Dry distillation

Distillation Dis`til*la"tion (d[i^]s`t[i^]l*l[=a]"sh[u^]n), n. [F. distillation, L. destillatio.] 1. The act of falling in drops, or the act of pouring out in drops. [1913 Webster]

2. That which falls in drops. [R.] --Johnson [1913 Webster]

3. (Chem.) The separation of the volatile parts of a substance from the more fixed; specifically, the operation of driving off gas or vapor from volatile liquids or solids, by heat in a retort or still, and the condensation of the products as far as possible by a cool receiver, alembic, or condenser; rectification; vaporization; condensation; as, the distillation of illuminating gas and coal, of alcohol from sour mash, or of boric acid in steam. [1913 Webster]

Note: The evaporation of water, its condensation into clouds, and its precipitation as rain, dew, frost, snow, or hail, is an illustration of natural distillation. [1913 Webster]

4. The substance extracted by distilling. --Shak. [1913 Webster]

{Destructive distillation} (Chem.), the distillation, especially of complex solid substances, so that the ultimate constituents are separated or evolved in new compounds, -- usually requiring a high degree of heat; as, the destructive distillation of soft coal or of wood.

{Dry distillation}, the distillation of substances by themselves, or without the addition of water or of other volatile solvent; as, the dry distillation of citric acid.

{Fractional distillation}. (Chem.) See under {Fractional}. [1913 Webster]