Annealing Steel.—1. For a small quantity. Heat the steel to a cherry red in a charcoal fire, then bury in sawdust, in an iron box, covering the sawdust with ashes. Let stay until cold.—2. For a larger quantity, and when it is required to be very "soft." Pack the steel with cast iron (lathe or planer) chips in an iron box, as follows: Having at least ½ or ¾ inch in depth of chips in the bottom of the box, put in a layer of steel, then more chips to fill spaces between the steel, and also the ½ or ¾ inch space between the sides of box and steel, then more steel; and lastly, at least 1 inch in depth of chips, well rammed down on top of steel. Heat to and keep at a red heat for from two to four hours. Do not disturb the box until cold.
To make Bell Metal.—1. Melt together under powdered charcoal, 100 parts of pure copper, with 20 parts of tin, and unite the two metals by frequently stirring the mass. Product very fine.—2. Copper 3 parts; tin 1 part; as above. Some of the finest church bells in the world have this composition.—3. Copper 2 parts: tin 1 part; as above.—4. Copper 72 parts; tin 26½ parts; iron 1½ parts. The bells of small clocks or pendules are made of this alloy in Paris.
Brass to Make. 1. Fine Brass.—2 parts of copper to 1 part of zinc. This is nearly one equivalent each of copper and zinc, if the equivalent of the former metal be taken at 63-2; or 2 equivalents of copper to 1 equivalent of zine, if it be taken with Liebig and Berzelius, at 31-6.
2. Copper 4 parts, zinc 1 part. An excellent and very useful brass.
Cleansing Solution for Brass.—Put together two ounces sulphuric acid, an ounce and a half nitric acid, one dram saltpetre and two ounces rain water. Let stand for a few hours, and apply by passing the article in and out quickly, and then washing off thoroughly with clean rain water. Old, discolored brass chains treated in this way will look equally as well as when new. The usual method of drying as in sawdust.
To Cover Brass with beautiful Luster Colors.—One ounce of cream of tartar is dissolved in one quart of hot water, to which is added half an ounce of tin salt (protochloride of tin) dissolved in four ounces of cold water. The whole is then heated to boiling, the clear solution decanted from a trifling precipitate, and poured under continual stirring into a solution of three ounces hyposulphite of soda in one-half a pint of water, whereupon it is again heated to boiling, and filtered from the separated sulphur. This solution produces on brass the various luster-colors, depending on the length of time during which the articles are allowed to remain in it. The colors at first will be light to dark, gold yellow, passing through all the tints of red to an irridescent brown. A similar series of colors is produced by sulphide of copper and lead, which, however, are not remarkable for their stability; whether this defect will be obviated by the use of the tin solution, experience and time alone can show.
Bronzing Gun-Barrels.—The so-called butter of zinc used for bronzing gun-barrels is made by dissolving zinc in hydrochloric acid till no more free acid is left; which is secured by placing zinc in the acid until it ceases to be dissolved. The liquid is then evaporated until a drop taken out and placed on a piece of glass solidifies in cooling, when it is mixed with 2 parts of olive oil for every three parts of the liquid. The barrels must be cleansed and warmed before applying the so-called butter, which put on with a piece of linen rag.
Bronzing Fluid.—For brown: Iron filings, or scales, 1 lb.; arsenic, 1 oz.; hydrochloric acid, 1 lb.; metallic zinc, 1 oz. The article to be bronzed is to be dipped in this solution till the desired effect be produced.
Bronze, Green.—Acetic acid, diluted, 4 lbs; green veriter, 2 oz.; muriate of ammonia, 1 oz.; common salt, 2 oz.; alum, ½ oz.; French berries, ½ lb.; boil them together till the berries have yielded their color, and strain. Olive bronze, for brass or copper.—Nitric acid, 1 oz.; hydrochloric acid, 2 oz.; titanium or palladium, as much as will dissolve, and add three pints of distilled water.
To Soften Cast-Iron, for Drilling.—Heat to a cherry red, having it lie level in the fire, then with a pair of cold tongs put on a piece of brimstone, a little less in size than you wish the hole to be when drilled, and it softens entirely through the piece; let it lie in the fire until a little cool, when it is ready to drill.