whole of the silica is retained in solution, together with the chloride of sodium formed by the action of the hydrochloric acid upon the soda. By subjecting this solution to dialysis (see DIALYSIS) the hydrochloric acid and chloride of sodium are removed, whilst the hydrate of silica is left behind, in solution, in the dialyser. Graham recommends a stratum of the liquid four tenths of an inch in depth, to be subjected for four or five days to dialysis, the water in the outer vessel to be changed every twenty-four hours.

If the solution so obtained be carefully evaporated down in a flask, and any drying of the silicic acid at the edges of the liquid being prevented, a solution may be obtained containing 14 per cent. of silica.

The solution has a very feebly acid reaction, and is without taste or colour. It cannot be preserved in the liquid state for more than a very few days, even in well-closed vessels, but becomes converted into a transparent gelatinous mass, which separates from the water. Hydrochloric acid, as well as small quantities of caustic potash or soda, retard the coagulation.

When the solution is evaporated in vacuo at 59° F. over sulphuric acid, a lustrous transparent glass is left behind, which consists of 22 per cent. of water, which closely accords with the formula SiO2H2O.

By the action of moist air upon silicic ether a transparent glassy hydrate was obtained by Ebelmen, to which this chemist assigned the formula 2SiO2,3H2O. Two hydrates of silica were obtained by Fuchs, one having the formula 3SiO2,H2O, the other, 4SiO2,H2O.

Silicic Chloride. Syn. Silicic tetrachloride. (SiCl4.) This compound is rarely, if ever, obtained by the direct method, viz. by heating silicon in chlorine, but by the following indirect process:—A paste is made of finely divided silica, oil, and charcoal, and heated in a covered crucible. The fragments of the charred substance (consisting of silica and carbon) are then placed in a porcelain tube, which is raised to a red heat in a furnace, and during the ignition of the fragments a current of dry chlorine is passed into and over them; the silicic chloride which is thus formed being made to distil over into a bent tube surrounded by a freezing mixture of ice and salt, whereby it becomes condensed.

Silicic chloride is a very voluble and strongly fuming gas, transparent and colourless, with an irritating and pungent smell. It is immediately decomposed by water into hydrochloric acid and hydrated silica, which deposits in the vessel.

Silicic Fluoride. Syn. Silicic tetrafluoride. (SiF4.) This gas is best prepared by heating in a capacious flask or retort equal parts of finely powdered fluorspar and white sand, or glass with ten or twelve times their weight of strong sulphuric acid. This gas must be collected over mercury, and in jars that are free from the least trace of moisture.

Silicic fluoride is a colourless gas, with a very pungent odour, fuming strongly in the air, and neither burning nor supporting combustion. Faraday succeeded in liquefying it under great pressure, and Natterer states that at a temperature of -220° F. it may be solidified. By water it is partially decomposed and partially dissolved, yielding silicic acid and hydrofluosilic acid.

With twice its volume of ammoniacal gas silicic fluoride combines to form a crystalline volatile. Silicic hydride has an acid reaction.

Silicic Hydride. (H4Si?) To procure this gas silicide of magnesium is decomposed with cold diluted hydrochloric acid.

The silicide of magnesium may be prepared as follows:—Mix intimately 40 parts of fused magnesic chloride, 35 of dried sodic silico-fluoride, and 10 of fused sodic chloride; these are mixed in a warm, dry tube, with 20 parts of sodium in small fragments, and thrown into a red-hot Hessian crucible, which is immediately covered, the operation being finished when the vapours of sodium cease to burn.

Silicic hydride becomes spontaneously ignited in the air, and in doing so gives off white fumes, which consist of amorphous silica (SiO2). A cold body, such as a piece of porcelain or glass, introduced into the flame, becomes covered with a brown deposit of reduced silicon. Passed into solutions of cupric sulphate, argentic nitrate, and palladium chloride, this gas throws down the metals, in most cases combined with silicon.

SILICOFLUORIC ACID. See Fluosilicic acid.

SIL′ICON. Si. Syn. Silicium. An elementary substance forming the base of silica.

This element was first obtained by Sir Humphry Davy, by acting upon silica with potassium. It is now procured much more easily by the decomposition of silico-fluoride of potassium, at an elevated temperature, with potassium or sodium. By heating a mixture of fluorspar and ground flints with sulphuric acid a gaseous tetra-fluoride of silicon is formed, which, being partially soluble in water, yields an acid solution of the tetra-fluoride. Caustic potash is then added to the acid solution of the tetra-chloride until it becomes neutralised, and the sparingly soluble silico-fluoride of potassium thus formed is thoroughly dried and mixed in a glass or iron tube with eight or nine tenths of its weight of potassium or half its weight of sodium, and heated. The following equation explains the reaction that takes place:

2KF,SiF4 + 2K2 = Si + 6KF.

The resulting mass, consisting of potassic fluoride, and reduced silicon in partial combination with the excess of potassium, is treated with cold water, when a copious evolution of hydrogen gas ensues, owing to the decomposition of the water by the excess of potassium. The potassic fluoride is got rid of by washing with cold water, its entire removal being indicated by the water ceasing to have an alkaline reaction on test paper, whilst amorphous silicon is left behind in the form of a brown powder.

Another method by which silicon may also be procured is by passing the vapour of silicic chloride over heated potassium or sodium, placed on a porcelain tray in a glass tube. In this operation it is advisable to protect the lining of the tube with thin plates of mica.

The silicon obtained by the above processes is known as amorphous silicon, and, as already stated, occurs as a brown powder. It is dull in colour, and, being heavier than water, as well as insoluble in it, sinks in that fluid. It is a non-conductor of electricity, is unaffected by nitric or sulphuric acid, but dissolves readily in hydrofluoric acid, and in a warm solution of caustic potash. It burns with great brilliancy when heated in air or oxygen, and becomes converted into silica, which, owing to the great heat of combustion, fuses, and thus forms a superficial crust over the unburnt silicon. A crystalline variety of silicon may also be procured by heating the brown amorphous silicon, already described, intensely in a platinum crucible, with exclusion of air. This crystalline silicon so obtained is much darker in colour than the amorphous, and also considerably denser; besides which it differs widely in properties from the latter. It will not take fire if heated strongly in the air or oxygen, even if before the blowpipe flame. Its density is such that it sinks in strong sulphuric acid, and hydrofluoric acid fails to dissolve it, although it is soluble in a mixture of hydrofluoric and nitric acids. It does not become oxidised, even if fused with potassic nitrate or chlorate, unless a white heat is obtained, when it burns brilliantly, giving rise, on so doing, to the formation of silica.

In addition to the above, a graphitoid form of silicon, occurring in plates, has been described by Deville and Wöhler. These chemists obtained this last modification from an alloy of silicon and aluminium, which was treated in succession with boiling hydrochloric and hydrofluoric acids. The plates of silicon which are left have a metallic lustre, and a sp. gr. of 2·49. The graphitoid bears a great resemblance in properties to the crystalline silicon. It is a conductor of electricity. Like the crystalline variety, it dissolves in a mixture of hydrofluoric and nitric acids, although slowly, but, unlike the crystalline, it undergoes no change when heated to whiteness in a current of oxygen.

Deville states that silicon requires a temperature between the melting points of iron and steel to fuse it. He effected its fusion in a platinum crucible lined with lime, the platinum crucible being then placed in a clay crucible, which was then exposed to intense heat in a wind furnace.

By passing the vapour of silicic chloride over pure aluminium, placed on a porcelain tray, and raised to an intense heat, the aluminium becomes volatilised as aluminic chloride, whilst the silicon remains behind in crystals possessing a reddish lustre. These crystals occur in regular six-sided prisms, terminated by three-sided pyramids, derived from the octohedra, and are so hard that glass may be cut by them, in the same way as by the diamond.

With oxygen silicon forms only one oxide, silica, described above.

SILK. As an article of clothing, as far as “roundness of fibre, softness of texture, absence of attraction for moisture, and power of communicating warmth, are concerned, silk is greatly superior to both linen and cotton; moreover, it gives the sensation of freshness to the touch which is so agreeable in linen. But, with all these advantages, silk (when worn next the body) has its defects; on the slightest friction it disturbs the electricity of the skin, and thus becomes a source of irritation. Sometimes, it is true, this irritation is advantageous, as causing a determination of blood to the surface; but when this action is not required, it is disagreeable, and quite equal, in a sensitive constitution, to producing an eruption on the skin. I have seen eruptions occasioned in this manner, and, when they have not occurred, so much itching and irritation as to call for the abandonment of the garment.” (Eras. Wilson.)

Silk is characterised by its fibres appearing perfectly smooth and cylindrical, without depressions, even under a magnifying power of 160. Its fibres (even when dyed) acquire a permanent straw-yellow colour when steeped in nitric acid of the sp. gr. 1·20 to 1·30. The fibres of white or light-coloured silk are similarly stained by a solution of picric acid. A thread of silk, when inflamed, shrivels and burns with difficulty, evolves a peculiar odour, and leaves a bulky charcoal. By these properties silk is distinguished from cotton and linen.

Cotton, wool, and silk may be easily distinguished from each other by means of the microscope.

The cotton fibre will be seen to consist of only one cell; wool (as well as hair and alpaca) is made up of numerous cells in juxtaposition; whilst silk fibre is similar to the secreted matter of spiders and caterpillars.

The silk fibre (fig. 1) is smooth, cylindrical, devoid of structure, not hollow inside, and equally broad. The surface is glossy, and only seldom are any irregularities seen on it. If it is desired to detect in a woven fabric the genuineness of the silk, it is best to cut a sample to pieces, place it under water under the object-glass of a microscope, magnifying 120 to 200 times, covering it with a thin piece of glass. The round, glazed, equally proportioned silk fibre (fig. 1), is easily distinguished from the unequalled and scaled wool fibre (W in fig. 2), and from the flat, band-like, and spiral cotton fibre (B, fig. 3). Under the microscope also the mixture of inferior with superior fibres of silk can be easily detected.

Black silk, the weight of which has been augmented by extensive sophistication, is not uncommon in English, French, and German markets. It is known as ‘weighted’ or ‘shotted’ silk, and very frequently contains no more—and frequently less—than one third of its weight of silk, the remaining two thirds consisting, according to Persoz, of a combination of iron salts, with some astringent substance, salts of tin, and cyanides. It is easily distinguishable from genuine silk by its want of elasticity and tenacity, and its much greater combustibility. Persoz found a specimen of this adulterated silk to yield, upon incineration, more than 8 per cent. of ferric oxide.

The cleaning and renovation of articles of wearing apparel made of silk are matters requiring some care. No silk goods look well after being washed, however carefully it may be done; and this method should, therefore, never be resorted to but from absolute necessity. It is recommended to sponge faded silks with warm water and curd soap, then to rub them with a dry cloth on a flat board, and afterwards to iron them on the wrong side with an ordinary smoothing iron. Sponging with spirit, benzol, or pure oil of turpentine, also greatly improves old silk, and is often preferable to any other method. The odour of the benzol passes off very quickly, that of the turpentine after exposure for a few days. When the ironing is done on the right side thin paper should be spread over the surface to prevent ‘glazing.’ See Dyeing, Gilding, &c.

Silk Material, a New. The ‘Textile Manufacturer’ contains the following:—The utilisation of new substances as raw material for manufactures is a distinguishing feature of the scientific investigations of the nineteenth century. One of the most recent suggestions is the result of the researches of Herr Tycho Tulburg, an eminent German naturalist, on the products of the mussel. It will be remembered it was from one of the mussel species the famous purple dye was in past ages obtained, and this colour gained an imperishable renown from its being adopted by the Roman emperors, and the imperial purple became the symbol of sovereignty. In these latter days animal products have been displaced by aniline dyes, and there is no likelihood of their regaining their former celebrity. The researches of Tulburg have not, however, been in the direction of dyes, but in the adaptation of animal products other than the silkworm for silk yarns. The mussel (Mytilus edulis) fastens itself to the rocks by strong threads, called by naturalists byssus, and it is this substance which it is proposed to utilise for the manufacture of silk. The material is of a silky texture and very tough, and the experiments that have been made prove that it is well adapted to be made into yarn. Already the Pinna, one of the mussel tribe, has been already manufactured into fabrics, although it is not of general use, nor at present of much commercial value, and the same obstacles to the use of the byssus of the common mussel are apparent. Notwithstanding the abundant supply of this popular shell fish, it is difficult to see how a sufficient quantity of byssus can be collected to enable manufacturers to purchase the raw material at rates low enough for a marketable remuneration on the manufactured article. But the records of industrial progress testify to greater difficulties than these having been successfully overcome; and should the commercial value of the new material be satisfactorily demonstrated, there is no doubt some agency will be developed whereby the requisite supply may be obtained.

At present it is sufficient to notice the discovery that has been made, and to welcome another instance of the results of scientific labour being for the advantage of manufacturers.

SILK′WORM, Diseases of. Silkworms are liable to a disease known as pébrine, which Pasteur has shown to be due to the presence, on the body, the egg, and in the blood of the insect, of peculiar parasitic corpuscles.

Pasteur states that the black specks which constitute these bodies are very easily distinguishable in the moth of the silkworm, but that in the earlier stages of its development, such as in the egg and worm condition, the detection of them becomes difficult, if not impossible. Pasteur further adds that sound moths produce sound eggs, and unsound moths the reverse, and that although the unsound eggs show no sign of disease, they never give rise to healthy worms.

Pasteur advises the silk cultivator, therefore, to ensure breeding from healthy moths at starting, and to abandon the old and useless precaution of hatching apparently healthy eggs.

The loss resulting from the silkworm disease in Italy may be seen from the following tables, which are calculated for bales of 102 lbs. weight:—

Average production prior to disease, 81,600.

1863 Bales, 50,600 Deficit, 38 per cent.

1864 ” 38,000 ” 53 ”

1865 ” 38,700 ” 52 ”

1866 ” 39,600 ” 51 ”

1867 ” 44,000 ” 46 ”

1868 ” 41,000 ” 49 ”

1869 ” 47,300 ” 42 ”

1870 ” 69,900 ” 14 ”

1871 ” 76,300 ” 6 ”

1872 ” 68,000 ” 16 ”

The value of the cocoons grown in the whole world in 1870 was said to be as follows:—France, £4,334,000; Italy, £11,260,000; Spain and other European countries, £984,000; giving a total for Europe of £16,588,000. China, £17,000,000; India, £4,800,000; Japan, £3,200,000; Persia, £920,000; other Asiatic states, £2,192,000; giving a total for Asia of £28,112,000. Africa, £68,000. America, £20,000. Making a general total of £44,788,000.

Silkworm Gut. See Gut.

SIL′LABUB. Prep. Grate off the yellow peel of a lemon with lump sugar, and dissolve the sugar in ⁄4 pint of wine; add the juice of ⁄3 a lemon, and a ⁄4 pint of cream; beat the whole together until of a proper thickness, and then put it into glasses.

Obs. ⁄4 to 1 pint of new milk is often substituted for the cream, and strong cider or perry for the wine. Grated nutmeg is often added. When ‘whipped’ to a froth it is called ‘WHIPPED SILLABUB,’ See Cream (Whipped).

SILVER. Ag. Syn. Argentum, L. This metal, like gold, appears to have been as much valued in the remotest ages of antiquity of which we have any record, as at the present time. It is found in nature, both in the metallic state and mineralised, in the state of alloy, and combined with sulphur, chlorine, and other metallic sulphurets. In Great Britain it is found in combination chiefly with lead. It is extracted from its ores principally by the process of amalgamation, founded on its easy solubility in mercury, and by subsequent cupellation. It is only prepared on the large scale.

Chemically pure silver may be obtained by the methods noticed subsequently.

Prop. Pure silver has a very white colour, a high degree of lustre, is exceedingly malleable and ductile, and is the best conductor of heat and electricity known. Its hardness is between that of copper and gold; its sp. gr. is 10·475 to 10·500; it melts at about 1873° Fahr.; or bright redness (Daniell); is freely soluble in nitric acid, and dissolves in sulphuric acid by the aid of heat; it refuses to oxidise alone at any temperature, but, when strongly heated in open vessels, it absorbs many times its bulk of oxygen, which is again disengaged at the moment of solidification; its surface is rapidly tarnished by sulphuretted hydrogen and by the fumes of sulphur.

Pur. “Entirely soluble in diluted nitric acid. This solution, treated with an excess of muriate of soda, gives a white precipitate entirely soluble in ammonia water, and a fluid which is not affected by sulphuretted hydrogen.” (Ph. E.)

Tests. 1. The compounds of silver, mixed with carbonate of soda, and exposed on a charcoal support to the inner flame of the blowpipe, afford white, brilliant, and ductile metallic globules, without any incrustation of the charcoal.—2. The salts of silver are non-volatile and colourless, but most of them acquire more or less a black tint by exposure to full daylight.

The soluble salts of silver give—1. A white curdy precipitate (chloride of silver) with hydrochloric acid and the soluble metallic chlorides, which is soluble in ammonia and insoluble in nitric acid, and blackened by exposure to light;—2. White precipitates with solutions of the alkaline carbonates, oxalates, and ferrocyanides;—3. Yellow precipitates with the alkaline arsenites and phosphates;—4. With the arseniates, red precipitates;—5. With the fixed alkalies, brown precipitates;—6. With sulphuretted hydrogen and hydrosulphuret of ammonia, a black powder, which is insoluble in dilute acids, alkalies, alkaline sulphurets, and cyanide of potassium, but readily soluble, with separation of sulphur, in boiling nitric acid; and—7. With phosphorus, and with metallic copper or zinc, pure silver.

Assay. 1. The method of assaying silver by cupellation has been explained under Assay and Cupellation; and that method is alone applicable when the alloy contains a very small quantity of silver, as a few ounces only per ton. When the reverse is the case, as with the silver of commerce, the following is a much more accurate method:—

2. Humid assay of silver.—a. Dissolve 10 gr. of the silver for assay in 100 gr. of nitric acid, sp. gr. 1·28, by the aid of heat, the solution being made in a tall stoppered glass tube, furnished with a foot; then place it in a very delicate balance, bring it into an exact state of equilibrium, and add the test solution (see below), gradually and cautiously, until the whole of the silver be thrown down, the number of grains now required to restore the equilibrium of the balance or scales gives the exact quantity of pure silver in 1000 parts of the sample.—Obs. To ensure accuracy, after each addition the stopper should be placed in the tube, and the latter violently agitated for a short time, when the liquor will rapidly clear and enable us to see when the operation is concluded. We must then, as a check, add a small quantity of a solution of nitrate of silver to the liquor in the tube, after having first carefully taken the weight. If too much of the test liquor has been added, this will produce a fresh precipitate, and the assay cannot then be depended on.—Instead of weighing the quantity of test liquor used, a tube graduated into 100 parts, and holding 1000 gr., may be employed, every division of which, required to throw down the silver, will represent the ⁄10th of a grain. See Alkalimetry and Acidimetry.

b. The precipitate of chloride of silver may be collected in a paper filter, and be dried, washed, fused, and weighed. The previous weight of the paper, deducted from the gross weight of the filter and its contents, gives the quantity of chloride of silver present, which multiplied by 0·75278, gives the weight of the pure silver in the sample.

Test liquor. Dissolve 54·27 (54⁄4) gr. of pure sea salt in 9945·73 gr. (or 22 oz. and 320⁄4 gr. avoirdupois) of distilled water; filter, and keep the liquor in a stoppered bottle for use. Pure sea salt is obtained by boiling together, for a few minutes, in a glass vessel, a solution of common salt with a little pure bicarbonate of soda; then adding to the filtered liquor sufficient hydrochloric acid to render it neutral to litmus and turmeric paper, and, lastly, evaporating and crystallising.

Obs. The presence of mercury, lead, or sulphuret of silver, interferes with the accuracy of the above assay. When mercury is present, the precipitate blackens less readily by exposure to light; and when it contains ⁄1000 or ⁄1000 of chloride of mercury, it remains of a dead white; with ⁄1000 it is not sensibly discoloured by the diffused light of a room, with ⁄1000 only slightly darkened, with ⁄1000 more so, but with pure chloride of silver, the effect is very rapid and intense. When this metal is present, which is, however, seldom the case, the assay sample must be placed in a small crucible, and exposed to a full red heat, before solution in the acid. Another method, proposed by M. Levol, and modified by M. Gay-Lussac, is to add to the nitric solution of the silver sufficient acetate of ammonia or crystallised acetate of soda to saturate all the nitric acid existing in the liquor, either in the free state or combined with the silver. When the alloy contains lead, shown by the precipitated chloride being partly soluble in water, it may either be laminated and subjected to the action of acetic acid before solution in the nitric acid; or, the test solution of chloride of soda should be replaced by one of chloride of lead; (139·355 gr. of the latter are equiv. to 58·732 gr. of the former). The presence of sulphuret of silver is detected whilst dissolving the sample in nitric acid, by the black flakes which may be observed floating about in the liquor in an insoluble state. These flakes may be dissolved by fuming nitric acid, or by adding pure concentrated sulphuric acid to the solution, which should be then heated for about a ⁄4 hour in a steam-bath. When thus treated, the precipitate produced by the test liquor represents the whole of the silver contained in the alloy.

Dr Gräger gives the following process of the preparation of pure metallic silver:—He dissolved the alloy of silver in nitric acid, taking care to use as small a quantity of the acid as possible. The solution is then transferred to a large-sized porcelain basin, and gradually neutralised with previously lixiviated chalk free from chlorine. The neutralised liquid is next boiled, and chalk again added to it, while boiling, until the fluid has become colourless. (In order to test more accurately, a drop of the liquid is poured on a piece of white filtering-paper, and next to that drop is placed one of a solution of ferrocyanide of potassium; as long as the well-known red colouration, copper reaction, hereby ensues, chalk is added.) The fluid is next filtered to separate the carbonate of copper, and the filtrate (a solution of nitrate of silver, and nitrate of lime) is again boiled, and either further treated with carbonate of lime, or better still, with carbonate of soda. The bright yellow-coloured precipitate thereby ensuing, a mixture of carbonate of silver, and carbonate of lime, is washed, dried, and ignited, leaving a greyish-white mass of metallic silver, mixed with carbonate of lime. This mixture is treated with dilute hydrochloric acid, washed with distilled water, and then fused along with borax, yielding pure silver. The bright green coloured carbonate of copper can be used as a pigment for painting purposes.

Krüger says:—In frequently experimenting with silver salts, a mixture of solution of precipitates is obtained, in which silver exists in all kinds of combination. When such mixtures are shaken up with an ethereal solution of phosphorus, the solution and the precipitate soon separate, the former being more or less yellow, the latter intensely black. If light-coloured particles are perceived in the precipitate, the quantity of phosphorus solution employed is not sufficient, and more must be added till the precipitate is uniformly black. The precipitate is next filtered, washed, and dried, or placed while still damp, in a porcelain dish and boiled with potash solution. Pure metallic silver is thus obtained. If a solid fused mass is required, pure potassium hydrate is fused in a crucible, and to this the dried precipitate is added in small portions.

Uses, &c. Metallic silver, unless in a state of very minute division, has no action on the human body. A plate of silver is ordered, in the Ph. L., as a test of the presence of nitric acid in the acetic and phosphoric acids; and metallic silver (preferably granulated) is employed by the other colleges in the preparation of the nitrate. Its numerous applications in the arts are well known. The standard silver of England contains 111 parts of silver and 9 parts of copper.

Concluding Remarks. The researches of Tillet, D’Arcet, and Gay-Lussac have clearly shown that the percentage of silver in an alloy, as indicated by cupellation, is always below its real richness in that metal, owing to loss in the process; and, that the cupelled button always retains a trace of lead and copper, the precise quantity of which is variable. The following table exhibits the additions to be made on this score, when the quantity assayed (assay pound) is 20 gr.:—

Weight after
cupellation. Actual richness
in pure silver. Percentage of richness
in pure silver.

19·979 20 100

18·95 19 95

17·92 18 90

16·917 17 85

15·914 16 80

14·91 15 75

13·905 14 70

12·905 13 65

11·906 12 60

10·906 11 55

9·906 10 50

7·921 8 40

5·948 6 30

3·949 4 20

1·982 2 10

In assaying lead ores very poor in silver the best quantity to be taken for cupellation is 500 gr.; and from that quantity 0·0148 of silver, including compensation for loss, represents one ounce of silver to the ton. A cupel may absorb its own weight of lead. If the quantity of lead to be absorbed is more considerable, another cupel may be turned topsy-turvy, and the cupel in which the assay is to be made may be placed upon it. See Assay, and M. Gay-Lussac’s elaborate memoir on the ‘Humid Assay of Silver,’

For the recovery or reduction of silver from the chloride and its other compounds, several methods are employed:—

a. The washed chloride is placed in a zinc or iron cup, along with a little water strongly acidulated with sulphuric acid; or in a glass or porcelain cup along with a zinc plate; the whole may then be left to itself for some hours; or, to hasten the reduction, gently heated, or even boiled; the precipitated silver is washed with pure water, and dried.

b. (Hornung.) Digest the chloride with some ammonia and pure copper filings, for 24 hours, then wash and dry the powder.

c. (M. Levol.) The washed chloride is mixed with an equal weight of sugar, and the mixture is digested in an excess of a moderately strong solution of caustic potassa, with occasional agitation for 24 hours; or the whole is boiled for some time; the reduced silver is washed with distilled water.

d. (Mohr.) The dry chloride is mixed with 1-3rd of its weight of powdered black resin, and moderately heated in a crucible until the flame ceases to have a greenish-blue colour; the heat is then suddenly increased so as to melt the metal into a button or ingot.

e. (M. Gay-Lussac.) If the chloride, dry it, and throw it, in successive portions, into twice its weight of carbonate of potassa fused in a red-hot Hessian crucible; effervescence ensues, and the pure silver subsides to the bottom.—If a “soluble salt,” as the nitrate, acidulate the solution, and precipitate it by means of a polished plate of copper; the silver is then obtained in the form of powder. The products of the above processes, when the latter are carefully conducted, are chemically pure silver.

Silver, Acetate of. Syn. Argenti acetas, L. Prep. By adding a solution of acetate of potassa to a like solution of nitrate of silver, washing the precipitate with cold water, redissolving it in a little hot water, and setting the solution aside to crystallise. Small colourless needles.

Silver, Ammoniuret of. See Fulminating silver (Berthollet’s, Nos. 1 and 2, page 768).

Silver, Ammonio-chloride of. Syn. Argentochloride of ammonia; Argenti ammonio-chloridum, L. Prep. Add, gradually, chloride of silver (recently precipitated and well washed) to concentrated liquor of ammonia, as long as it is dissolved on agitation, applying a gentle heat towards the end; then heat the solution to the boiling-point, concentrate a little, and allow it to cool very slowly; collect the crystals which form, dry them by pressure (with care) between folds of bibulous paper, and at once preserve them from the light and air.—Dose, ⁄16 to ⁄8 gr.

Silver, Ben′zoate of. AgC7H5O2. Thin transparent plates, which are blackened by exposure to the light. See Benzoate.

Silver, Bro′mide of. AgBr. Resembles the chloride.

Silver, Car′bonate of. Ag2CO3. Syn. Argenti carbonas, L. A white insoluble powder, obtained by precipitating a cold solution of nitrate of silver with another of carbonate of sodium. It is decomposed by heat.

Silver, Chlo′′ride of. AgCl. Syn. Argentic chloride. Prep. Precipitate a solution of nitrate of silver by dilute hydrochloric acid or a solution of common salt; wash the precipitate, and dry it in the shade.—Dose, ⁄4 to 3 gr., thrice daily; in epilepsy, chronic dysentery, cholera, diarrhœa, &c. Dr Perry regards it as preferable to the nitrate. When fused, chloride of silver forms horn silver, the ‘luna cornea’ of the older writers.

Silver, Cy′anide of. AgCN. Syn. Argentic cyanide, Hydrocyanate of silver. Prep. Add dilute hydrocyanic acid to a solution of nitrate of silver, as long as a precipitate falls; wash this with distilled water, and dry it.

Prop., &c. Cyanide of silver is a white powder, soluble in ammonia, and decomposed by contact with vegetable substances; light turns it violet-coloured.—Dose, ⁄16 to ⁄8 gr.; in syphilis, &c. It has been proposed as a source of hydrocyanic acid. (Everitt.)

Silver Hyposul′phite of. Ag2S2O3. Syn. Argenti hyposulphis, L. A white substance, insoluble in water, and very prone to decomposition. It is very soluble in the alkaline hyposulphites, forming compounds possessing an intensely sweet taste. See Hyposulphurous Acid.

Silver, I′odide of. AgI. Syn. Argentic iodide; Argenti iodidum, L. Prep. Precipitate a solution of nitrate of silver with another of iodide of potassium; wash the precipitate with distilled water, and dry it in the shade. Pale greenish-yellow; insoluble in water and in liquor of ammonia; soluble in a solution of hyposulphite of soda. Used in some of the French hospitals in the stomach affections of scrofulous subjects: also in epilepsy.—Dose, ⁄12 to 1 gr.

Silver, Ni′trate of. AgNO3. Syn. Argenti nitras, L. This article is found in commerce under two forms:—

1. Crystallised. Prep. By dissolving grain silver in nitric acid diluted with about twice its weight of water, evaporating the solution until it is strong enough to crystallise on cooling, and then allowing it to cool very slowly. Colourless; transparent, anhydrous rhombic prisms or tables; soluble in an equal weight of cold and in half their weight of boiling water; soluble in alcohol; fuse when heated, and at a higher temperature suffer decomposition; blackened by light, and by contact with organic substances. Its solution in distilled water is not sensibly darkened by light, in the absence of organic matter. Used for solutions, and in photography.

2. Fused (Lunar caustic; Argenti nitras—B. P., Ph. L. & E., A. n. fusum—Ph. D.). Prep. (Ph. D.) Refined silver, 3 oz.; pure nitric acid, 4 fl. oz.; distilled water, 5 fl. oz.; mix in a glass flask, and apply in a gentle heat until the metal is dissolved; transfer the solution to a porcelain capsule (or a large porcelain crucible), decanting it off a heavy black powder which appears at the bottom of the flask, and, having evaporated it to dryness, raise the heat (in a dark room) until the mass liquefies; then pour it into a brass mould (iron moulds—Ph. E. & Ph. L. 1836), furnished with cylindrical cavities of the size of a goose-quill, and which then admits of being opened by a hinge; preserve the concreted salt in well-stopped bottles, impervious to the light. The formulæ of the Ph. E. & Ph. L. 1836 are similar.

Obs. In preparing this salt care should be had that the silver is free from copper. Pure nitrate of silver may, however, be prepared from silver containing copper, by evaporating the nitric solution to dryness, and cautiously heating the mixed nitrates to fusion. A small portion of the melted mass is examined from time to time, until a little dissolved in water, and treated with ammonia in excess, ceases to strike a blue colour. When this point is arrived at, the fused nitrate is allowed to cool, when it is redissolved in water, filtered or decanted from the insoluble black oxide of copper, and evaporated in the usual way.

The heat employed in preparing the fused nitrate should not exceed 420° Fahr., and the fusion should be effected completely, but with moderate expedition, to prevent loss of nitric acid. Formerly, a mass of well-tempered white clay, perforated by means of a well-greased goose-quill, was used instead of metal moulds. In the Ph. E. & Ph. L. 1836 the moulds are ordered to be greased; when this is done, the sticks of caustic should be wiped clean before rolling them in paper. The moulds should be gently heated before pouring the fused nitrate into them. Mr Benzoin, the celebrated Danish pharmaceutist, recommends mould formed of the massive white Bohemian talc or of English slate.

Pur., &c. Pure nitrate of silver, whether crystallised or fused, is entirely soluble in water, yielding a colourless solution, from which metallic silver is precipitated by a piece of bright copper; both are originally white, but are darkened by exposure to light and contact with organic matter.

Uses, &c. Nitrate of silver is a powerful tonic, antispasmodic, astringent and escharotic.—Dose, ⁄8 to 1 gr., gradually increased, twice or thrice a day, made into a pill with crum of bread; in cholera, epilepsy, &c., preceded by purgatives. It has been highly extolled by Mr Ross as a remedy in cholera. Its continued use permanently colours the skin. It is also extensively employed externally as a caustic. It is powerfully poisonous. A solution of common salt, emetics, and demulcents, constitute the treatment in such cases. Nitrate of silver is much employed in the manufacture of ‘indelible ink’ for linen, and hair dyes.

Silver, Di′oxide of. Ag2O2. Syn. Argenti suboxydum, L. Prep. From dry citrate of silver heated to 212° Fahr., in a stream of hydrogen gas, until it turns dark brown, when it is dissolved in water; the solution is next treated with potassa, and the precipitate is carefully washed and dried. A black powder, easily decomposed, and soluble in ammonia.

Silver, Oxide of. Ag2O. Syn. Protoxide of silver; ARGENTI OXYDUM, A. PROTOXYDUM, L. Prep. 1. (Lane.) Nitrate of silver, 2 parts; hydrate of potassa, 1 part; dissolve each separately in distilled water, mix the solutions, and, after frequent agitation during an hour, collect and wash the precipitate, and dry it by a gentle heat in the shade. A pale brown powder.

2. Recently precipitated chloride of silver is boiled in a solution of hydrate of potassium of the sp. gr. 1·25, with frequent stirring and trituration, until, on testing a little of it, it is found to be entirely soluble in dilute nitric acid, when it is washed and dried, as before. A black and very dense powder. Chemically pure.

3. Nitrate of silver, ⁄2 oz.; water, 4 fl. oz., dissolve, and pour the solution into a bottle containing lime water, 2 quarts, or q. s.; agitate the mixture well, collect and wash the sediment, and dry it at a heat not exceeding 212° Fahr. A dark olive-brown powder. Pure.

Prop., &c. Very soluble in solutions of ammonia and of the alkaline hyposulphites; slightly soluble in water; reaction alkaline; decomposed by light.—Dose, ⁄2 to 2 gr.; in epilepsy, gastralgic irritations, &c. It is much used in France, and has been highly extolled in menorrhagia. By some, however, it is not considered superior to the nitrate.

Silver Pencils, Nitrate of. According to A. Huber, very thin pencils of nitrate of silver, such as are sometimes required for intra-uterine applications may be prepared in the following manner:—Silver nitrate is fused in a capsule, and the liquid drawn up by slow and cautious suction into a glass tube, the calibre of which is a trifle larger than the required diameter of the pencil. Especial care is to be taken that no cavities filled with air-bubbles are produced in the contents of the tube. When entirely cold the tube is warmed by turning over a spirit-lamp until the outer surface of the stick has become soft, when it may be easily pushed out by means of a knitting needle. With a little practice very handsome pencils of considerable length may be obtained in this manner.

Silver, Perox′ide of. Syn. Argenti peroxydum, L. A black crystalline substance which forms on the positive electrode of a voltaic arrangement employed to decompose solution of nitrate of silver.

Silver, Sul′phate of. Ag2SO4. Syn. Argenti-sulphas, L. Prep. By boiling silver in sulphuric acid; or, by precipitating a solution of the nitrate by another of sulphate of sodium. It dissolves in 80 parts of hot water, and falls in small colourless needles as the solution cools.

Silver, Sul′phide of. Ag2S. Syn. Sulphuret of silver; Argenti sulphuretum, L. Prepared by passing sulphuretted hydrogen through a solution of nitrate of silver; or, by melting its constituents together. It possesses a greyish-black colour, and is a strong sulphur-base.

Silver, Ox′idised. The high appreciation in which ornamental articles in oxidised silver are now held, renders a notice of the process followed interesting. There are two distinct shades in use, one produced by chlorine, which has a brownish tint, and the other by sulphur, which has a bluish-black tint. To produce the former, it is only necessary to wash the article with a solution of sal ammoniac. A much more beautiful tint may, however, be obtained by employing a solution composed of equal parts of sulphate of copper and sal ammoniac dissolved in vinegar. A fine black tint may be produced by a slightly warm solution of sulphide of potassium or of sodium. (‘Chem. Techn.’)

SILVER DUST. Syn. Silver powder; Argenti crocus, A. pulvis, L. Prep. 1. Pure pulverulent silver, obtained by any of the methods explained on the previous page. Used to coat pills, by japanners, &c.

2. Heat oxide of silver to dull redness in a porcelain crucible, cool, triturate the powder in an agate mortar, and pass it through a fine sieve. Used at the hospital of Montpellier.

SILVER SHELLS. These are prepared and used like gold shells.

SIL′VERING. The art of covering the surfaces of bodies with a thin coating of silver. Leather, paper, wood, &c., are silvered by covering them with silver leaf, by a similar process to that employed for gilding them.

Silvering of Glass. Two distinct methods are adopted for this purpose—one of which consists in employing a layer of tin-foil and mercury, falsely called ‘silvering,’ the other in using a coating of real silver precipitated from a solution of that metal.

1. Plane surfaces, as those of mirrors, &c., are commonly silvered as follows:—A sheet of tin-foil corresponding to the size of the plate of glass is evenly spread on a perfectly smooth and solid marble table, and every wrinkle on its surface is carefully rubbed down with a brush; a portion of mercury is then poured on, and rubbed over the foil with a clean piece of very soft woollen stuff, or a hare’s foot, after which two rules are applied to the edges, and mercury poured on to the depth of a crown-piece, when any oxide on the surface is carefully removed, and the sheet of glass, made perfectly clean and dry, is slid along over the surface of the liquid metal, so that no air, dirt, or oxide can possibly either remain or get between them. When the glass has arrived at its proper position, gentle pressure is applied, and the table sloped a little to carry off the waste mercury, after which it is covered with flannel and loaded with heavy weights; in 24 hours it is removed to a wooden table and further slanted, and this position is progressively increased during a month, until it becomes perpendicular.

For silvering convex or concave surfaces a mould of plaster of Paris is employed, so that the amalgamated foil may be accurately fitted to the surface.

Globes and other hollow vessels are commonly silvered by the application of one of the silvering amalgams noticed at page 117.

2. In the HUMID WAY.—a. (Drayton.) A mixture is first made of nitrate of silver (in coarse powder), 1 oz., ammonia, ⁄2 oz., and water, 2 oz., which, after standing for 24 hours, is filtered (the deposit upon the filter, which is silver, being preserved), and an addition is made thereto of spirit (by preference, rectified spirit at 60% o. p.), or naphtha, 3 oz.; from 20 to 30 drops of oil of cassia are then added; and, after remaining for about 6 hours longer, the solution is ready for use. The glass to be silvered (first well cleaned and polished) is placed in a horizontal position, and a wall of putty, or other suitable material, formed around it; the above solution is then poured over it to the depth of from ⁄8 to ⁄4 inch; from 6 to 12 drops of a mixture of oil of cloves and spirit of wine (in the proportion of 1 part, by measure, of oil of cloves, to 3 of spirit of wine) are next dropped into it, at different places; or the diluted oil of cloves may be mixed with the solution before it is poured upon the glass, a larger quantity, in both cases, increasing the rate of the deposit. When the glass is sufficiently silvered, the solution is poured off; and as soon as the silver on the glass is perfectly dry, it is varnished with a composition formed by melting together equal quantities of beeswax and tallow. The solution, after being poured off, is allowed to stand for 3 or 4 days, in a close vessel; as it still contains silver, and may be again employed after filtration, and the addition of a sufficient quantity of fresh ingredients to supply the place of those which have been used. 18 gr. of nitrate of silver are sufficient for one square foot of glass. Hollow vessels may he silvered by pouring the solution into them. By the addition of a small quantity of oil of caraway, oil of cloves, or oil of thyme, the colour of the silver may be varied. (‘Patent Journ.’)

b. (Thomson & Mellish.) Nitrate of silver, 2 oz.; water and rectified spirit, of each 3 fl. oz.; dissolve, add of spirit of hartshorn or liquor of ammonia, 1 fl. oz., mix, and after a short time filter the solution; to each ounce of this add of grape sugar, ⁄4 oz., previously dissolved in a mixture of rectified spirit and water, of each ⁄2 pint; after 3 or 4 hours’ repose it is fit for use. This solution is applied to the glass, heated to about 160° Fahr., in a similar manner to the last. Patented.

c. The best plan of silvering plain or slightly curved surfaces is, however, the method employed for coating the specula of the silvered-glass Newtonian telescopes. This method is very easy, and has the advantages of giving a brilliant and durable surface on both sides, and the film is sufficiently firm to admit of being polished with rouge and fine wash-leather.

One half ounce of pure nitrate of silver is dissolved in 4 oz. of distilled water, and divided into two equal portions. One is treated with dilute ammonia until the brownish precipitate is entirely redissolved; and to this clear solution, ⁄2 oz. of pure hydrate of potassium dissolved in 8 oz. of water added; and the brown precipitate, and grey sediment that remains after the brown precipitate disappears, dissolved by the cautious addition of ammonia, stirring well all the time. The remaining nitrate of silver solution is now added, stirring well until it gives a greyish precipitate that does not disappear after well stirring. The bulk of the solution is next made up to 100 oz., and allowed to settle, when the clear solution is poured off for use.

The reducing solution is prepared by dissolving ⁄2 oz. of pure milk sugar in 10 oz. of hot water, and adding 10 minims of pure alcohol.

This quantity of silvering solution will coat over two square feet of glass surface with a brilliant film of pure silver. The glass must be perfectly clean, and is to be suspended face downwards on the surface of the solution and allowed to stand one hour; the temperature of the solution being best about 80° Fahr.

d. (R. Siemens.) As a reducing agent, acetic aldehyde is used in the form of aldehyde ammonia, prepared by passing dry ammoniacal gas into aldehyde. Four grams of silver nitrate and 2⁄2 grams of aldehyde ammonia are separately dissolved in a litre of distilled water, and the solutions mixed and filtered. The article to be silvered, after washing out with potassium carbonate, and then with spirits of wine and distilled water, to remove every trace of grease, is filled with this solution (as far as it is desired to silver), and then hung up in the water bath.

It is now gradually heated, and as soon as the temperature reaches 50° C. the separation of the silver mirror begins, and soon spreads over the whole inner glass surface. Its formation is soon finished, usually between 55° or 60°. When the beauty of the silver surface reaches a maximum it is time to withdraw the article from the water bath, and pour off the contents, or the brilliancy of the mirror will be impaired. The article is finally rinsed in distilled water.

e. (Martin.) M. Martin makes use of four liquids, viz., first, a 10 per cent. solution of nitrate of silver; second, liquor ammoniæ, sp. gr. ·970; third, a 4 per cent. solution of caustic soda; and fourth, a 12⁄2 per cent, solution of white sugar, to which he adds 2⁄2 per cent. of nitric acid, and after twenty minutes’ boiling he adds to it 25 parts of alcohol and water, to make up the bulk to 250. The silvering solution is made by mixing together 12 parts of solution No. 1, 8 parts of No. 2, 20 parts of No. 3, and 60 parts of distilled water, and finally, in twenty-four hours, 10 parts of No. 4. The object to be silvered is then immersed, when it will be covered with a film of reduced silver, which in ten minutes’ time will be sufficiently thick for use. After having been washed with distilled water and dried the surface may be polished with chamois leather and rouge.

Silvering of Metals. 1. (Leaf silvering.) This is performed with leaf silvering in the way described under Gilding for the gilding of polished metals.

3. (Cold silvering.) Mix chloride of silver, 1 part, with pearlash, 3 parts, common salt, 1⁄2 part, and whiting, 1 part; and well rub the mixture on the surface of the brass or copper (previously well cleaned), by means of a piece of soft leather, or a cork moistened with water and dipped into the powder. When properly silvered the metal should be well washed in hot water slightly alkalised, and then wiped dry.

3. (Electeo-silvering.) This is described under Electrotype.

Silver, A New Imitation of. A patent for an alloy has been taken out by M. Lemarquand, which is said to bear a close resemblance to silver in appearance, and to be unaffected by atmospheric influences. It has the following composition:—

Pure copper 750 parts.

Nickel 140 ”

Black oxide of cobalt 20 ”

Tin, in sticks 18 ”

Zinc 72 ”

SIMAROU′BA. Syn. Simaruba (Ph. E. & D.), L. The root-bark of Simaruba amara or officinalis, the mountain damson. Tonic, bitter, and astringent.—Dose, 20 to 30 gr.; in intermittents, obstinate diarrhœa, dysentery, and dyspepsia.

SIN′AMINE. C4H6N2. A basic substance formed, along with sulphide of lead, when thiosinamine is treated with oxide of lead. It is very bitter tasted, has a powerful alkaline reaction, and, when slowly obtained from its concentrated aqueous solution, forms brilliant colourless crystals.

SIN′APISM. Syn. Sinapismus, L. A mustard poultice.

SIN′APOLINE. C7H12N2O. A basic substance, formed, along with carbonic acid, when the volatile oil of mustard, or sulphocyanide of allyl, is treated with oxide of lead. It is soluble in water and alcohol, has an alkaline reaction, and crystallises in colourless plates.

SINKS. “In no case,” says Mr Eassie, “should the waste pipe of sink, laboratory, or bath lead direct into the drains; yet how frequently is this the case, and a special card sent out to disease and death.

“It must also be remembered it is every whit as dangerous if these waste conduits lead into the soil pipe of a closet. Waste pipes from the above-named places should be led down to within 12 or 18 inches from the ground, and should deliver on to the grating of a gully or yard trap.”

This subject has been already treated in the article on “Sanitation, Domestic,” wherein we have embodied the practical suggestions of Mr Collins, another sanitary house reformer, as well as in our article on “Drainage,” in which will be found details for carrying out the system recommended by Messrs Eassie and Symonds, and thus preventing the admission into our dwelling-houses of the poisonous sewer gas.

The matter has so important a bearing upon health, that we shall make no apology for having thus reiterated and emphasised it by quoting Mr Eassie’s words of warning. See Traps.

SIT′FASTS. These hard tumours, possessing but little sensibility, are situated in those superficial parts of the horse’s body which have been exposed to the unequal pressure of the collar, the saddle, or the harness. The tumour should be removed by the veterinary surgeon, if the previous application of either blisters, biniodide of mercury ointment, or a seton have been tried and failed to disperse it. The precursor of the sitfast is always a swelling filled with serum and lymph, caused, as before stated, by badly-fitting harness. Hence the soundest treatment is to prevent its development into the hard form, by proper means, directly it shows itself, the best remedies being the application of salt and water or Goulard water, and correcting the defects of the harness.

SIZE. Obtained, like glue, from the skins of animals, but is evaporated less, and kept in the soft state. See Gold and Gold size.

Size, Oil. This may be made by grinding yellow ochre or burnt red ochre with boiled linseed oil, and thinning it with oil of turpentine.

SKATE. The Raia batis (Linn.). Other varieties of Raia also pass under the name. It is a coarse fish, and is principally salted and dried for exportation.

SKIN (The). Syn. Cutis, Dermis, Pellis, L. Every person must be familiar with the external appearance and general properties of the skin; but there are many of our readers who may not be aware of its peculiar compound character. The skin, then, although apparently a single membrane, is composed of three distinct layers or membranes, each of which performs its special duties:—1. The exterior of these is called the cuticle, epidermis, or scarf-skin. It is an albuminous tissue, possessing no sensibility, and is found thickest on those parts of the body most exposed to friction or injury.—2. The mucous net, or rete mucosum, which is a thin layer of soft pulpy matter, which lies immediately under the cuticle, and is supposed to be the seat of the colour of the skin.—3. The derma, cutis vera, or true skin, is a highly sensitive, vascular, gelatinous texture, the third, and last in succession from the surface of the body. It is this which, when the scarf-skin and hair have been removed, is converted by the process of tanning or tawing into leather.

The skin, because of its tough, elastic, flexible nature and its underlying layer of fat, is admirably adapted for covering the various internal parts and organs, as well as for bodily movement and exertion. Besides this, it exercises, in common with the lungs, the liver, and the kidneys, the important function of a depurator, and may, with the organs above specified, be regarded as one of the main outlets for the waste products of the body; the effete and noxious matters of which, when in a healthy condition, it effects the removal, are those contained in the perspiration, and in addition carbonic acid, and, in the case of unhealthy subjects, nitrogen. The importance of the removal of these substances from the organism will be realised when it is stated that, when this excretory function of the skin has, in the course of experiments upon animals, been prevented by covering their bodies over with a coat of varnish or some other impermeable agent, the animal has quickly perished.

The perspiration is variable in amount, owing to various causes, such as temperature, the amount of exercise taken, the more or less hygroscopic condition of the surrounding atmospheres, the quantity of fluid swallowed, the season of the year, &c., with the exception of that which occurs under the armpits and upon the soles of the feet, it has generally an acid reaction, due to the presence in it of uncombined formic and lactic acids. Under ordinary conditions of life it averages daily about 2 lbs. in quantity, being, as might be expected, more abundant than the urine in summer, and less in winter. The perspiration is of very complex composition, and contains lactates, butyrates, and acetates of sodium and ammonium, sodic chloride, phosphate of calcium, and sulphates—these latter, however, occurring in but small quantities. It also contains a peculiar nitrogenous substance that very quickly decomposes, and a peculiar odorous principle. According to Anselmino the proportion of solid matter in the perspiration varies from 5 to 12·5 parts in 1000.

Various observers have arrived at different conclusions respecting the amount of carbonic acid exhaled from the skin. Professor Scharling believed it to be from a fortieth to a sixtieth the amount given off by the lungs. Recent observations seem, however, to have shown that this estimate was too high. Dr Edward Smith, operating upon himself by placing every part of his body except the head in a caoutchouc bag, and subsequently collecting the evolved carbonic acid (the experiment being performed in the summer time), found the quantity evolved to be 6 grains per hour, or about a hundredth part of that passing off from the lungs.

Aubert’s experiments led him to the conclusion that it was about half the amount given by Smith; whilst Reinhart estimated it at 34 or 35 grains a day.

These excretory processes of the skin are effected by means of very minute vessels called the sudoriparous or sweat-glands. These glands abound in almost every part of the human skin. They are of largest size under the axillæ or arm-pits, where perspiration is most profuse. They are also very abundant upon the palms of the hand. Professor Erasmus Wilson says that as many as 3528 of these sweat-glands exist in a square inch of surface on the palm of the hand; and as every tube, when straightened out, is about a quarter of an inch in length, it follows that, in a square inch of skin from the palm of the hand, there exists a length of tube equal to 882 inches, or 73⁄2 feet. These glands, as we have seen, vary in number for different parts of the human body; but if we take Professor Wilson’s average for the superficial area of a man of ordinary stature, viz., 2800 of them to the square inch, it follows “the total number of pores on such a man’s skin would be about seven millions, and the length of perspiratory tubing would then be 1,750,000 inches, or 145,833 feet, or 48,611 yards, or nearly 28 miles.”

In addition to the sudoriparous, the skin also possesses sebaceous glands which stud almost every part of its surface except the palms of the hands and the soles of the feet. The sebaceous glands secrete a semi-fluid, greasy kind of substance, the office of which is probably to aid in rendering the skin soft and supple, and to prevent the too rapid evaporation of moisture from it. The sebaceous glands are more particularly found on the scalp, the anus, and the nose, their locality in the skin of this last feature being sometimes marked by small black specs, which when squeezed yield a little white mass resembling a maggot in appearance. This is merely the solidified secretion from the sebaceous gland. A parasite known as the Acarus folliculorum infests the sebaceous glands. In the cartilaginous part of the external passage of the ear are other glands, the ceruminous, which secrete the wax that forms a protective film for the membrane of the tympanum or drum, and guards it against dust, insects, &c. See Exercise, Perspiration.

SKIN BALSAM, Glycerin—Glycerin Haut, Balsam. A mixture of 1000 parts glycerin, 120 parts orange-flower water, 1 part each oils of neroli and bitter almonds. (Hager.)

SKIN COSMET′ICS. The simplest, cheapest, and most generally employed cutaneous cosmetics are soap and water, which at once cleanse and soften the skin. Soap containing a full proportion of alkali exercises a solvent power upon the cuticle, a minute portion of which it dissolves; but when it contains a small preponderance of oily matter, as the principal part of the milder toilet soaps now do, it mechanically softens the skin and promotes its smoothness. Almond, Naples, and Castile soaps are esteemed for these properties, and milk of roses, cold cream, and almond powder (paste), are also used for a similar purpose. To produce an opposite effect, and to harden the cuticle, spirits, astringents, acids, and astringent salts, are commonly employed. The frequent use of hard water has a similar effect. The application of these articles is generally for the purpose of strengthening or preserving some particular part against the action of cold, moisture, &c.; as the lips, or mammæ, from chapping, or the hands from contracting chilblains; but in this respect oils, pommades, and other oleaginous bodies, are generally regarded as preferable.

Another class of cutaneous cosmetics are employed to remove freckles and eruptions. Among the most innocent and valuable of these is Gowland’s lotion, which has long been a popular article, and deservedly so, for it not only tends to impart a delightful softness to the skin, but is a most valuable remedy for many obstinate eruptive diseases which frequently resist the usual methods of treatment. Bitter almonds have been recommended to remove freckles (Celsus), but moistening them with a lotion made by mixing 1 fl. oz. of rectified spirit, and a teaspoonful of hydrochloric acid with 7 or 8 fl. oz. of water, is said to do this more effectually. A safe and excellent cosmetic is an infusion of horseradish in cold milk. (Withering.)

Hermann prescribes the following lotion:—Blanched almonds, 2 oz.; rose water, 8 oz.; orange-flower water, 2 oz. Make an emulsion, strain, and add sal ammoniac, 1 dr.; simple tincture of benzoin, 2 dr.

Skin paints and skin stains are employed to give an artificial bloom or delicacy to the skin. Rouge and carmine are the articles most generally used to communicate a red colour. The first is the only cosmetic that can be employed, without injury, to brighten a lady’s complexion. The other, though possessing unrivalled beauty, is apt to impart a sallowness to the skin by frequent use. Starch powder is employed to impart a white tint, and generally proves perfectly harmless. The American ladies, who are very fond of painting their necks white, use finely-powdered magnesia, another very innocent substance. Several metallic compounds, as the trisnitrate, chloride, and oxide of bismuth (pearl white, Fard’s white, &c), carbonate of lead (flake white), white precipitate, &c., are frequently used to revive faded complexions; but they are not only injurious to the skin, but act as poisons if taken up by the absorbents. Trisnitrate of bismuth (pearl white), probably the least injurious of these articles, has been known to cause spasmodic tremblings of the muscles of the face, ending in paralysis. (‘Voght. Pharm.’) The employment of liquid preparations containing sugar of lead, which are commonly sold under the name of milk of roses, cream of roses, &c., is equally injurious. Another disadvantage of these metallic preparations is, that they readily turn black when exposed to the action of sulphuretted hydrogen gas, or the vapours of sulphur, such as frequently escape into the apartment from coal fires. There are many instances recorded of a whole company being suddenly alarmed by the pearly complexion of one of its belles being thus transformed into a sickly grey or black colour.

In conclusion, it may be remarked that the best purifiers of the skin are soap and water, followed by the use of a coarse but not a stiff cloth, in opposition to the costly and smooth diapers that are commonly employed; and the best beautifiers are health, exercise, and good temper.

Skin, Goldbeat′er’s. See Goldbeater’s skin.

SKINS (of Animals). The preparation and preservation of fur skins are noticed under Peltry; the preparation and uses of the skins of the larger animals under Leather, Tanning, Tawing, &c.

SLACK. Small coal, such as is used for kilns.

SLAG. The semi-vitrified compounds, produced, on the large scale, during the reduction of metallic ores by fluxes. Those from iron and copper works are often used for building materials, mending roads, &c.

According to Egleston the following are some of the industrial applications to which the slag from blast furnaces is put.

When required for building stones the slag is run from the blast furnace into a semicircular vessel on moving wheels, and having its bottom covered three centimetres deep with sand and coke dust. By means of a bent iron instrument the slag is mixed with sand and coke dust till the escape of gases has nearly ceased and the mass is sufficiently tough. With the same tool it is next pressed into a mould furnished with a lid, which is forced down as soon as the escape of gas ceases. The red-hot stone is then placed in the cooling oven, covered with coke dust, and allowed to remain three or four days to cool completely. These stones are impervious to damp, and make good foundations. According to another method the slag, which should contain from 38 to 44 per cent. of silica, is run down a shoot into a large cavity, and then covered over with sand and ashes, and left to cool from five to ten days, when it is distributed in moulds, and there hardens. In certain parts of Belgium slag is poured upon iron plates and cooled by water, and thus a kind of glass is manufactured.

In other districts the slag is granulated as it flows from the blast furnace by means of a stream of water. The granulated slag is preferred by the puddlers to the sand for the moulds of pig iron. The slag gravel may be advantageously substituted for sand in mortar making, a more rapid hardening being thus secured, a matter of great moment in building foundation walls.

Artificial stone is also manufactured from the granulated slag, and used for building purposes, furnishing warm dry houses of handsome appearance.

When stones for building with enamelled surfaces are required they are obtained in some parts of Europe as follows:—The unburnt bricks are covered with granulated slag, and after drying are burnt in a furnace where they do not come in contact with carbon. The stones are completely glazed, and according to the different kinds of slag used are tinted of different colours. This operation is also employed advantageously with tiles, pipes, and earthenware.

If, in the preparation of fire-proof bricks, a certain proportion of mixture of clay and granulated slag be added to the mixture, very hard and durable fire bricks are obtained. These have been tested in a brass furnace, and experiments are being tried as to their applicability to building puddling furnaces. This granulated slag may also be advantageously used for manure. Blast furnace slag has also been drawn out in fine threads or filaments, furnishing the so-called ‘furnace wool.’ This substance, being a very bad conductor of heat, has suggested various household and other uses. A cheap and valuable cement, said to be equal to Portland cement, has been prepared from the finely granulated slag, which will also resist well the action of acids.

Mr Britten in 1876 patented a process for the manufacture of glass from blast furnace slag. Large works for the purpose of carrying out this invention, under the title of ‘Britten’s Patent Glass Company,’ have been erected at Finedon in Northamptonshire, and are, we believe, successfully worked in manufacturing glass bottles.

The method consists in removing molten slag in a ladle from the blast furnace, and pouring into a Siemen’s furnace, when certain amounts of carbonate of sodium and silica are added, depending upon the quality of the slag used, and of the glass required.

SLATE. The excellence of this material for water cisterns deserves a passing notice here.

Irish slate (Lapis Hibernicus) is an argillaceous mineral, said to contain iron and sulphur, found in different parts of Ireland. It is a common remedy, among the vulgar, for internal bruises, taken in a glass of gin.

SLEEP. During the period of our waking hours the exercise of the animal functions entails a waste or destruction of tissue in the organs performing them, which, unless duly repaired, would soon lead to the enfeeblement and consequent failure of the powers of the organs themselves. For the animal economy therefore to be maintained in a state of efficiency the repair of the reduced tissues is a necessity; and this essential condition is effected by the agency of sleep, during which respiration, circulation, digestion, &c., continue to be carried on simultaneously with assimilative processes which end in the regeneration of the impaired tissue.

A proper amount of sleep is therefore as great or even a greater necessity than a proper supply of food; and any one failing to obtain it soon perishes of exhaustion. Thus it is that any great mental emotion—such as intense remorse, grief, anxiety, or the depressing effect of a reverse of fortune—so frequently expedites death. Like Macbeth “it murders sleep,” one of the great needs of man’s existence.

Infants and children it is well known require much more sleep than adults. In these latter the organism, being already matured, demands only so much sleep as will enable it to make up for the daily waste of the body, which waste falls very far below the amount of nutrition required by the growing infant. In a still earlier state of development, viz., the fœtal one, life may be said to be passed entirely in slumber; whilst children prematurely born scarcely ever wake except for food. We may assume that, as a general rule, infants take treble the amount of sleep that adults do, and that very young infants thrive the better the larger the amount of sleep they get, is borne out by the experience of medical practitioners, who affirm that they have known many children who were born small and weakly, but who slept the greatest part of their early existence, afterwards became strong and healthy; whilst those children on the contrary who, being born large and strong, were not good sleepers, became subsequently enfeebled and unhealthy. As regards the sleep of adults, if the slumber has been of average length, or the subject of it awakes fully refreshed therefrom, a second sleep instead of being conducive is prejudicial to health, and should never be encouraged.

During sickness a patient, if in a very helpless and enfeebled state, may often be exposed whilst asleep to great peril, unless the nurse who attends him exercises intelligence and a proper amount of vigilance. In his work on ‘Household Medicine’ Dr Gardner has pointed out the dangers that beset the sleeping patient, and the means by which they may be avoided. “Having disposed,” he says, “of the patient in bed in the best manner, be careful that no part of the pillow can project over the mouth or nose, and that the bedclothes do not cover the mouth.

“The attendant should be particularly attentive to these points, when a narcotic has been taken, when the disease is paralysis, fever, head diseases, bronchitis, or any pulmonary complaint. The patient should be watched until he sleeps, and during his sleep, if a nurse is not constantly present, should be visited frequently, to observe whether the mouth and nostrils are free, and nothing obstructs the breathing.

“Very little suffices for an obstruction in such cases, which may extinguish life. Hundreds, perhaps we may say thousands of persons die prematurely from suffocation during sleep, in a low condition of the vital energies.

“How often does it happen that a patient left in a calm sleep is found dead upon being visited an hour or two after. Soft yielding pillows, in which the head and face get buried, are the instruments of suffocation to weakly persons, very, very often.”

The larger amount of sleep indulged in by the very old, over adults, is referable to the incapacity of the aged for exercise, and to their enfeebled powers of nutrition. Besides age, temperament, habit, and surrounding circumstances exercise considerable influence on the amount of sleep necessary for man. Persons of lymphatic temperament are generally great sleepers; whilst those of a nervous and active nature are mostly the reverse. The late Earl Russell was we believe in the years of his active political life a very small sleeper, his slumbers seldom extending over five hours. So, likewise was the Duke of Wellington; General Elliott, the defender of Gibraltar, seldom slept more than four hours out of the twenty-four. As a contrast to these cases may be mentioned that of Dr Reid, the metaphysician, of whom it is stated that he could take as sufficient food and afterwards as much sleep as would suffice for an ordinary man for two days.

Several well-attested cases of excessive slumber are on record in which the sleep lasted in some cases for weeks, and in others even for months.

In the ‘Comptes Rendus’ for 1864 Dr Blanchet records the case of one of his patients, a lady of 24 years of age, who had slept for 40 days when she was 18 years of age. Two years later she had a sleep lasting 50 days. Upon a subsequent occasion she fell asleep on Easter Sunday, 1862, and did not wake till March, 1863. She was fed during this period with milk and soup. She continued motionless and insensible, the pulse was low, the breathing scarcely perceptible, there were no evacuations, and she betrayed no signs of wasting away, whilst her complexion is described as florid and healthy.

This, however, as well as other cases of a similar kind, must not be regarded as an extreme instance of healthy slumber, but as a form of lethargy or coma, as indicative of disease, as the opposite condition or sleeplessness, that is frequently an accompaniment of certain forms of fevers, inflammatory affections, and brain disorders.

Mr Durham, of Guy’s Hospital, seems to have disposed of the condition that sleep is caused by the pressure of the distended veins on the brain.

A piece of bone being removed from a dog’s skull so that the animal’s brain could be observed when sleeping, it was found, 1, the veins were not distended. 2. During sleep the brain is in a comparatively bloodless condition, and the blood in the encephalic vessels is not only diminished in quantity, but moves with diminished rapidity; and this is corroborated by the observations of Dr Hughlings Jackson on the ophthalmoscopic condition of the retina during sleep, the optic disk being then whiter, the arteries smaller, and the retina generally more anæmic than in the waking state. 3. The condition of the cerebral circulation during sleep is from physical causes, that which is most favorable to the nutrition of the brain tissue. See Bed, Watchfulness.

SLEEPLESSNESS AND COLD FEET. The association betwixt cold feet and sleeplessness is much closer than is commonly imagined. Persons with cold feet rarely sleep well, especially women. Yet the number of persons so troubled is considerable. We now know that if the blood-supply to the brain be kept up, sleep is impossible. An old theologian, when weary and sleepy with much writing, found that he could keep his brain active by immersing his feet in cold water; the cold drove the blood from the feet to the head.

Now, what this old gentleman accomplished by design is secured for many persons much against their will. Cold feet are the bane of many women. Light boots keep up a bloodless condition of the feet in the day, and in many women there is no subsequent dilatation of the blood-vessels when the boots are taken off. These women come in from a walk and put their feet to the fire to warm—the most effective plan of cultivating chilblains. At night they put their feet to the fire, and have a hot bottle in bed. But it is all of no use; their feet still remain cold. How to get their feet warm is the great question of life with them—in cold weather. The effective plan is not very attractive at first sight to many minds. It consists in first driving the blood-vessels into firm contraction, after which secondary dilatation follows. See the snowballer’s hands! The first contact of the snow makes the hands terribly cold; for the small arteries are driven thereby into firm contraction, and the nerve-endings of the finger-tips feel the low temperature very keenly. But as the snowballer perseveres, his hands commence to glow; the blood-vessels have become secondarily dilated, and the rush of warm arterial blood is felt agreeably by the peripheral nerve-endings. This is the plan to adopt with cold feet. They should be dipped in cold water for a brief period; often just to immerse them, and no more, is sufficient; and then they should be rubbed with a pair of hair flesh gloves, or a rough Turkish towel, till they glow, immediately before getting into bed. After this a hot-water bottle will be successful enough in maintaining the temperature of the feet, though without this preliminary it is impotent to do so. Disagreeable as the plan at first sight may appear, it is efficient; and those who have once fairly tried it continue it, and find that they have put an end to their bad nights and cold feet. Pills, potions, lozenges, “night-caps,” all narcotics, fail to enable the sufferer to woo sleep successfully: get rid of the cold feet, and then sleep will come of itself.—British Medical Journal.

SMALLPOX. See Pox.

Smallpox in Sheep. Syn. Variola ovina. This disease, although bearing the same name as that which attacks the human subject, is a perfectly distinct malady, and incapable of being communicated to man either by inoculation or contagion. In about ten days from the time of the animal’s having imbibed the contagion feverish symptoms set in accompanied with a mucous discharge of a purulent character from the nose. Red inflammatory pimples then begin to develop, first appearing where the skin is thin. After the pimples have been out about three days they assume a white appearance, and are filled with serum and pus. “Some of the vessels dry up, leaving brown scabs; others, especially in the severer cases, run together, and the scarf skin is detached, leaving an ulcerated surface. It is in this ulcerated stage that the prostration reaches its height, and that most sheep die. The mortality from smallpox in sheep ranges from 25 to 90 per cent.”

The disease being a very infectious one, the affected animals must be kept separate from the healthy ones. Thirty grains of chlorate of potash should be given three times a day, whilst the food should be nutritious and such as to tempt the animal’s appetite. It may consist of bruised oilcake, bran, and steeped oats. Professor Simonds recommends inoculation as a prophylactic measure.

Smallpox Marks, Prevention of. 1. For preventing disfigurement from smallpox marks, Dr Bernard suggests that the pustules as soon as they have acquired a certain size should be punctured with a fine needle, and then repeatedly washed with tepid water.

2. Dr Thorburn Patterson prescribes the following ointment:—Carbonic acid, 20 to 30 minims; glycerine, 1⁄2 dr.; ointment of oxide of zinc, 6 dr.

3. Cream smeared on the pustules, frequently during the day, with a feather. See also Ointments.

SMALTS. Syn. Azure, Powder blue, Siliceous b., Smalt, Azurum, Smalta, L. This consists, essentially, of glass coloured by fusing it with oxide of cobalt.

Prep. 1. Cobalt ore is roasted, to drive off the arsenic, then made into a paste with oil of vitriol, and heated to redness for an hour; the residuum is powdered, dissolved in water, and the ferric oxide precipitated with carbonate of potassium, gradually added, until a rose-coloured powder begins to fall; the clear portion is then decanted, and precipitated with a solution of silicate of potassium (prepared by fusing together, for 5 hours, a mixture of 10 parts of potash, 15 parts of finely ground flints, and 1 part of charcoal); the precipitate after being dried is fused, and reduced to a very fine powder. A very rich colour.

2. Roasted cobalt ore and carbonate of potassium, of each 1 part; siliceous sand, 3 parts; fuse them together, and cool and powder the residuum. Used as a blue pigment, also to colour glass, and for ‘blueing’ the starch used to get up linen. See Blue pigments.

SMELL′ING SALTS. See Salts, Smelling.

SMELT. A beautiful little abdominal fish abounding in the Thames, and a few other rivers, between the months of November and February. It is esteemed a great delicacy by epicures, but sometimes proves offensive to the delicate and dyspeptic.

SMOKE PREVEN′TION. Although the full consideration of this subject belongs to public hygiene and civil engineering, its immediate application and advantages are interesting and important to everybody.

The history of smoke burning scarcely commences before the year 1840, at which date Mr Charles Wye Williams obtained a patent for this purpose. Since that time a ‘thousand-and-one’ schemes, either patented or non-patented, professedly for the same object, have been brought before the public. Most of these have been supported by the most reckless statements regarding their value, made by interested parties; and the most serious inconvenience and losses have often followed their adoption. Williams’s method is to admit an abundant supply of cold air through a large number of small perforations in the door and front part of the furnace. Lark’s method is based on the admission of heated air, under due regulation, both through the door, and at the bridge or back of the furnace, by which means combustion is rendered more complete, and smoke thereby prevented.

Ivison’s plan consists in the introduction of steam by minute jets over the fire, which is thus greatly increased in intensity without the production of smoke, and with a saving of fuel. In Jucke’s arrangement the grate bars of a furnace are replaced by an endless chain web, which is carried round upon two rollers, in such a way that each part of the fuel is exposed to conditions most favorable for perfect combustion. Other inventions are based upon supplying fuel to the fires from beneath, so that the products of combustion must pass through the incandescent coals above.

For household fires, the smokeless grate, invented by Dr Arnott, will be found entirely successful, and most economical. Its general introduction would be a great advance in both domestic and public hygiene; and, being hence of national importance, should be enforced by law.

SMO′′KING. This is done, on the large scale, by hanging up the articles (previously more or less salted) in smoking rooms, into which smoke is very slowly admitted from smothered dry-wood fires, kindled in the cellar, for the purpose of allowing it to cool and deposit its cruder part before it arrives at the meat. This process requires from six days to as many weeks to perform it properly, and is best done in winter. In farm-houses, where dry wood is burnt, hams, &c., are often smoked by hanging them up in some cool part of the kitchen chimney. When the meat is cut into slices, or scored deeply with a knife, to allow the smoke to penetrate it, it is called ‘BUCANING,’

“The quality of the wood has an influence upon the smell and taste of the smoke-dried meat; smoke from beech wood and oak being preferable to that from fir and larch. Smoke from the twigs and berries of juniper, from rosemary, peppermint, &c., impart somewhat of the aromatic flavour of these plants.” (Ure.) The occasional addition of a few cloves or allspice to the fuel gives a very agreeable flavour to the meat.

Hung beef, a highly esteemed variety of smoked beef, is prepared from any part, free from bone and fat, by well salting and pressing it, and then drying and smoking it in the usual manner. It is best eaten shredded. See Putrefaction, Salting, &c.

SNAKE-POISONING, Mortality from. The ‘Lancet’ quoting a letter from T. B. Beighton, Esq., of the Bengal Civil Service, magistrate of the Culna district of the Burdwan province of Bengal, says:—“The Culna district comprises, we presume, 80 or 100 square miles, and has a population of about 300,000. Mr Beighton says that deaths from snakebite are singularly common in the subdivision. An average of one per day is reported through the police. The actual deaths are probably double the number reported. If this daily average is meant to apply the whole year round, we should thus get in a comparatively small district the frightful death of 700 persons from snakebite. It is lamentable to think that despite the supposed remedial discoveries in this direction, we still seem to be without an agent to neutralise the effects of the bites of poisonous snakes.”

SNAKE-ROOT. See Senega. For ‘Virginian snake-root’ see Serpentary. Snakeweed (Bistortæ radix) is the root of Polygonum Bistorta (Linn.).

SNIPE. The Scolopax Gallinago, a well-known bird indigenous to this country. It is fine-flavoured, but rather indigestible.

SNOW, Foreign Bodies in. M. Bondier having lately made an examination of snow, records that of the solid matters floating in the air and retained in the snow, the most abundant was found to be soot; next some cells of Protococcus virictis, and spores and filaments of other cryptograms; then granules of starch and cells and fibres of various plants. Epithelial cells and hairs of animals were also present, as well as fibres of wool and silk. These last, being dyed, indicated the presence of man, as did also the fibres of hemp, cotton, and indigo. The amount of foreign matter was greatest in the snow collected at the lowest levels, especially in the vicinity of human habitations and of woods, which are both fertile sources of floating particles. Permanganate of potassium was used to estimate the amount of organic matter dissolved by the filtered snow water.

Immediately mixed with the soot were the ferruginous corpuscles observed by Tissandier. These are regarded by the author, in opposition to the opinion of Tissandier, as of terrestrial origin.

SNUFF. Syn. Pulvis tabaci, L.; Tabac en poudre, Fr. A powder, prepared from tobacco, for the purpose of being sniffed up the nose as a stimulant or intoxicant.

The finer kinds of snuff are made from the soft portions of the best description of manufactured leaf-tobacco, separated from the damaged portion; but the ordinary snuffs of the shops are mostly prepared from the coarser and damaged portions, the mid-ribs, stems, or stalky parts that remain from the manufacture of ‘shag tobacco,’ the dust or powder sifted from the bales, and the fragments that are unfit for other purposes.

Prep. The proper material being chosen, and if not in a sufficiently mature state rendered so by further fermentation, they are sufficiently dried by a gentle heat or exposure to the air to admit of being pulverised. This is performed, on the large scale, in a mill, and on the small scale, with a kind of pestle and mortar. During the operation the tobacco is frequently sifted, that it may not be reduced to too fine a powder, and is several times slightly moistened with rose or orange-flower water, or eau d’ange, which are the only liquids fit for the superior kinds of snuff. In preparing the dry snuffs no moisture is used. The scent or other like matters are next added, and, after thorough admixture, the snuff is packed in jars or canisters.

Adult. During the grinding of tobacco it is frequently mixed with dark-coloured rotten wood, various English leaves, colouring, and other matter. Ammonia, hellebore, euphorbium, and powdered glass are common additions to snuffs to increase their pungency. We have seen powdered sal ammoniac sent by the hundredweight at one time to a certain celebrated London tobacconist. The moist kinds of snuff are generally drugged with pearlash, for the triple purpose of keeping them damp and increasing their pungency and colour. The dry snuffs, especially ‘Scotch’ and ‘Welsh,’ are commonly adulterated with quicklime, the particles of which may be occasionally distinguished even by the naked eye. This addition causes their biting and desiccating effect on the pituitary membrane. “We were once severely injured by taking snuff which, after our suspicions were awakened, we found to contain a mixture of red lead and umber.” (Cooley.)

The following circumstance related by Dr Garrod in a lecture at King’s College Hospital leads to the inference that the custom of packing snuff in lead is not free from danger. The doctor says:—A gentleman, a resident in India, began to suffer some time since from nervous exhaustion, anæmia, and debility of both extremities; he was a great snuff taker, taking on an average as much as an ounce in the course of a day. He consulted several medical men in India, and they attributed his symptoms to inordinate snuff taking. He, however, continued to take snuff and to get worse, and at last came to England to seek further advice. When Dr Garrod saw him he discovered a blue line on the gums. His suspicions were directed to the snuff, which he found to contain a considerable quantity of lead. To ascertain whether or not the presence of lead in this circumstance was an accidental circumstance, six packets were ordered from the house in Calcutta with which the gentleman had been in the habit of dealing. The snuff was contained in sheet-lead packages, which were all found to contain lead to about the same extent as the first specimen. Dr Garrod exhibited a solution, which he tested in the following way:—Ten grains of snuff were burned in a platinum crucible, and the ash was treated with nitric acid, the crystallised result was dissolved in water with the addition of a small quantity of acetic acid, and then tested with iodide of potassium, which threw down an abundant precipitate of yellow iodide of lead. The leaden packages were labelled ‘best brown rappee,’ and bore the name of a well-known English firm, from which they had been exported to India. The snuff itself was rather moist. Where it adhered to the sides of the case it was dotted with white spots, probably consisting of carbonate of lead, formed by, Dr Garrod suggests, the fermentation of the damp snuff.

Since Dr Garrod’s attention has been directed to this subject, he has spoken to a medical man recently returned from Calcutta, who told him that he had quite lately met with three cases of lead-poisoning, which, on investigation, were found to be due to the use of snuff.

Var. Snuffs are divided into two kinds—DRY SNUFFS, as ‘Scotch,’ ‘Irish,’ ‘Welsh,’ and ‘Spanish snuff,’ ‘Lundyfoot,’ &c.; and MOIST SNUFFS, or RAPPEES, including ‘black’ and ‘brown rappee,’ ‘carrotte,’ ‘Cuba,’ ‘Hardham’s mixture,’ ‘prince’s mixture,’ ‘princeza,’ ‘queen’s snuff,’ &c. The last three also come under the denomination of SCENTED SNUFFS.

The immense variety of snuffs kept in the shops, independently of the above-named conditions, depend for their distinguishing characteristics on the length of the fermentation, the fineness of the powder, the height to which they are dried, and the addition of odorous substances. Tonquin beans, essence of tonquin bean, ambergris, musk, civet, leaves of orchis fusca, root and oil of calamus aromaticus, powder and essence of orris root, and the essences or oils of bergamot, cedra, cloves, lavender, petit grain, neroli, and roses (otto), as well as several others, either alone or compounded, are thus employed. Tabac parfumée aux fleurs is perfumed by putting orange flowers, jasmins, tuberoses, musk roses, or common roses, to the snuff in a close chest or jar, sifting them out after 24 hours, and repeating the treatment with fresh flowers, as necessary. Another way is to lay paper, pricked all over with a large pin, between the flowers and the snuff.

Macouba snuff is imitated by moistening the tobacco with a mixture of treacle and water, and allowing it to ferment well.

Spanish snuff is made from unsifted ‘Havannah snuff,’ reduced by adding ground Spanish nutshells, sprinkling the mixture with treacle water, and allowing it to sweat for some days before packing.

Yellow snuff is prepared from ordinary pale snuff moistened with a mixture of yellow ochre diffused in water, to which a few spoonfuls of thin mucilage have been added; when dry, the colour that does not adhere to the snuff is separated with a fine sieve.

Red Snuff. As last, but using red ochre.

Snuff, Asarabac′ca. Syn. Cephalic snuff, Compound powder of asarabacca; Pulvis asari compositus, L. Prep. 1. (Ph. D. 1826.) Asarabacca leaves, 1 oz.; lavender flowers, 1 dr. (both dried); mix and powder them.

2. (Ph. E. 1817.) Asarabacca leaves, 3 dr.; leaves of marjoram and flowers of lavender, of each 1 dr.; as before. Both are used as errhines in headaches and ophthalmia. See Snuff, Cephalic, Asarabacca, &c.

Snuff, Cephal′ic. Prep. 1. From asarabacca leaves and Lundyfoot snuff, of each 2 oz.; lavender flowers, ⁄4 oz.; essence of bergamotte and oil of cloves, of each 2 or 3 drops; mixed and ground to a powder, the perfume being added last.

2. (Boeli’s.) From tobacco or pure snuff and valerian root, of each ⁄2 oz.; reduced to powder, and scented with the oils of lavender and marjoram, of each 5 or 6 drops.

Obs. The first formula is an excellent one; and the product is very useful in nervous headaches, dimness of sight, &c. See Snuff, Asarabacca (above).

Snuff, Eye. Prep. From finely levigated tribasic sulphate of mercury (‘Turpeth mineral’), ⁄2 dr.; pure dry Scotch or Lundyfoot snuff, 1 oz.; triturate them well together. A pinch of this, occasionally, has been recommended in inflammation of the eyes, dimness of sight, headache, polypus, &c.; but it should be used with caution, and not too often.

SOAP. Syn. Sapo, L.; Savon, Fr. Spanish, Castile, or HARD SOAP, made with olive oil and soda (SAPO, SAPO EX OLIVÆ OLEO ET SODÂ CONFECTUS—Ph. L.; SAPO DURUS—B. P., Ph. E., & D.), and SOFT SOAP, made with olive oil and potash (SAPO MOLLIS—B. P., Ph. L., & E., SAPO EX OLIVÆ OLEO ET POTASSÂ CONFECTUS—Ph. L.), are the only kinds directed to be employed in medicine. The former is intended whenever ‘soap’ is ordered, and is the one which is principally employed internally; the latter is used in ointments, &c., and in some of the officinal pills.

Prep. The fatty or oleaginous matter is boiled with a weak alkaline lye (soap-lye) rendered caustic by quicklime, and portions of stronger lye are added from time to time, the ebullition being still continued, until these substances, reacting on each other, combine to form a tenacious compound, which begins to separate from the water; to promote this separation and the granulation of the newly-formed soap, some common salt is generally added, and the fire being withdrawn, the contents of the boiler are allowed to repose for some hours, in order that the soap may collect into one stratum, and solidify; when this happens it is put into wooden frames or moulds, and when it has become stiff enough to be handled it is cut into bars or pieces, and exposed to the air, in a warm situation, to further harden and to dry.

In the print works of Alsace, where an immense quantity of egg albumen is consumed, there collect, as a necessary result, enormous quantities of the yolks of egg. Amongst other purposes to which these are applied that of soap-making is one. According to Kingzett, the olein is not the only ingredient of the yolk which reacts upon the soda or potash, and thus produces soap; but the yolk also contains another body, which, absorbing water under the influence of the bases, splits up into oleic and margaric acids.

“Besides the olein contained in the free state, there is,” says Mr Kingzett, “present a body called lecithine of the formula C42H84NPO9.” Gobloy, Diakonow, Strecker, Thudicum, and Kingzett have studied this substance, and express its chemolysis as follows:—

Lecithine. Water. Glycero-phosphoric acid.

C42H84NPO9 - 3H2O = C3H9PO6

Choline. Oleic acid. Palmitic acid.

+ C5H15NO2 + C18H34O2 + C16H32O2.

That is to say, bases have the power, by abstracting water, to split up lecithine into, among other products, oleic and palmitic acid; so that when eggs are used for soap-making this process actually occurs, the soda or potash employed being sufficient to effect the necessary decomposition, and the resulting soap being, therefore, the product from not only the olein, but from the fatty acids so formed.

Tessie du Mothay has proposed a method for the recovery of potash, soda, &c., from soap water, which is as follows:—He decomposes the soap water by calcium, barium, or magnesium carbonate, and then passes carbonic acid through the liquid. The bicarbonate form precipitates organic matter and other impurities, and these settle down. The solution is then evaporated or treated with baryta water, which precipitates the last portion of foreign matters, and leaves a solution of caustic alkali. At a particular stage of the process an acid is used in order to hasten the separation of the resinous substances, and, in certain cases, of the sulphides of sodium and calcium, or barium and calcium and ferric oxide, and then passes carbonic acid into the liquid. The precipitated metallic substances carry down with them the humus-like substances present.

Var. The principal varieties of soap found in commerce are:—

Almond Soap (Sapo amygdalinus), made from almond oil and caustic soda, and chiefly used for the toilet.

The P. Codex gives the following formula for its preparation:—Solution of caustic soda (1·334), by weight, 10 oz.; oil of almonds, by weight, 21 oz.; add the lye to the oil in small portions, stirring frequently; leave the mixture for some days at a temperature of from 64° to 68° Fahr., stirring occasionally, and when it has acquired the consistence of a soft paste, put it into moulds until sufficiently solidified. It should be exposed to the air for one or two months before it is used.

Animal Soap. Sapo animalis, Curd soap (B. P.). A soap made with soda and a purified animal fat consisting principally of stearin (P. Cod.). Put 5 parts of beef marrow with 10 parts of water into a porcelain or silver basin, heat, and when melted add by portions, with constant stirring, 2⁄2 parts of liquor sodæ (1·33); when saponified, add 1 part of salt; stir, remove the soap from the surface, drain it, melt it with a gentle heat, and pour it into moulds.

Castile Soap, Spanish s., Marseilles s.; Sapo Castiliensis, Sapo Hispanicus. An olive-oil soda soap, kept both in the white and marbled state. The former is said to be the purest, the latter the strongest.

Curd Soap, made with tallow (chiefly) and soda (see above).

Medicated Soaps, containing various active ingredients. The chief of these are noticed below.

Mottled Soap, made with refuse kitchen-stuff, &c.

Soft Soap (of commerce), made with whale, seal, or cod oil, tallow, and caustic potash.

N. Gräger gives the following method for the easy determination of the fat and alkali in soft (potash) soaps:—25 to 50 grammes of soap are dissolved in 150 c.c. of water by aid of heat, cooled, and mixed with an excess of salt, so that a soda-soap separates out; the latter is washed on a paper filter with a saturated solution of salt. In the filtrate the free alkali is estimated by a normal acid. The precipitate is decomposed by warming with excess of normal acid, and the quantity of acid neutralised by the combined alkali, determined by a standard soda solution. The cake of fat which separates in the last operation, is dried and weighed after adding to it, while melted, a known weight of stearin or paraffin to give it hardness.

Toilet Soaps, prepared from any of the preceding varieties, and variously coloured and scented. Formulæ are given below.

Yellow Soap, Resin soap, made with tallow, resin, and caustic soda. Soluble glass is now largely employed in place of resin.

Soaps are also divided into SOFT or POTASH SOAPS, and HARD or SODA SOAPS.

Assay. 1. For the WATER. A piece, fairly taken from the sample, and weighing 100 gr., is reduced to thin shavings, which are dried by the heat of boiling water, until they cease to lose weight. The loss indicates the proportion of free water. This should not exceed 35% for ordinary curd and mottled soap, 45% for yellow soap, and about 15% to 16% for Castile soap.

2. For the ALKALI. 100 gr. of the soap are dissolved in 4 or 5 fl. oz. of boiling water, and the solution tested by the common method of alkalimetry. Curd and yellow soap usually contain from 6% to 7%, mottled soap from 7% to 8%, and Castile soap 8% to 9% of soda.

3. For the OIL or FAT. The solution tested for alkali (see No. 2) is heated, and then allowed to cool slowly; when cold the floating fatty matter is removed, freed from water, and weighed. When the fat or oil has little consistence, 100 gr. of pure white wax is added to the soap solution before heating it. The weight obtained, in grains in the one case, and the excess above 100 gr. in the other, give the proportion of oil or fat present. This, in ordinary mottled soap, should be about 68%; in yellow soap, 65%; in curd soap, 60%; and in Castile soap, 75%.

4. Unsaponified fatty matter.—a. Pure soap is entirely soluble in distilled water and insoluble in saline solution; if a film of fatty matter forms on its solution in the former, after repose, that portion has not been saponified.

b. The fat separated from soap (see No. 2), when it has been perfectly saponified, is entirely soluble in alcohol.

5. Other impurities. Pure soap is soluble in rectified spirit, forming a colourless or nearly colourless solution. The undissolved portion, if exceeding 1%, is adulteration.

Another Method of Soap Assay (M. Moffit). The constituents to be determined in an analysis of soap are alkalies (combined and free), carbonates, fatty acids, resin, glycerin, salts, colouring matters, and water.

Three portions of the finely divided soap are weighed off, containing respectively 10 grams, 20 grams, and 40 grams. Ten grams are digested with alcohol on the water-bath and filtered. The residue containing carbonates and other salts, colouring matter, &c., is dried at 100°, weighed, digested with water, and titrated with normal oxalic acid. Every c.c. of acid used indicates 0·053 Na2CO3.

Regard must be had to a slight precipitate of calcium oxalate. The weight of Na2CO3 found is subtracted from the total residue insoluble in alcohol, the difference is the weight of the salts and foreign matters. The filtrate is subjected to a stream of carbonic acid, filtered, and the precipitate dissolved in water and titrated with oxalic acid. Each c.c. of acid indicates 0·031 free soda, or 0·042 free potash. No precipitate shows the absence of free alkalies. The filtrate from the precipitate produced by the carbonic acid is, after the addition of 15 c.c. of water, evaporated to remove the alcohol. The aqueous solution, treated with normal oxalic acid to acid reaction, shows for every c.c. of acid 0·031 soda, or 0·042 potash in combination. Sulphuric acid is then added, and the whole is heated on a water bath with pure beeswax to separate the fatty acids and resin, which are then weighed, the weight of the beeswax being subtracted.

Forty grams of the soap are next dissolved in water and mixed with sulphuric acid, as long as any precipitate is formed. On standing the fatty acids separate, and can be dried and weighed. These fatty acids are digested with a mixture of equal volumes of water and alcohol, till the liquid on cooling ceases to appear milky. The solid layer is again weighed, and the difference between the weight and that obtained above shows the weight of the resin.

The melting point of the acids is next determined. Ten grams are then dissolved in alcohol, and sulphuric acid diluted with alcohol is added, till a precipitate is no longer formed. The liquid is filtered, mixed with barium carbonate, and again filtered. The sweet residue left after evaporation of the alcohol is glycerin. The weights of the carbonates, salts, and foreign matters, free and combined alkalies, fatty acids, resin, and glycerin are added together, and the sum subtracted from 10 grams gives the weight of the water.

See also Soap analysis, ‘Chem. News,’ xxxv, 2. The article is too long to allow of insertion here.

Uses, &c. The common uses of soap need not be enumerated. As a medicine it acts as a mild purgative and lithontriptic, and it has been thought by some to be useful in certain affections of the stomach arising from deficiency of bile. Externally it is stimulant and detergent.—Dose, 3 to 20 or 30 gr., made into pills, and usually combined with aloes or rhubarb.

Concluding Remarks. Prior to the researches of Chevreul, no correct ideas were entertained as to the constitution of soap. It was long known that the fixed oils and fats, in contact with caustic alkaline solutions at a high temperature, undergo the remarkable change which is called saponification; but here the knowledge of the matter stopped. Chevreul discovered that if the soap, so produced, be afterwards decomposed by the addition of an acid, the fat which separates is found to be completely changed in character; to have acquired a strong acid reaction when applied in a melted state to test paper, and to have become soluble with the greatest facility in warm alcohol; in other words—that a new substance, capable of forming salts, and exhibiting all the characteristic properties of an acid, has been generated out of the elements of the neutral fat under the influence of the base. Stearin, when thus treated, yields stearic acid, palmitin gives palmitic acid, olein gives oleic acid, and common animal fat, which is a mixture of several neutral bodies, affords, by saponification by an alkali and subsequent decomposition of the soap, a mixture of the corresponding fatty acids. These bodies are not, however, the only products of saponification; the change is always accompanied by the formation of a very peculiar sweet substance called glycerin, which remains in the mother liquor from which the acidified fat has been separated. The process of saponification itself proceeds with perfect facility, even in a closed vessel; no gas is disengaged; the neutral fat, of whatsoever kind, is simply resolved into an alkaline salt of the fatty acid, which is soap, and into glycerin, a neutral body resembling syrup, and, like that liquid, miscible with water in every proportion.

“When yellow soap is made with the cheaper kinds of fat it will hardly acquire a sufficient degree of firmness or hardness to satisfy the thrifty washerwoman. It melts away too rapidly in hot water, a defect which may be well remedied by the introduction into the soap of a little (1·20th) fused sulphate of soda; and this salt concreting gives the soap a desirable hardness, whilst it improves its colour, and renders it a more desirable article for the washing tub.” (Ure.) This process was patented by Dr Normandy, but soon proved a source of annoyance and molestation to him on the part of the Board of Excise, it being an enormous crime in law to attempt to improve and cheapen soap.

“Soda which contains sulphurets is preferred for making mottled or marble soap, whereas the desulphuretted soda makes the best white curd soap.” “The Barillas always contain a small proportion of potash, to which their peculiar value, in making a less brittle or more plastic hard soap than the factitious sodas, may, with great probability, be ascribed.” (Ure.)

The mottled appearance is usually given, in the London Soap-works, by watering the nearly finished soap with a strong lye of crude soda, by means of a watering can furnished with a rose spout. For ‘Castile soap’ a solution of sulphate of iron is so employed. See Soaps (Medicated and Toilet).

Soap, Arsen′ical. Syn. Sapo arsenicalis, L. Prep. (Bécœurs.) From carbonate of potash, 12 oz.; white arsenic, white soap, and air-slaked lime, of each 4 oz.; powdered camphor, ⁄4 oz.; made into a paste with water, q. s. Used to preserve the skins of birds, and other small animals.

Soap, Black. Syn. Sapo niger, S. mollis communis, L. A crude soft soap, made of fish oil and potash; but the following mixture is usually sold for it:—Soft soap, 7 lbs.; train oil, 1 lb.; water, 1 gall.; boil to a proper consistence, adding ivory black or powdered charcoal, q. s., to colour. Used by farriers.

SOAPS (Med′icated). A few only of these deserve notice here:—

Soap, Antimo′′nial. Syn. Sapo antimonialis, Sapo stibiatus, L. Prep. (Hamb. Cod. 1845.) Golden sulphuret of antimony, 2 dr.; solution of caustic potassa, 6 dr. (or q. s.); dissolve and triturate the solution with medicated (Castile) soap (in powder), 1⁄2 oz., until the mass assumes a pilular consistence. It should be of a greyish-white colour.

Soap, Chlorina′ted. Syn. Sapo calcis chlorinatæ, L.; Savon antisyphilitique, Fr. Prep. From Castile soap (in powder), 11 oz.; chloride of lime (dry and good), 1 oz.; mix, beat them to a mass with rectified spirit, q. s.; (holding in solution) oil of verbena or of ginger grass, ⁄4 oz.; lastly, form the mass into flat tablets, and wrap these in thin sheet gutta percha. A most excellent detergent and stimulant soap in various affections, admirably adapted for hospital use, and for removing stains from the skin and rendering it white. It is the most powerful known agent against infection from contagious diseases communicable by contact.

Soap, Cod-Liver Oil. Syn. Sapo olei Jecoris (Deschamps). Prep. Cod-liver oil, 2 oz.; caustic soda, 2 dr.; water, 5 dr.; dissolve the soda in the water, and mix it with the oil. An ioduretted soap is made by mixing with the above, 1 dr. of iodide of potassium dissolved in 1 dr. of water.

Soap, Cro′ton. Syn. Sapo crotonis, L. Prep. From croton oil and liquor of potassa, equal parts; triturated together in a warm mortar until they combine. Cathartic.—Dose, 1 to 3 gr.

Soap of Gamboge. Syn. Sapo gambogiæ. (Soubeiran.) Prep. Mix 1 part of gamboge with 2 of soap, dissolve it with a little spirit, and evaporate to a pilular consistence.

Soap, of Gua′iacum. Syn. Sapo guaiaci, Sapo guaiacinus, L. Prep. (Ph. Bor.) Liquor of potassa, 1 oz.; water, 2 oz.; mix in a porcelain capsule, apply heat, and gradually add of resin of guaiacum (in powder), 6 dr., or as much as it will dissolve; next decant or filter, and evaporate to a pilular consistence.—Dose, 10 to 30 gr.; in chronic rheumatism, various skin diseases, &c.

Soap I′odine. Syn. Sapo ioduratus, L. Prep. From Castile soap (sliced), 1 lb.; iodide of potassium, 1 oz.; (dissolved in) water, 3 fl. oz.; melt them together in a glass or porcelain vessel, over a water bath. Excellent in various skin diseases; also as a common soap for scrofulous subjects.

Soap of Jal′ap. See Jalap, Soap of.

Soap, Larch. Syn. Sapo laricis. (Dr Moore.) Prep. Dissolve 12 oz. of white curd soap in 24 oz. of rose water on a steam bath. Infuse 4 oz. of wheat bran in 10 oz. of cold water for 24 hours, and express. Add to the last, 3 oz. of pure glycerin. Dissolve 6 dr. of extract of larch bark in 1 oz. of boiling water. Mix these solutions with the dissolved soap, evaporate over a steam bath to a proper consistence, and pour into moulds to cool. For the local treatment of psoriasis.

Soap, Macquer’s Acid. Syn. Sapo vitriolicus, L. Prep. From Castile soap, 4 oz.; softened by heat and a little water, and then continually triturated in a mortar with oil of vitriol (added drop by drop). Detergent. Used where alkalies would be prejudicial.

Soap, Marine. Patent. This is made by substituting cocoa nut oil for the fats and oils used in the manufacture of common soap. It has the advantage of forming a lather with salt water.

Soap, Mercu′′rial. Syn. Sapo hydrargyri. (M. Herbert.) 1. Prep. Dissolve 4 oz. of quicksilver in its weight of nitric acid without heat; melt in a porcelain basin by water bath 18 oz. of veal suet, and add the solution, stirring the mixture till the union is complete. To 5 oz. of this ointment, add 2 oz. of solution of caustic soda (1·33), porphyry slag, till a soap is formed, which is completely soluble in water. For external use, alone, or dissolved in water, in some cutaneous diseases.

2. Sapo mercurialis, L. Prep. (Sapo sublimatis corrosivi.) From Castile soap (in powder), 4 oz.; corrosive sublimate, 1 dr.; (dissolved in) rectified spirit, 1 fl. oz.; beaten to a uniform mass in a porcelain or wedgwood-ware mortar.

3. (Sapo hydrargyri, PRECIPITATI ALBI—Sir H. Marsh.) Prep. Beat 12 oz. of white Windsor soap in a marble mortar, add 1 dr. of rectified spirit, 2 dr. of white precipitate, and 10 drops of otto. Beat the whole to a uniform paste.

4. (Sapo hydrargyri, PRECIPITATI RUBRI—Sir H. Marsh.) From white Windsor soap, 2 oz.; nitric oxide of mercury (levigated), 1 dr.; otto of roses, 6 or 8 drops; (dissolved in) rectified spirit, 1 to 2 fl. dr.; as the last. Both the above are employed as stimulant detergents and repellants, in various skin diseases; also as SAVON ANTISYPHILITIQUE.

Soap of Subacetate of Lead. Syn. Sapo saturni (Bristol Infirmary). Prep. Boil 1 lb. of white soap in 4 pints of rain water; when the soap is dissolved add 1 oz. of camphor pulverised with spirit, and mixed with 2 oz. of liquid subacetate of lead, stir the whole till cold.

Soap, Sul′phuretted. Syn. Sapo sulphuris, Sapo sulphuratus, L. Prep. (Sir H. Marsh.) From white soap, 2 oz.; sublimed sulphur, ⁄4 oz.; beaten to a smooth paste in a marble mortar with 1 or 2 fl. dr. of rectified spirit strongly coloured with alkanet root, and holding in solution otto of roses, 10 or 12 drops. In itch and various other cutaneous diseases.

Soap, Tar. Syn. Sapo picis liquidæ, Sapo PICEUS, L. Prep. From tar, 1 part; liquor of potassa and soap (in shavings), of each 2 parts; beat them together until they unite. Stimulant. Used in psoriasis, lepra, &c.

Soap, Tur′pentine. Syn. Starkey’s soap; Sapo terebinthinæ, S. terebinthinatus, L.; Savon térébinthine, Fr. Prep. (P. Cod.) Subcarbonate of potash, oil of turpentine, and Venice turpentine, equal parts; triturate them together, in a warm mortar, with a little water, until they combine; put the product into paper moulds, and in a few days slice it, and preserve it in a well-stopped bottle.

SOAPS (Toilet). Of toilet soaps there are two principal varieties:—

1. (Hard.) The basis of these is, generally, a mixture of suet, 9 parts, and olive oil, 1 part, saponified by caustic soda; the product is variously scented and coloured. They are also made of white tallow, olive, almond, and palm-oil soaps, either alone or combined in various proportions, and scented.

2. (Soft.) The basis of these is a soap made of hog’s lard and potash, variously scented and coloured.

3. Guido Schnitzer, writing to ‘Dingler’s Journal’ (cciii, 129-132), says that the use of sodium silicate (ordinary water-glass) has proved of great value in the manufacture of palm oil and cocoa-nut oil soaps, as it increases their alkalinity, and gives to them greater hardness and durability. It is for these reasons the silicate is much used in the manufacture of toilette soaps.

He states that during the American war, when the price of resin soap reached a high price, sodium silicate was much used as a substitute in soap making. The soap is found to be the more active and durable in proportion to the amount of silica in the silicate.

Schnitzer made a series of experiments in order to discover a mixture which, on fusing, will yield a silicate as rich as possible in silica, without being insoluble in boiling water, and he found the following proportions yielded on fusion the best silicate for the above purposes:—

100 parts of soda ash (containing 91 per cent, of Na2CO3), and 180 of sand. In the solution of silicate obtained on treatment with boiling water, the proportion of the Na2O to the SiO2 would then be as 1 to 2·9.

After long boiling with water, there ordinarily remains a slimy residue, which, on boiling up with fresh dilute soda-lye for a long time, furnishes a concentrated solution of silicate. This residue, consisting of silica, with insoluble higher silicates, was boiled with soda solution at 6° Baume, and the solution concentrated to 40° Baume, when the proportion therein of Na2O to SiO2 was found to be as 1 to 1·, and on cooling those crystallised out, sodium silicate of the formula Na2SiO3 × 8H2O, in white foliated crystals.

On the small scale the perfume is generally added to the soap melted in a bright copper pan by the heat of a water bath; on the large scale it is mixed with the liquid soap, at the soap-maker’s, before the latter is poured into the frames.

The following are examples of a few of the leading toilet soaps:

Soap, Bitter Al′mond. Syn. Savon d’amande, Fr. Prep. From white tallow soap, 56 lbs.; essential oil of almonds, ⁄4 lb.; as before.

Savon au Bouquet. [Fr.] Prep. From tallow soap, 30 lbs.; olive-oil soap, 10 lbs.; essence of bergamot, 4 oz.; oils of cloves, sassafras, and thyme, of each 1 oz.; pure neroli, ⁄2 oz.; brown ochre (finely powdered), ⁄2 lb.; mixed as the last.

Soap, Cin′namon. Prep. From tallow soap, 14 lbs.; palm-oil soap, 7 lbs.; oil of cinnamon (cassia), 3 oz.; oil of sassafras and essence of bergamot, of each ⁄2 oz.; levigated yellow ochre, ⁄2 lb.

Soap, Float′ing. Prep. From good oil soap, 14 lbs.; water, 3 pints; melted together by the heat of a steam or water bath, and assiduously beaten until the mixture has at least doubled its volume, when it must be put into the frames, cooled, and cut into pieces. Any scent may be added.

Soap, Glycerin. Any mild toilet soap being liquefied, glycerin is intimately mixed with it in the proportion of from a 20th to a 25th of the weight of the soap. Sometimes a red, and others an orange tint is given to it. The scent usually consists of bergamot, or rose geranium, mixed with a little oil of cassia, to which sometimes a little oil of bitter almonds is added.

2. (Spon.) 40 lbs. of tallow, 40 lbs. of lard, and 20 lbs. of cocoa-nut oil, are saponified with 45 lbs. of soda lye, and 5 lbs. of potash lye, of 40° Baume, when the soap is to be made in the cold way. To the paste then add, pure glycerin 6 lbs., oil of Portugal, ⁄2 oz., oil of bergamot, ⁄3 oz., bitter almond oil, 5 oz., oil of vitivert, 3 oz.

Soap, Hon′ey. Prep. 1. From palm-oil soap and olive-oil soap, of each 1 part; curd soap, 3 parts; melted together and scented with the oil of verbena, rose-geranium, or ginger-grass.

2. From the finest bright-coloured yellow soap, scented with the oils of ginger-grass and bergamot.

Soap, Liquid Glycerin—Glycerinseife, Flüssige. Sesame or cotton-seed oil is saponified with sufficient caustic potash, and while moist is dissolved in six times its weight of spirit of wine. The solution is filtered, five-sixths of the spirit is distilled from a water bath, and the cooled residue is reduced to the consistence of thin honey, with a mixture of 2 parts glycerin and 1 part spirit. It is then perfumed.

Soap, Musk. 1. A good ox suet or tallow soap is generally used for the basis of this. The scent is composed of a mixture of essence of musk, with small quantities of the oils of bergamot, cinnamon, and cloves. The quantity of musk must be regulated by the amount of fragrance required. The soap is usually coloured with caramel.

2. Another kind is made with tallow and palm-oil soap, to which is added a mixture of the powders of cloves, roses, and gilliflowers, oil of bergamot, and essence of musk. The colouring matter is brown ochre.

Soap, Musk. As CINNAMON SOAP, but with essence of musk, supported with a little essence of bergamot and oil of cloves, as perfume, and burnt sugar, to colour.

Soap, Naples. From olive oil and potash.

Soap, Orange-flower. As Savon à la rose, with oil of neroli or essence de petit grain, supported with a little of the essence of ambergris and Portugal, for perfume.

Soap, Palm-oil. Syn. Violet soap. Made of palm oil and caustic soda lye. It has a pleasant odour of violets and a lively colour.

Soap, Pearl. Syn. Almond cream; Crême d’amandes, Fr. Prep. From a soap made of lard and caustic potash lye; when quite cold it is beaten in small portions at a time in a marble mortar, until it unites to form a homogeneous mass, or ‘pearls,’ as it is called; essence of bitter almonds, q. s., to perfume, being added during the pounding.

Savon à la Rose. [Fr.] Prep. From a mixture of olive-oil soap, 36 lbs.; best tallow soap, 24 lbs. (both new and in shavings); water, 1 quart; melted in a covered bright copper pan, by the heat of a water bath, then coloured with vermilion (finely levigated), 2⁄2 oz.; and, after the mixture has cooled a little, scented with otto of roses, 3 oz.; essence of bergamot, 2⁄2 oz.; oil of cloves and cinnamon, of each 1 oz.

Soap, Rondeletia. This is merely cinnamon soap scented with the essence made with mixed essential oils, &c., known as rondeletia. It is coloured with brown or yellow ochre.

Soap, Sha′′ving. See Paste (Shaving).

Soap, Transpa′′rent. Prep. From perfectly dry almond, tallow, or soft soap, reduced to shavings, and dissolved, in a closed vessel or still, in an equal weight of rectified spirit, the clear portion, after a few hours’ repose, being poured into moulds or frames; after a few weeks’ exposure to a dry atmosphere, the pieces are ‘trimmed up’ and stamped, as desired. It may be scented and coloured, at will, by adding the ingredients to it while in the soft state. A rose colour is given by tincture of archil; and yellow, by tincture of turmeric or annotta. It does not lather well.

Soap, Windsor. Syn. Sapo Vindesoræ, S. Vindesoriensis, L. Prep. 1. (White; S. V. albus.) The best ‘English’ is made of a mixture of olive oil, 1 part, and ox tallow or suet, 9 parts, saponified by caustic soda. ‘French Windsor-soap’ is made of hogs’ lard, with the addition of a little palm oil. That of the shops is merely ordinary curd soap, scented with oil of caraway, supported with a little oil of bergamot, lavender, or origanum. To the finer qualities a little of the essences of musk and ambergris is occasionally added. 1⁄2 lb. of the mixed scents is the common proportion per cwt.

2. (Brown; S. V. fuscus.) This merely differs from the last in being coloured with burnt sugar, or (less frequently) with umber. Originally it was the white variety, that had become mellow and brown with age.

SO′DA. See Sodium.

SO′DIUM. Na. Syn. Natrium. The metallic base of soda. It was first obtained by Sir H. Davy, in 1807, by means of a powerful galvanic battery; but it may be more conveniently and cheaply procured, in quantity, by the method described under Potassium. The process, when well conducted, is, however, much easier and more certain than that for the last-named metal.

Prep. The anhydrous carbonate of sodium, 6 parts, is dissolved in a little water, and the solution mixed with charcoal in fine powder, 2 parts, and charcoal in small lumps, 1 part; the whole is then evaporated to dryness, transferred to an iron retort, and treated in the manner described at page 1353.

Obs. Very important improvements have been made in the manufacture of this metal by Deville, consisting partly in the simplification of the receiver, and partly in the addition of carbonate of calcium to the mixture, which addition appears to facilitate the reduction of the sodium in a most remarkable manner.

Prop., &c. Sodium is a soft silver-white metal, scarcely solid at common temperatures, fuses at 194° Fahr., and volatilises at a red heat; it oxidises very rapidly in the air; when placed on the surface of cold water, it decomposes that liquid with great violence, but generally without flame, in which it differs from potassium; on hot water it burns with a bright yellow flame—in both cases a solution of pure soda being formed. Sp. gr. ·972; it is more malleable than any other metal, and may be easily reduced into very thin leaves (Ure); its other properties resemble those of potassium, but are of a feebler character. With oxygen it forms two oxides; with chlorine, a chloride (common salt); and—with bromine, iodine, fluorine, &c., bromide, iodide, fluoride, &c., all of which may be obtained by similar processes to the respective compounds of potassium, which, for the most part they resemble.

Uses. Until recently sodium has been regarded as a mere mechanical or philosophical curiosity; it has now, however, become of great practical importance, from being employed in the manufacture of the metals aluminium, magnesium, &c.

Tests. Sodium salts are recognised by their solubility in water, and by their giving a precipitate with none of the ordinary reagents. They give a rich yellow colour to the colourless Bunsen or the pale blue blowpipe flame. They can, to a certain extent, be also distinguished from potassium salts by the carbonate being an easily crystallisable salt, effervescing in dry air; the carbonate of potassium being crystallised with difficulty, and deliquescent. Platinum chloride does not give a precipitate with sodium chloride; neither does picric acid, perchlorate of ammonium, nor tartaric acid.

Sodium, Acetate of. NaC2H3O2. Syn. Acetate of soda; Sodæ acetas (B. P., Ph. D.), L. Prepared from carbonate of sodium as the corresponding potassium salt; but the resulting solution is evaporated to a pellicle, and set aside to crystallise. Its crystals are striated oblique rhombic prisms; it effloresces slightly in the air, and is soluble in 4 parts of water at 60° Fahr. Diuretic.—Dose, 20 to 40 gr.

Sodium, Aluminate. This salt has of late been in extensive demand by the calico printer and dyer. In France it is obtained from banxite, a native hydrate of aluminate, by treatment with caustic or carbonate of soda. If caustic soda be employed, the powdered banxite is boiled with a solution of the alkali, whereas if carbonate of soda be used, it is fused with the banxite in a reverbatory furnace. By the first process the resulting aluminate of soda is dissolved in water, and evaporated to dryness, forms the commercial article. If prepared by ignition, the semifused mass is lixiviated with water, and then evaporated to dryness. Aluminate of soda prepared as above occurs as a white powder, of a greenish-yellow hue, and dry to the touch.

It is equally soluble in both hot and cold water, and readily decomposed by carbonic and acetic acids, bicarbonate and acetate of soda, chloride of ammonia, &c. Dr Wagner states that it is used for the preparation of lake colours, the induration of stone, in the manufacture of artificial stone, and for the saponification of fats in the manufacture of stearin candle manufacture, also in the preparation of an opaque, milky-looking glass, or semi-porcelain.

Aluminate of soda may likewise be procured from cryolite, as described under Alum.

Sodium Arseniates. Syn. Sodæ Arsenias (B. P.). Arsenious acid, 10 oz.; nitrate of soda, 8⁄2 oz.; dried carbonate of soda, 5⁄2 oz.; boiling distilled water, 35 fl. oz. Reduce the dry ingredients separately to fine powder, and mix them thoroughly in a porcelain mortar. Put the mixture into a large clay crucible and cover it with the lid. Expose it to a full red heat till all effervescence has ceased, and complete fusion has taken place. Pour out the fused salt on a clean flagstone, and as soon as it has solidified and while it is still warm put it into the boiling distilled water, stirring diligently. When the salt has dissolved filter the solution through paper, and set it aside to crystallise. Drain the crystals, and having dried them rapidly on filtering paper, enclose them in a stoppered bottle.

Sodium, Benzoate. Syn. Sodæ benzoas. (B. Cod.) Prep. Heat gently benzoic acid and water, and add caustic soda, q. s. to neutralise the acid. Filter, evaporate, and crystallise over sulphuric acid under a bell-glass.

Sodium, Bisulphate. Syn. Acid sulphate, Sodæ bisulphis. Prep. Dissolve crystallised carbonate of soda in twice its weight of water, and pass sulphurous acid in excess through the solution. Set it aside to crystallise. Its solution is used to preserve subjects.

Sodium, Bromide of. Syn. Sodii bromidum. Prepared as bromide of potassium.

Sodium, Carbonate of. Na2CO3. 10Aq. Syn. Carbonate of soda, Mono-carbonate of soda, Subcarbonate of s.†, Salt of barilla†; Sodæ carbonas (B. P., Ph. L., E., & D.), L. The carbonate of sodium of commerce (Washing soda) was formerly prepared from the ashes of seaweed, and other marine vegetables, in a somewhat similar manner to that by which carbonate of potassium is obtained; but it is now usually obtained from chloride of sodium by the action of heat, sulphuric acid, and carbonaceous matter.

Prep. 1. (From common salt or sulphate of sodium.) The latter is generally obtained by decomposing the former with sulphuric acid, the evolved gas being passed into water, or through flues filled with coke, over which a very small stream of cold water constantly flows, by which it is condensed, and forms ‘LIQUID HYDROCHLORIC ACID,’ a substance afterwards consumed, in large quantities, in the manufacture of chloride of lime, and for other purposes. The sulphate of sodium, obtained from this or any other source, is well mixed with an equal weight of chalk or limestone, and about half its weight of small coal, each being previously ground to powder, and the mixture is exposed to a strong heat in a ‘reverbatory furnace’ (see engr.) until the decomposition of the sulphate is complete, the mass during the calcination being frequently stirred about with a long iron rod; the semi-liquid is now raked into an iron trough, where it is allowed to cool, whilst the furnace is recharged with fresh materials. The crude dark-grey product, thus obtained, is known as ‘ball alkali,’ or ‘British barilla,’ and usually contains about 22 or 23% of pure hydrate of sodium. This is now lixiviated with tepid water, and the solution, after defecation, evaporated to dryness; the residuum is mixed with a certain quantity of sawdust, coal-dust, or charcoal, and roasted in a reverberatory furnace, at a heat not exceeding 700° Fahr., until all the sulphur is expelled. The product is the ‘soda-ash,’ ‘soda salt,’ or ‘British alkali,’ of commerce, and contains about 50% of pure sodium, partly in the state of carbonate, and partly as hydrate, the remainder being chiefly sulphate of sodium and common salt. When this is purified by solution in water, defecation, evaporation, and crystallisation, it furnishes commercial crystallised carbonate of soda. When this last is redissolved, and the filtered solution is carefully crystallised, it constitutes the ordinary carbonate of sodium used in pharmacy and medicine.

Another process for the preparation of commercial carbonate of sodium, known as the ‘ammonia process,’ has of late years met with considerable adoption. The history of this process, together with the process itself, are thus described by Dr R. Wagner: “Six years ago (he was writing in 1873), when the international jury at the Paris Exhibition expressed their opinion upon the state of the soda industry at that time, all the judges, whether practical or theoretical men, believed that Leblanc’s process (that previously described) would hold the field for a long time yet. This seemed still more probable, since a process had just been introduced for recovering the sulphur from the soda residues. At that time all the soda in use was prepared by this process, excepting a comparatively small amount obtained from Chili saltpetre and cryolite, although there were already tangible indications that soda could be made on a larger scale by another method, which would be cheaper than Leblanc’s process.

“The chemical section of the international jury at the Vienna Exposition, under the presidency of Professor A. W. Hofmann, constituted a congress of chemical technology. By its labours during the course of the summer this congress of scientific men was able to authenticate the very important fact that although Leblanc’s process might in the future possess some importance for certain branches of the industry, yet in most places another soda process would be introduced in the immediate future, and entirely supersede that of Leblanc. Since the time of the Paris Exhibition this new process has grown from a small germ to a strong tree.

“The process in question, and which is called by Professor Hofmann ‘the ammonia process,’ is not new, from either a chemical or scientific point of view. It belongs to the same methods as those in which oxide of lead, bicarbonate of magnesia, quicklime, alumina, silicate of alumina, oxide of chromium, or fluosilicic acid are employed to decompose chloride of sodium, and convert it directly into soda or its carbonate. None of these attempts met with a success deserving of notice; although for a century past efforts have been made to render them practically operative. The new process is founded upon a reaction noticed over thirty years ago—that of bicarbonate of ammonia upon a strong solution of common salt. The greater part of the sodium is precipitated as bicarbonate, while chloride of ammonium remains in solution, from which the ammonia for a second operation is expelled by quicklime. The carbonic acid necessary to convert the ammonia into bicarbonate of ammonia, and thus make the process a continuous one, is obtained by heating the bicarbonate of soda to convert it into the simple carbonate.

“The sensation which the ammonia process has created in industrial circles will render a brief history of its development not uninteresting.

“So far as I know, Harrison, Dyer, Grey, and Hemming were the first to patent the ammonia process in Great Britain in 1838. Great expectations were excited by it, but it soon sank into oblivion.

“Thirty or forty years ago the manufacture of soda was by no means at the head of the great branches of industry; at that time, too, ammonia was not to be had cheaply and in immense quantities, and that branch of machine building which has furnished the necessary apparatus for chemical industries did not exist. Besides this, Anton, of Prague, in 1840, claimed to have proved that in the ammonia process a very considerable portion of the common salt still remained undecomposed.

“After a sleep of sixteen years the ammonia process again entered the field. On the 26th of May, 1854, Turck took out a patent in France, and on the 21st June, the same year, Schlœsing, chemist of the Imperial Tobacco Factory at Paris, took out a patent for France and Great Britain. The mechanical portion and machinery for Schlœsing’s process were designed by Engineer E. Rolland, director of the tobacco factory. In 1855 a company was organised to work this process. An experimental manufactory was started at Puteaux, near Paris, but, owing to its situation and arrangements, as well as the salt monopoly, it could not produce soda cheap enough to compete with the other process, and hence, in 1858, the experiment was abandoned. Schlœsing and Rolland were of the opinion that sooner or later the new process must come into use in making soda.

“It must here be noticed that in 1858 Professor Heeren, of Hanover, subjected the ammonia process to a very careful test in his laboratory.

“From his experiments and calculations it was ascertained that this process was better adapted to the manufacture of the bicarbonate than of the simple protocarbonate of soda.

“To render this sketch more complete and historically true, it must be mentioned that T. Bell, of England, took out a patent, Oct. 13th, 1857, for a new soda process, which in principle and practice was almost literally the same as that of Dyer.

“It was known when the jury was working at Paris in 1867 that essential improvements had been introduced into the ammonia process by the efforts of Marguerite and De Sourdeval, of Paris, and James Young, of Glasgow. A more important fact, however, is that Solvay and Co., of Conillet, in Belgium, actually exhibited at the Paris Exhibition carbonate of soda prepared by this new process.

“Since that time the ammonia process has been developed and perfected to such an extent, especially by Solvay, Honigmann, and Prof. Gerstenhœfer, that as early as February, 1873, A. W. Hofmann, in his introduction to the third group of the catalogue of the Exhibition of the German Empire, was able to make this remark:—‘At all events the ammonia process is the only one which threatens to become an important competitor of the now also most exclusively employed process of Leblanc.’ The Vienna Exposition has since proved the truth of this assertion.

“There are now large works in England, Hungary, Switzerland, Westphalia, Thueringia, and Baden, which employ the improved ammonia process, and some of them make fifteen tons of soda per day.

“The advantages of the new process over that of Leblanc are very evident, although the details of the process have not yet been made public.

“The chief advantage consists in the direct conversion of salt into carbonate of soda, and next from the fact, that from a saturated brine only the sodium is precipitated, with none of the other metals of the mother liquor. Besides this, the product is absolutely free from all sulphur compounds, the soda is of a high grade, the apparatus and utensils are very simple, there is a great saving of labour and fuel, and no noxious gases and waste products are produced, which is of importance from a sanitary point of view. The only weak point of the ammonia process is the loss of chlorine, which is converted into worthless chloride of calcium.

“The effect which the general introduction of the new soda process will exert upon large chemical industries in general, and especially upon the consumption of sulphur, the manufacture of sulphuric acid, and chloride of lime, cannot be overlooked.”

3. Another method for the direct preparation of soda and potash from their chlorides is described in the ‘Bayerisches Industrie und Gewerbe Blatt.’ The process is thus described by its author, Herr E. Bohlig:

1. Magnesium oxalate (freshly prepared when newly starting, but, after the first operation, obtained as a dry product in the next step) is allowed to drain, and then mixed in a large vat with the proper quantities of sodium chloride, or concentrated brine and hydrochloric acid, after which it is allowed to stand a few hours. Decomposition takes place almost instantaneously; all the magnesium goes into solution in form of syrupy magnesium chloride, while all the sodium and oxalic acid are deposited as a crystalline acid salt (acid sodium oxalate, or binoxalate of sodium).

Since the magnesium oxalate is always obtained of the same composition and in the same quantity, it is sufficient to determine its weight once for all, and to take each time the previously common amounts of common salt. The acid need not be weighed either; it must be added in just sufficient quantity to destroy the milky appearance which the mixture first assumes.

The reaction is as follows:

MgC2O4 + HCl + NaCl = NaHC2O4 + MgCl2

Magnesium oxalate. + Hydrochloric acid. + Sodium chloride. = Sodium binoxalate. + Magnesium chloride.

The crystalline powder of sodium binoxalate is transferred to large draining filters, washed with water until the acid solution of magnesium chloride is removed, and worked up, as below described, while still moist.

The acid solution of magnesium chloride is made use of several times in succession as so much hydrochloric acid, together with a quantity of fresh acid sufficient for the reaction. Finally, when the magnesium chloride has inconveniently accumulated, it is worked up by itself into magnesia and hydrochloric acid.

2. In order to obtain the soda, the sodium binoxalate is brought together with an equivalent quantity of magnesium carbonate and water in a tight cask. As soon as the remaining air has been nearly expelled by the generated carbonic acid gas, the cask is closed, and a stirring mechanism set in motion.

A pressure gauge attached to the cask indicates a gradual rise of the pressure to two atmospheres, but, on continual stirring, this diminishes, until, finally, the gauge stands again at 0°. The cask now contains a concentrated solution of sodium bicarbonate, and a precipitate of magnesium oxalate, which latter, being coarsely granular, is easily separated from the liquid, and is used over again, after washing, for a new operation.

The solution of sodium bicarbonate is boiled for a short time with magnesia, obtained in distilling magnesium chloride, and both are thereby converted into simple carbonates. Both reactions are shown in the following scheme:

1. NaHC2O4 + MgCO3 = NaHCO3 + MgC2O4

Sodium binoxalate. + Magnesium carbonate. = Sodium bicarbonate. + Magnesium oxalate.

2. 2NaHCO3 + MgO = Na2CO3 + MgCO3 + H2O

Sodium bicarbonate. + Magnesia. = Sodium carbonate. + Magnesium carbonate. + Water

As the solution of sodium carbonate, after concentration to 40°B., is incapable of dissolving or retaining in solution any sodium oxalate, it follows that the whole of the oxalic acid is recovered. The magnesia which is required for the purpose is obtained by distilling magnesium chloride, which thereby splits up into hydrochloric acid and magnesia. One half of the latter receives, as we have seen, its carbonic acid by boiling with sodium bicarbonate; the other half is placed, whilst still moist, upon trays in great wooden closets, through which the gases of the furnace pass, and is thereby carbonated. The process may also be so modified that the sodium binoxalate is first decomposed by caustic magnesia, and that magnesium carbonate is afterwards added.

The whole mixture is then transferred to a stirring cask, provided with openings for the passage of cooled furnace gases, whereby the caustic soda present is very soon carbonated.

3. As soon as a large quantity of magnesium chloride solution has accumulated, it is tested as follows:—A small sample is mixed, while boiling, with magnesium oxalate, as long as the latter is dissolved, and then allowed to cool. There should be no crystalline deposit of sodium binoxalate formed, a proof that the solution does not contain any sodium chloride in excess, and is fit for distillation. It is first neutralised by adding some more magnesia, and evaporated over a naked fire in large kettles to a doughy consistence, short of driving off the hydrochloric acid. It is then transferred into the ordinary soda furnace, where it is distilled with a moderate fire. The eliminated hydrochloric acid is condensed in the usual manner.

The residuary mass should not be heated red hot, so as not to impair its porosity or its ready affinity for carbonic acid. If, however, the first-mentioned test shows the magnesium chloride to contain sodium chloride the whole mass must be mixed with magnesium oxalate, and after removal of the precipitated sodium oxalate, saturated with magnesia and distilled. The same process, in all its details, may also be employed for the manufacture of potassa and its carbonate.

4. Another method of manufacture of commercial soda is by treating the mineral cryolite (a double fluoride of sodium and aluminium) with either caustic, or hydrate of lime. The results of the reaction are caustic soda, sodium aluminate, and calcium fluoride.

The aluminate and caustic soda being both soluble in water, a stream of carbonic acid is passed through the solution containing them, whereby all the soda becomes converted into carbonate, whilst the alumina is thrown down as an insoluble precipitate. In the wet way, if enough hydrate of lime be employed, all the soda may be obtained in the caustic condition.

This process is largely used in Germany. Various other processes for the manufacture of commercial soda have been devised, some of which are still followed, whilst others, being impracticable, have collapsed.

Mr Kingzett, in his work on the alkali trade, has described most of them.

When anhydrous carbonate of sodium is required (Sodæ carbonas exsiccata, B. P., Ph. L.; Sodæ carbonas siccatum, Ph. E. & D.), the crystallised carbonate is heated to redness, and, when cold, powdered.

Prop., &c. Carbonate of sodium forms large, transparent, oblique rhombic prisms, which, as ordinarily met with, and of the formulæ Na2CO3.10Aq; but by particular management may be had with fifteen, nine, seven, or sometimes with only one molecule of water of crystallisation (Fownes); it is soluble in twice its weight of water at 60°, and less than an equal weight at 212° Fahr. As a medicine it is deobstruent and antacid, and is given in doses of 10 to 30 gr. It is also, occasionally, used to make effervescing draughts. When taken in an overdose it is poisonous. The antidotes are the same as for carbonate of potassium. The crude carbonate is largely employed in the manufacture of soap, glass, &c.

Fifty three gr. of the dried carbonate are equal to 143 of the crystallised salt. The medicinal properties of both are similar. It has, however, the disadvantage of being difficultly soluble in water.

The ordinary carbonate of sodium generally contains either sulphates or chlorides, or both; and these may be detected as under Carbonate of Potassium. “When supersaturated with nitric acid, it precipitates only slightly, or not at all, chloride of barium or nitrate of silver; and 143 gr. require at least 960 grain-measures of solution of oxalic acid” (B. P.). At a high temperature 100 gr. lose 62·5 gr. of water.

Sodium, Bicarbonate of. NaHCO3. Syn. Sesquicarbonate of soda, Sodæ bicarbonas (B. P., Ph. L., E., & D.). This salt can be prepared in exactly the same manner as the corresponding salt of potassium. Another method is as follows:—Take of crystallised carbonate of sodium, 1 part; dried carbonate of sodium, 2 parts (both in powder); triturate them well together, and surround them with an atmosphere of carbonic acid gas, under pressure; let the action go on until no more gas is absorbed, which will generally occupy 10 to 14 hours, according to the pressure employed, then remove the salt, and dry it at a heat not above 120° Fahr.

Prop., &c. A crystalline white powder; it is soluble in 10 parts of water at 60° Fahr., but it cannot be dissolved in even warm water without partial decomposition; it is more pleasant tasted and more feebly alkaline than the carbonate of the same base. When absolutely pure it does not darken turmeric paper, or only very slightly. The dose is from 10 to 40 gr., as an antacid and absorbent. It is much employed in the preparation of effervescing powders and draughts, for which purpose

20 gr. of commercial bicarbonate of sodium
\—————————\/——————————/
are taken with
/—————————/\———————-\
18 gr. of crystallised tartaric acid;

17 gr. of crystallised citric acid; or

⁄2 fl. oz. of lemon juice.

The quantity of bicarbonate any given sample contains may be approximately determined by well washing 100 gr. of the salt with an equal weight of water, and filtering the solution. The residuum left upon the filter, dried at a heat of 120° Fahr., and weighed, gives the per-centage of pure bicarbonate of sodium present (very nearly). The solution of this in water will give only a very trifling white precipitate with corrosive sublimate; whilst the filtered portion, which was used to wash the salt, will give a red one, if it contains the simple carbonate of sodium.

Sodium, Chloride of. NaCl. Syn. Sodii chloridum (B. P., Ph. L., & D.), Sodæ murias (Ph. E.), L. This important and wholesome compound appears to have been known in the earliest ages of which we have any record. It is mentioned by Moses (Gen. xix, 26), and by Homer in the Iliad (lib. ix, 214). In ancient Rome it was subjected to a duty (vectigal salinarium); and even at the present day a similar tax furnishes no inconsiderable portion of the revenue of certain nations. Common salt forms no small portion of the mineral wealth of England, and has become an important article of commerce in every part of the known world. The principal portion of the salt consumed in this country is procured by the evaporation of the water of brine springs. It is also prepared by the evaporation of sea-water (hence the term ‘sea-salt’), but this process has been almost abandoned in England, being more suited to hot dry climates or to very cold ones.

Var. Bay salt; SAL MARINUS, SAL NIGER; imported from France, Portugal, and Spain, and obtained from sea-water evaporated in shallow ponds by the sun; large-grained and dark-coloured.—British bay salt, Cheshire large-grained s.; by evaporating native brine at a heat of 130° to 140° Fahr.; hard cubical crystals. Both of the above are used to salt provisions for hot climates, as they dissolve very slowly in the brine as it grows weaker. Cheshire stoved salt, LUMP S., BASKET S.; obtained by evaporating the brine of salt springs; small flaky crystals.—London’s patent solid salt; Cheshire rock salt, melted and ladled into moulds.—Rock salt, FOSSIL S.; SAL GEMMÆ, SAL FOSSILIS; found in mineral beds in Cheshire; has commonly a reddish colour; chiefly exported for purification.

Prop. Pure chloride of sodium is fixed in the air; crystallises in anhydrous cubes, which are often grouped into pyramids or steps; dissolves in about 2⁄2 parts of water at 60° Fahr.; its solubility is not increased by heat; it is slightly soluble in proof spirit; insoluble in alcohol; decrepitates when heated; fuses at a red heat, and volatilises at a much higher temperature.

Pur., &c. The common salt of commerce contains small portions of chloride of magnesium, chloride of calcium, and sulphate of calcium; and hence has commonly a slightly bitter taste, and deliquesces in the air. To separate these, dissolve the salt in 4 times its weight of pure water, and drop into the filtered solution, first, chloride of barium, and then carbonate of sodium, as long as any precipitate falls; filter, and evaporate the clear fluid very slowly, until the last crystallises, which is pure chloride of sodium. (‘Thomson’s Chem.,’ ii, 377.) For medical purposes the Ph. E. orders the salt to be dissolved in boiling water, and the solution to be filtered and evaporated over the fire, skimming off the crystals as they form, which must then be quickly washed in cold water, and dried. A solution of pure salt is not precipitated by a solution of carbonate of ammonium, followed by a solution of phosphate of sodium; a solution of 9 gr. in distilled water is not entirely precipitated by a solution of 26 gr. of nitrate of silver. (Ph. E.)

Uses. Common salt is stimulant, antiseptic, and vermifuge, and is hence employed as a condiment, and for preserving animal and vegetable substances. It is also occasionally used in medicine, in clysters and lotions.

Sodium, Dried Sulphate of. Syn. Sodæ sulphas exsiccata, Effloresced Glauber salt. Expose the crystals to a warm dry air till they fall into powder. They lose half their weight. The dose is reduced in like proportion.

Sodium, Effervescing Citro-tartrate of. Syn. Sodæ citro-tartras effervescens. (B. P.) Prep. Mix thoroughly, powdered bicarbonate of soda, 17 oz.; tartaric acid, 8 oz.; and citric acid, 6 oz.; place in a dish or pan of suitable form, heated to between 200° and 220° Fahr., and when the particles begin to aggregate, stir assiduously till they assume a granular form. By means of suitable sieves separate the granules of uniform and most convenient size. Preserve in well-closed bottles.

Sodium, Ethylate. Prepared as Potassium ethylate, substituting sodium for potassium. Properties similar to ethylate of potassium.

Sodium, Hydrate of. NaHO. Syn. Hydrate of soda, Sodium hydrate, Caustic soda; Sodæ hydras. Prep. Exactly in the same manner from carbonate of sodium as potassium hydrate is prepared from carbonate of potassium.

The ‘Pharmaceutical Journal’ states that a pure hydrate of sodium is now manufactured from metallic sodium by the following method:—A deep silver vessel, of a hemispherical form, and capable of holding about four gallons of water, is employed. Into this vessel, which is cooled externally with a current of cold water, is placed a very little water, and upon the water is placed a cube of metallic sodium, of about half an inch in diameter.

The vessel is made to revolve, so as continually to bring fresh portions of liquid into contact with the metal, and by this means explosion is avoided. When the first cube of metal has dissolved, and yielded a thick syrupy liquid, a little more water and a second cube of metal are added, and the reaction allowed to take place, as before, the vessel being kept in motion all the time. In this manner several pounds of sodium may be worked up into soda.

The thick syrup so resulting is next evaporated down, heated to redness, fused, and poured into a mould.

Inasmuch as the price of sodium is five shillings a pound, the yield of soda from 1 lb. of metal being about 1⁄4 lb., it is plain that the alkali so prepared must be cheap.

The danger of explosions (which, however, are not likely to occur if proper care is taken) necessitates the employment of skilled labour in this manufacture, and constitutes a very serious drawback to the commercial success of the process.

Greyish, semitranslucent, deliquescent masses, very soluble in water, and bearing a very great resemblance to the corresponding potassium compound.

Sodium, Hypochlo′′rite of. Syn. Chlorinated soda, Chloride of soda‡; Soda chlorinata, L. Prep. (Dr Christison.) Dried carbonate of sodium, 19 parts, are triturated with water, 1 part, and the mixture placed in a proper vessel, and exposed to the prolonged action of chlorine gas, generated from a mixture of chloride of sodium, 10 parts; binoxide of manganese, 8 parts; sulphuric acid, 14 parts; (diluted with) water, 10 parts.

Sodium Hypophosphate. See Phosphorus.

Sodium, Hyposul′phite of. Na2S2O3. Syn. Sodæ hyposulphis, L. Prep. 1. Dried carbonate of sodium, 1 lb.; flower of sulphur, 10 oz.; mix, and slowly heat the powder in a porcelain dish until the sulphur melts; stir the fused mass freely to expose it to the atmosphere until the incandescence flags, then dissolve the mass in water, and immediately boil the filtered liquid with some flowers of sulphur; lastly, carefully concentrate the solution for crystals.

2. A stream of well-washed sulphurous anhydride gas is passed into a strong solution of carbonate of sodium, which is then digested with sulphur at a gentle heat during several days; by evaporating the solution at a moderate temperature, the salt is obtained in large and regular crystals.

3. (Capaun’s process.) Boil a dilute solution of caustic soda with sulphur to saturation, then pass sulphurous acid gas into the solution until a small portion, when filtered, is found to have a very pale yellow colour; when this is the case, it must be filtered and evaporated, as before.

4. (P. Cod.) Dissolve carbonate of sodium, 8 parts, in water, 16 parts; add of sublimed sulphur, 1 part, and pass sulphurous acid gas, in excess, into the solution; next boil the liquid in a glass matrass for a few minutes, filter, gently evaporate the filtrate to 1-3rd its volume, and set it aside in a cool place to crystallise.

Prop., &c. Hyposulphite of sodium crystallises in four-sided prisms, which, in the dry state, are unalterable in the air; it is freely soluble in water. It may be perfectly freed from sulphide of sodium by agitating it with about half its weight of alcohol; the alcohol dissolves out the sulphide, which may then be easily separated. This salt is now very extensively used in the practice of photography, also as an ‘antichlore,’ to extract the last traces from paper pulp.

Sodium, Iodide of. NaI. Syn. Sodii iodidum. Prep. As Iodide of Potassium. This, as well as the bromide, crystallises in clear or whitish cubes, deliquescent, and soluble in water. Used in medicine in the same manner as the corresponding potassium salts.

Sodium and Iron, Pyrophosphate of. Syn. Sodæ et ferri pyrophosphas, Natrum pyrophosphoricum ferratum. (Ph. G.) Prep. Dissolve 20 oz. of pyrophosphate of soda in 40 oz. of cold distilled water, and add, gradually, to the solution, and with constant stirring, 8 oz. (by weight) of solution of perchloride of iron (Ph. G.), previously diluted with 22 oz. of distilled water, as long as the precipitate is redissolved. Filter, and to the clear, bright green liquid thus obtained pour in 100 oz. (by weight) of rectified spirit, wash the precipitate with more spirit, press it between blotting paper, and dry by a gentle heat.

Sodium Lactate. Syn. Sodii lactas. Prep. Let lactate acid be diluted with three parts of water; saturate whilst boiling with sodium bicarbonate; then evaporate, and run into flakes.

Sodium lactate is a very deliquescent salt. The solution evaporated to the consistence of a syrup deposits flattened prismatic crystals, and stellar groups of needles.

Sodium, Ni′trate of. NaNO3. Syn. Chili saltpetre, Cubic nitre; Sodæ nitras, L. This salt occurs native like ordinary nitre, and is chiefly imported into England from South America. It is largely employed as a manure, in the preparation of nitric acid, and, recently, in the manufacture of fireworks, on account of the comparative slowness with which it burns. It is deliquescent and very soluble in water.

Sodium, Nitrite of. Syn. Sodæ nitris. (B. P., 1864.) Mix nitrate of soda, 1 lb., and charcoal, recently burned, and in fine powder, 1⁄4 oz., thoroughly in a mortar, and drop the mixture in successive portions into a clay crucible, heated to a dull redness. When the salt has become quite white, raise the heat so as to liquefy it, pour on to a clean flagstone, and when it has solidified break into fragments, and keep in a stoppered bottle.

Sodium, Oxide of. Na2O. Syn. Anhydrous soda. Prep. By burning dry metallic sodium in air. White powder, very deliquescent, and soluble in water, forming pure sodium hydrate.

Sodium, Phos′phate of. Na2PO4.12Aq. Syn. Common tribasic phosphate of soda, Rhombic p. of s.; Sodæ phosphas (B. P., Ph. L., E., & D.). Prep. 1. (Ph. E.) Take of powdered bone ashes, 10 lbs.; sulphuric acid, 44 fl. oz.; mix, add gradually of water 6 pints, and digest for 3 days, replacing the water which evaporates; then add 6 pints of boiling water, strain through linen, and wash the residue on the filter with boiling water; mix the liquors, and, after defecation, decant and evaporate to 6 pints; let the impurities again settle, and neutralise the clear fluid, heated to boiling, with a solution of carbonate of sodium in slight excess; crystals will be deposited as the solution cools, and by successively evaporating, adding a little more carbonate of sodium to the mother liquor till it is feebly alkaline, and cooling, more crystals may be obtained; these must be kept in close vessels. The formula of the Ph. D. is nearly similar. It is placed in the Materia Medica of the B. P. and Ph. L.

2. (Funcke.) To ground calcined bones, diffused through water, add a little dilute sulphuric acid to saturate any carbonate of calcium present; when effervescence ceases, dissolve the whole in nitric acid, q. s.; to this solution add as much sulphate of sodium as the bone ash used, and distil the whole to recover the nitric acid; the residuum is treated with water, and the resulting solution filtered, evaporated, and crystallised.

Prop., &c. It forms very beautiful oblique rhombic prisms, of the formula Na2H,PO4,12H2O, which effloresce in the air, dissolve in about 4 parts of cold water and in 2 parts at 212° Fahr., and fuse when heated. As a medicine it is mildly aperient, in doses of ⁄2 to 1 oz., or even more; and antacid in doses of 20 to 30 gr., frequently repeated. It has a purely saline taste, resembling that of culinary salt, and is commonly taken in broth or soup.

Sodium Pyrophosphate (Crystallised). Syn. Sodæ pyrophosphas crystallisata. (P. Cod.) Prep. This salt may be obtained by heating, gently at first, and afterwards to a red heat, crystallised phosphate of sodium in a platinum crucible until all the water is driven off, and the salt has become fused. Dissolve the fused mass in water, filter, and concentrate until it has a density of 1·20, and crystallise in the cold.

Sodium, Salicylate of. Syn. Sodæ salicylus. Prep. Made by neutralising a solution of pure salicylic acid with caustic soda, and evaporating to dryness. It must be purified by crystallisation from alcohol. Antipyretic; given in acute rheumatism.—Dose, 10 to 20 grams.

Sodium Santonate. Syn. Sodæ santonas. This salt is made by digesting an alcoholic solution of santonic acid with carbonate of soda, evaporating, redissolving in strong alcohol, and crystallising.

Sodium, Sesquicarbonate of. Na4H2(CO3)3. A salt found native on the banks of the soda lakes of Sotrena, in Africa, whence it is exported as ‘Trona.’

Sodium Silicate. See Glass, Soluble.

Sodium, Stan′nate of. Na2SnO3. Prep. (Greenwood & Co.) Caustic soda, 22 lbs., is heated to low redness in an iron crucible, when nitrate of sodium, 8 lbs., and common salt, 4 lbs., are added; when the mixture is at a ‘fluxing heat,’ 10 lbs. of feathered block tin is stirred in with an iron rod, both the stirring and heat being continued until the mass becomes red hot and ‘pasty,’ and ammoniacal fumes are given off. The product may be purified by solution and crystallisation. Patented. (See below.)

Sodium, Stan′nite of. Prep. (Greenwood & Co.) From caustic soda, 13⁄2 lbs.; feathered block tin and common salt, of each 4 lbs.; as the last. Patented. Both the above are used to prepare tin mordants (about 12 oz. to water, 1 gall.). The stannate and stannite of potassium are prepared in a similar manner.

Sodium Sulphate. Syn. Sodæ sulphis. Prep. Pass sulphurous acid to saturation through a solution of carbonate of soda. Used internally for sarcina ventriculi, and externally as an application in skin diseases of fungous origin. Hyposulphate of soda is employed in the same cases.

Sodium, Sul′phate of. Na2SO4.10Aq. Syn. Glauber’s salt; Sodæ sulphas (B. P., Ph. L., E., & D.), Sal catharticus Glauberi†, L. This is obtained as a secondary product in various chemical processes; but it may be easily formed directly from its constituents.

Prop., &c. It forms transparent, six-sided, irregular, channelled prisms, with dihedral summits, of the formulae Na2SO410H2O, which effloresce in the air, and fall to an opaque white powder; soluble in about 3 parts of water at 60°, and in considerably less at 100° Fahr., but at a higher temperature its solubility rapidly lessens; insoluble in alcohol; fuses when heated. It is seldom wilfully adulterated. When pure the solution is neutral to test paper; nitrate of silver throws down scarcely anything from a dilute solution; nitrate of baryta more, which is not dissolved by nitric acid. It loses 55·5% of its weight by a strong heat.

Uses. It is purgative, but being extremely bitter-tasted, is now less frequently used than formerly. Its nauseous flavour is said to be covered by lemon juice.—Dose, ⁄2 to 1 oz. The dried salts (SODÆ SULPHAS EXSICCATA) is twice as strong. Lymington Glauber’s salt is a mixture of the sulphates of soda and potassa obtained from the mother liquor of sea salt.

Sodium, Sul′phide of. Prep. (P. Cod.) Saturate a solution of caustic soda (sp. gr. 1·200) with sulphuretted hydrogen, closely cover up the vessel, and set it aside that crystals may form; drain, press them in bibulous paper, and at once preserve them in a well-closed bottle. Used to make mineral waters, and in certain skin diseases.

Of this salt Dr Ringer says—“it possesses the property of preventing and arresting suppuration, and stopping the formation of pus. Given for boils and carbuncles; it also produces excellent results.—Dose. For adults, ⁄10th of a grain, mixed with sugar of milk every hour or two on the tongue.

The anhydrous sulphides resemble closely and are prepared in the same manner as the potassium sulphides.

Sodium, Sulpho-Carbolate. Syn. Sodæ sulpho-carbolas. (Pareira.) Prep. Mix two volumes of pure carbolic acid with one volume of sulphuric acid in a flask, and heat the mixture to 280° or 290° F. for five minutes. Let cool, dilute, and saturate with carbonate of soda, evaporate, and crystallise. The other sulpho-carbolates may be prepared in the same manner.—Dose, 10 to 30 gr., in phthisis and zymotic diseases; externally, as a lotion in ozæna and fetid ulcers.

Sodium, Sulpho-Salicylate of. Syn. Sodæ sulpho-salicylas. Mr J. Williams obtains this salt by treating very pure salicylic acid with about twice its weight of sulphuric acid, then adding carbonate of barium, and decomposing the sulpho-salicylate of barium by sulphate of soda (see ‘Pharm. Journ.,’ Sept. 30th, 1876).

Sodium Sulphovinate. Syn. Sodii sulphovinas. Prep. Sulphovinic acid is first prepared by pouring gradually, with great care, and increasingly stirring with a glass rod, 1000 grams of 60° sulphuric acid into 1000 grams of rectified 96° alcohol. The mixture is left for some hours in contact, then diluted with 4 litres of distilled water, and afterwards saturated with pure barium carbonate.

When the saturation is complete the barium sulphate is allowed to deposit on a filter. The solution of barium sulphovinate is then decomposed with pure carbonate of soda until it ceases to give a precipitate.

The liquid, evaporated in a water bath, is left to crystallise. If necessary the crystals are purified by recrystallisation. They should be kept in well-closed flasks.

Sodium sulphovinate crystallises in hexagonal tables, which are slightly unctuous to the touch, and very soluble in water and in alcohol. If heated in a capsule they give off, at 120°, the alcohol which they contain in combination. They become gradually deprived of bitterness. Sodium sulphovinate ought not to contain sulphuric acid, nor have an acid taste. It should not be precipitated by barium chloride, and especially by soluble sulphates. The possession of either of these properties is a proof of faulty preparation, and that a portion of the sulphovinic acid has been decomposed. In such a case it should be rejected.

Sulphovinate of soda is said to be a very effective, and by no means unpleasant, saline aperient, and to be unattended with subsequent constipation. The dose is from 5 to 6 dr.

Sodium, Tartrate of, and Potassium. KNaC4H4O6.4Aq. Syn. Tartrate of potassa and soda, Rochelle salt, Seignette’s s., Tartarised soda†; Sodæ tartarata (B. P.), Sodæ, potassio-tartras (Ph. L.), Sodæ et potassæ tartras (Ph. E. & D.), Soda tartarizata,†, L. Prep. (Ph. L. 1836.) Take of carbonate of sodium, 12 oz.; boiling water, 2 quarts; dissolve, and add, gradually, of powdered bitartrate of potassium, 16 oz. (or q. s.); strain, evaporate to a pellicle, and set it aside to crystallise; dry the resulting crystals, and evaporate the mother liquor that it may yield more of them. The formulæ of the other colleges are nearly similar.

Prop., &c. Large, transparent, hard, right rhombic prisms, often occurring in halves; slightly efflorescent; soluble in 5 parts of water at 60° Fahr. Its “solution neither changes the colour of litmus nor of turmeric. On the addition of sulphuric acid, bitartrate of potassium is thrown down; on adding either nitrate of silver or chloride of barium nothing is thrown down, or only what is redissolved by the addition of water.” (Ph. L.) By heat it yields a mixture of the pure carbonates of potassium and sodium.

Potassio-tartrate of sodium is a mild and cooling laxative.—Dose, ⁄4 to 1 oz., largely diluted with water. It forms the basis of the popular aperient called SEIDLITZ POWDERS.

Sodium, Vale′′rianate of. NaC5H6O2. Syn. Sodæ valerianas (Ph. D.), L. Prep.(Ph. D.) Dilute oil of vitriol, 6⁄2 fl. oz., with water, ⁄2 pint; then dissolve of powdered bichromate of potassium, 9 oz., with the aid of heat, in water, 3⁄3 pints; when both solutions have cooled, put them into a matrass, and having added of fusel oil (alcohol amylicum—Ph. D.) 4 fl. oz., shake them together repeatedly until the temperature, which first rises to 150°, has fallen to 80° or 90° Fahr.; a condenser being connected, next apply heat so as to distil over about 4 pints of liquid; saturate this exactly with a pint, or q. s., of solution of caustic soda, separate the liquid from the oil which floats upon the surface, and evaporate it until the residual salt is partially liquefied; the heat being now withdrawn, and the salt concreted, this last, whilst still warm, is to be divided into fragments, and preserved in well-stopped bottles.

Obs. This salt is intended to be used in the preparation of the VALERIANATES OF IRON, QUININE, and ZINC.

SOILS. These are classified by agriculturists according to their chief ingredients, as loamy, clayey, sandy, chalky, and peaty soils. Of these the first is the best for most purposes, but the others may be improved by the addition of the mineral constituents of which they are deficient. Sand and lime or chalk are the proper additions to clayey soils, and clay gypsum, or loam, to sandy and gravelly ones. Clayey soils are expensive to bring into a fertile state; but when this is once effected, and they are well manured, they yield immense crops of wheat, oats, beans, clover, and most fruits and flowers of the rosaceous kinds.

The fertilisation of soils is suggested partly by chemical analysis, practical experience, and geological observations. In cases where a barren soil is examined with a view to its improvement it is, when possible, compared with an extremely fertile soil in the same neighbourhood, and in a similar situation; the difference given by their analyses indicates the nature of the manure required, and the most judicious methods of cultivation; and thus a plan of improvement is suggested, founded upon scientific principles.

The analysis of soils may be briefly and generally described as follows:—

1. The general character of the soil, as loamy, sandy, stony, rather stony, &c., being noted, 3 or 4 lbs. of it, fairly selected as an average specimen, may be taken during a period of ordinary dry weather. From this, after crushing or bruising the lumps with a piece of wood, all stones of a larger size than that of a filbert may be picked out, and their proportion to the whole quantity duly registered.

2. 1000 grains of the remainder may be next dried by the heat of boiling water, until the mass ceases to lose weight; and, afterwards, exposed to a moist atmosphere for some time. The loss of weight in the first case, and the increase of weight in the second, indicate the absorbent powers of the soil.

3. The matter from No. 2, freed from siliceous stones by garbling, may be gradually heated to dull redness in a shallow open vessel, avoiding waste from decrepitation, &c. The loss of weight, divided by 10, gives the percentage quantity of vegetable or organic matter present (nearly).

4. Another 1000 grains (see No. 1) may be next washed with successive portions of cold water as long as anything is removed. The residuum, after being dried, indicates the proportion of sand and gravel (nearly).

5. Another portion of the soil (100, 200, or more gr., according to its character) is tested in the manner described under Carbonate and Alkalimetry. The loss of weight in carbonic acid indicates the quantity of Carbonate of lime present in the sample examined; 22 gr. of the former being equal to 50 gr. of the latter.

6. Another like portion of the soil may be gently boiled for 4 or 5 hours, along with dilute hydrochloric acid, in a flask furnished with a long glass tube passing through the cork, to prevent loss (see ETHER); after that time the whole must be thrown upon a filter, and what refuses to pass through (silica) washed with distilled water, dried, ignited, and weighed.

7. The filtrate and washings from No. 6 are next successively treated for alumina (pure clay), lime, phosphate of lime, phosphoric acid, oxide of iron, alkalies (potassa or soda), ammonia (both ready formed and latent), &c. &c., in the manner noticed under Glass, Guano, and the names of the respective substances referred to. See Agriculture, Manures, &c.

SOL′ANINE. Syn. Solani, Solanina, L. A peculiar basic substance, obtained from the leaves and stem of Solanum Dulcamara or bitter-sweet, and other species of the Solanaceæ.

SOL′DERING. The union of metallic surfaces by means of a more fusible metal fluxed between them. The method of autogenous soldering, invented by M. De. Richmont, is an exception to this definition. In all the cases surfaces must be perfectly clean, and in absolute contact, and the air must be excluded, to prevent oxidation. For this last purpose the brazier and silversmith use powdered borax made into a paste with water; the coppersmith, powdered sal ammoniac; and the tinman, powdered resin. Tin-foil applied between the joints of fine brass work, first wetted with a strong solution of sal ammoniac, makes an excellent juncture, care being taken to avoid too much heat. See Solution (Soldering), and below.

SOL′DERS. Prep. 1. (For copper, iron, and dark brass.) From copper and zinc, equal parts; melted together. For pale brass more zinc must be used.

2. (Fine solder.) From tin, 2 parts; lead, 1 part. Melts at 350° Fahr. Used to tin and solder copper, tin plates, &c.

3. (For German silver.) From German silver, 5 parts; zinc, 4 parts; melted together, run into thin flakes, and then powdered. Also as No. 7.

4. (Glazier’s.) From lead, 3 parts; tin, 1 part. Melts at 500° Fahr.

5. (For gold.) Gold, 12 pennyweights; copper, 4 do.; silver, 2 do.

6. (For lead and zinc.) From lead, 2 parts; tin, 1 part.

7. (For pewter, Britannia metal, &c.) From tin, 10 parts; lead, 5 parts; bismuth, 1 to 3 parts.

8. (For silver.) From fine brass, 6 parts; silver, 5 parts; zinc, 2 parts.

9. (For tin plate.) From tin, 2 parts; lead, 1 part. The addition of bismuth, 1 part, renders it fit for pewter.

SOLE. The Solea vulgaris, a well-known fish. It is perhaps more frequently eaten than any other flat fish, and, when skilfully cooked, exceeds them all in delicacy, nutritiousness, and flavour.

SOLU′TION. Syn. Solutio, L. Under the head of solutions (SOLUTIONES), in pharmacy, are properly included only those liquids which consist of water, or an aqueous menstruum, in which has been dissolved an appropriate quantity of any soluble substance to impart to the liquor its peculiar properties. When spirit is the menstruum, the liquid receives the name of alcoholic solution, spirit, or tincture. In the B. P. and the Ph. L. & D. aqueous solutions are named LIQUORS (LIQUORES), whilst in the Ph. E., and in the old pharmacopœias generally, they are termed WATERS (AQUÆ).

The following list embraces all the solutions of the British pharmacopœias, with a few others likely to be useful to the reader. Some other preparations to which the name has been given will be found under Liquors, Tinctures, &c.

Solution of Ac′etate of Ammo′′nia. Syn. Liquor of acetate of ammonia, Water of a. of a., Mindererus’ spirit; Ammoniæ acetatis liquor (B. P.), Liquor ammoniæ acetatis (Ph. L. & D.), Ammoniæ acetatis aqua (Ph. E.), L. Prep. 1. (Ph. L.) From dilute acetic acid, 1 pint; exactly neutralised by sesquicarbonate of ammonia (in coarse powder), 9 dr., or q. s. Sp. gr. 1·022.

2. (Ph. E.) Distilled vinegar (preferably from French vinegar), sp. gr, 1·005, 24 fl. oz.; carbonate (sesquicarbonate) of ammonia, 1 oz., or q. s. Sp. gr. 1·011.

3. (Ph. D.) Sesquicarbonate of ammonia, 2⁄2 oz.; dilute acetic acid, 3 pints. Sp. gr. 1·012.

4. (B. P.) Carbonate of ammonia, 3⁄4, or sufficient; acetic acid (28 per cent.), 10; distilled water, 50. Dissolve the carbonate in the acid, and add the water.

Prop., &c. Free from colour and odour. It changes the colour neither of litmus nor turmeric. Sulphuretted hydrogen being dropped in, it is not discoloured, neither is anything thrown down on the addition of chloride of barium. What is precipitated by nitrate of silver is soluble in water, but especially so in nitric acid. Potassa being added, it emits ammonia; and sulphuric acid being added, it gives off acetic vapours. The fluid being evaporated, what remains is completely destroyed by heat.

Uses, &c. Solution of acetate of ammonia is a very common and excellent febrifuge and diaphoretic, and, in large doses, aperient saline liquor. Taken warm, in bed, it generally proves a powerful sudorific; and as it operates without heat, it is much used in febrile and inflammatory disorders. Its action may likewise be determined to the kidneys, by walking about in the cold air.—Dose, 2 to 6 dr., twice or thrice daily, either by itself or along with other medicines. Externally, as a discutient and refrigerant lotion; and diluted (1 oz. to 9 oz. of water), as a collyrium in chronic ophthalmia. For this last purpose it must be free from excess of ammonia.

5. (Concentrated.) Saturate acetic acid, sp. gr. 1·038, ⁄2 gall., with carbonate of ammonia (in powder), 2⁄2 lbs., or q. s.; carefully avoiding excess.

Obs. This article is in great demand in the wholesale drug trade, under the name of ‘concentrated liquor of acetate of ammonia’ (LIQ. AMMON. ACET. CONC.). It is very convenient for dispensing. One fl. dr. added to 7 fl. dr. of water forms the LIQUOR AMMONIÆ ACETATIS of the Ph. L.

Solution of Acetate of Lead. See Solution of Diacetate of Lead.

Solution of Acetate of Morphia. Syn. Liquor morphiæ acetatis (B. P., Ph. L., & D.), L. Prep. 1. (Ph. L.) Acetate of morphia, 4 dr.; acetic acid, 15 drops; distilled water, 1 pint; proof spirit, ⁄2 pint; mix, and dissolve. Sixty drops (minims) contain 1 gr. of acetate of morphia.—Dose, 5 to 15 or 20 drops.

2. (B. P.) Acetate of morphia, 4 gr.; diluted acetic acid, 8 minims; rectified spirit, 2 dr.; distilled water, 6 dr.; dissolve in the mixed liquids.—Dose, 10 to 60 minims.

3. (Ph. D.) Acetate of morphia, 82 gr.; rectified spirit, 5 fl. oz.; distilled water, 15 fl. oz. 120 drops (minims) contain 1 gr. of the acetate.—Dose, 10 to 45 or 50 drops, or similar to that of tincture of opium.

4. (Magendie.) Each fl. dr. contains 1⁄2 gr. of acetate (nearly).—Dose, 5 to 15 drops. Anodyne, hypnotic, and narcotic; in those cases in which opium is inadmissible. See Morphia.

Solution of Aconitia. Syn. Solutio Aconitiæ (Dr Turnbull). Prep. Aconitia, 1 gr.; rectified spirit, 1 dr. To be applied externally by means of a sponge in neuralgic and rheumatic affections.

Solution of Al′um (Compound). Syn. Bate’s alum water; Liquor aluminis compositus (Ph. L.), Aqua aluminosa composita †, L. Prep. (Ph. L.) Alum and sulphate of zinc, of each 1 oz.; boiling water, 3 pints; dissolve, and filter (if necessary). Detergent and astringent. Used as a lotion for old ulcers, chilblains, excoriations, &c.; and, largely diluted with water, as an eye-wash and injection.

Solution of Ammo′′nia. See Liquor of Ammonia.

Solution of Ammo′′nio-ni′trate of Sil′ver. Syn. Hume’s test; Solutio argenti ammoniati (Ph. E.), L. Prep. (Ph. E.) Nitrate of silver (pure crystallised), 44 gr.; distilled water, 1 fl. oz.; dissolve and add ammonia water, gradually, until the precipitate, at first thrown down, is very nearly, but not entirely, redissolved. Used as a test for arsenic.

Solution of Ammo′′nio-sul′phate of Cop′per. Syn. Liquor cupri ammonio-sulphatis (Ph. L.), Cupri ammoniati solutio (Ph. E.), C. a. aqua, L. Prep. (Ph. L.) Ammonio-sulphate of copper, 1 dr.; water, 1 pint; dissolve, and filter. Stimulant and detergent. Applied to indolent ulcers, and, when largely diluted, to remove specks on the cornea; also used as a test for arsenic.

Solution for Anatom′ical Preparations, &c. Syn. Antiseptic solution. Prep. 1. Nearly saturate water with sulphurous acid, and add a little creasote.

2. Dissolve chloride of tin, 4 parts, in water, 100 parts, to which 3% of hydrochloric acid has been added.

3. Dissolve corrosive sublimate, 1 part, and chloride of sodium, 3 parts, in water, 100 parts, to which 2% of hydrochloric acid has been added.

4. Mix liquor of ammonia (strong) with 3 times its weight (each) of water and rectified spirit.

5. Sal ammoniac, 1 part; water, 10 or 11 parts. For muscular parts of animals.

6. Sulphate of zinc, 1 part; water, 15 to 25 parts. For muscles, integuments, and cerebral masses.

7. (Dr Babington.) Wood naphtha, 1 part; water, 7 parts; or wood naphtha undiluted, as an injection.

8. (Sir W. Burnett.) Concentrated solution of chloride of zinc, 1 lb.; water, 1 gall. The substances are immersed in the solution for 2 to 4 days, and then dried in the air.

9. (Gannal.) Alum and culinary salt, of each ⁄2 lb.; nitre, ⁄4 lb.; water, 1 gall.

10. (Goadsby.)—a. From bay salt, 2 oz.; alum, 1 oz.; bichloride of mercury, 1 gr.; water, 1 pint. For ordinary purposes.

b. To the last add of bichloride of mercury, 1 gr.; water, 1 pint. For very tender tissues, and where there is a tendency to mouldiness.

c. From bay salt, ⁄4 lb.; bichloride of mercury, 1 gr.; water, 1 pint. For subjects containing carbonate of lime.

d. From bay salt, ⁄4 lb.; arsenious acid, 10 gr.; water, 1 pint; dissolve by heat. For old preparations.

e. To the last add of bichloride of mercury, 1 gr. As the last, when there is a tendency to the softening of parts; and, diluted, for mollusca. These solutions are approved of by Prof. Owen.

11. (M. Réboulet.) Nitre, 1 part; alum, 2 parts; chloride of lime, 4 parts; water, 16 or 20 parts; to be afterwards diluted according to circumstances. For pathological specimens. 12. (Dr Stapleton.) Alum, 2⁄4 oz.; nitre, 1 dr.; water, 1 quart. For pathological specimens.

13. (For Feathers—Beasley.) Strychnia, 16 gr.; rectified spirit, 1 pint.

Obs. These fluids are used for preserving ANATOMICAL PREPARATIONS, OBJECTS OF NATURAL HISTORY, &c., by immersing them therein, in close vessels; or, for temporary purposes, applying them by means of a brush or piece of rag. The presence of corrosive sublimate is apt to render animal substances very hard. See Putrefaction.

Solution, Antiseptic. (See above.)

Solution of Arseniate of Ammonia. Syn. Liquor arseniatis ammoniæ. (Hosp. Of St Louis.) Prep. Arseniate of ammonia, 4 gr.; distilled water, 4 oz.; spirit of angelica, 2 dr.—Dose, 12 to 30 minims. There are other formulæ for the solution, differing in strength from the above.

Dr Neligan gives us Biett’s:—Arseniate of ammonia, 1⁄2 gr.; distilled water, 3 oz.; spirit of angelica, 6 dr.—Dose, 1 to 3 dr.

Bouchardat says 6 gr. to 8 oz. of distilled water.—Dose. From 12 drops to 1 dr.

Solution of Arseniate of Soda. Syn. Liquor arseniatis sodæ. Pearson’s Arsenical solution. Prep. Arseniate of soda, 4 gr.; distilled water, 4 oz.—Dose, 12 minims to 30.

Solution of Arseniate of Soda. (B. P.) Syn. Liquor sodæ arseniatis. Prep. Dissolve arseniate of soda (rendered anhydrous by a heat not exceeding 300° Fahr.) 4 gr. in distilled water, 1 oz.—Dose, 5 to 10 minims.

Solution, Arsenical. Syn. Mineral solution; Solutio arsenicalis, Solutio mineralis, L. Prep. 1. (Devergie.) As SOLUTION OF ARSENITE OF POTASSA, Ph. L., but of only 1-50th the strength, and flavoured with compound spirit of balm, and coloured to a deep rose with cochineal.

2. (Pearson.) Arseniate of soda, 4 gr.; water, 4 fl. oz.; dissolve.—Dose, 10 to 30 drops during the day. (See below.)

Solution of Arse′′nious Acid. See Drops, Ague, and Arsenious acid.

Solution of Ar′senite of Potas′sa. Syn. Fowler’s mineral solution; Liquor potassæ arsenitis. (Ph. L.), Liquor arsenicalis (B. P., Ph. E., D., & U. S.), L. Prep. (B. P., Ph. L., & E.) Arsenious acid, coarsely powdered, and carbonate of potassa, of each 80 gr.; distilled water, 1 pint; boil until dissolved, and add, to the cold solution, compound tincture of lavender, 5 fl. dr.; water, q. s. to make the whole exactly measure a pint. Tonic, antiperiodic, and alterative.—Dose, 4 or 5 drops, gradually and cautiously increased; in agues and various scaly skin diseases. It is preferably taken soon after a meal. See Arsenious acid, &c.

Solution of Atropia. Syn. Liquor atropiæ (B. P.). Prep. Atropia, 4 gr.: rectified spirit, 1 dr.; dissolve, and add water, 7 dr.; mix.—Dose, 1 minim.

Solution of Auro-Chloride of Gold. Syn. Solutio auri ammonio-chloridi. (Furnari.) Prep. Ammonio-chloride of gold, 8 gr.; distilled water and rectified spirit, of each 10 oz.—Dose. A teaspoonful morning and evening in sugared water for dysmenorrhœa and amenorrhœa.

Solution of Bimeconate of Morphiæ. Solutio morphiæ bimeconatis. There is no standard formula for this preparation. It is made about the same strength as tincture of opium. The following contains 1 gr. in 84 minims:—Bimeconate of morphia, 10 gr.; rectified spirit, 1 dr.; distilled water, 13 dr.

Solution of Bismuth and Citrate of Ammonia. Syn. Liquor bismuthi et ammoniæ citratis (B. P.). Purified bismuth, 1; nitric acid, 2; citric acid, 2; solution of ammonia, a sufficiency; mix the nitric acid with an ounce of distilled water, and add the bismuth in successive portions. When effervescence has ceased, apply for ten minutes a heat approaching that of ebullition, and decant the solution from any insoluble matter. Evaporate the solution until it is reduced to 2, then add the citric acid previously dissolved in 4 of distilled water, and afterwards the solution of ammonia in small quantities at a time, until the precipitate formed is redissolved, and the solution is neutral or slightly alkaline to test paper; dilute with distilled water to the volume of 20.—Dose, ⁄2 to 1 dr.

Solution of Bromine. Syn. Liquor brominii. (Pourche.) Prep. Bromine, 1 part; distilled water, 40 parts.—Dose, 5 or 6 drops, 3 times a day. A stronger solution (1 part to 10) is sometimes used externally.

Solution of Carbon (Detergent). Syn. Liquor carbonis detergens. This name is applied to an alcoholic solution of coal tar. Properly diluted it is used externally in skin diseases.

Solution, Brandish’s. See Solution of Potassa.

Solution, Burnett’s. A solution of chloride of zinc. See Solution for Anatomical preparations (above), also Disinfecting compounds.

Solution of Camphor, Carbonated. Syn. Solutio camphoræ carbonica. (Swediaur.) Prep. Water saturated with carbonic acid gas, 2 lbs.; powdered camphor, 3 dr.

Solution of Camphor and Chloroform. Syn. Solutio camphoræ et chloroformi. (Messrs Smith.) Prep. Camphor, 3 dr.; chloroform, 1 fl. dr. Dissolve. For exhibiting camphor with yolk of egg in emulsions.

Solution of Carbolic Acid. For the Toilette. Prep. Crystallised carbolic acid, 10 parts; essence of millefleur, 1 part; tincture of Quillai Saponaria, 50; water, 1000 parts. Mix. The saponine replaces soap with advantage. The above should be employed diluted with 10 times its bulk of water, for disinfecting the skin, for washing the hands, after any risk of contagion, inoculation, &c.

Solution of Car′bonate of Ammo′′nia. Syn. Solution of sesquicarbonate of ammonia, Carbonate of ammonia water; Liquor ammoniæ sesquicarbonatis (Ph. L.), Aqua ammoniæ carbonatis (Ph. E.). Prep. (Ph. L. & E.) Sesquicarbonate of ammonia, 4 oz.; distilled water, 1 pint; dissolve. Stimulant and antacid.—Dose, ⁄2 to 1 fl. dr., in water.

Solution of Carbonate of Magnesia. Syn. Liquor magnesiæ carbonatis (B. P.) Prep. Dissolve separately, each in ⁄2 a pint of distilled water, sulphate of magnesia, 2 oz.; and carbonate of soda, 2⁄2 oz. Heat the solution of sulphate of magnesia to the boiling point, add the solution of carbonate of soda, and boil together until carbonic acid ceases to be evolved. Collect the precipitated carbonate of magnesia, and wash until what passes ceases to give a precipitate with chloride of barium. Mix the precipitate with a pint of distilled water, and in a suitable apparatus, charge with pure washed carbonic acid gas. Retain excess of carbonic acid under pressure for 24 hours. Filter to remove undissolved carbonate, and again pass carbonic acid into the solution. Keep in a bottle securely closed. (This contains about 13 gr. of carbonate of magnesia in each fluid ounce.)

Solution of Carbonate of Potas′sa. Syn. Oil of tartar†, Water of subcarbonate of potash†; Liquor potassæ carbonatis (Ph. L. & D.), L. p. subcarbonatis†, L. Prep. (Ph. L.) Carbonate of potassa, 20 oz. (10 oz.—Ph. D.); water, 1 pint; dissolve and filter (or decant). Sp. gr.—Ph. L., 1·473; Ph. D., 1·310.—Dose, 10 drops to 1 dr., as an antacid, &c.

Solution of Carbonate of So′da. Syn. Subcarbonate of soda water†; Sodæ carbonatis liquor (Ph. D.), L. Prep. (Ph. D.) Carbonate of soda (in crystals), 1⁄2 oz.; distilled water, 1 pint. Sp. gr. 1·026.—Dose, ⁄4 to 1⁄2 fl. oz., as an antacid; in heartburn, dyspepsia, &c.

Solution of Chloride of Antimony. Syn. Antimonii chloridi liquor (B. P.). Prep. Dissolve black sulphide of antimony in boiling hydrochloric acid. Used as an escharotic, and in the preparation of oxide of antimony.

Solution of Chlo′′ride of Ar′senic. Syn. Liquor arsenici hydrochloricus (B. P.), Liquor arsenici chloridi (Ph. L.), L. Prep. 1. (Ph. L.) Arsenious acid (in coarse powder), ⁄2 dr.; hydrochloric acid, 1⁄2 fl. dr.; distilled water, 1 fl. oz.; boil until the solution of the arsenious acid is complete, and, when cold, add enough distilled water to make the whole exactly measure a pint.—Dose, 4 to 5 drops.

2. (B. P.) Arsenious acid, 80 gr.; hydrochloric acid, 2 dr.; distilled water, 20 oz.; boil the two acids with 4 oz. of the water until a solution is effected, then add sufficient distilled water to make up 20 oz.—Dose, 2 to 8 minims.

Solution of Chloride of Ba′′rium. Syn. Solution of muriate of baryta†; Liquor barii chloridi (Ph. L. & D.), Solutio barytæ muriatis (Ph. E.), L. Prep. (Ph. L. & E.) Dissolve chloride of barium, 1 dr. (1 oz.—Ph. D.), in water, 1 fl. oz. (8 oz. Ph. D.), and filter the solution. Sp. gr. (Ph. D.) 1·088.—Dose, 5 drops, gradually increased to 10 or 12, twice or thrice daily; in scrofula, scirrhous affections, and worms; externally, largely diluted, as a lotion in scrofulous ophthalmia.

Solution of Chloride of Cal′cium. Syn. Solution of muriate of lime†; Calcii chloridi liquor (Ph. D.), Calcis muriatis solutio (Ph. E.). Prep. 1. (Ph. L. 1836.) Fused chloride of calcium, 4 oz. (crystals, 8 oz.—Ph. E.); water, 12 fl. oz.; dissolve, and filter.

2. (Ph. D.) Fused chloride of calcium, 3 oz.; water, 12 oz. Sp. gr. 1·225.—Dose, 10 drops to 1 dr., or more; in scrofulous and glandular diseases, &c.

Solution of Chloride of Zinc. Syn. Liquor zinci chloridi (B. P.). Prep. Granulated zinc, 8; hydrochloric acid, 22; solution of chlorine, q. s.; carbonate of zinc, ⁄4; distilled water, 10. Mix the acid and water in a porcelain dish, add the zinc, and apply a gentle heat to promote the action until gas is no longer evolved; boil for half an hour, supplying the water lost by evaporation, and allow the product to cool. Filter it into a bottle, and add solution of chlorine by degrees, with frequent agitation until a brown sediment appears. Filter the liquid into a porcelain basin, and evaporate until it is reduced to the bulk of 20.

Solution of Chlo′′rinated Lime. Syn. Bleaching liquid, Solution of chloride of lime‡, S. of hypochlorite of lime; Solutio calcis hypochloris, S. calcis chloridi, Calcis chlorinatæ liquor (Ph. D.), L. Prep. 1. (Ph. D.) Chlorinated lime (‘chloride of lime’), ⁄2 lb.; water, ⁄2 gall.; triturate them together, then transfer the mixture to a stoppered bottle, and shake it repeatedly for the space of 3 hours; lastly, filter through calico, and preserve it in a well-stopped bottle.

2. Chloride of lime (dry and good, and rubbed to fine powder), 9 lbs.; tepid water, 6 galls.; mix in a stoneware bottle capable of holding 8 galls., agitate frequently for a day or two, and, after 2 or 3 days’ repose, decant the clear portion, and keep it in well-corked bottles, in a cool situation. If filtered, it should be done as rapidly as possible, and only through coarsely powdered glass in a covered vessel.

3. Liquor calcis chloratæ (B. P.). Prep. Blend well together, by trituration in a large mortar, 1 lb. of chlorinated lime with 1 gall. of water, transfer the mixture to a stoppered bottle, and shake it frequently for the space of 3 hours; pour it on a calico filter, and let the solution which passes through be kept in a well-stoppered bottle. Sp. gr. 1·035.

Obs. The last is the usual strength sold in trade, under various attractive names, to give it importance. It is used as a disinfectant, bleacher, and fumigation; and, diluted with water, as a lotion, injection, or collyrium, in several diseases. See Hypochlorite of Calcium.

Solution of Chlorinated lime, Spirituous. Syn. Solutio calcis chloridi, spirituosa. (Chevallier). Prep. Chloride of lime, 3 dr.; distilled water, 2 oz.; rectified spirit, 2 oz. Mix and filter.

Solution of Chlorinated Potas′sa. Syn. Solution of chloride of potash‡, S. of hypochlorite of potassa, Javelle’s bleaching liquid; Solutio potassæ hypochloris, Liquor potassæ chloridi, L. potassæ chlorinatæ, L.; Eau de Javelle, Fr. Prep. 1. Dissolve carbonate of potassa, 1 part, in water, 10 parts, and pass chlorine gas through the solution to saturation.

2. Chloride of lime (dry and good), 1 part; water, 15 parts: agitate them together for an hour; next dissolve of carbonate of potassa, 2 oz., in water, ⁄4 pint; mix the two solutions, and after a time either decant or filter.—Uses, &c. As the last.

Solution of Chlorinated Soda. Syn. Solution of chloride of soda‡, S. of hypochlorite of soda, Labarraque’s disinfecting liquid; Solutio sodæ hypochloris, Hypochloris sodicus aqua solutus (P. Cod.), Liquor sodæ chlorinatæ (Ph. L. & D.), L. Prep. 1. (Ph. L.), Carbonate of soda (in crystals), 1 lb.; water, 1 quart; dissolve, and pass through the solution the chlorine evolved from a mixture of common salt, 4 oz.; binoxide of manganese, 3 oz.; sulphuric acid, 2⁄2 fl. oz. (4 oz.—Ph. L. 1836); diluted with water, 3 fl. oz.; placed in a retort, heat being applied to promote the action, and the gas being purified by passing through 5 fl. oz. of water before it enters the alkaline solution.

2. (Ph. D.) Chlorinated lime, ⁄2 lb., and water, 3 pints, are triturated together in a marble mortar, after which the mixture is transferred to a stoppered bottle, agitated frequently during three hours, and then filtered through calico; in the mean time carbonate of soda (cryst.), 7 oz., is dissolved in water, 1 pint; the two solutions are next mixed, and, after agitation for about 10 minutes, the whole is filtered as before. The filtrate is to be preserved in a well-stopped bottle.

3. (B. P.) Dissolve 12 oz. of carbonate of soda in 36 oz. of distilled water, and put the solution into a glass vessel. Mix black oxide of manganese, 4 oz., and hydrochloric acid, 15 fl. oz., in a glass flask, with a bent tube attached by means of a cork to its mouth, apply a gentle heat, and with a suitable arrangement cause the gas evolved to pass first through a wash-bottle containing 4 oz. of water, and then into the solution of carbonate of soda, regulating heat so that the gas shall be slowly but constantly introduced. When the disengagement of chlorine has ceased, transfer the solution which has absorbed it to a stoppered bottle, and keep in a cool and dark place. Sp. gr. 1·103.

Obs. This solution is used as an antiseptic, disinfectant, and bleaching liquid.—Dose, 20 to 30 drops, in any bland fluid, in scarlet fever, sore throat, &c.; it is also made into a lotion, gargle, injection, and eye-water. Meat in a nearly putrid state, unfit for food, is immediately restored by washing or immersion in this liquid.

Solution of Chlo′′rine. Syn. Chlorine water; Solutio chlorinii, Liquor chlorini (Ph. L. & D.), Chlorinei aqua (Ph. E.), L. Prep. 1. (Ph. L.) On binoxide of manganese (in powder), 2 dr., placed in a retort, pour hydrochloric acid, 1 fl. oz., and pass the chlorine in distilled water, ⁄2 pint, until it ceases to be evolved.

2. (Ph. E.) Muriate of soda (common salt), 60 gr.; red oxide of lead, 350 gr.; triturate them together, and put them into 8 fl. oz. of distilled water, contained in a stoppered bottle; then add of sulphuric acid, 2 fl. dr.; and having replaced the stopper, agitate the whole, occasionally, until the oxide of lead turns white; lastly, after subsidence, pour off the clear liquid into another stoppered bottle.

3. (Ph. D.) Introduce into a gas bottle peroxide of manganese (in fine powder), ⁄2 oz.; add of hydrochloric acid, 3 fl. oz., (diluted with) water, 2 fl. oz.; apply a gentle heat, and cause the evolved gas to pass through water, 2 fl. oz., and then into a 3-pint bottle containing distilled water, 20 fl. oz., and whose mouth is loosely plugged with tow; when the air has been entirely displaced by the chlorine, cork the bottle loosely, and shake it until the chlorine is absorbed; it should now be transferred to a pint stoppered bottle, and preserved in a dark and cool place.

(B. P.) Liquor chlori. Prep. Put 1 oz. of black oxide of manganese, in fine powder, into a gas bottle, and having poured upon it 6 fl. oz. of hydrochloric acid, diluted with 2 oz. of distilled water, apply a gentle heat, and by suitable tubes cause the gas, as it is developed, to pass through 2 oz. of distilled water placed in an intermediate small phial, and thence to the bottom of a 3-pint bottle containing 30 oz. of distilled water, the mouth of which is loosely plugged with tow. As soon as the chlorine ceases to be developed, let the bottle be disconnected from the apparatus in which the gas has been generated, corked loosely, and shaken until the chlorine is absorbed. Lastly, introduce the solution into a green bottle furnished with a well-fitting stopper, and keep it in a cool and dark place. Sp. gr. 1·003. One fluid ounce contains 2·66 grains of chlorine.

Prop., &c. Irritant and acrid, but, when largely diluted, stimulant and antiseptic.—Dose, ⁄2 to 2 fl. dr., in ⁄2 pint of water, sweetened with a little sugar, in divided doses, during the day; in scarlatina, malignant sore throat, &c. On the large scale, liquid chlorine may be procured by passing the gas obtained by any of the methods named under Chlorine into water, until it will absorb no more.

Solution of Cit′rate of Ammo′′nia. Syn. Liquor ammoniæ citratis (B. P., Ph. L.), L. Prep. (Ph. L.) Dissolve citric acid, 3 oz., in distilled water, 1 pint; and to the solution add of sesquicarbonate of ammonia (in powder), 2⁄2 oz., or q. s. to exactly neutralise the liquor.—Dose, 2 to 6 fl. dr.

Solution of Citrate of Magne′sia. Syn. Solution magnesiæ citratis. See Magnesium, Citrate of.

(B. P.) Carbonate of magnesia, 100 gr.; citric acid, 200 gr.; syrup of lemons, ⁄2 fl. oz.; bicarbonate of potash in crystals, 40 gr.; water, q. s. Dissolve the citric acid in 2 oz. of the water, and having added the carbonate of magnesia, stir until it is dissolved. Filter the solution into a strong half-pint bottle, add the syrup and water sufficient to nearly fill the bottle, then introduce the bicarbonate of potash, and immediately close the bottle with a cork, which should be secured with string or wire, afterwards shake till the bicarbonate has dissolved.—Dose, 5 to 10 fl. oz.

Solution of Citrate of Morphia. Syn. Liquor morphiæ citratis, Solutio m. c., L. Prep. (Magendie.) Pure morphia, 13 gr.; citric acid, 8 or 10 gr.; water, 1 fl. oz.; tincture of cochineal, 2 fl. dr.—Dose, 3 to 12 drops.

Solution of Citrate of Potash. Syn. Liquor potassæ citratis. Neutral mixture. (Ph. U. S.) Prep. Citric acid, ⁄2 troy oz.; bicarbonate of potash, 330 gr.; water, 8 oz.

Solution of Copai′ba. See Solution, Specific.

Solution of Cor′rosive Sub′limate. Syn. Solution of chloride of mercury; Liquor hydrargyri bichloridi† (Ph. L.). Prep. 1. (Ph. L.) Corrosive sublimate and sal ammoniac, of each 10 gr.; water, 1 pint, dissolve.—Dose. As an alterative, 10 to 30 drops; as an antisyphilitic, ⁄2 to 2 fl. dr., in simple or sweetened water. It must not be allowed to touch anything metallic. It also forms a most useful lotion in various skin diseases.

2. See Lotion, Mercurial.

Solution of Cyanide of Potassium. Syn. Liquor potassii cyanidi. (Laming.) Prep. Cyanide of potassium, 22 gr.; proof spirit, 9 fl. dr. This is the strength of his hydrocyanic acid, which contains 1 gr. of real acid in 1 fl. dr. Magendie’s medicinal hydrocyanate of potash consists of cyanide of potassium dissolved in 8 times its weight of distilled water.

Solution of Delphinia. Syn. Solutio delphiniæ. (Dr Turnbull.) Delphinia, 1 scruple; rectified spirit, 2 oz. For outward use.

Solution of Diac′etate of Lead. See Solution of Subacetate of Lead.

Solution, Donovan’s. See Solution of Hydriodate of Arsenic and Mercury (below).

Solution, Escharotic (Freyburg’s). Syn. Solutio escharotica, L. Prep. From camphor, 30 gr.; corrosive sublimate, 60 to 100 gr.; rectified spirit, 1 fl. oz.; dissolve. In syphilitic vegetations, and specially condylomes. It is spread over the diseased surface, either at once or after the application of a ligature.

Solution of Flints. Syn. Liquor of flints; Liquamen silicum, Liquor potassæ silicatis, L. Prep. 1. Soluble glass dissolved in water.

2. (Bate.) Powdered quartz, 1 part; dry carbonate of potash, 2 parts (3 parts—Turner); triturate them together, fuse the mixture in a Hessian crucible, and allow the resulting glass to deliquesce by exposure in a damp situation.—Dose, 5 or 6 to 30 drops; in gouty concretions, stone, &c. “It resolves the stone, and opens obstructions.” See Soluble glass.

Solution, Gannal’s. { See Solution for

Solution, Goadsby’s. { Anatomical preparations.

Solution, Goulard’s. See Solution of Subacetate of Lead.

Solution, Hahnemann’s Prophylac′tic. Syn. Liquor belladonnæ, Solutio prophylactica, L. Prep. From extract of belladonna (alcoholic), 3 gr.; distilled water, 6 fl. dr.; rectified spirit, 2 fl. dr.; dissolve. Used against scarlet fever.—Dose, 2 or 3 drops for a child under 12 months; and an additional drop for every year above that age to maturity.

Solution of Hartshorn, Succinated. Syn. Liquor cornu cervi succinatus. (P. Cod.) Neutralise true spirits of hartshorn (or a solution of 1 oz. of salt of hartshorn in 1 oz. of water) with acid of amber.

Solution of Hydri′odate of Ar′senic and Mer′cury. Syn. Donovan’s solution; Solutio arsenici et hydrargyri iodidi, Arsenici et hydrargyri hydriodatis liquor. (Ph. D.), L. Prep. 1. (Donovan.) Triturate metallic arsenic, 6·08 gr., mercury, 15·38 gr., and iodine, 50 gr., with alcohol, 1 fl. dr., until dry; to this add, gradually, of distilled water, 8 fl. oz., and again well triturate; next put the whole into a flask, add of hydriodic acid, ⁄2 fl. dr., and boil for a few minutes; lastly, when cold, add distilled water, q. s. to make the whole measure exactly 8 fl. oz.

2. (Ph. D.) Pure arsenic (in fine powder), 6 gr.; pure mercury, 16 gr.; pure incline, 50⁄2 gr.; alcohol, ⁄2 fl. dr.; triturate as before, add, gradually, of water, 8 fl. oz., heat the mixture until it begins to boil, and, afterwards, make up the cold and filtered solution to exactly 8 fl. oz. 6 fl. dr.

3. (Wholesale.) From metallic arsenic, 61 gr.; iodine, 500 gr.; mercury, 154 gr.; rectified spirit, 1⁄2 fl. oz.; distilled water, 2 quarts; hydriodic acid, 5 fl. dr.; as No. 1; the product being made up with distilled water so as to measure exactly 4 pints, or 80 fl. oz., or to weigh 5 lbs. 1⁄4 oz. (av.), when cold.

Obs. Great care must be taken that the whole of the arsenic be dissolved, which can only be effected by the most careful trituration. Soubeiran recommends the employment of 1 part, each, of the respective iodides, with 98 parts of water, as furnishing a simpler and equally effective product, proportions which are almost exactly those employed by Mr Donovan.—Dose, 10 to 30 drops, twice or thrice a day, preferable soon after a meal; in lepra, psoriasis, lupus, and several other scaly skin diseases. It is a most valuable medicine in these affections.

Solution of Hydrochlo′′rate of Mor′phia. Syn. Solution of muriate of morphia; Liquor morphiæ hydrochloratis (Ph. L.), Solutio morphiæ muriatis (Ph. E.), Morphiæ muriatis liquor (Ph. D.), L. Prep. 1. (Ph. L.) Hydrochlorate of morphia, 4 dr.; proof spirit, ⁄2 pint; distilled water, 1 pint; dissolve by the aid of a gentle heat. 60 drops (minims) of this solution contain 1 gr. of hydrochlorate of morphia.—Dose, 5 to 15 or 20 drops.

2. (Ph. E. & D.) Muriate of morphia, 90 gr.; rectified spirit, 5 fl. oz.; distilled water, 15 fl. oz. 107 drops (minims) contain 1 gr. of the hydrochlorate.—Dose, 10 to 30 or 40 drops, or nearly as laudanum.

3. (Apothecaries’ Hall.) Muriate of morphia, 16 gr.; rectified spirit, 1 fl. dr.; water, 1 fl. oz.; 30 drops (minims) contain 1 gr.—Dose, 3 to 10 drops. See Solution of Acetate of Morphia, &c.

Solution of Hypochlo′′rite of Lime. Solution of chlorinated lime.

Solution of I′odide of Ar′senic. Syn. Liquor arsenici periodidi, L. Prep. (Wackenroder.) Each drachm contains ⁄8 gr. of teriodide of arsenic; equivalent to ⁄48 gr. of metallic arsenic, and ⁄10 gr. (nearly) of iodine.

Solution of Iodide of Mer′cury and Potas′sium. Syn. Liquor iodohydrargyratis potassii iodidi, L. Prep. (Dr Channing.) Iodide of potassium, 3⁄2 gr.; binoxide of mercury, ⁄2 gr.; distilled water, 1 fl. oz.; dissolve.—Dose, 2 to 5 or 6 drops, three times a day, much diluted; in dyspepsia, indurations, enlargement of the spleen, dropsy, &c.

Solution of Iodide of Potas′sium (Compound). Syn. Ioduretted water, Compound solution of iodine; Liquor potassii iodidi compositus (Ph. L. & D.), Liquor iodinei COMPOSITUS (Ph. E.), L. Prep. 1. (Ph. L. & D.) Iodide of potassium, 10 gr.; iodine, 5 gr.; water, 1 pint; dissolve.—Dose, 1 to 6 dr.; in the usual cases where iodine is employed.

2. (Ph. E.) Iodide of potassium, 1 oz.; iodine, 2 dr.; water, 16 fl. oz. This is 30 times as strong as the preceding.—Dose, 5 to 20 drops.

Solutions of Iodine. Syn. Liquor iodi (B. P.). Prep. Dissolve 20 gr. of iodine and 30 gr. of iodide of potassium in 1 oz. of distilled water. (Lugol’s.) Syn. Solutiones iodinii vel ioduretæ. Prep. Ioduretted waters, Nos. 1, 2, and 3; iodine, 1⁄2 gr., 2 gr., and 2⁄2 gr.; water, 1 pint. Drops.—Iodine, 1 scruple; iodide of potassium, 2 scruples; water, 9 dr. Lotions, &c.—Iodine, 1⁄2 gr. to 3 gr.; iodide of potassium, 3 gr. to 6 gr.; water, 1 pint. Rubefacient.—Iodine, 1 pint; iodide of potassium, 2 parts; water, 12 parts. Caustic.—Iodine, 1 part; iodide of potassium, 1 part; water, 2 parts.

Solution of Iodide of Iron. Syn. Liquor ferri Iodidi. (Ph. U. S.). Prep. Mix 2 oz. (troy) of iodine with 5 oz. of water, and add 1 oz. (troy) of iron filings, stir frequently, and heat the mixture gently till it assumes a greenish colour; then filter into a glass bottle containing 12 oz. of powdered sugar, and after it has passed, pour distilled water on the filter, until the filtered liquor, including the sugar, measures 20 oz., last shake the bottle till the sugar is dissolved.—Dose, 15 minims to 1 dr.

Solution of Iodine with Hemlock. Syn. Solutio iodinii cum conio. Dr Scudamore’s solution. For inhaling. Iodine, 6 gr.; iodide of potassium, 6 gr.; rectified spirit, 2 dr.; water, 5 oz. 6 dr. From ⁄2 dr. to 5 dr. of this solution, with ⁄2 dr. of tincture of hemlock to be added to warm water at 120° F. in a glass inhaler, and used twice a day. Two thirds of the ingredients are first put into the inhaler, and the rest added when half the time for inhaling has elapsed.

Solution of I′ron (Alkaline). Syn. Liquor ferri alkalini, L. Prep. (Ph. L. 1824.) Iron filings, 2⁄2 dr.; nitric acid, 2 fl. oz.; water, 6 fl. oz.; dissolve, decant, gradually add of solution of carbonate of potash 6 fl. oz., and in 6 hours decant the clear portion. This was intended as an imitation of Stahl’s Tinctura Martis Alkalina. It is tonic, emmenagogue, &c.—Dose, 20 to 60 drops.

Solution of Iron and Alum. Syn. Solutio ferri aluminosa. (Swediaur.) Calcined sulphate of iron, 10 scruples; alum, 5 scruples; water sufficient to dissolve them; sulphuric acid, 15 drops.—Dose, 10 to 15 drops. Once a celebrated nostrum in Germany, under the name of Tinctura nervosa.

Solution, Javelle’s. See Solution of Chlorinated potash.

Solution, Labarraque’s. See Solution of Chlorinated soda.

Solution of Lime. Syn. Lime water; SOLUTIO CALCIS HYDRATIS, Liquor calcis (Ph. L. & D.), Aqua calcis (Ph. E.), L. Prep. (Ph. L.) Upon the lime, ⁄2 lb., first slaked (by sprinkling it) with a little of the water, pour the remainder of water, 12 pints, and shake them well together (for 5 minutes—Ph. D.); immediately cover the vessel, and set it aside for three hours; then keep the solution with the remaining lime (equally divided) in stoppered glass vessels, and, when it is to be used, decant the required portion from the clear solution (replacing it with more water, and agitating briskly, as before—Ph. E.).

Liquor Calcis (B. P.). Syn. Lime water. Put 2 oz. of slaked lime into a stoppered bottle containing 1 gall. of distilled water, and shake well for two or three minutes. After 12 hours the excess of lime will have subsided, and the clear solution may be drawn off with a siphon as it is required for use, or transferred to a green glass bottle furnished with a well-ground stopper.

Obs. Cold water dissolves more lime than hot water. 1 pint of water at 32° Fahr. dissolves 13⁄4 gr., at 60° it dissolves 11⁄2 gr., but at 212° only 6⁄2 gr. (Phillips.)

Uses, &c. Lime water is antacid, astringent, antilithic, tonic and vermifuge.—Dose. A wine-glassful, or more, 2 or 3 times a day, in milk or broth; in dyspepsia, diarrhœa, calculous affections, &c.; and, externally, as a detersive and discutient lotion.

Solution of Lime (Saccharated). (B. P.) Syn. Liquor calcis saccharatus. Prep. Slaked lime, 1; refined sugar (in powder), 2; distilled water, 20; digest for some hours and strain.—Dose, 15 to 60 minims in milk.

Solution of Lithia, Effervescing. Syn. Liquor lithiæ effervescens. (B. P.) Prep. Mix 10 gr. of carbonate of lithia and 1 pint of water in a suitable apparatus, and charge with carbonic acid gas under a pressure of 7 atmospheres. Keep in bottles securely corked.

Solution, Mackenzie’s. Prep. From nitrate of silver, 20 gr., dissolved in distilled water, 1 fl. oz. Used to wash the throat and fauces, and to sponge the trachea, in affections of those parts.

Solution of Magne′sia. Syn. Aerated magnesia water, Carbonated m. w., Fluid magnesia, Condensed solution of m., Concentrated s. of m.; Liquor magnesiæ carbonatis, Aqua m. c., L.; Eau magnesienne, Fr. Prep. (Dinneford’s.) Water and Howard’s heavy carbonate of magnesia, in the proportion of 17⁄2 gr. of the latter to every fl. oz. of the former, are introduced into a cylindrical tinned copper vessel, and carbonic acid, generated by the action of sulphuric acid on whiting, is forced into it by steam power for 5⁄2 hours, during the whole of which time the cylinder is kept in motion. Sir J. Murray’s is similar. The Paris Codex orders recently precipitated carbonate of magnesia to be used while still moist. Antacid and laxative. See Fluid magnesia.

Solution, Min′eral. See Solution of Arsenite of Potassa.

Solution of Mor′phia. See Solutions of Acetate, Hydrochlorate, and Sulphate.

Solution of Myrrh, Alkaline. Syn. Solutio myrrhæ alkalina. (Swediaur.) Prep. Carbonate of soda, 1 dr.; myrrh, 2 oz.; boiling water, 8 oz. Digest in a water bath for 2 days, frequently stirring, and strain.

Solution of Nitrate of Mercury (Acid). Syn. Liquor hydrargyri nitratis acidus (B. P.). Prep. Mercury, 4; nitric acid, 5; distilled water, 1⁄2; mix the nitric acid with the water in a flask, and dissolve the mercury in the mixture without the application of heat. Boil gently for 15 minutes, cool, and preserve the solution in a stoppered bottle. Used alone, as a caustic; 1 to 2 minims to 1 oz. of water, as a gargle; and 1 minim to 2 oz. of water, as an injection in gonorrhœa.

Solution of Nitrate of Mercury and Ammonia. Syn. Solutio hydrargyri et ammoniæ nitratis. Ward’s white drop. Prep. Nitrate of ammonia and mercury in crystals, 1 part; rose water, 3 parts; digest till dissolved.

Solution of Nitrate of Sil′ver. Syn. Liquor argenti nitratis (Ph. L.), Solutio a. n. (Ph. E.), L. Prep. (Ph. L.) Nitrate of silver (cryst.), 1 dr. (40 gr.—Ph. E.); distilled water, 1 fl. oz. (1600 gr.—Ph. E.); dissolve. Used as an escharotic, &c. It should be kept from the light. See Lotion, Nitrate of Silver, &c.

Solution of O′pium (Sed′ative). See Liquor.

Solution of Oxysulphate of Iron‡. Syn. Liquor ferri oxysulphatis, L. Prep. From sulphate of iron (in powder) and nitric acid, of each 3 dr.; triturated together for 15 minutes, and then dissolved in distilled water, 1⁄2 fl. oz.—Dose, 5 or 6 to 12 drops.

Solution of Perchloride of Iron. Syn. Liquor ferri perchloridi (B. P.). Prep. Stronger solution of perchloride of iron (see below), 1; distilled water, 3.—Dose, 10 to 30 minims.

Solution of Perchloride of Iron (Stronger). Syn. Liquor ferri perchloridi fortior (B. P.). Prep. Iron wire, 2 oz.; hydrochloric acid, 12 oz.; nitric acid, 9 dr.; distilled water, 8 gr. Mix 8 of the hydrochloric acid with the water, and pour the mixture on the iron wire, applying a gentle heat, so that the whole of the metal may be dissolved; filter the solution, and add to it the remainder of the hydrochloric and nitric acids; heat the mixture briskly, until, on the sudden evolution of red fumes, the liquid becomes of an orange-brown colour, then evaporate by the heat of a water bath until it is reduced to 10 fl. oz. Used as an application to diphtheritic patches, for injecting nævi, as a powerful styptic, and in the preparation of Solution of Perchloride of Iron. (See above.)

Solution of Perchloride of Mercury. Syn. Liquor hydrargyri perchloridi (B. P.). Prep. Corrosive sublimate, 10 gr.; chloride of ammonium, 10 gr.; distilled water, 20 oz.; dissolve.—Dose, 30 to 120 minims.

Solution of Perchloride of Mercury (Compound). Syn. Liquor hydrargyri, Perchloridi compositus, Liquor mercurielle normale (Mialhe). Prep. Distilled water, 16 oz,; chloride of sodium, 16 gr.; chloride of ammonium, 16 gr.; white of 1 egg, perchloride of mercury, 4 gr. Beat the white of egg with the water, filter, dissolve the salts in the liquid and filter again.

Solution of Permanganate of Potassa. Syn. Liquor potassæ permanganatis (B. P.). Prep. Permanganate of potassa, 4 gr.; distilled water, 1 oz.; dissolve. Diluted with 40 parts of water, it is used as a gargle or as a cleansing wash for diseased surface.—Dose, 2 to 4 dr.

Solution of Perni′trate of Iron. Syn. Solution of persesquinitrate of iron; Ferri pernitras liquor (Ph. D.), Solutio persesquinitras ferri (Kerr), L. Prep. (Ph. D.). Take of pure nitric acid, 3 fl. oz.; water, 16 fl. oz.; mix, add fine iron wire, 1 oz.; dissolve, and to the clear solution add as much water as will make the whole measure 1⁄2 pint. Sp. gr. 1·107.—Dose, 5 or 6 to 30 drops, or more; in passive hæmorrhages, mucous discharges, chronic diarrhœa with prostration, &c.

Solution of Persulphate of Iron. Syn. Liquor ferri persulphatis. Prep. Sulphate of iron, 8; sulphuric acid, ⁄4; nitric acid, ⁄4; distilled water, 12. Add the sulphuric acid to 10 of the water, and dissolve the sulphate of iron in the mixture with the aid of heat. Mix the nitric acid with the remaining 2 of the water, and add the dilute acid to the solution of sulphate of iron. Concentrate the whole by boiling until, by the sudden evolution of ruddy vapours, the liquid ceases to be black, and acquires a red colour. A drop of the solution is now to be tested with ferricyanide of potassium, and if a blue precipitate be formed, a few additional drops of nitric acid should be added, and the boiling renewed, in order that the whole may be converted into persulphate of iron. When the solution is cold, make up the quantity to 11 by the addition, if necessary, of distilled water. Used in making several preparations of iron; it is also a good styptic.

Solution of Phosphoric Ether. Syn. Solutio phosphori ætherea. Prep. Sliced phosphorus, 5 gr.; rectified ether, 1 oz.; mix, set the bottle in a dark place for 3 or 4 days, shaking occasionally, and decant.

Solution for Plate. Syn. Plate liquor; Solutio pro argento, L. Prep. From alum, cream of tartar, and common salt, of each 1 oz.; water, ⁄2 gall.; dissolve. Used to increase the lustre and whiteness of silver plate, the articles being boiled in it.

Solution of Potas′sa. Syn. Solution of hydrate of potassa, Liquor of potassa, Potash water, Caustic p. w.; Liquor potassæ (B. P., Ph. L.), Aqua potassæ (Ph. E.), Potassæ causticæ liquor (Ph. D.), Aqua kali puri†, Lixivium saponarum†, Aqua kali causticum†, Lixivium causticum†, L. Prep. 1. (Ph. L.) Lime (recently burnt), 8 oz.; boiling distilled water, 1 gall.; sprinkle a little of the water on the lime in an earthen vessel, and, when it is slaked and fallen to powder, add of carbonate of potassa 15 oz., dissolved in the remainder of the water; bung down, and shake frequently, until the mixture is cold, then allow the whole to settle, and decant the clear supernatant portion into perfectly clean and well-stoppered green-glass bottles. Sp. gr. 1·063. It contains 6·7% of pure potassa.

2. (Ph. E.) Carbonate of potassa (dry), 4 oz.; quicklime, 2 oz.; water, 45 fl. oz.; boiling briskly for a few minutes after each addition of the milk of lime; to yield at least 35 fl. oz., by decantation, after 24 hours’ repose in a deep, narrow, glass vessel. Sp. gr. 1·072.

3. (Ph. D.) Pure carbonate of potassa, 1 lb.; distilled water, 1 gall.; dissolve, heat the solution to the boiling point in a clean iron vessel, gradually add to it of fresh quicklime, 10 oz., previously slaked with water, 7 fl. oz., and continue the ebullition for 10 minutes, with constant stirring; next allow it to cool out of contact with the air, and, when perfectly clear, decant it by means of a syphon, and bottle it as before. Sp. gr. 1·068.

4. (B. P.) Carbonate of potash, 2; slaked lime, 1⁄2; distilled water, 20; dissolve the carbonate of potash in the water, and having heated the solution to the boiling point in a clean iron vessel, gradually mix the slaked lime, and continue the ebullition for 10 minutes with constant stirring; decant the clear liquid.—Dose, 15 to 60 minims 3 times a day in beer, milk, or Mistura Amygdalæ.

5. (Wöhler.) Nitrate of potassa, 1 part, is mixed, in alternate layers, with clippings of sheet copper, 2 or 3 parts, and then heated to moderate redness for about ⁄2 an hour in a copper or iron crucible; when cold, the potassa is washed out with distilled water, and the solution, after repose in a closed vessel, decanted as before. Not a trace of copper can be detected in the liquid. The clippings may be again used if mixed with a little fresh metallic copper.

6. (Wholesale.) From carbonate of potash (kali), 1 lb., and quicklime, ⁄2 lb., to each gall. of water.

7. (Brandish’s alkaline solution; Liquor potassæ Brandishii.) From American pearlashes, 6 lbs.; quicklime and wood ashes (from the ash), of each 2 lbs.; boiling water, 6 galls. (old meas.); to each gall. of the clear product is added 12 or 15 drops of oil of juniper. This ‘solution’ is much asked for in trade. Ordinary liquor of potassa is generally sold for it.

Pur. “Nothing, or scarcely anything, is thrown down from this solution on the addition of lime water; and when it has been first saturated by nitric acid, no precipitate falls on the addition of carbonate of soda, chloride of barium, or nitrate of silver. What is thrown down by bichloride of platinum is yellowish.” (Ph. L.)

Uses, &c. Liquor of potassa is antacid, diuretic, resolvent, and lithontriptic.—Dose, 10 to 30 or 40 drops, in any bland diluent (not acidulous); in heartburn, gout, calculi, indurations, scrofula, lepra, psoriasis, &c.

Obs. Quicklime fails to abstract the carbonic acid from the alkaline carbonates in solutions much stronger than those above referred to. Weaker solutions may, however, be easily concentrated by evaporation in iron vessels. See Potassium, Hydrate of, and below.

Solution of Potas′sa (Effervescing). Syn. Liquor potassæ effervescens (B. P.); Effervescing potash water, Supercarbonate of potassa w.; Aqua potassæ effervescens (Ph. E.), A. p. supercarbonatis, L. Prep. (Ph. L. & E.) Bicarbonate of potash, 1 dr.; distilled water, 1 pint; dissolve, force in carbonic acid gas in excess, and keep it in a well-stoppered bottle. Resembles soda water, but sits better on the stomach. It is almost specific in the early stages of scurvy.

(B. P.) Dissolve 30 gr. of bicarbonate of potash in one pint of distilled water, filter, pass in washed carbonic acid (obtained by the action of sulphuric acid on chalk) up to a pressure of 7 atmospheres. Keep in bottles closely secured.

Obs. An excellent substitute for this preparation is to pour a bottle of soda water into a tumbler containing 20 gr. of powdered bicarbonate of potash, and to drink it immediately.

Solution of Potas′sio-tar′trate of An′timony. Syn. Solutio antimonii potassio-tartratis, Antimonii tartarizati liquor (Ph. D.), L. Prep. (Ph. D.) Tartarised antimony, 1 dr.; rectified spirit, 7 fl. oz.; distilled water, 1 pint; dissolve. Strength, doses, and uses, similar to those of antimonial wine (which see), than which it keeps better.

Solution, Prophylac′tic. See Hahnemann’s solution.

Solution of Protonitrate of Mercury. Syn. Liquor hydrargyri nitrici (PROTO-NITRATIS) (G. Ph.). Prep. Protonitrate of mercury, 1 oz.; distilled water, 9 oz.; nitric acid (1·185), 46 gr. Filter.—Dose, 1 to 5 drops.

Solution of Sesquicar′bonate of Ammonia. See Solution of Carbonate of Ammonia.

Solution of Sil′icate of Potas′sa. See Solution of Flints.

Solution of So′da. Syn. Solution of hydrate of soda, Liquor of soda, Caustic soda water; Liquor sodæ (B. P., Ph. L.), Sodæ causticæ liquor (Ph. D.), L. Prep. 1. (Ph. L.) Carbonate of soda, (cryst.), 32 oz.; lime, 9 oz.; boiling distilled water, 1 gall.; proceed as for solution of potassa. “In 100 gr. are contained 1 gr. of (pure) soda.” (Ph. L.) Sp. gr. 1·061.

2. (Ph. D.) Carbonate of soda (cryst.), 2 lbs.; fresh-burned lime, 10 oz.; water, 1 gall. 7 fl. oz.; as liquor of potassa. Sp. gr. 1·056.

3. (B. P.) Carbonate of soda, 7; slaked lime, 3; distilled water, 40; dissolve the carbonate in the water, boil in a clean iron vessel, gradually mixing the lime, and stirring constantly for ten minutes; decant into a green-glass bottle, with air-tight stopper. Sp. gr. 1·047.—Dose, ⁄2 to 1 dr.

Solution of Soda (Effervescing). Syn. Soda water; Liquor sodæ effervescens, Aqua s. e. (Ph. E.), A. s. supercarbonatis, Sodæ carbonatis aqua acidula, L. Prep. (Ph. E.) Bicarbonate of soda, 1 dr.; distilled water, 1 pint; dissolve, and force carbonic acid gas into the solution under pressure. Used as an antacid and grateful stimulant, often proving gently laxative. The soda water of the shops cannot be substituted for this preparation, as, in opposition to its name, it is usually made without soda. (B. P.) Half the strength.

Solution, Sol′dering. Prep. Dissolve zinc in hydrochloric acid nearly to saturation, add 1-5th part of powdered sal ammoniac, and simmer for 5 minutes. Used to make solder flow easily and take well; applied with a feather. See Soldering.

Solution, Speci′fic (Frank’s). Syn. Specific solution of copaiba; Liquor copaibæ alkalina, L. Prep. Take of balsam of copaiba, 2 parts; liquor of potassa (Ph. L.), 3 parts; water, 7 parts; boil the mixture for 2 or 3 minutes, put it into a separator, and allow it to stand for 5 or 6 days; then draw it off from the bottom, avoiding the upper stratum of oil, and to the clear liquid add of sweet spirit of nitre (perfectly free from acid), 1 part; should it turn foul or milky, a very little liquor of potassa will usually brighten it; if not, place it in a clean separator, and let it stand, closely covered, for a few days, and then draw it off from the bottom as before, when it will be perfectly transparent, without filtering. Some persons add the sweet spirit of nitre whilst the solution is still warm, mix it in as rapidly as possible, and immediately cork or fasten up the vessel. This is a good way when the article is wanted in a hurry, but is objectionable from the loss of spirit thereby occasioned, and the danger, without care, of bursting the separator.

Obs. A receipt for this article, upon the authority of Battley, has been going the round of the pharmaceutical works for many years. It is as follows:—Take 12 oz. of balsam of copaiba, and 6 oz, of calcined magnesia; rub together, add a pint of proof spirit, filter, and then add ⁄2 oz. of sweet spirits of nitre. (‘Gray’s Supplement.’) The product of this formula, utterly unlike ‘Frank’s Specific Solution,’ is a colourless tincture, scarcely flavoured with copaiba, and holding very little of the active matter of the balsam in solution, owing to the compound formed with the magnesia being insoluble in spirit. Such is the affinity of this earth for copaiba (copaibic acid), that it will even take it from caustic potassa. See Copaiba, and its preparations.

Solution of Strychnia. Syn. Liquor strychniæ (B. P.). Prep. Strychnia, in crystals, 4 gr.; dilute hydrochloric acid 6 minims; rectified spirit, 2 dr.; distilled water, 6 dr.; mix the hydrochloric acid with 4 dr. of the water, and dissolve the strychnia in it by means of heat; then add the spirit and the remainder of the water.—Dose, 4 to 10 minims.

Solution of Subac′etate of Lead. Syn. Liquor of subacetate of lead, L. of diacetate of l.†, Goulard’s extract; Liquor plumbi, L. plumbi diacetatis (Ph. L.), Plumbi diacetatis solutio (Ph. E.), Plumbi subacetatis liquor (Ph. D.), L. Prep. 1. (Ph. L.) Acetate of lead, 27 oz.; litharge, in fine powder, 16 oz.; water, 3 quarts; boil for ⁄2 an hour, constantly stirring, and then add enough distilled water to make the whole measure 3 quarts; lastly, filter, if required, and keep it in a closed vessel. The proportions, ordered in the Ph. E. are similar. Sp. gr. 1·260.

2. (Ph. D.) Acetate of lead, 6 oz.; litharge, 4 oz.; distilled water, 1 quart; boil, &c., as before; to produce 1 quart. Sp. gr. 1·066. (B. P.) the same.

3. (Wholesale.) From finely powdered litharge, 32 lbs.; distilled vinegar, 32 galls.; boil in a perfectly bright copper pan for 2 hours, cool, add water to make up 32 galls., again simmer for 1 minute, cover up the vessel, and in an hour decant the clear portion. Common trade strength. (See below.)

Solution of Subacetate of Lead (Dilute). Syn. Goulard, Goulard’s lotion, Goulard’s water; Liquor plumbi diacetatis dilutus (Ph. L.), Plumbi subacetatis liquor compositus (Ph. D.), L. Prep. 1. (Ph. L.) Liquor of diacetate of lead, 1⁄2 fl. dr.; proof-spirit, 2 fl. dr.; distilled water, 1 pint; mix.

2. (Ph. D.) Solution of subacetate of lead and proof spirit, of each 2 fl. oz.; distilled water, ⁄2 gall.; mix, filter, and preserve it in a well-stoppered bottle.

3. (B. P.) Solution of subacetate of lead, 2 fl. dr.; rectified spirit, 2 fl. dr.; distilled water, 19⁄2 oz. Filter through paper.

Obs. Both the above preparations were formerly made with common vinegar, and hence were coloured, but those of the Pharm. are white. If wanted coloured, a little spirit colouring may be added. The stronger liquor is only used diluted; and the dilute solution is now seldom prepared by the wholesale druggist. The last (diluted solution) is employed as a sedative, refrigerant, and astringent wash, in various affections. Both are poisonous. For the antidotes, see Lead.

Solution of Sulphate of Atropia. Syn. Liquor atropiæ sulphatis (B. P.). Prep. Sulphate of atropia, 4 gr.; distilled water, 1 oz.; dissolve.—Dose, 1 to 2 minims.

Solution of Sulphate of Copper. Syn. Liquor cupri sulphatis compositus, Aqua styptica. (Ph. L. 1746). Sulphate of copper, 3 oz.; alum, 3 oz.; sulphuric acid, 2 oz.; (by wt.), water, 24 oz. For external use.

Solution of Sulphate of Indigo. Syn. Liquor indigo sulphatis. Prep. Digest 1 part of powdered indigo in 10 of sulphuric acid; when dissolved dilute it with water. Used as a test.

Solution of Sulphate of Mor′phia. Syn. Liquor morphiæ sulphatis, L. Prep. From sulphate of morphia, as the solution of the acetate or hydrochlorate. The uses, doses, &c., are the same.

Solution of Sulphate of Zinc (Compound). See Solution of Alum, Compound.

Solution of Sul′phuret of Potassium. Syn. Solution of hydrosulphate of potassa; Solutio potassii sulphureti, Liquor potassæ hydrosulphatis, Aqua potassæ sulphureti (Ph. D.), L. Prep. Take of washed sublimed sulphur, 1 part; water of caustic potassa, 11 parts: mix, boil for 10 minutes, filter, and keep the solution in well-closed bottles. Sp. gr. 1·117. The product is a mixed solution of hydrosulphate and hyposulphate of potassa.—Dose, 10 to 60 drops, diluted in water; and, externally, made into a lotion; in itch, and several other eruptive diseases.

Solution of Tartrate of Magnesia. Syn. Liquor magnesiæ tartratis. (Airat.) Prep. Tartaric acid, 15⁄4 oz. troy; distilled water, 20 pints; fresh calcined magnesia, diffused in 16 oz. of distilled water, 3 oz. troy and 1 dr.—Dose. As a purgative, 15 oz.

Solution of Veratria. Syn. Solutio veratriæ. Prep. Veratrine, 1 gr.; distilled water, 2⁄2 oz. Dr Turnbull’s solution, for external use, is—veratria, 1 scruple; rectified spirit, 2 oz.

Solution, Swan’s. Syn. Solutio sodæ hypophosphitis. Prep. Mr. Squire says this contains 3 gr. of the salt in a drachm.

SOL′VENT. Syn. Menstruum, L. The liquid in which any substance is dissolved. The substance dissolved is, occasionally, called the ‘solvend.’ (Kirwan.)

Solvent, Glazier’s. Syn. Glazier’s pickle. From soft soap dissolved in thrice its weight of strong soapers’ lye; or, from freshly slaked lime made into a thin paste or cream with twice its weight of pearlash dissolved in a little water. Very caustic. Used to soften old putty, and to remove old paint.

SOMNAMBULISM. Children are most subjected to sleep-walking. When adults are affected with it the cause may generally be traced to mental exhaustion, over-excitement, or emotional feeling. The most preferable method of awakening a somnambulist, if this be desirable, is by dashing cold water on the face. It is well to occasionally administer an aperient, and also to rectify any errors of diet, if necessary, and to remove by the exercise of judicious and kindly advice, and change of scene undue excitement or morbid feeling.

The other precautions, such as securing the feet, &c., during sleep, guarding the exits of the bed-chamber, are so obvious as to need no further allusion to.

SOOT. Syn. Fuligo. Wood soot was formerly officinal, and reputed vermifuge and antiseptic. The soot from pit-coal contains, besides empyreumatic matter, sulphate of ammonia; hence it is valuable as a manure, when not too freely applied. It is also employed by gardeners to kill insects.

SOPORIF′ICS. Hypnotics (which see).

SORBITE. A crystalline saccharine substance resembling mannite, obtained by Boussingault from the berries of the mountain ash. It was obtained from the liquid containing the undecomposed saccharine matter remaining after the juice of the berries had been subjected to fermentation.

SOU′JEE. Syn. Soojee. A species of semolina. Semoletta (semola rarita) is a still smaller variety of pearled wheat, separated from the others by means of a sieve. ‘Baster’s soojee’ is said to be a mixture of ordinary wheat flour and sugar.

SOUR KROUT. See Sauer-krout.

SOUP. A strong decoction of flesh, properly seasoned with salts, spices, &c., for the table. The different tastes of people require more or less of the flavour of spices, salt, garlic, butter, &c., which can, therefore, never be ordered by general rules. If the cook has not a good taste, and attention to that of his or her employers, not all the ingredients which nature and art can furnish will give an exquisite flavour to the dishes. The proper articles should be always at hand, and must be proportioned until the true zest be obtained. A variety of flavours may be given to different dishes served at the same time, or even to the same soup, by varying the condiments and spices. At a Parisian restaurant one cauldron is made to produce almost every imaginable variety of soup.

Soup, Cabbage, Cheap. Wash a large cabbage and cut it into narrow strips, throwing them into ⁄2 a gallon of boiling water, containing 2 oz. of butter. Let it boil for an hour and a half; then add half a pint of milk and flavour with pepper and salt. Serve when hot.

Soup, Carrot. Ingredients required.—4 quarts of liquor in which a leg of mutton or beef has been boiled, a few beef bones, 6 large carrots, 2 large onions, 1 turnip, seasoning of salt and pepper to taste, 3 lumps of sugar, and cayenne.

Mode. Put the liquor, bones, onions, turnips, pepper and salt into a stewpan, and simmer for 3 hours. Scrape and cut the carrots thin, strain the soup on them, and stew them till soft enough to pulp through a hair sieve or coarse cloth; then boil the pulp with the soup, which should be of the consistency of pea soup. Add cayenne. Pulp only the red part of the carrot, and make this soup the day before it is wanted.

Time.—4⁄2 hours. Seasonable from October to March. Sufficient for 8 persons.

Soup, Celery. Ingredients.—9 heads of celery, 1 teaspoonful of salt, nutmeg to taste, 1 lump of sugar, ⁄2 pint of strong stock, a pint of cream, and 2 quarts of boiling water.

Mode.—Cut the celery into small pieces; throw it into the water, seasoned with the nutmeg, salt and sugar. Boil it till sufficiently tender; pass it through a sieve, add the stock and simmer it for half an hour. Now put in the cream, bring it to the boiling point, and serve immediately.

Time.—1 hour.

Soup, Giblet. Scald and carefully clean 3 or 4 sets of goose or duck giblets; let them stew well, a pound or two of gravy beef, scrag of mutton, or the bone of a knuckle of veal, an ox-tail, or some shanks of mutton, with 3 onions, a large bunch of sweet herbs, a teaspoonful of white pepper, and a large spoonful of salt. Add 5 pints of water and simmer till the gizzards (which must be each in four pieces) are quite tender; skim nicely, and add a ⁄4 pint of cream, 2 teaspoonfuls of mushroom powder, and 1 oz. of butter mixed with a dessert-spoonful of flour. Let it boil a few minutes, and serve with the giblets. Instead of cream, two glasses of sherry or Madeira, a large spoonful of ketchup, and some cayenne may be used for the seasoning. Add salt when the soup is in the tureen.

For the larger part of the above culinary preparations we are indebted to the excellent cooking manuals of Miss Acton and Mrs Beeton.

Soup, a Good Family. Ingredients.—Remains of a cold tongue, 2 lbs. of shin of beef, any cold pieces of meat or beef bones, 2 turnips, 2 carrots, 2 onions, 1 parsnip, 1 head of celery, 4 quarts of water, ⁄2 teacupful of rice, salt and pepper to taste.

Mode.—Put all the ingredients in a stewpan, and simmer gently for 4 hours, or until all the goodness is drawn from the meat. Strain off the soup and let it stand till cold. The kernels and soft part of the tongue must be saved. When the soup is wanted for use, skim off all the fat, put in the kernels and soft parts of the tongue, slice in a small quantity of fresh carrot, turnip, and onion; stew till the vegetables are tender, and serve with toasted bread.

Time.—5 hours. Seasonable at any time. Sufficient for 8 persons.

Soup, Gravy. Ingredients.—4 lbs. of shin of beef, a piece of the knuckle of veal weighing 4 lbs., a few pieces of trimmings of meat or poultry, 3 slices of nicely flavoured lean ham, ⁄4 lb. of butter, 2 onions, 4 carrots, 1 turnip, nearly a head of celery, 1 blade of mace, 6 cloves, a bunch of savoury herbs, seasoning of salt and pepper to taste, 3 lumps of sugar, 5 quarts of boiling soft water. It can be flavoured with ketchup, Leamington sauce, or Harvey’s sauce and a little soy.

Mode.—Slightly brown the meat and ham in the butter, but do not let them burn. When this done, pour to it the water, put in the salt, and as the scum rises take it off; when no more appears, add all the other ingredients, and let the soup simmer slowly by the fire for 6 hours without stirring it any more from the bottom; take it off, and pass it through a sieve. When perfectly cold and settled all the fat should be removed, leaving the sediment untouched, which serves nicely for thick gravies, hashes, &c. The flavourings should be added when the soup is heated for table.

Time.—7 hours. Seasonable all the year. Sufficient for 12 persons.

Soup, Green Pea. Ingredients.—3 pints of green peas, ⁄4 lb. of butter, 2 or 3 thin slices of ham, 4 onions sliced, 4 shredded lettuces, the crumb of 2 French rolls, 2 handfuls of spinach, 1 lump of sugar, 2 quarts of medium stock.

Mode.—Put the butter, ham, 1 quart of the peas, onions and lettuces, to a pint of stock and simmer for an hour; then add the remainder of the stock, with the crumb of the French rolls, and boil for another hour. Now boil the spinach, squeeze it very dry, and rub it, with the soup, through a sieve, to give the preparation a good colour. Have ready a pint of young peas boiled; add them to the soup, put in the sugar, give one boil, and serve.

Time.—2⁄2 hours. Seasonable from June to the end of August. Sufficient for six persons.

⁂ It will be well to add, if the peas are not quite young, a little more sugar; where economy is essential, water may be used instead of stock for this soup, boiling in it likewise the peashells, and using rather a larger quantity of vegetables.

Soup, Hare. Cut down a hare into joints, and put it into a soup-pot or large stewpan, with about a pound of lean ham, in thick slices, 3 moderately sized mild onions, 3 blades of mace, a faggot of thyme, sweet marjoram and parsley, with about 3 quarts of good beef stock. Let it stew very gently for full three hours from the time of its first beginning to boil, and more if the hare be old. Strain the soup, and pound together very fine, the slices of ham and all the flesh of the back, legs, and shoulders of the hare, and put this meat into a stewpan with the liquor, in which it was boiled, the crumb of two French rolls, and half a pint of port wine. Set it on the stove to simmer twenty minutes; then rub it through a sieve, place it again on the stove till very hot, but do not let it boil; season it with salt and cayenne, and send it to table directly.

Ingredients.—Hare, 1; ham, 12 to 16 oz.; onions, 3 to 6; mace, 3 blades; faggot of savoury herbs; beef stock, 3 quarts; 2 hours. Crumb of 2 rolls; port wine, ⁄2 pint; little salt and cayenne; 20 minutes.

Soup, Hare, a less Expensive. Pour on two pounds of neck or shin of beef, and a hare well washed and carved into joints, one gallon of cold water, and when it boils and has been thoroughly skimmed, add 1⁄2 oz. of salt, 2 onions, 1 large head of celery, 3 moderate-sized carrots, a tablespoonful black peppercorns, and 6 cloves.

Let these stew gently for 3 hours, or longer, should the hare not be perfectly tender. Then take up the principal joints, cut the meat from them, mince, and pound it to fine paste, with the crumb of 2 penny rolls (or 2 oz. of crumb of household bread), which has been soaked in a little of the boiling soup, and then pressed very dry in a cloth; strain, and mix smoothly with it the stock from the remainder of the hare; pass the soup through a strainer, season it with cayenne, and serve it when at the point of boiling; if not sufficiently thick, add to it a tablespoonful of arrow-root, moistened with a little broth, and let the soup simmer for an instant afterwards. Two or 3 glasses of port wine, and 2 dozen of small forcemeat balls may be added to this soup with good effect.

Ingredients.—Beef, 2 lbs.; hare, 1; water, 1 gall.; salt, 1⁄2 oz.; onions, 2; celery, 1 head; carrots, 3; bunch of savoury herbs; peppercorns, 1 teaspoonful; cloves, 6; 3 hours or more. Bread, 2 oz.; cayenne, arrow-root (if needed) 1 tablespoonful.

Soup, Haricot Bean. Take a quart of haricot beans and let them soak all night in cold water. Then pour on them 2⁄2 pints of cold water, add 1 onion, and put on the fire, and when the liquid begins to boil, let them continue to boil for 3 hours. Then remove from the fire and strain through a wire sieve, after which return to the saucepan, and season with pepper and salt; next add 2 oz. of butter and a little milk. Then just boil up, and serve. An economical and nutritious soup for the poor.

Soup, Julienne. Ingredients.—⁄2 pint carrots, ⁄2 pint of turnips, ⁄2 pint of onions, 2 or 3 leeks, ⁄2 head of celery, 1 lettuce, a little sorrel and chervil, if liked, 2 oz. butter, 2 quarts of medium stock.

Mode.—Cut the vegetables into strips about 1⁄4 in. long, and be particular they are all the same size, or some will be hard, whilst the others will be done to a pulp. Cut the lettuce, sorrel, and chervil into larger pieces; fry the carrots in the butter, and pour the stock boiling to them. When this is done, add all the other vegetables thereto, and stew gently for nearly an hour. Skim off all the fat, pour the soup over thin slices of bread cut round, about the size of a shilling, and serve.

Time.—1⁄2 hour. Seasonable all the year. Sufficient for 7 or 8 persons.

⁂ In summer, green peas, as asparagus tops, French beans, &c., can be added. When the vegetables are very strong, instead of frying them in butter at first, they should be blanched, and afterwards simmered in the stock.

Soup, Macaroni. Throw 4 oz. of fine, fresh, mellow Naples macaroni into a pan of fast-boiling water, with about 1 oz. of fresh butter, and a small onion stuck with 3 or 4 cloves (the onion must be omitted for white soups). When it has swelled to its full size, and become tender, drain it well, cut it into half-inch lengths, and slip it into a couple of quarts of clear gravy soup; let it simmer for a few minutes, when it will be ready for table. Observe that the macaroni should be boiled quite tender; but it should by no means be allowed to burst, nor to become pulpy. Serve grated Parmesan cheese with it.

Ingredients.—Macaroni, 4 oz.; butter, 1 oz.; 1 small onion; 5 cloves; ⁄4 hour, or more. In soup 5 to 10 minutes.

Soup, Mock Turtle. Ingredients.—Half a calf’s head, ⁄4 lb. butter, ⁄4 lb. lean ham, 2 tablespoonfuls of minced parsley, a little minced lemon thyme, sweet marjoram, basil, 2 onions, a few chopped mushrooms (when obtainable), 2 shalots, 2 tablespoonfuls of flour, 2 glasses of madeira or sherry, forcemeat balls, cayenne, salt and mace to taste, the juice of one lemon and 1 Seville orange, 1 dessert-spoonful of pounded sugar, 3 quarts of best strong stock.

Mode.—Scald the head with the skin on, remove the brain, tie the head up in a cloth, and let it boil for an hour. Then take the meat from the bones, cut it into small square pieces, and throw them into cold water. Now take the meat, put it into a stewpan, and cover it with stock; let it boil gently for an hour, or rather more, if not quite tender, and set it on one side. Melt the butter in another stewpan, and add the ham, cut small, with the herbs, parsley, onions, shalots, mushrooms, and nearly a pint of stock; let these simmer slowly, for 2 hours, and then dredge in as much flour as will dry up the butter. Fill up with the remainder of the stock, add the wine, let it stew gently for 10 minutes, rub it through a sieve, and put it to the calf’s head; season with cayenne, and, if required, a little salt; add the juice of the orange and lemon; and when liked, ⁄4 teaspoonful of pounded mace, and the sugar. Put in the forcemeat balls, simmer 5 minutes, and serve very hot.

Time.—4⁄2 hours. Seasonable in winter. Sufficient for 10 persons.

⁂ The bones of the head should be well stewed in the liquor it was first boiled in, and will make good white stock, flavoured with vegetables.

Soup, Ox-tail. A very inexpensive and nutritious soup may be made of ox-tails, but it will be insipid without the addition of a little ham, knuckle of bacon, or a pound or two of other meat.

Wash and soak 3 tails, pour on them a gallon of cold water, let them be brought gradually to boil, throw in 1⁄2 oz. of salt, and clear off the scum carefully as soon as it forms upon the surface; when it ceases to rise, add four moderate-sized carrots, from 2 to 4 onions, according to the taste, a large faggot of savoury herbs, a head of celery, a couple of turnips, 6 or 8 cloves, and ⁄2 a teaspoonful of peppercorns. Stew these gently from 3 to 3⁄2 hours, if the tails be very large; lift them out, strain the liquor, and skim off all the fat; divide the tails into joints, and put them into a couple of quarts or rather more of the stock; stir in when these begin to boil, a thickening of arrow-root or rice flour, mixed with as much cayenne and salt as may be required to flavour the soup well, and serve it very hot.

Ingredients.—Ox tails, 3; water, 1 gall.; salt 1⁄2 oz.; carrots, 4; onions, 2 to 4; turnips, 2; celery, 1 head; cloves, 8; peppercorns, ⁄2 teaspoonful; faggot of savoury herbs; 3 to 3⁄2 hours. For a richer soup, 5 to 6 hours.

Soup, Ordinary Pea. Wash well a quart of good split peas, and float off such as remain on the surface of the water; soak them for one night, and boil them with a bit of soda the size of a filbert, in just sufficient water to allow them to break to a mash. Put them into from 3 to 4 quarts of good beef broth, and stew them in it gently for an hour; then work the whole through a sieve, heat afresh as much as may be required for table, season it with salt, or cayenne, or common pepper, clear it perfectly from scum, and send it to table with fried or toasted bread. Celery sliced and stewed in it will be found a great improvement.

Ingredients.—Peas, 1 quart; soaked one night, boiled in 2 quarts or rather more of water, 2 to 2⁄2 hours. Beef broth, 3 to 4 quarts; 1 hour. Salt and cayenne or pepper, as needed; 3 minutes.

Soup, Portable. Syn. Glaze. From skin of beef, or other like part; the soup being gently simmered until reduced to the consistence of a thin syrup, and then poured into small upright jelly-pots, with covers, or, upon flat dishes, to lie about ⁄4 inch deep. The latter, when set, is divided into pieces, which are dried. Used to make extemporaneous soup and glazes. A similar article, prepared on the large scale, now generally forms part of every ship’s stores.

Soup, Potato. Mash to a smooth paste, 3 lbs. of good mealy potatoes, which have been steamed, or boiled very dry; mix with them, by degrees, 2 quarts of boiling broth, pass the soup through a strainer, set it again on the fire, add pepper and salt, and let it boil for five minutes. Take off entirely the black scum that will rise upon it, and serve it very hot, with fried or toasted bread. Where the flavour is approved, 2 oz. of onions minced and fried a light brown, may be added to the soup, and stewed in it for 10 minutes before it is sent to the table.

Ingredients.—Potatoes, 3 lbs.; broth, 2 quarts; 5 minutes. (With onions, 2 oz.) 10 minutes.

Soup, Spanish Onion. Peel two large Spanish onions and cut them into rings; fry them with a little dripping in a stewpan. When the onions have browned, add 2⁄2 pints of boiling water, and let them boil for two hours and a half; add pepper and salt to flavour, and a little vinegar. Thicken with oatmeal or bread crumbs (oatmeal is the more nourishing); let the mixture boil for another half hour, and serve. A good cheap wholesome soup.

Soup, Turnip, Cheap. Wash and wipe the turnips, pare and weigh them; allow 1⁄2 lb. for every quart of soup, cut them in slices about ⁄4 inch thick. Melt 4 oz. of butter in a clean stewpan, and put in the turnips before it begins to boil; stew them gently ⁄4 hour, taking care that they shall not brown, then have the proper quantity of soup ready boiling, pour it on them and let them simmer in it for ⁄4 hour. Pulp the whole through a coarse sieve or soup strainer, put it again on the fire, keep it stirred until it has boiled three or four minutes, take off the scum, add salt or pepper if required, and serve it very hot.

Ingredients.—Turnips, 3 lbs.; butter, 4 oz.; ⁄4 hour. Soup, 2 quarts; ⁄4 hour. Last time, 3 minutes.

Soup, Vermicelli. Drop very lightly and by degrees 6 oz. of vermicelli, broken rather small, into 3 quarts of boiling bouillon, or clear gravy soup; let it simmer for half an hour over a gentle fire, and stir it often.

Ingredients.—Bouillon or gravy soup, 3 quarts, vermicelli, 6 oz.; 30 minutes. Or soup, 3 quarts; vermicelli, 4 oz.; blanched in boiling water, 5 minutes; stewed in soup 10 to 15 minutes.

SOUR′ING. See Malt liquors and Wines.

SOY. Genuine soy is a species of thick black sauce, imported from China. Prep. Take of the seeds of Soja hispida (white haricots or kidney beans may be used for them), 1 gall.; boil them in water, q. s., until soft, add of bruised wheat, 1 gall., and keep the mixture in a warm place for 24 hours; then add of common salt, 1 gall.; water, 2 gall.; put the whole into a stone jar, and bung it up loosely for two or three months, shaking it very frequently during the whole time; lastly press out the liquor and bottle it; the residuum may be treated afresh with water and salt, for soy of an inferior quality.

Obs. The soy of the shops is, in nine cases out of ten, a spurious article made in this country, by simply saturating molasses or treacle with common salt. A better and a really wholesome imitation is made as follows:—Malt syrup, 1 gall. (or, 13⁄2 lbs.); treacle, 5 lbs.; salt, 4⁄4 lbs.; mushroom juice, 1 quart; mix, with a gentle heat, and stir until the union is complete; in a fortnight decant the clear portion.

SPAN′ISH FLIES. See Cantharides.

SPAR′ADRAP. Syn. Sparadrapum, L. Originally a cerecloth; now applied to spread plasters; as SPARADRAPUM COMMUNE, common strapping or adhesive plaster; S. VESICATORIUM, blistering plaster or tissue, &c.

The following are in occasional demand by the pharmacist:—

Sparadrap, Opium. Syn. Sparadrapum opii (M. Schœufelle.) Prep. On a piece of black sarcenet of a close and strong texture, properly stretched; spread with a brush, 3 layers of extract of opium, softened with water, to the consistence of treacle, and mixed with a sixth part of powdered gum. Keep the plaster dry.