Part 83

«Pickle for Brass.»—Stir 10 parts (by weight) of shining soot or snuff, 10 parts of cooking salt, and 10 parts of red tartar with 250 parts of nitric acid, and afterwards add 250 parts of sulphuric acid; or else mix 7 parts of aqua fortis (nitric acid) with 10 parts of English sulphuric acid. For the mixing ratio of the acid, the kind and alloy of the metal should be the guidance, and it is best found out by practical trials. The better the alloy and the less the percentage of zinc or lead, the handsomer will be the color. Genuine bronze, for instance, acquires a golden shade. In order to give brass the appearance of handsome gilding it is often coated with gold varnish by applying same thinly with a brush or sponge and immediately heating the metal over a coal fire.

«Pickling Brass to Look Like Gold.»—To pickle brass so as to make it resemble gold allow a mixture of 6 parts of chemically pure nitric acid and 1 part of English sulphuric acid to act for some hours upon the surface of the brass; then wash with a warm solution, 20 parts of tartar in 50 parts of water, and rub off neatly with dry sawdust. Then coat the article with the proper varnish.

«Pickle for Dipping Brass.»—To improve the appearance of brass, tombac, and copper goods, they are usually dipped. For this purpose they are first immersed in diluted oil of vitriol (brown sulphuric acid), proportion, 1 to 10; next in a mixture of 10 parts of red tartar; 10 parts of cooking salt; 250 parts of English sulphuric acid, as well as 250 parts of aqua fortis (only for a moment), rinsing off well in water and drying in sawdust. For obtaining a handsome matt gold color 1⁠/⁠20 part of zinc vitriol (zinc sulphate) is still added to the pickle.

«Restoration of Brass Articles.»—The brass articles are first freed from adhering dirt by the use of hot soda lye; if bronzed they are dipped in a highly dilute solution of sulphuric acid and rinsed in clean water. Next they are yellowed in a mixture of nitric acid, 75 parts; sulphuric acid, 100 parts; shining lampblack, 2 parts; cooking salt, 1 part; then rinsed and polished and, to prevent oxidation, coated with a colorless spirit varnish, a celluloid varnish being best for this purpose.

«Tempering Brass.»—If hammered too brittle brass can be tempered and made {133} of a more even hardness throughout by warming it, as in tempering steel; but the heat must not be nearly so great. Brass, heated to the blue heat of steel, is almost soft again. To soften brass, heat it nearly to a dull red and allow it to cool, or, if time is an object, it may be cooled by plunging into water.

«Drawing Temper from Brass.»—Brass is rendered hard by hammering or rolling, therefore when a brass object requires to be tempered the material must be prepared before the article is shaped. Temper may be drawn from brass by heating it to a cherry red and then simply plunging it into water, the same as though steel were to be tempered.

BRASS, FASTENING PORCELAIN TO: See Adhesives.

BRASS POLISHES: See Polishes.

BRASS SOLDERS: See Solders.

BRASS BRONZING: See Plating.

BRASS CLEANERS: See Cleaning Preparations and Methods.

BRASS PLATINIZING: See Plating.

BRASS, SAND HOLES IN: See Castings.

BRASSING: See Plating.

BREAD, DOG: See Dog Biscuit.

«BREATH PERFUMES:»

See also Dentifrices.

«Remedies for Fetid Breath.»—Fetid breath may be due to the expelled air (i. e., to disease of the respirational tract), to gases thrown off from the digestive tract, or to a diseased mouth. In the first two cases medication must be directed to the causative diseases, with the last, antisepsis principally and the neutralization of the saliva, also the removal of all residual food of dental caries.

I.—Potassium permanganate 1 part Distilled water 10 parts

Mix and dissolve. Add from 5 to 8 drops of this solution to a glass of water and with it gargle the mouth.

II.—Infusion of salvia 250 parts Glycerine 30 parts Tincture of myrrh 12 parts Tincture of lavender 12 parts Labarraque’s solution 30 parts

Mix. Rinse the mouth frequently with this mixture.

III.—Decoction of chamomile 30 parts Glycerine 80 parts Chlorinated water 15 parts

Mix. Use as a gargle and mouth wash.

IV.—Peppermint water 500 parts Cherry-laurel water 60 parts Borax 25 parts

Mix and dissolve. Use as gargle and mouth wash.

V.—Thymol 3 parts Spirit of cochlearia 300 parts Tincture of rhatany 100 parts Oil of peppermint 15 parts Oil of cloves 10 parts

Mix. Gargle and wash mouth well with 10 drops in a glass of water.