GOLD, SILVER, &C.--To the inexperienced, the laying on of gold or silver may seem a difficult affair; but it is really comparatively easy, especially when gold and silver shells, sold by artists' colormen, are used. These contain the pure metal ground very fine with gum, and need no preparation. When a drop of water is added, the gold can be removed from the shell, and used with the brush in the ordinary way as a color. One brush should be kept for painting gold or other metallic preparations. As silver is liable to turn black, we would advise the use of aluminium instead, which is not affected by the atmosphere. It can be had in shells in the same manner. In applying gold, or other metal, it should be painted very level and even, especially if it is to be burnished, which make irregularities more prominent. Gold that is to be burnished should be applied before any of the coloring is begun, as the burnisher is apt to mark and injure the effect of the adjoining parts. When the gold is laid on, put a piece of glazed writing paper over it, and, with the burnisher, rub the paper briskly, pressing the particles of gold into a compact film: this gives it a smooth even surface. In this way it is principally used, and is called _mat gold_. For _burnished gold_, the paper is removed, and the agate rubbed briskly upon the gold surface, not dwelling too long upon any one part, until a fine, evenly-bright metallic surface is produced. Rubbing the gold lightly with the finger, after touching the skin or hair, facilitates the action of the burnisher. PREPARING FOR WORK, &C.--The vellum or paper having been strained, the surface will, when dry, be perfectly flat and smooth. If the paper or vellum is to be much worked upon, it will be found advantageous to fasten it to a board by drawing-pins or by glueing the edges, having previously damped the back; when this is dry, the surface will be perfectly level, and not apt to bag in working. Paper so mounted should be larger than the size required, to allow for cutting off the soiled margin when completed. To prevent the margins being soiled, a sheet of paper should now be fastened as a _mask_ over the page, with a flap the size of the work cut in it, by folding back portions of which any part of the surface may be worked upon without exposing the rest.