Benzene is a hydrocarbon C6H6 formed during the dry distillation of organic substances. It is containedin coal tar, which, on being distilled, yields a light oil that is washed with sulphuric acid and with a solution of soda and again carefully distilled; the portion passing over between 80"' and 90° C. is separately collected and forms benzene. Benzene is a light volatile liquid, very refractive, and has a peculiar gas-like odour. It readily mixes with oils, etc., but not with water, and is a powerful solvent for fats and india-rubber. It is used largely in the manufacture of aniline dyes, for cloth cleaning, and in rubber working. It is very inflammable, burning with a bright, smoky flame.