[121] Japanners' gilding is a branch of oil-gilding, the size or ground being made with 1 pound of linseed oil, to which, while boiling, is added gradually 4 ounces of gum animi in powder, the whole being stirred until the gum is completely dissolved, and kept boiling till the mixture is of a thick consistence, in which state it should be strained through a thick flannel, and stored in a wide-mouthed stoppered bottle. Vermilion is ground up with the size before it is applied, to render it opaque; and if it does not leave the brush freely, it should be thinned with oil of turpentine. The gold powder may be either real gold, or what is called Dutch metal, or imitation gold. Gold powder is produced by grinding the leaf gold with pure honey on the stone till it is perfectly reduced to powder, and afterwards dissolving the mixture in water till the honey is completely removed, and for this several waters are necessary; the water is then poured off, and the powder dried. If this gold be mixed up with weak gum-water and spread upon cockle-shells, it is then called shell gold, which is used in drawings only. The Dutch gold powder is made by reducing the Dutch leaf gold by exactly the same process; and if well protected by varnishing, its appearance is little inferior to the genuine metal. There is another method of procuring gold powder, which is by precipitating grain gold into powder by means of aqua regia, which is made by dissolving four parts of pure spirit of nitre and one part of sal ammoniac in powder. This process was (as has been already stated) well known to the mediæval illuminators. In 4 ounces of this compound, ½ an ounce of grain gold is dissolved under the action of a slight heat; a solution of green vitriol, consisting of copperas 1 dram, water 1 ounce, being gradually added. When the precipitation has ceased, the gold powder must be carefully washed and dried, and will be found to be more brilliant than that made from leaf gold. The use of japanners' gold-size is very similar to oil-gilding, and is equally simple. If the material to be gilded is brought to a smooth and clean face, the size may be laid on at once without other preparation; using great care, however, not to touch any part but what you wish to gild, as the gold will adhere wherever there is size. Priming with a mixture of chalk and size is sometimes used for a first coat, but not by the best japanners, as the work is liable to chip off; no material should therefore be japanned which cannot be made smooth. For hard or close-grained wood, metal, leather, or paper, one or two coats of varnish will answer all requirements; very great care being observed that each coat of varnish be perfectly dry and hard before it is