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at the same time, it should be so tough as not to crack, and should harden in a few hours if the ornament be thin, or in a day or two if it be more massive. The state in which it is used by the ornament maker is that of a stiff dough; and the making of it I'esembles the process by which the baker makes his dough. The proper amount of glue is steeped in water, which is heated to dissolve the glue; while the oil and rosin are melted in a separate vessel, and then poured into the vessel containing the melted glue. The whiting is pounded, and placed in a tub or pan—being previously warmed if the weather be damp and cold — and the hot melted glue, oil, and rosin is poured upon the whiting, and then well mixed up with it, and kneaded, rolled, and beat, until it becomes a smooth, tough, elastic kind of dough or putty. It may then either be used at once, or may be laid aside for future use; but, whenever it is used, it must be warmed, either before a fire or by admitting steam to act upon it, because, when cold, it is too hard and stiff for use.

Moulding.—The manner of using this composition is to press it into moulds; the preparation of which is the most important part of the business: it is generally done by men who are not engaged in making the ornaments themselves. The moulds are usually made of boxwood, which, by its smoothness of grain, admits very fine figures to be cut in it, and is very durable. The mould carver has to proceed with his work in an opposite way to the ordinary carver; for he must make depressions or hollows instead of raised projections, and projections instead of hollows. The mould carver makes his mould look, in every part, directly the reverse of what he wishes the ornament to appear.

Carved Moulds.—The block of wood being planed and smoothed, the carver draws on its surface a representation of the object which he wishes to carve, and then proceeds to work out the minute details. The tools used in this carving are exceedingly fine and sharp, some of them not exceeding one-twentieth of an inch in width. These are, as in com

mon carving, mostly gouges, with various degrees of curvature. The sharpening of them is a matter of great nicety, and in some cases requires files made o( very fine wire. The block of boxwood is moistened with oil during the process of cutting, in order to facilitate the progress of the tool. The cuts are, in the first instance, made perpendicularly from the surface of the wood, and afterwards varied into the necessary directions to produce the pattern. In order to know how to vary the depth of different parts of the mould, the carver must either be guided by the accuracy of his eye ami the correctness of his taste, or he mu^t have another mould of the same pattern before him.

Cast Moulds.—Sometimes moulds are made by casting, the material being brass, copper, pewter, lead, or sulphur. A model, representing the object which it is desired to produce, is made of composition or plaster, and is placed on a flat stone, and surrounded by a raised border or edging, so that it lies in a cell or trough. The model is then oiled, and the melted metal or sulphur is poured on it, so as to entirely cover it. When cold, the raised border is broken away, the mould taken up, and the model removed from within it. It is then imbedded in a wooden case to preserve it from injury, and to fit it for the better reception of the composition. Sometimes brass moulds are made in this way, and afterwards chased; that is, the minuter details of ornament are cut, or rather scratched, by very fine tools. When the mould, whether of wood, metal, or sulphur, is to be employed to cast ornaments, it is brushed over with oil, to prevent the adhesion of the composition. A piece of composition, large enough for the intended purpose, is then taken up in a warm soft state, and pressed into the mould by the hand. A wet board is laid upon the surface oi the composition, and the whole is put into a powerful screw-press, by which the composition is pressed into every part of the mould, however deep and minute it may be The same pressure makes the upper surface of the composition adhere to the wetted board, so that, when it is taken out of the press, the mould may be pulled off the ornament, leaving the latter adhering to the board. When the cast has become a little hardened, it is cut, or rather sliced off. with a broad knife, to the required thickness. Fixing.—The composition ornament, thus made, is exceedingly pliant and supple, and may be bent into almost any form without breaking or injuring it: it is this property which makes these ornaments so convenient; as they may be applied to the round, the flat, or the hollow parts of a frame, with almost equal ease. They are fixed on either with glue, or, if quite soft and warm, with hot water, which, by softening the glue contained in the composition, produces a sufficiently strong cement; and, in a short time, they become sufficiently firm and hard to be handled without injury. In modern frames which are intended to imitate antique carved frames, the manner of laying on the various pieces of ornament requires much care in the workman. If an antique frame, or a drawing from it, is given to the ornament maker to imitate, he must have moulds carved of all the various parts, so that, when united on the frame, the assemblage of composition casts may present a facsimile of the frame. If he wishes to produce a frame which shall possess a general resemblance to old patterns, but without tying himself down to any individual pattern, he has to depend on his taste and judgment, both in the cutting of moulds and in the disposition of the various pieces of ornament on a frame. This composition, beiug a compact substance, is heavy. In this point carved ornaments have a great superiority over composition; indeed, the heaviness of the latter was one reason which led to the adoption of papier-mache ornaments. When papiermache ornaments are used, they are cast in moulds, resembling those just described. The paper is in the state of a pulp; b;it there is this difference between the two kinds of ornaments. The pulp is pressed between two moulds, so that the th ckness of the ornaments is

seldom more than about a quarter of an inch at any part; thus the ornament is of less weight, and there is a saving of material.

To Hake a Thermometer.— Take a fine glass tube blown into a bulb at one end. The bulb is heated, the air expands; it is then placed under mercury, which rushes in as the tube cools, and takes the place of the air which was driven out by the heat. It is then managed so that the mercury should be at a convenient spot at the common temperature. Apply heat to the mercury until the column rises quite to the top of the tube; then seal it by applying heat, the mercury on cooling leaves a vacuum, which is essential to the perfection of the instrument. The great point is to graduate it. The freezingpoint of water or the melting-point of ice is always constant; the boiling-point of water is also con.tant. The barometric pressure being constant, distilled water is made to boil, and the thermometer surrounded with the steam produced; the point to which the mercury rises is marked off with a file, and the freezing-point of water is also marked. It only remains to divide the interval into degrees, which is arbitrary. In England Fahrenheit is used, the space between freezing and boiling being divided into 180, 32 being the freezing, and 212 the boiling-point. Zero is 32° below freezing point. In the Centigrade the interval is divided into 100. Zero is the freezing-point, and 100° the boiling-point. In Reaumur's scale the interval is divided into 80. Zero is again the freezicg-point, whilst 80° is the boiling-point. To change Centigrade into Fahrenheit, multiply by 9, divide by 5, and add 32. To change Fahrenheit into Centigrade, subtract 32, multiply by 5, and divide by 9. To. convert the degrees of Reaumur into Fahrenheit, multiply those of Reaumur by 9, divide by 4, and add 32; the sum will be the degrees on the scale of Fahrenheit. Spirit thermometers are the best where great cold is required, inasmuch as they are difficult to freeze. Mercury is best for high temperatures.

INDEX.

Acetate or Copfkb, 235.

of lead, 235.

Acetic acid, 235.
Aceto-nitrate bath, 283.
Acid-proof cement, 22.

, tannic, 326.

Ageing liquor, 40.
Alabaster, cleaning, 27
Alcohol barrels, 16.
Alkali testing, 374.
Albumen, 284.

iodized, 283.

Albumenized paper, 255.
Alloy for bells of clocks, 12.

cymbals and gongs, 12,

journal boxes, 12.

tam-tams, 12.

Alloys, 9-14.

fusible, 12.

Almond soap, 384.
Aluminium bronze, 13.
Alum white, pigment, 93.
Amalgamating salt, 244.

gilding by, 307.

Amalgam, gilding copper by, 311.

gold, 238, 307.

Amber, to dye silk, 32.

to dye woollen, 35.

to mend, 14.

——to work, 14.

varnish, 67.

Ammonia, 238.
Aniline colours, 33.
Animal fats, 373.
Annealing glass, 57.

steel, 338.

Anodes, 246.
Antimonial soap, 3S5.
Antimony deposits. 221.
Anti-fricuon grease, 333.

metal, Belgian, 334.

Anti-rast varnish, 359.

Apparatus, impervious cement for, 24.

Aquatortis, 13.

Aqua regia, 14.

Aquariums, cement for, 22.

Architectural cement. 25.

Argent*>meter, 250.

Armenian or jeweller's cement, 22.

Arsenic, flux for, 349.

Artificial gold, 11.

. grindstone, 403.

— gums, 340.

— ivory, 371

light, photography by, 287.

mother-of-pearl buttons. 339.

Ashes, treatment of electro waste 223.
Ash, soda, 374.
Ash vat, 38.
Asphalte varnish, 66.
Attrition metal, Babbitt's, 9.
Autogenous soldering, 367.
Awnings, waterproofing. 368.
Axles, lubricating composition for, 334.
Azure blue, 96.

Babbitt's Attrition Metal, 9.

Background in photography, 290.

Backing positives, varnish for, 72.

Balsam of sulphur, 52.

Band-saws, brazing and resetting, 3C6.

Bark decoction, tanning by, 322.

Barometer scales, silvering for. 318.

Baths and silver solutions, reducing old, 290.

Baths for magic-lantern slides, 288.

Bedsteads, red stain for, 418.

Beech, to stain mahogany colour, 417.

Beef tallow, 373.

Bell metal, 12.

Bells of clocks, alloy for, 12.

Belts. driving, 328.

Bending glass tubes, 60.

Benzine, 243.

Best Britannia, for handles, 11.

for lamps, pillars, and i-pouts, 11

for spoons, 11.

for spouts, 11,

Best red brass, 10.
Bicarbonate of potash, 239.
Bichloride of platinum, 240.
Bird-skins, preservative for, 333.
Bird's-eye maple, graining, 422.

carriage, graining, 83.

ground, 419.

Birds, to skin and stuff, 330.
Blshulphide of carbon, 246.
Bisulphite of soda, 245.
Bitartrate of potash, 239.
Black brasswork for instruments, 19.

bronze for brass, 19.

cotton. to dye, 36.

enamels, 48.

flux, 349.

Geneva, to dye woollen, 34.

house painting, 105, 109. japan, 67.

Jet, to dye woollen, 33.

— ivory, 97.

leather varnish, 69.

liquor, 40.

marble on wood, 425. pigments, 97.

Black pigment, blue, 98.

, reviver, 16.

solder, 366.

stain for wood, 418.

to dye silk. 30.

Slacking for harness, 328.

liquid, 16.

paste, 16.

Blanched copper, 10.
Blackboard, black for. 409.
Hleaching-house, arrangement of, wax, 354.
Bleaching ivory, 15, 370.

palm-oil, 372.

paper, 14, 429.

powder, 15.

prints, and printed books, 15.

silk, 14.

— sponge, 16.

wax, 342, 354.

WOOl, 14.

IMister removing from veneer, 413.
Blisters in photography, 280.
Blue, azure, 96.
Blue-black, 16.

— ink, 343.

pigment, 98.

calx, 52.

cobalt, 97.

enamels, 48.

. . house paint, 105.

ink. 345.

lake. pigment, 92.

to dye cotton, 37.

silk, 31.

— woollen, 34.

pictures. 291.

—— pigments, 96.

Prussian, 97.

. royal, to dye silk, 31.

woollen, 34.

Saxon, 97.

soluble, 16.

royal, 38.

— vat, 39.

woollen spirit, 40.

Bo'.ler incrustation, 16.
Boiling soap, 377.
Bone fat, 373.

polishing, 89.

Bones, glue from, 341.
Bookbinders' paste, 41.
—— varnish, 71.
Bookbinding, 394-401.

without tools. 398.

Book-edges, burnishing, 409.

marbling, 399-401.

Books, gilding and finishing, 309.
Boot and shoe making, 329.
Boot-top liquid, 328.

Boots, varnish for, 328.
Botany Bay wood, to imitate, 418.
Bottle corks, cement for, 22.
Bougies, parlour, 359.

transparent, 358.

Bouquet soap, 384.

Brass articles, to bronze, 18.

—— bath, arrangement of, 186.

correcting, 185.

for steel, iron, and tin, 185.

Brass, bath for zinc, 185.

solutions for, 184.

brightening and colouring, If.

common, for castings, 10.

deposits, 183.

colour of, 186.

for turning, 10.

bard, for casting, 10.

— lacquer for, 75.

melting, 1C.

plating, 186.

polishing, 402.

red, 10.

rolled, 10. «

silvering, 317.

solder for, 366.

solder for iron, 366.

to clean, 28.

to prepare for lacquering, 74.

to tin, 336.

wires, tinning, 337.

yellow, 10.

Brass-work for instruments, black, 13

re-lacquering, 74.

Brassing lead or pewter, 186.

Brazil-wood lake, pigment, 92.

Brazing saws, 366.

Bremen green, 94.

Brightening and colouring brass. 16.

tarnished jewellery, 319.

Britannia metal, 10.

for casting, 10.

for registers, 10.

— for spinning, 10.

hardening for, 10.

silver plating, 214.

Britannia ware, solder for, 364.
Bronze, antique, 235.

black, 235.

for brass, black, 19.

for cutting instruments, IT.

. for medals, 17.

—— for ornaments, 17.

for statuary, 17.

gold, 51.

green, 19.

liquid, 17.

metal, 11.

powders, 17

silver, 18.

Bronzing copper utensils, 19.

electrotypes, 20.

gas fittings, 18.

gold powder for, 18.

gold size, 306.

inlaid work, 418.

iron, 19.

paper, 18.

plaster, 18.

small brass articles, 18.

wood, 18.

Brown, cinnamon, to dye woollen, 34

dark, to dye woollen, 34.

cotton, to dye, 36.

enamel, 49.

— French, to dye woollen. 34.
— hard spirit varnish, 70. house paint, 105.

— olive, to dye woollen, 31.

Brown, stain for wood, 418.

to dye cotton, 36.

to dye cotton madder, 36.

Browning gun barrels, 21.
Brunswick black, 67.
— green, 94.
Brushes, hair for, 411.

varnish, 73.

Buff-colour house paint, 108.
Buff leather, cleaning, 329.

to dye cotton, 38.

silk, 32.

woollen, 35.

Bullet metal. 13.

Bullocks' horns, polishing, 407.

Burning lead. 361.

Burnish gold, 49.

Burnishing, 216, 407-109.

Burnishers, 407.

Burnished gilding, 298.

on glass, 300.

gilt frames, 304.

Cabinet Portraits, 295.

varnish, 64.

work, polish for, 87.

Calculating length of camera, 2SS.
Calf-skins, to ton, 322.
Calx, blue, 52.
Camera, copying, 287.

solar, 288.

stereoscopic views, 287.

twin lens, 286.

Cameos, to carve, 21.
Camphor savonette, 386.
Candles, 350.
Cauls, veneering, 411.
Carbon prints, colouring, 279.

oil-colours, 280.

retouching, 280.

water-colours on, 2S0.

Cardboard, transferring photographs to, 277
Cardwork, to varnish. 68.
Carminated lake, 92.
Carmine, 91.
Carriage graining, 83.

bird's-eye maple, 83.

curled maple, 84.

pollard oak, 83.

Carriage Japan, 79f 83.

painting, 79.

colouring, 80.

green colours, 82.

— Ironwork, 80.

lake colours, 82.

priming, 80.

rough-stuffing, 80.

rubbing down, 80*

second coat, 80.

to prepare raw oil for, 81.

varnishing and striping, 80.

—— yellow colours, 81.

Carriages, repainting, 82.

Carriage varnish, 64, 65.

Carved cabinet work, polish for, 87.

Carving, polishing wood, 85.

Cart coverings, waterproofing, 368.

Casing books, 396.

Casting, Britannia metal for, 10.

Castings, softening, 26.
Cast iron, cleaning, 176.

— silvering, 319. softening, 26.

soldering to brass, 366.

Casts, paper, 430.
Cast steel, tempering, 26.
Catgut, to make, 21.
Caustic, lunar, 239.

soda, 374,

Cement, acid proof. 22.

. aquariums, 22.

—— architectural. 25. Armenian, 22.

— bottle corks, 22.

builders' waterproof mastic, 123.

Chinese, 24.

cracks in wood, 24.

cutlers', 22.

elastic, 23.

engineers", 25.

—- for iron pots and pans, 25.

Indianite, 23.

iron, 25.

for ivory or mother-of-pearl, 23.

for Jet, 23.

jewellers', 22.

for joining metals, glass, 24.

for joints, 25.

for leather, 24.

—— London. 25.

for marble, 24, 389.

— for meerschaum, 23.

— for mounting photographs, 23. plumbers', 23.

—— turners', 23.

for water-tight wood vessels, 2t.

Cements, 22-25.

how to use, 22.

Chairs, red stain for, 418
Chalks, 348.
Chamois leather, 325.

to dye silk, 32.

Cheap bronze, 17.

india-rubber cement, 23.

Chemical cement, 25.

soldering, 365.

Chinese cement, 24.

lacquer-work, 75.

silver, 13.

white, 94.

Chisels, tempering, 26.
Chloride of gold, 240.

of lime, 15.

opalotype, by collodio, 294.

of silver, 240.

of silver from washing of prints, 292

of zinc, 241.

Chocolate-colour house paint, 108.
Choosing gums and spirits, 73.
Chrome green, 95.

yellow, 95.

Cinnamon brown, to dye silk, 30.
Cinnamon soap, 385.
Claret, to dye cotton, 36.

to dye silk, 31.

to dye woollen, 34.

Clarifying oil for varnish, 62.
-*— tallow, 353.

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