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remove the sal-ammoniac from the surface, placed immediately on the former and lined at the same heating.

Blanched Copper.-Fuse 8 oz. of copper and oz. of neutral arsenical salt, with a flux made of calcined borax, charcoal dust, and powdered glass.

Yellow Brass.-30 parts of zinc and 70 of copper in small pieces.

YELLOW BRASS, for Turning.(Common article.)-Copper, 20 lbs.; zinc, 10 lbs.; lead from 1 to 5 oz. Put in the lead last before pouring off.

Red Brass, for Turning.-Copper, 24 lbs.; zinc, 5 lbs.; lead, 8 oz. Put in the lead last before pouring off.

RED BRASS, free, for Turning.Copper, 160 lbs.; zinc, 50 lbs.; lead, 10 lbs.; antimony, 44 oz.

Another Brass, for Turning. Copper, 32 lbs. ; zinc, 10 lbs. ; lead, 1 lb.

Best Red Brass, for fine Castings.-Copper, 24 lbs.; zinc, 5 lbs. ; bismuth, 1 oz. Put in the bismuth last before pouring off.

Rolled Brass.-32 copper, 10 zinc, 1.5 tin.

Common Brass, for Castings.-20 copper, 1.25 zinc, 2.5 tin.

Hard Brass, for Casting.-25 parts copper, zinc, 4.5 tin.

Brass Melting.-The best plan of smelting brass is to melt the copper in a black-lead crucible first, dry and cool the zinc as much as possible and immerse the whole of the zinc into the copper when the latter is not hotter than barely to continue fluid. Drop a piece of borax the size of a walnut into the pot. When the surface of the hot metal is covered by fine charcoal, or borax, which is prevented by renewal from burning, the smallest loss of zinc is sustained.

The melting together of tin and copper is less difficult than that of zinc and copper, because tin is not so liable to evaporate as zinc, and little metal is lost. The appearance of the alloy may be improved by covering the melted metal with about one per cent. of dried potash; or, better still, a mixture of potash and soda. This flux has a re

markable influence on the colour, and particularly on the tenacity of the alloy. The former becomes more red, and the latter stronger. The scum forming on the surface by this addition ought to be removed before the metal is cast. Tin and copper are liable to separation in cooling; this can be prevented, at least partly, by turning the mould containing the fluid metal, and keeping it in motion until it is chilled.

Copper and lead unite only to a certain extent: 3 lead and 8 copper is

ordinary pot metal. All the lead may be retained in this alloy, provided the object to be cast is not too thick. When the cast is heavy, or much lead is used, it is pressed out by the copper in cooling. 1 lead, 2 copper, separates lead in cooling-it oozes out from the porcs of the metal: 8 copper and 1 lead is ductile, more lead renders copper brittle. Between 8 to 1 and 2 to 1 is the limit of copper and lead alloys. All of these alloys are brittle when hot or merely warm.

Equal parts of copper and silver and 2 per cent. of arsenic form an alloy similar to silver, a little harder, however, but of almost equal tenacity and malleability. Antimony imparts a peculiar beautiful red colour to copper, varying from rose-red in a little copper and much antimony, to crimson or violet when equal parts of both metals are melted together.

Hardening for Britannia.— (To be mixed separately from the other ingredients.)-Copper, 2 lbs. ; tin, 1 lb.

Good Britannia Metal.-Tin, 150 lbs.; copper, 3 lbs.; antimony, 10 lbs.

Britannia Metal, 2nd quality.— Tin, 140 lbs.; copper, 3 lbs. ; antimony, 9 lbs.

BRITANNIA METAL, for Casting.Tin, 210 lbs.; copper, 4 lbs. ; antimony, 12 lbs.

BRITANNIA METAL, for Spinning.Tin, 100 lbs.; Britannia hardening, 4 lbs.; antimony, 4 lbs.

BRITANNIA METAL, for Registers.— Tin, 100 lbs.; hardening, 8 lbs.; antimony, 8 lbs.

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BEST BRITANNIA, for Spouts.-Tin, 140 lbs.; copper, 3 lbs.; antimony, 6 lbs.

BEST BRITANNIA, for Spoons.-Tin, 100 lbs. ; hardening, 5 lbs.; antimony, 10 lbs.

BEST BRITANNIA, for Handles.Tin, 140 lbs.; copper, 2 lbs. ; antimony, 5 lbs.

BEST BRITANNIA, for Lamps, Pillars, and Spouts.-Tin, 300 lbs.; copper, 4 lbs.; antimony, 15 lbs.

BRITANNIA, for Casting. - Tin, 100 lbs.; hardening, 5 lbs. ; antimony, 5 lbs.

Lining Metal, for Boxes of Railroad Cars.-Mix tin, 24 lbs. ; copper, 4 lbs.; antimony, 8 lbs. (for a hardening); then add tin, 72 lbs.

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Bronze Metal. (1.) Copper, 7 lbs.; zinc, 3 lbs.; tin, 2 lbs. (2.) Copper, 1 lb.; zinc, 12 lbs. ; tin, 8 Ìbs. Artificial Gold.. Pure copper, 100 parts; zinc, or preferably tin, 17 parts; magnesia, 6 parts; sal-ammoniac, 3.6 parts; quicklime, 1.8 part; tartar of commerce, 9 parts. The copper is first melted, then the magnesia, salammoniac, lime, and tartar, are then added, separately and by degrees, in the form of powder; the whole is now briskly stirred for about half an hour, so as to mix thoroughly; and then the zinc is added in small grains by throwing it on the surface and stirring till it is entirely fused; the crucible is then covered, and the fusion maintained for about 35 minutes. The surface is then skimmed and the alloy is ready for casting. It has a fine grain, is malleable, and takes a splendid polish. Does not corrode readily, and for many purposes is an excellent substitute for gold. When tarnished, its brilliancy can be restored by a little acidulated water.

German Silver, First Quality for Casting. Copper, 50 lbs. ; zinc, 25 lbs. ; nickel, 25 lbs.

GERMAN SILVER, Second Quality for Casting.-Copper, 50 lbs. ; zinc, 20 lbs. ; nickel (best pulverized), 10 lbs.

GERMAN SILVER, for Rolling.-Copper, 60 lbs. ; zinc, 20 lbs. ; nickel, 25 lbs. Used for spoons, forks, and table ware.

GERMAN SILVER, for Bells and other Castings.--Copper, 60 lbs.; zinc, 20 lbs.; nickel, 20 lbs; lead, 3 lbs.; iron (that of tin plate being best), 2 lbs.

In melting the alloy for German silver it is difficult to combine a definite proportion of zinc with the compound of nickel and copper previously prepared. In fusing the three metals together there is always a loss of zinc by volatilization, which may be lessened by placing it beneath the copper in the crucible. The best method is to mix the copper and nickel, both in grains first, place them, thus mixed, in the crucible, when melted add the zinc and a piece of borax the size of a walnut. The zinc will gradually dissolve in the fluid copper, and the heat may be raised as their fluidity increases. In this instance, as in all others of forming alloys, it is profitable to mix the oxides of the various metals together, and reduce them under the protection of a suitable flux. The metal nickel can be produced only from pure oxide of nickel; and, as purity of the alloy is essential to good quality, the common commercial zinc is not sufficiently pure for forming argentan. Copper cannot well be used in the form of oxide, but grain copper or wire-scraps will serve equally as well. of Silver. - Tin,

Imitation 3 oz.; copper, 4 lbs. Pinchbeck.-Copper, 5 lbs. ; zinc,

1 lb.

Tombac.-Copper, 16 lbs. ; tin, 1 lb.; zinc, 1 lb.

Red Tombac.-Copper, 10 lbs. ; zinc, 1 lb.

Stereotype Metal.-1 tin; 1 antimony; 4 lead. In using stereotype metal, brush the type with plumbago or a small quantity of oil, then place in a frame, and take a cast with plaster of Paris. The cast is dried in a very hot oven, placed face downwards upon a flat plate of iron; this plate is laid in a tray or pan of iron, having a lid securely fastened, and furnished with a hole at each corner. Dip the tray in the fluid metal, which will flow in at the four corners. When the tray is 1e

remove the sal-ammoniac from the surface, placed immediately on the former and lined at the same heating.

Blanched Copper.-Fuse 8 oz. of copper and oz. of neutral arseniIcal salt, with a flux made of calcined borax, charcoal dust, and powdered glass.

Yellow Brass.-30 parts of zinc and 70 of copper in small pieces.

YELLOW BRASS, for Turning.— (Common article.)-Copper, 20 lbs.; zinc, 10 lbs.; lead from 1 to 5 oz. Put in the lead last before pouring off.

Red Brass, for Turning.-Copper, 24 lbs.; zinc, 5 lbs.; lead, 8 oz. Put in the lead last before pouring off.

RED BRASS, free, for Turning.Copper, 160 lbs.; zinc, 50 lbs.; lead, 10 lbs.; antimony, 44 oz.

Another Brass, for Turning.Copper, 32 lbs.; zinc, 10 lbs. ; lead, 1 lb. Best Red Brass, for fine Castings.-Copper, 24 lbs.; zinc, 5 lbs.; bismuth, 1 oz. Put in the bismuth

last before pouring off. Rolled Brass.-32 copper, 10 zinc, 1.5 tin.

Common Brass, for Castings.-20 copper, 1.25 zinc, 2.5 tin.

Hard Brass, for Casting.-25 parts copper, 2 zinc, 4.5 tin.

Brass Melting.-The best plan of smelting brass is to melt the copper in a black-lead crucible first, dry and cool the zinc as much as possible and immerse the whole of the zinc into the copper when the latter is not hotter than barely to continue fluid. Drop a piece of borax the size of a walnut into the pot. When the surface of the hot metal is covered by fine charcoal, or borax, which is prevented by renewal from burning, the smallest loss of zinc is sustained.

The melting together of tin and copper is less difficult than that of zinc and copper, because tin is not so liable to evaporate as zinc, and little metal is lost. The appearance of the alloy may be improved by covering the melted metal with about one per cent. of dried potash; or, better still, a mixture of potash and soda. This flux has a re

markable influence on the colour, and particularly on the tenacity of the alloy. The former becomes more red, and the latter stronger. The scum forming on the surface by this addition ought to be removed before the metal is cast. Tin and copper are liable to separation in cooling; this can be prevented, at least partly, by turning the mould containing the fluid metal, and keeping it in motion until it is chilled.

Copper and lead unite only to a certain extent: 3 lead and 8 copper is ordinary pot metal. All the lead may be retained in this alloy, provided the object to be cast is not too thick. When the cast is heavy, or much lead is used, it is pressed out by the copper in cooling. 1 lead, 2 copper, separates lead in cooling-it oozes out from the pores of the metal: 8 copper and 1 lead is ductile, more lead renders copper brittle. Between 8 to 1 and 2 to 1 is the limit of copper and lead alloys. All of these alloys are brittle when hot or merely warm.

Equal parts of copper and silver and 2 per cent. of arsenic form an alloy similar to silver, a little harder, however, but of almost equal tenacity and malleability. Antimony imparts a peculiar beautiful red colour to copper, varying from rose-red in a little copper and much antimony, to crimson or violet when equal parts of both metals are melted together.

Hardening for Britannia.(To be mixed separately from the other ingredients.)-Copper, 2 lbs. ; tin, 1 lb.

Good Britannia Metal.-Tin, 150 lbs.; copper, 3 lbs.; antimony, 10 lbs.

Britannia Metal, 2nd quality.— Tin, 140 lbs.; copper, 3 lbs. ; antimony, 9 lbs.

BRITANNIA METAL, for Casting.Tin, 210 lbs.; copper, 4 lbs.; antimony, 12 lbs.

BRITANNIA METAL, for Spinning.Tin, 100 lbs.; Britannia hardening, 4 lbs.; antimony, 4 lbs.

BRITANNIA METAL, for Registers.— Tin, 100 lbs.; hardening, 8 lbs.; antimony, 8 lbs.

BEST BRITANNIA, for Spouts.-Tin, | 140 lbs.; copper, 3 lbs.; antimony, 6 lbs.

BEST BRITANNIA, for Spoons.-Tin, 100 lbs. ; hardening, 5 lbs.; antimony, 10 lbs.

BEST BRITANNIA, for Handles.Tin, 140 lbs.; copper, 2 lbs.; antimony, 5 lbs.

BEST BRITANNIA, for Lamps, Pillars, and Spouts.-Tin, 300 lbs.; copper, 4 lbs.; antimony, 15 lbs.

BRITANNIA, for Casting. - Tin, 100 lbs.; hardening, 5 lbs.; antimony, 5 lbs.

Lining Metal, for Boxes of Railroad Cars.-Mix tin, 24 lbs. ; copper, 4 lbs. ; antimony, 8 lbs. (for a hardening); then add tin, 72 lbs.

Bronze Metal. (1.) Copper, 7 lbs.; zinc, 3 lbs.; tin, 2 lbs. (2.) Copper, 1 lb.; zinc, 12 lbs.; tin, 8 lbs.

Artificial Gold. - Pure copper, 100 parts; zinc, or preferably tin, 17 parts; magnesia, 6 parts; sal-ammoniac, 3-6 parts; quicklime, 1-8 part; tartar of commerce, 9 parts. The copper is first melted, then the magnesia, salammoniac, lime, and tartar, are then added, separately and by degrees, in the form of powder; the whole is now briskly stirred for about half an hour, so as to mix thoroughly; and then the zinc is added in small grains by throwing it on the surface and stirring till it is entirely fused; the crucible is then covered, and the fusion maintained for about 35 minutes. The surface is then skimmed and the alloy is ready for casting. It has a fine grain, is malleable, and takes a splendid polish. Does not corrode readily, and for many purposes is an excellent substitute for gold. When tarnished, its brilliancy can be restored by a little acidulated water.

German Silver, First Quality for Casting.-Copper, 50 ĺbs.; zinc, 25 lbs.; nickel, 25 lbs.

GERMAN SILVER, Second Quality for | Casting.-Copper, 50 lbs. ; zinc, 20 lbs.; nickel (best pulverized), 10 lbs.

GERMAN SILVER, for Rolling.-Copper, 60 lbs.; zinc, 20 lbs. ; nickel, 25 lbs. Used for spoons, forks, and table ware.

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GERMAN SILVER for Bells other Casting Copper.

20 lbs; nickel, 20 lbs: land.. iren (that of tin plate being best), I is.

In melting the alloy for GermAZ SLver it is difficult to combine a definite proportion of zinc with the empezad of nickel and copper previously pre pared. In fusing the three mets together there is always a lows of by volatilization, which may be lessened by placing it beneath the cuppur in the crucible. The best method is to m the copper and nickel, both in grains first, place them, thus mixed, in the crucible, when melted add the zine ani a piece of borax the size of a wilant. The zine will gradually dissolve a the fluid oopper, and the heat may be rivei as their fluidity increases. In this instance, as in all others of forming alloys, it is profitable to mix the crudes of the various metals together, and reduce them under the protection of a suitable flux. The metal nickel can be produced only from pure cride of nickel; and, as purity of the ay is essential to good quality, the ermmia commercial zine is not sufficiently pure for forming argentan. Copper cannet well be used in the form of cride, but grain copper or wire-scrips will serve equally as well. Imitation of Silver.-T., 3 oz.; copper. 4 lbs. Pinchbeck.-Copper, 5 lbs. ; zine,

1 lb.

Tombac.-Copper, 16 lbs. ; tin, 1 lb.; zinc, 1 lb.

Red Tombac.-Copper, 10 lbs. ; zine, 1 lb.

Stereotype Metal.-1 tin: 1 antimony; 4 lend. In using stereceme metal, brush the type with plume go or a small quantity of ell, then place in a frame, and take a cast with plaster of Paris. The cast is dried in a very hot oven, placed face downwards upon a flat plate of iron; this plate is in a tray or pan of iron, having a securely fastened, and furnished

hole at each corner. Dip the try the fluid metal, which will 4ow in at the four corners. When the tray is e

moved, dip the bottom only in water; and as the metal contracts in cooling, pour in melted metal at the corners so as to keep up the fluid pressure, and obtain a good solid cast. When cool open the tray; remove the cake of plaster and metal, and beat the edges with a mallet to remove superfluous metal. Plane the edges square, turn the back flat, in a lathe, to the required thickness, and remove any defects. If any letters are damaged cut them out, and solder in separate types instead. Finally, fix upon hard wood to the required height.

Casting Stereo-Plates by the Paper Process.-Lay a sheet of tissue paper upon a perfectly flat surface, and paste a soft piece of printing paper, which must be pressed evenly on, to the tissue. Lay the paper on the form, previously oiled, and cover with a damp rag; beat with a stiff brush the paper in evenly, then paste a piece of blotting paper, and repeat the beating in; after which about three more pieces of soft tenacious paper must be pasted and used in a similar way; back up with a piece of cartridge paper. The whole must then be dried with moderate heat, under a slight pressure. When thoroughly dry, brush well over with plumbago or French chalk. When this is done it is ready for the matrix. This is a box of a certain size for the work required, the interior of which is type high. In it is what is termed a gauge, which lifts out to insert your paper cast, and is regulated by hand to the size of the plate required. This being placed inside, the lid is shut down and screwed tight, with the end or mouthpicce left open. By this orifice the metal is poured in, and, as it is mounted to swing, the box is moved about so as to well throw down the metal and make a solid cast. Then water is dashed on the box, the screw-bar unshackled, the lid lifted, the plate taken off, and the paper cast is again ready for work.

Fusible Metal.-1. Bismuth, 8 parts; lead, 5 parts; tin, 3 parts: melt together. Melts below 212° Fahr. 2. Bismuth, 2 parts; lead, 5 parts;

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or

Alloy for Tam-Tams, Gongs.-80 parts of copper and 20 of tin, hammered out with frequent annealing. An alloy of 78 of copper and 22 of tin answers better, and can be rolled out.

Alloy for Bells of Clocks.The bells of the pendules, or ornamental clocks, made in Paris, are composed of copper 72.00, tin 26.56, iron 1.44 in 100 parts.

Bell Metal, fine.-71 copper, 26 tin, 2 zinc, 1 iron.

BELL METAL, for large Bells.-Copper, 100 lbs.; tin, from 20 to 25 lbs. BELL METAL, for small Bells.-Copper, 3 lbs.; tin, 1 lb.

Cock Metal.-Copper, 20 lbs. ; lead, 8 lbs.; litharge, 1 oz.; antimony, 3 oz.

Alloy for Journal Boxes.Copper, 24 lbs.; tin, 24 lbs.; and antimony, 8 lbs. Melt the copper first, then add the tin, and lastly the antimony. It should be first run into ingots, then melted and cast in the form required for the boxes.

Queen's Metal.-A very fine silver-looking metal is composed of 100 lbs. of tin, of regulus of antimony, 1 of bismuth, and 4 of copper.

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