Part 85

=BRONZE.= [Eng., Fr., Ger.] _Syn._ ÆS, L.; BRONZO, It. An alloy of tin and copper, remarkable for the exactness of the impressions which it takes by moulding and stamping, as well as for its great durability. It has hence been always extensively employed in the casting of buts, medals, statues, &c. In ancient times, when the manufacture of steel was ill-understood, cutting instruments were commonly made of it. It was also the general material of coins of small value; a use which, of late years, has been revived in several of the states of Europe, and still more recently in the coinage of these realms. Bell-metal, gun-metal, and speculum-metal are mere varieties of bronze.

_Prep._ On the small scale this alloy is prepared in crucibles; but for statues and larger works on reverberatory hearths. The fusion of the mixed metals is conducted as rapidly as possible under pounded charcoal, and the melted mass is frequently stirred together to produce a perfect mixture before casting.

The proportions of the materials so vary in different castings that it is almost impossible to say precisely what quantities are the best. The following are given as examples:--

_a._ For EDGE-TOOLS:--Copper, 100 parts; tin, 14 parts. When skilfully hardened and tempered this alloy is capable of receiving an edge nearly equal to that of steel.

_b._ For GILDING:--1. Copper, 82 parts; zinc, 18 parts; tin, 3 parts; lead, 2 parts.

2. From copper, 83 parts; zinc, 17 parts; tin, 2 parts; lead, 1 part.

_c._ For MEDALS:--1. Copper, 89 parts; tin, 8 parts; zinc, 3 parts. This alloy assumes a beautiful antique appearance by age, and takes a sharp impression by stamping.

2. (M. Chaudet.) Copper, 95 parts; tin, 4 or 5 parts. This is also excellent for any small castings.

_d._ For MORTARS:--Copper, 93 parts; lead, 5 parts; tin, 2 parts.

_e._ For STATUARY:--1. Copper, 88 parts; tin, 9 parts; zinc, 2 parts; lead, 1 part.

2. Copper, 82-1/2 parts; zinc, 10-1/2 parts; tin, 5 parts; lead, 2 parts. These are very nearly the proportions of the celebrated statue of Louis XV.

3. Copper, 90 parts; tin, 9 parts; lead, 1 part.

4. Copper, 91 parts; tin, 9 parts.

For a gold varnish for bronze objects refer to BRASS.

_Obs._ Several analyses have been made of ancient cutting instruments, from which it appears that the proportion of tin varies from 4% to 15%; a fact which tends to prove that more depends upon the exact mode of tempering the alloy than on the relative proportions of the ingredients. Lead and zinc are inadmissible in bronze for this purpose. One or two per cent. of iron may, nevertheless, be added with advantage. The ancient bronze used for springs contained only 3% to 4% of tin. The edges and lips of bronze mortars must be carefully tempered by heating them to a cherry red, and then plunging them into cold water, as unless so treated they are very apt to be broken in use. See BELL-METAL, BRASS, GUN-METAL, &c.

=Bronze'-powder.= _Syn._ BRONZE. A name given to various powders having a rich metallic appearance, which they retain when applied on varnish, or when mixed with it, as in surface bronzing.

_Prep._ 1. GOLD-COLOURED:--_a._ From Dutch-foil, reduced to an impalpable power by grinding. Cheap and looks well, and is very durable when varnished.

_b._ From gold-leaf, as the last.

_c._ Precipitated powder of gold.

_d._ From verdigris, 8 oz.; tutty powder, 4 oz.; borax and nitre, of each 2 oz.; bichloride of mercury, 1/4 oz.; grind them together, make the mixture into a paste with oil, and then fuse it; when cold, roll it into thin sheets or leaves, and grind it as in No. 1.

2. IRON-COLOURED:--Plumbago, in fine powder.

3. RED:--Sulphate of copper, 100 parts; carbonate of soda, 60 parts; mix, and apply heat until they unite into a mass; then cool, powder, and add of copper filings, 15 parts; again well mix, and keep the compound at a white heat for about twenty minutes; lastly, when cold, reduce the 'residuum' to an impalpable powder, wash it in pure water, and dry it.

4. SILVER:--Bismuth and tin, of each 1 oz.; melt them together, and add of quicksilver, 1 to 1-1/2 oz.; when cold, powder it.

_Obs._ The above are used by painters, japanners, &c. See BISULPHIDE OF TIN (TIN), POWDERS, &c.

=BRONZ'ING.= The process of giving a bronze-like, or an antique metal appearance, to the surface of copper, brass, and other metals. The following methods are recommended for this purpose:--

1. To the surface of the article, first thoroughly cleaned and polished, evenly apply with a brush the common crocus powder ('jewellers' rouge'), previously made into a smooth paste with water. When dry, place it in an iron ladle, or on a common fire-shovel, and expose it over a clear fire for about one minute; lastly, when sufficiently cold, polish it with a plate-brush. This gives a very rich appearance, similar to that on tea-urns; the shade depending on the duration and the degree of heat employed.

2. As the last, but substituting finely powdered plumbago for crocus powder. Equally beautiful, but deeper coloured and more permanent than that produced by No. 1.

3. As the preceding, but employing mixtures of plumbago and crocus in various proportions according to the shade desired.

4. A dilute solution of liver of sulphur (sulphurated potash), or of hydrosulphate of ammonia is applied with a camel-hair pencil to the metal previously slightly warmed; when dry, the surface is either left rough or brushed off. If liver of sulphur has been used, it will be better to wash it first in clean hot water; but without the slightest friction. This gives the appearance of very antique bronze.

5. Verdigris, 2 oz.; and sal-ammoniac, 1 oz.; are dissolved in vinegar, 1 pint; and the mixture is diluted with water until it tastes only slightly metallic, when it is boiled for a few minutes, and filtered for use. Copper medals, &c. (thoroughly clean) are steeped in the liquor at the boiling-point until the desired effect is produced. Care must be taken not to keep them in it too long. When taken out they are carefully washed in hot water, and dried. Effect as the last.

6. Verdigris and vermilion, of each 2 oz.; alum and sal-ammonia, of each 5 oz. (all in fine powder); vinegar, q. s. to form a thin paste. This is spread over the surface of the copper, which is then uniformly warmed by the fire, and afterwards well washed and dried. The tint may be deepened by repeating the process. The addition of a little blue vitriol inclines the colour to a chestnut-brown; and a little borax to a yellowish-brown. Used by the Chinese for copper tea-urns, &c.

7. Sal-ammonia, 1 oz.; cream of tartar, 3 oz.; common salt, 3 oz.; hot water, 1 pint; dissolve; then add of nitrate of copper, 2 oz., dissolved in 1/2 a pint of water; mix well, and with it repeatedly moisten the article (placed in a damp situation) by means of a soft brush. Produces a very antique appearance.

8. Salt of sorrel, 1 oz.; sal-ammoniac, 3 oz.; distilled vinegar, 1 quart; dissolve. As the last. Much used for bronze figures.

9. A very weak solution of bichloride of platinum, applied with a hair pencil or by immersion. Used for binding screws, holders, and other small articles of copper and brass.

10. Sulphate of iron and sulphate of copper, of each 1 oz.; water, 1 pint; dissolve; wash the surface of the articles with it; let them dry; then apply a solution of verdigris, 2 oz. dissolved in strong vinegar, 1/4 pint; when dry, polish them with a soft brush, and either some plumbago or colcothar. Used for tin castings.

11. The articles (properly cleaned) are either immersed in, or washed over, with a solution of sulphate of copper or of verdigris. In a short time they acquire a coating of pure metallic copper, and are then washed. This only answers with iron and steel goods. It is admirably suited for iron castings.

12. An antique appearance may be given to silver by either exposing it to the fumes of hydrosulphate of ammonia, or immersing it for a very short time in a solution of hydrosulphate of ammonia, or in dilute nitric acid.

=Bronzing, Sur'face.= A term commonly applied to the process of imparting a bronze-like or metallic appearance to the prominent portions of the surfaces of figures made of paper, wood, plaster of Paris, &c. It is effected by first giving them a coat of oil-varnish or size, and when this is nearly dried, applying, with a 'dabber' of cotton, or a camel-hair pencil, any of the ordinary metallic bronze-powders before referred to. Sometimes the powder is placed in a little bag of muslin, and dusted over the surface. The articles should be afterwards varnished.

Paper is bronzed by mixing the bronze-powders up with a little weak gum-water, and burnishing the surface when dry and hard.

=Electrotypes, to Bronze. Green.= Steep the medal or figure in a strong solution of common salt, or sugar, or sal-ammoniac, for a few days; wash in water, and allow to dry slowly; or suspend it over a vessel containing a small quantity of bleaching powder, and cover over. The length of time it is allowed to remain will determine the depth of colour.

=Brown.= Add four or five drops of nitric acid to a wine-glassful of water. The object is rubbed over with this gently, and allowed to dry, and when dry subjected to a gradual and equal heat; the surface will be darkened in proportion to the heat applied.

=Black.= Wash the surface over with a little dilute solution of hydrosulphate of ammonia, and dry at a gentle heat.

=BROOM.= The common name of the plant _spar'tium scopa''rium_. A useful diuretic; of great service in dropsy. See DECOCTION.

=Broom Ashes.= From broom-stalks burnt. Formerly used as a diuretic in dropsy.

=Broom, Salt of.= Obtained by dissolving broom ashes in water, and filtering and evaporating the solution. It consists principally of carbonate of potassa. It was formerly used in dropsy, and as an antacid, &c.

=BROSSÉ DE CORAIL.= [Fr.] The root of lucerne (_medicago sativa_), cleaned, dried, and hammered at the end. Used as a tooth-brush.

=BROTH.= _Syn._ JUS (coctis carnibus), JUS'CULUM, L.; BOUILLON, JUS, Fr.; FLEISCHBRÜHE, Ger. In _cookery_, the liquor in which flesh has been boiled. Broth is distinguished from soup by its inferior strength and quantity of seasoning, &c. It contains much of the nutriment of the meat. We extract the following from Dr Letheby's work 'On Food':--

"A nutritious broth, containing the albumen of the meat or chicken, may be obtained by infusing a third of a pound of minced meat or chicken in 14 oz. of _cold_ water, to which a few drops (4 or 5) of muriatic acid and a little salt (from 10 to 18 grains) have been added. After digesting for an hour or so, it should be strained through a sieve, and the residue washed with five ounces of water, and pressed, The mixed liquids thus obtained will furnish about a pint of _cold extract of meat_, containing the whole of the soluble constituents of the meat (albumen, creatin, creatinin, &c.), and it may be drunk cold, or slightly warmed, the temperature not being raised above 100° F., for fear of coagulating the albumen."

=Broth, Scotch.= This, which is in very general use amongst the middle and working classes of Scotland, is made as follows:--Put into a pot three quarts of cold water along with a cupful of Scotch barley, and let it boil; add two pounds of neck of mutton. Allow it to stew gently for an hour, skimming occasionally. Then add turnips cut in squares, and onions sliced, and carrots and turnips uncut. The half of a small cabbage chopped in moderately fine pieces may be put in instead of all these vegetables; and leeks may be used instead of onions. Stew the whole for an hour longer. The broth is now ready. Season with salt and serve in a tureen. The meat is served in a separate dish, with the uncut pieces of turnip and carrot and a little of the broth as gravy. Any meat may be employed in the same way. Broths and soups contain the greater part of the saline matter of the meat, the crystalline principles, viz. creatin and creatinin, some of the albumen and fat, and an amount of gelatin, dependent upon the duration of the boiling process. They also contain nearly all the odorous matters of the meat. Cold water extracts from one sixth to one fourth of the solid ingredients of meat. The presence of a large quantity of highly nitrogenous crystalline principles in broths and soups accounts for their restorative powers. These, which are the _creatin_ and _creatinin_, bear a close resemblance to the thein of tea and coffee, and the _theobrominæ_ of cocoa, in their physiological effects.

Broth is contra-indicated for children at the breast, as it not unfrequently induces sickness, disorders the bowels, and induces fever. The same applies to beef tea. When, however, broth and beef tea are used as clysters in such quantities that can be retained, they act most beneficially. See BOILING, SOUP, &c.

=BROWN DYE.= Every shade of brown may be produced, almost at will, by mixtures of reds and yellows with blues and blacks; or directly by simple dyes. The following are examples:--

_a._ For COTTON:--

1. Give the goods a mixed mordant of acetate of alumina and acetate of iron, followed by a bath of madder or of madder and fustic. Excess of acetate of alumina turns it on the AMARANTH TINT; the acetate of iron darkens it.

2. First 'gall' the goods, then turn them for a short time through the black bath; next give them a mordant of sulphate of copper, then pass them through a decoction of fustic, afterwards through a bath of madder, and again through the solution of sulphate of copper; drain, dry, rinse well, and finish with a boil in soap and water. This gives a CHESTNUT-BROWN.

3. First give the goods a mordant of alum, then a bath of madder, and next a bath of fustic to which a little green copperas has been added. This gives a CINNAMON-BROWN.

_b._ For LINEN:--This varies little from that commonly employed for cotton.

_c._ For SILK:--

1. One of the above mordants is followed by a bath made by mixing equal parts of the decoctions of logwood, fustic, and Brazil-wood. The shade may be varied by altering the proportions of the decoctions; Brazil-wood reddening, logwood darkening, and fustic yellowing, the tint.

2. Annotta, 4 oz.; and pearlash, 1 lb.; are dissolved in boiling water, q. s.; the silk is passed through it for two hours, then taken out, and squeezed dry; it is next passed through a mordant of alum, and then through a bath of Brazil-wood, followed by another of logwood to which a little green copperas has been added.

_d._ For WOOL:--

1. Boil the cloth in a mixed mordant of alum, common salt, and water, then dye it in a bath of logwood to which a little green copperas has been added. 2 oz. of alum, and 1 oz. of salt, are required for every lb. of wool.

2. Boil the goods in a mordant of alum and sulphate of iron, then pass them through a bath of madder. The more copperas the darker will be the dye. Good proportions are 2 parts of alum and 3 of copperas.

3. Give a mordant of alum and tartar, then pass the goods through a madder bath; next run them through a bath of galls and sumach or logwood to which a little acetate or sulphate of iron has been added.

4. Mordant the cloth as last, dye in a madder bath, remove the cloth, add a little acetate or sulphate of iron, and again pass it through the bath as long as necessary.

5. Give the cloth a light blue ground with indigo, and then a mordant of alum; rinse, and lastly run it through a bath of madder.

6. A mordant of alum and tartar, followed by, first a bath of madder, and afterwards a bath of weld or fustic to which a little iron-liquor has been previously added. In this way every shade, from MORDORÉ and CINNAMON to DARK CHESTNUT, may be produced.

7. Boil fustic-chips, 1 lb., for 2 hours; pass the cloth through the bath for 1 hour; take it out and drain; add of green copperas, 1-1/4 oz.; good madder, 4 oz.; boil for a short time, and again pass the cloth through the bath, until it acquires the proper tint. BRONZE-BROWNS, and every similar shade, may be thus given by varying the proportions.

_e._ The following are called SUB'STANTIVE or DIRECT BROWNS:--

1. Decoction of oak-bark. It dyes wool of a fast brown of various shades, according to the quantity employed. A mordant of alum brightens it.

2. Infusion or decoction of walnut-peels. Dyes wool and silk a brown, which is brightened by alum.

3. Horse-chestnut-peels. A mordant of chloride of tin turns it on the BRONZE; and sugar of lead, on the REDDISH-BROWN.

4. Catechu or Terra Japonica. For cottons. Blue vitriol turns it on the BRONZE, and green copperas darkens it, when applied as mordants. Acetate of alumina as a mordant brightens it. The French colour, CARMELITE, is given with 1 lb. of catechu, 4 oz. of verdigris, and 5 oz. of sal-ammoniac.

5. Sulphate or chloride of manganese. Dissolved in water with a little tartaric acid, it gives the bronze tint called SOLITAIRE. The stuff, after being passed through the solution, is turned through a weak lye of potash, and afterwards through another of chloride of lime, to heighten and fix it.

6. Prussiate of copper. This gives a fine BRONZE or YELLOWISH-BROWN to silk. A mordant of blue vitriol is commonly first given, followed by a bath of prussiate of potash.

=BROWN PIG'MENTS.= The principal and most useful of these are--umber, terra di Sienna (both burnt and raw), Spanish brown, and some of the ochres. Brown, of almost any shade, may be made by the admixture of blacks with reds and yellows, or with greens, in different proportions. See BISTRE, BLACK, NEWCASTLE,[233] OCHRES, SEPIA, &c.

[Footnote 233: Under BLACK PIGMENTS.]

=Brown, Span'ish.= See OCHRES.

=BROWN PINK.= See YELLOW PIGMENTS.

=BROWN'ING.= In _cookery_, a fluid preparation used to colour and flavour gravies, soups, &c.

_Prep._ 1. Sugar, 4 oz.; and butter, 1 oz.; are melted in a frying-pan or ladle with about a tablespoonful of water, and the heat is continued until the whole has turned of a deep brown; the heat is then lowered a little, and some port wine (about 1 pint) is gradually poured in; the pan is now removed from the fire, and the mixture well stirred until the roasted sugar is entirely dissolved; it is then put into a bottle, and 1/2 oz. each of bruised pimento and black pepper, 5 or 6 shalots (cut small), a little mace and finely grated lemon peel, and 1/4 pint of mushroom catsup, added. The bottle is shaken daily for a week, and the clear liquid, after 5 or 6 days' repose, decanted into another bottle. Rich flavoured, but expensive.

2. As the last, but using strong beer, or water, instead of wine. A glassful of spirit may be added after bottling it.

3. Sugar-colouring, 1 pint; salt, 1/4 lb.; mushroom-catsup, 1/2 pint; spice, q. s. Excellent for all ordinary purposes.

4. Lump sugar (powdered), 2-1/2 lbs.; salad oil, 1/2 lb.; heat as before; then add, of port wine, 1 quart; Cape wine, 3 quarts; shalots, 6 oz.; mixed spice, 4 oz.; black pepper, 3 oz.; mace, 1 oz; salt, 1 lb.; lemon juice, 1 pint; catsup, 1 quart; mix well.

5. Good spirit-colouring or sugar-colouring and mushroom catsup, of each 1 gall.; Jamaica pepper, black pepper, and shalots, of each 4 oz; cloves, cassia, and mace, bruised, of each 3/4 oz.; boil in a covered vessel for 5 minutes; digest for 14 days, and strain.

6. Colouring, 3 pints; mushroom catsup, 1 pint; common salt, 3/4 lb.; Chili vinegar (strongest), 1/2 pint; spice, q. s. Half a pint of British brandy or rum may be added.

_Obs._ The above are excellent additions to gravies, soups, &c.; and of themselves form most admirable sauces for fish, meat, and game.

=Browning= (for Gun-barrels). _Prep._ The following are current formulæ:--

1. Blue vitriol, 4 oz.; tincture of chloride of iron, 2 oz.; water, 1 quart; dissolve, and add aquafortis and sweet spirit of nitre, of each 1 oz.

2. Blue vitriol and sweet spirit of nitre, of each 1 oz.; aquafortis, 1/2 oz.; water, 1 pint; as last.

3. Butter of antimony and sweet oil, equal parts; well shaken together. To be applied to the iron previously warmed.

_Obs._ The above fluids are rubbed on the barrel (previously well polished and cleaned off with whiting to remove the oil), and allowed to remain on for some hours, or until the next day, when they are rubbed off with a stiff brush. The process may be repeated, if necessary. The barrel is next washed in water in which a little pearlash or soda has been dissolved, and afterwards well rinsed in clean water; it is then polished, either with the burnisher, or with a brush and beeswax. Sometimes a coat of tough shell-lac varnish is applied.

=BRUCEA= (-sh'[)a]). False cusparia (which _see_).

=BRUCHBALSAM--RUPTURE BALSAM= (Dr Tänzer).--No. 1. Compound rosemary cerate, nutmeg cerate, red Johannis oil, yellow wax, of each 1 part; fat, 5 parts. No. 2. Mixture of nutmeg cerate, 50 parts; tallow, butter, of each 10 parts, melted and mixed with 25 parts strongest liquor potassæ. No. 3. Compound rosemary cerate, oil of bayberries, of each 2 parts; nutmeg cerate, 4 parts; red Johannis oil, 6 parts; yellow wax, 3 parts; tincture of myrrh and tincture of aloes, of each 1/2 part; tr. opii, 1/4 part, melted and heated until the spirit has evaporated. (Hager.)

=BRUCHPFLASTER--RUPTURE PLASTER= (Krüsi Altherr). A spread plaster, the mass consisting of 5 parts Bergundy pitch and 2 parts turpentine. (Walz and Hager.)

=Bruchpflaster--Rupture Plaster= (Caspar Menet). Machine-made paper covered with thin gauze, and thinly spread with a mass of 9 parts wax, 3 parts turpentine, and 1 part elemi. (Hager.)

=BRUCHSALBE--RUPTURE CERATE= (Gottlieb Sturzenegger, Herisau, Canton Appenzell). A mixture of 50 parts fat and 1 part oil of bayberries. (Hager.)

=BRUCHE=, ruptures cured without medicine, operation, or pain, by Lavedan, chemist. A pelotte containing in it zinc and copper plate on which a solution of the "poudre electrochimique" (common salt) is dropped. (Hager.)

=BRU'CIA.= C_{23}H_{26}N_{2}O_{4}. Aq. [Eng., Fr.] _Syn._ BRU'CINE; BRU'CINA, L. An alkaloid discovered by Pelletier and Caventou, in the bark of _bru'cia antidysenter'ica_, and afterwards associated with strychnia, in _nux vomica_.

_Prep._ Ground nux vomica, or the bark of brucia antidysenterica, is boiled in dilute sulphuric acid, and the resulting decoction mixed with hydrate of lime (in excess); the crude precipitate thus obtained is boiled in alcohol (sp. gr. ·850), and the tincture filtered whilst hot. A mixture of crude strychnia and brucia is deposited as the fluid cools, and the remainder is obtained by evaporation. This is powdered and digested in cold alcohol, which dissolves out the brucia; the solution furnishes crystals on spontaneous evaporation. It may be further purified by recrystallisation from alcohol.

_Prop._ Soluble in 850 parts of cold, and about 500 parts of hot water; freely soluble in alcohol; added to the dilute acids until they are neutralised, it forms crystallisable salts, easily obtained by evaporation.

_Tests._ It is distinguished from strychnia, which in many respects it resembles, by its ready solubility in both dilute and absolute alcohol, and its insolubility in ether. With nitric acid it strikes a fine red colour, which is removed by sulphuretted hydrogen and sulphurous acid. Iodic acid, chloric acid, and chlorine, also turn it red.