Where white paper varnish is necessary, that which is termed crystal paper or fine pale paper varnish is used. The first is the whitest; and as it can contain but little linseed oil, it requires very expeditious and experienced working when used over large surfaces. Crystal paper, copal cabinet, and quick furniture varnishes come under the heading of volatile oil varnishes; so does mastic varnish, used for varnishing papers, maps, etc.
White hard and brown hard spirit varnish are the two most useful among the purely spirit varnishes. They are similar in nature to French polish, all being prepared from various kinds of lac—shellac, etc.—and spirits of wine, or methylated spirit. The luster they give is nearer to that of French polish, and "softer" than that given by a copal oil: hence white hard and brown hard are much used for furniture as a substitute for the more tedious process of French polishing, and also upon those portions where the polisher's rubber could not be used.
Bath Varnish is a very hard-drying white liquid, similar in nature to the enamels now on the market, but is a more durable article, and re sists the action of hot water to a greater extent than the other preparations.
There are a few vehicles and liquids used by painters which scarcely come under the heading of oils and varnishes. The word varnish is so associated with a glossy surface, that the name flatting or lusterless varnish, given to a prep aration of oil of turpentine, copal, and wax, is somewhat a misnomer. This is not often called for, since it possesses very little body; but upon timbered and ornamental wooden ceilings it can be used with decided advantage over ordinary copal, the small amount of wax gloss it gives out being far more restful and natural for such positions than a bright hard glitter.
Black Japan is a species of black copal var nish, made in various qualities, the best being that for carriage painting. House-painters sel dom use it for other than blacking grates or iron-work, although there are many other pur poses for which it can be used. Thinned down with turps, it makes a capital stain of a rich brown color for wood.
Berlin Black is another preparation useful for various purposes, as it is a dense black, dry ing with only an eggshell gloss; like Brunswick black, it is prepared chiefly for iron-work.
Varnish Stains are liquids of similar nature and preparation to brown hard spirit varnish, but are colored with permanent vegetable dyes, to represent, when spread on clean white wood, the various colors of oak, walnut, mahogany, etc. When applied without any previous prep aration, two coats are necessary to get a glossy effect upon new wood. As a varnish and stain combined, they are most useful and convenient for picture-frames, fretwork, and other little matters.
Patent Knotting, or Knotting Composition, is a brown spirituous varnish, used chiefly for touching over the knots in woodwork previous to the priming, or first coating, with paint. It is also useful for coating over stains and other effects of dampness on walls previous to paint ing them.
Japan or Japanners' Gold Size is a liquid used for a variety of purposes. Japan gold size is a preparation of linseed oil and litharge, and will usually dry in about half an hour. Although the name appears to connect it with processes of gilding, it is seldom used for that purpose, but rather as a liquid drier in combination with turps and flatting paint. When nearly dry, it has to a slight degree that property of tacki ness which is so characteristic of oil gold size, but with very little of the brilliancy of the lat ter. Only on outdoor work, where it is advis able to complete the gilding forthwith, for tem porary work, or for sign writing, can it be recommended as a gold size.
Compositions prepared with japan gold size for hardening them are much used in coach painting, engine work, and, to a minor extent, in house painting and "filling up;" and in pre paring "dead" black from ivory black ground in turpentine, this is also the best and safest binding liquid.
A few words must now be said about driers, as they are very important. Many people use them too freely, to the detriment of the paints. Of these substances there is a considerable variety, which may be used to more or less advantage, according to their chemical nature and their effect upon the color of paint.