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"),24 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.

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.

POLISHES

There are three principal forms of wood polishes, each of which has its virtues and defects. They are: (a) oil, (b) wax, (c) the varnishes.

(a) Oil. The great advantage of oil polishing is its permanence. It will stand both wetting and warmth and gives a dull, glossy finish. In some woods, as sweet gum and mahogany, it brings up the figure.

Process. Apply either raw or boiled linseed oil diluted with five parts of benzine or turpentine. The advantages of dilution are that the mixture penetrates the wood better, leaves a thinner film on the surface and is more economical. Then rub, rub, rub, day after day. Little and often with unlimited friction, is the best rule. This makes a nice finish for well-fumed chestnut, turning the color to a rich brown.

(b) Wax. Wax is an old English polish, commonly used before French polish and varnish were introduced, especially for hard woods like oak. Its advantages are that it is cheap, easily prepared, easily applied, and easily repaired. Its disadvantages are that it will not stand wetting, is easily marred, requires constant care, is not so hard and dry as varnish, turns slightly sticky with warmth, and is likely to turn white in crevices.

To prepare it. To one part of melted beeswax add one part of turpentine. Mix and cool. It can be bought prepared, as, Bridgeport Wood Finishing Company's "Old Dutch Finish," Butcher's Wax, Johnson's Wax, and others.

Process. Rub the wax evenly over the surface with a stiff brush or the fingers. Let it dry for some hours, and then rub with a cloth: flannel or a piece of felt is best. Put on several coats, leaving the work over night between coats. Rub often with a warm cloth.

(c) Varnishes. The function of varnishes is to cover wood with a hard, transparent coating that is non-porous and impervious to moisture. There is a great range among them, from thin, easily worn, dull finishes to durable, strong, and highly polished coatings called "rubbing varnishes." The polished surface can be secured only by much labor thru the application of successive thin coats of good varnish, carefully rubbed down.

Varnish may be applied to wood, stained, painted, or in its natural condition as well as to metal, leather, paper, and various other substances. A good varnish should be adhesive, that is, it should cling firmly to the surface to which it is applied; it should be elastic, so as not to crack on account of the expansion and contraction of the material to which it is applied; it should dry in a reasonable time; it should be limpid so as to flow easily in application; it should be transparent and brilliant when polished; and it should be durable. The necessary conditions for all good varnishing are a perfectly smooth, even, filled surface of dry wood, a temperature of about 70° and no dust in the air.

In general, there are two classes of varnish, based on the character of the solvent, (1) Spirit varnishes and (2) Oil varnishes.

(1) Spirit varnishes are sometimes made with copal resins dissolved in some spirit, as one of the alcohols, benzine, acetone, etc. They dry with great rapidity owing to the volatilization of the solvent spirit, leaving a coat of pure resin of great hardness and brilliance, but one which is likely to crack and scale when exposed. They are not much used. Shellac is the most common and the most useful of the spirit varnishes. Its basis is resin lac, a compound resinous substance exuded from an East India scale insect (Carteria lacca) found mostly in the province of Assam. The term "lac" is the same as "lakh" which means 100,000 and is indicative of the countless hosts of insects which are the source from which this gum is obtained. The larval insects insert their proboscides into the bark of young shoots of certain lac-bearing trees, varieties of Ficus, draw out the sap for nutriment, and at once exude a resinous secretion which entirely covers their bodies and the twigs, often to the thickness of one-half inch. The females never escape and after impregnation their ovaries become filled with a red fluid which forms a valuable dye known as lac dye. The encrusted twigs are gathered by the natives in the spring and again in the autumn, before the young are hatched, and in this condition the product is known as "stick lac." After being crushed and separated from the twigs and washed free from the coloring matter the product is known as "seed lac." It is then melted and strained and spread out in thin layers in a form called "shell lac." This is what is known as orange shellac in the market. It may be bleached by boiling in caustic potash, and passing chlorine thru it until the resin is precipitated. It is further whitened by being pulled. This is what is known in the market as "white shellac." It comes in lumps. Orange shellac is the stronger and is less likely to deteriorate, but white is easier to apply because it sets less rapidly. Another advantage of the white is its colorlessness. Shellac is soluble in both grain alcohol (ethyl alcohol) and wood alcohol (methyl alcohol), but grain alcohol is preferable. Great care must be taken not to mix even a drop of water in it or it will curdle. To make perfect the process of ordinary filling, shellac may be used as a filler either by itself or preparatory to other processes. Since it dries quickly it can be rubbed down in six or eight hours either with No. 00 sandpaper oiled, or better, with No. 00 steel wool. This process when repeated several times gives a good "egg-shell" finish. It may be applied alone over stained wood or the shellac itself may be colored with aniline dyes cut in alcohol. This, for example, is an easy way to get a black finish.

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Handwork in Wood

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FILLING

POLISHES

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Hebraic Literature; Translations from the Talmud, Midrashim and Kabbala