To Gild Ivory.--Immerse the ivory in a solution of gold in aqua regia, and while damp expose to hydrogen gas, and immediately wash in clear water.
Or prepare a fresh solution of pro tosulphate of iron, dip the ivory in this, and then in a solution of chloride of gold.
To Gild Shells. — Grind gold leaf into a solution of gum arabic in water, and apply to the shells with a brush.
To Gild Silks and Satins.—Trace or paint the desired design with a solution of gold in aqua regia diluted with 3 parts of water, and expose the design while wet to a stream of hy drogen gas. Rinse in clear water. Hydrogen gas is evolved by the de composition of water containing sul phuric acid and iron filings. If the wet cloth is held in these fumes the painted designs will shortly come out in pure gold, and will not tarnish on exposure to the air or in washing.
To Gild Live Fish.—Smear the in side of an earthen bowl with white pitch, warm it gently, and scatter pul verized amber over the pitch. Re move from the fire, add 3 pounds of oleum lini and 1 pound of oleum tere binth mixed together. Cover and boil for 1 hour with gentle heat. Mix with pumice stone to the consistency of paint. Take a live fish from the water, dry it by means of a cloth, and apply this paint with a brush. Immediately spread gold leaf over it, and rub dry with a soft cloth. Re turn the fish to the water. The lon ger this varnish is under water the harder it grows, and it does the fish no harm.
To Gild Leather. — Lettering and other designs are stamped on leather, as in bookbinding, by means of gold leaf and suitable tools or stamps. The leather is dusted with finely pow dered rosin or gum mastic. The tool is first heated in an open fire, the heat of which is tested by means of a piece of waste leather. A little experience is required to gauge the degree of heat required. A suitable piece of gold leaf is cut on a leather pad or cushion, properly applied, and the tool pressed down upon it. The de sign will be indented in the leather, the rosin melted, and the gold leaf caused to adhere.
After the designs have all been stamped, wipe off the superfluous gold leaf with a slightly greasy linen cloth, which will cause the excess of gold to adhere. This cloth may be burned and the ash used for gilding, or it may be sold to refiners or allowed for when purchasing additional gold leaf.
To Gild Paper.—To gild the edges of books or other paper, fasten them in a vise in d. horizontal position and apply a size of 4 ounces of Armenian ,bole and 1 ounce of rock sugar dis solved in water and mixed with the white of egg. This size when nearly dry is smoothed with an agate bur nisher, and then slightly moistened with a sponge wrung out of clear water. The gold leaf is cut to the proper width on a cushion, laid on the moistened surface, and when dry bur nished by rubbing with the agate bur nisher from end to end. Or the burnishing is sometimes done over a piece of silk or India paper. A pad of cotton wool is used to lift the gold leaf from the cushion.
To Design in Gold on paper or parchment, dilute common ink with a little glue size. Form the design with this, and when dry moisten slightly with the breath. This will make the leather slightly sticky and cause gold leaf to adhere.
Or grind white lead or chalk with a strong size, and apply with a brush. Lay on the gold leaf before this dries, and afterwards burnish. Or mix gold powder with size, and letter with a brush. This method is supposed to have been used by the monks in il luminating missals, psalters, and ru brics.
Regilding.—To renew gilt molding tarnished by dirt or moisture, apply a weak solution of salts of tartar in water with a soft cloth, and rinse with cold water.
Or, to regild molding, rub down the molding with a moistened cloth dipped in pumice stone. Apply a coat of shellac varnish and a suitable gold size. Cut gold leaf on a leather cush ion to the proper size and lay on by means of a camel's-hair brush, letting the leaf slightly overlap. Burnish with agate or ivory, let stand a day or two to dry, and cover with shellac or copal varnish.