The object of filling is to give a perfectly level and non-absorbent basis for varnish covering or other finish. This can be done with shellac carefully rubbed down with fine oiled sandpaper, but this method requires much toil and patience, and has therefore been given up by furniture finishers. The best fillers, (such as "Wheeler's Wood filler"),14 are made of silex in needle-shaped particles mixed with raw linseed oil, japan and turpentine. When applied to wood it should be thinned with turpentine or benzine, and applied with a brush along the grain. As it dries, the color becomes grayish and it should then be rubbed off across the grain with fine shavings or cotton waste. It is best to have fillers of several colors on hand, such as light, black, mahogany, and "golden oak" to be used according to the stain applied. The filler should be applied after staining the wood and should be allowed to dry thoroly, say forty-eight hours, before it is covered with shellac or varnish. Its use is more necessary on open grained woods, like oak, chestnut, and mahogany, than on close grained woods, like whitewood, maple, and pine, but it is best to use it on all woods that are to be highly polished.
Footnote 14: Made by the Bridgeport Wood Finishing Co., 155 Fulton St., N. Y.
Cans should be kept tightly covered when not in use. Since oil darkens wood, if wood is to be kept light, a filler without oil, as whiting and turpentine, should be used.