The art of lacquering includes various steps, which are divulged as little as possible. Without them nothing but a varnish of good quality would be realized. Thus in Tonkin, where the abundant production is the object of an important trade with the Chinese, it is so used only for varnishing, while in China the same product from the same sources contributes to most artistic applications.

(See also Enamels, Glazes, Paints, Varnishes, and Waterproofing.)

When the Annamites propose to lacquer an object, a box, for example, they first stop up the holes and crevices, covering all the imperfections with a coating of diluted lac, by means of a flat, close, short brush. Then they cover the whole with a thick coating of lac and white clay. This clay, oily to the touch, is found at the bottom of certain lakes in Tonkin; it is dried, pulverized, and sifted with a piece of fine silk before being embodied with the lac. This operation is designed to conceal the inequalities of the wood and produce a uniform surface which, when completely dry, is rendered smooth with pumice stone.

If the object has portions cut or sunk the clayey mixture is not applied, for it would make the details clammy, but in its place a single, uniform layer of pure lac.

In any case, after the pumicing, a third coating, now pure lac, is passed over the piece, which at this time has a mouse-gray color. This layer, known under the name of sou lot, colors the piece a brilliant black. As the lac possesses the remarkable property of not drying in dry air, the object is left in a damp place. When perfectly dried the piece is varnished, and the desired color imparted by a single operation. If the metallic applications are excepted, the lac is colored only black, brown, or red.

The following formulas are in use:

Black

One part of turpentine is warmed for 20 minutes beyond the fusing point; then poured into 3 parts of lac; at the same time pheu deu (copperas) is added. The mixture is stirred for at least a day, sometimes more, by means of a large paddle.

Maroon

This is prepared by a process similar to the preceding, replacing half of the copperas by an equal quantity of China vermilion.

Red

The lac, previously stirred for 6 hours, is mixed with hot oil of trau, and the whole is stirred for a day, after which vermilion is added. The latter should be of good quality, so as to have it brilliant and unchangeable.

The operation of lacquering is then ended, but there are parts to be gilded. These are again covered with a mixture of lac and oil of trau. When this layer is dry the metallic leaves are applied, which are themselves protected by a

coating, composed also of lac and oil of trau. All these lac and oil of trau mixtures are carefully filtered, which the natives effect by pressing the liquid on a double filtering surface formed of wadding and of a tissue on which it rests. It can only be applied after several months when the metallic leaf is of gold. In the case of silver or tin the protecting coat can be laid on in a few days. It favorably modifies the white tints of these two metals by communicating a golden color. The hue, at first reddish, gradually improves and acquires its full brilliancy in a few months.

Little information is procurable concerning the processes employed by the Chinese. The wood to be lacquered should be absolutely dry. It receives successive applications, of which the number is not less than 33 for perfect work. When the lac coating attains the thickness of 1/2 of an inch it is ready for the engravers. The Chinese, like the inhabitants of Tonkin, make use of oil of trau to mix with the lac, or oil of aleurites, and the greatest care is exercised in the drying of the different layers. The operation is conducted in dim-lighted rooms specially fitted up for the purpose; the moisture is maintained to a suitable extent by systematically watering the earth which covers the walls of this " cold stove."