| | Definition: | | \Coal" tar`\
A thick, black, tarry liquid, obtained by the distillation of
bituminous coal in the manufacture of illuminating gas; used
for making printer's ink, black varnish, etc. It is a complex
mixture from which many substances have been obtained,
especially hydrocarbons of the benzene or aromatic series.
Note: Among its important ingredients are benzene, aniline,
phenol, naphtalene, anthracene, etc., which are
respectively typical of many dye stuffs, as the aniline
dyes, the phthale["i]ns, indigo, alizarin, and many
flavoring extracts whose artificial production is a
matter of great commercial importance.
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