China Wood Oil, or tung oil is the best drying oil known. This is universally used in China in paints, lacquers, and water-proofing materials, and is now being used, more or less, among varnish makers, both here and in Europe, because of the excellent qualities it possesses.

It is expressed both cold and hot from the seeds of a tree growing in China and Japan. The seeds contain from 40 to 50 per cent. of oil. Its drying properties are remarkable in that, when spread, it dries throughout from top to bottom at the same time, not forming a skin as linseed oil, and some other of the drying oils. It has valuable water resisting qualities forming durable water-proofing and moisture resisting varnishes. It cannot very well be used in the raw state, as it dries opaque, but when boiled with or without dryer at about 230 degrees Fahrenheit it can be used the same as linseed oil and dries transparent, with a soft, velvety lustre. It is well adapted for oiling floors and in the preparation of floor paints and varnishes, and to impart drying qualities and elasticity to cheap varnishes. The average price at which it is sold is 60 cents to 70 cents per gallon, and merits the painter's careful examination. Its color is pale yellow and the oil has a tallowy or dripping odor. It is used also in soap making and as an illuminant.