Smoke

(smok.) [From A. S. smoca.] (Chem.) The visible vapor or exhalation that is expelled from a substance while burning; or the rarefied, but un decomposed part of a combustible. The S. emitted by fuel may be considered as so much waste of its most valuable portions. A scientific application of the principles on which combustion depends is quite sufficient to prevent the production of S. The word S. is particularly applied to the volatile vapor expelled from coal, wood, vegetable matter, .; that which exhales from metallic substances being more generally called fume. [s. 833]