CAMPHOR, a white, translucent, crystal line substance occurring in the wood and bark of the camphor laurel (Camphora officinarium, Cinnamomum camphor°, or Laurus camphora), a tree indigenous to Japan and central China, and cultivated in many warm countries. The camphor "gum" is obtained by distilling the leaves, bark and chips of wood with steam, and afterward driving out the water and vola tile oils from the distillate with a low degree of heat, and then subliming the gum at 350 F. Purified camphor consists of a clinging mass of tough, colorless, hexagonal crystals which break apart readily, but cannot be reduced to powder except with the addition of a little al cohol — which evaporates spontaneously during the grinding. It has the chemical formula C,.H,.O, melts at F., boils at 500° F., and sublimes to an appreciable extent at practically all temperatures. It has a strong, pleasant, characteristic odor, and a peculiar, cooling, aromatic taste. Its specific gravity is about 0.992, and it dissolves to a slight extent in water, and freely in alcohol or ether. Small shavings of it exhibit lively motions when thrown upon a water-surface that is abso lutely free from oily matter. (See SURFACE TENSION). It is familiar about the household, on account of its use for protecting furs and woolens from the attacks of moths and other insects, and in domestic medicine. It is also
employed in the manufacture of celluloid and various explosives.
"Synthetic is the name given to a camphor artificially prepared from turpentine oil. It is identical with natural camphor ex cept that it is optically inactive. The process by which it is made consists of first converting the turpentine into pinene hydrochloride (which is known commercially as "artificial camphor"), and then changing this to cam phene by the elimination of the hydrogen chloride. Oxidation of the camphene by any one of several patented processes yields the synthetic camphor.
The name has been given to many similar substances of widely different derivation : as peppermint camphor (menthol) ; cedar camphor (from the oil of juniper) ; cubeb camphor (from the oil of cubebs) ; thymol (from the oil of thyme), etc. At one of the government experiment stations in the South a good yield of natural camphor has been se cured from young seedlings, mown down like grass at the close of the first season's growth, and distilled in the green state. See BORNEOL.