187. JAPANNING
If it be woodwork you are about to japan, it must be prepared with size, and some coarse material mixed with it to fill up and harden the grain of the wood, (such as may best suit the colour to be laid on,) which must be rubbed smooth with glass paper when dry. In cases of accident, it is seldom necessary to resize the damaged places, unless they are considerable.
188. GRINDING COLOURS IN JAPANNING
Be very careful in japanning, to grind your colours smooth in spirits of turpentine, then add a small quantity of turpentine and spirit varnish, lay it carefully on with a camel hair brush, and varnish it with brown or white varnish, according to the colour.
189. COLOURS REQUIRED IN JAPANNING
Flake white, red lead, vermillion, lake, Prussian blue, patent yellow, orpiment, orchres, verditers, vandyke brown, umber, lamp-black, and siennas raw and burnt. With these you may match almost any colour in general use in japanning. For a black japan, it will be found sufficient to mix a little gold-size with lamp-black; this will bear a good gloss, without requiring to be varnished afterwards.
190. TO PREPARE A FINE TORTOISE-SHELL JAPAN
Take 1 gallon of good linseed oil, and 1/2 lb. of umber; boil them together till the oil becomes very brown and thick, then strain it through a coarse cloth, and set it again to boil; in which state it must be continued till it acquires a consistence resembling that of pitch; it will then be fit for use.
191. DIRECTIONS FOR USING TORTOISE-SHELL JAPAN
Having thus prepared the varnish or japan, clean well the substance which is to be japanned; then lay vermillion, tempered with shell-lac varnish, or with drying oil, very thinly diluted with oil of turpentine, on the places intended to imitate the more transparent parts of the tortoise-shell; when the vermillion is dry, brush the whole over with black varnish, tempered to a due consistence with the oil of turpentine. When set and firm, put the work into a stove, where it may undergo a very strong heat, which must be continued a considerable time; if even three weeks or a month it will be the better. This tortoise-shell ground it not less valuable for its great hardness, and enduring to be made hotter than boiling water without damage, than for the superior beauty and brilliancy of its appearance.