Pyroxylic Spirit (also known as pyrolig-neous spirit or ether, wood spirit or naphtha, methylic alcohol, hydrate of methyle, etc.), a spirituous liquid, not a product of fermentation, but forming one of the most volatile constituents of pyroligneous acid, from which it is obtained in the process of purifying this acid by distillation; formula CH4O. (See Acetic Acid, and Naphtha.) When purified, wood spirit is a colorless liquid of a penetrating em-pyreumatic odor, and a disagreeable burning taste. It is very inflammable, burning like alcohol with a blue flame. It mixes wiih water, alcohol, and ether in all proportions. It boils at 150°, and at 68° its specific gravity is 0.798; at 32°, 0.8179. The substance was first recognized by P. Taylor in 1813; but its properties were first explained by Dumas and Peligot in 1835. In Great Britain wood naphtha, not being subject to the excise duty, has been a valuable substitute for alcohol in various manufactures. By repeated rectifications over lime or chalk, and rejecting the latter portions in the distillations, it was obtained of strength varying from 80 to 90 per cent. of pure spirit, and of specific gravity from 0.87 to 0.83. From its property of dissolving the resins it was much used in the production of varnishes, lacquers, etc, and by the hatters for their solutions of shellac.
The medical properties of wood naphtha have not been fully investigated, but it has been regarded as narcotic, sedative, and anti-emetic. At present it is little used, if at all. Berthelot has prepared wood spirit artificially by acting upon marsh gas with chlorine, and decomposing the chloride thus obtained by means of a solution of potash.