Unbleached calico is generally used for cheap oilskins, fine drill for better-class goods, and sometimes, but rarely, silk. Best linseed oil, with very little driers, is the most suitable dressing, and should take about two months to dry in a cool, airy place. Lampblack is the cheapest suitable black; ivory black is better, but dearer.
One pound to 2 lb. of lampblack may be used for 1 gal. of oil. If oil alone is used, 1 lb. to 1 1/2 lb. of driers for 1 gal. of oil may be added; with lampblack, 2 lb. to 3 lb. of driers. Ochre is the only yellow pigment cheap enough to use. If the solution has to be made quickly, use plenty of driers, and hang the articles up to dry in a room artificially heated. The solution should be laid on with a stiff brush or scraper in a thin layer, and the first coat must be allowed to become thoroughly dry before putting on a second; two or three coats will be required. The articles should be hung on sticks so that no two portions of the cloth touch. Boiled oil, coloured with ochre or lampblack, and a dash of driers is also used. It is recommended, in order to keep the oilskins from becoming stiff, that yellow soap cut into shreds should be dissolved in the waterproofing paint, the proportions being 1 oz. of soap to 3pt. of paint. A little beeswax dissolved in the paint is also used for the same purpose. A good black dressing is boiled oil and lampblack 1 qt., to which the white of five eggs and l oz. of melted beeswax are added; give two coats, and allow each coat to dry thoroughly before the next is applied. The drying will occupy quite two weeks.
If the drying is not thorough the dressing will become sticky. If driers is used the oilskins are apt to crack. If the dressing is too thickly applied it will peel off where exposed to friction.