among metaphysicians, denotes the idea we have of lasting distance, all whole parts exist together.

Physics, the enlargement or increase of bulk in bodies, chiefly by means of heat. This is one of the most general effects of that subtle principle, being common to all bodies whatever, whether solid or fluid. In some few cases, indeed, bodies seem to expand as they grow cold, as water in the act of freezing: but this is found to be owing to a new arrangement of the particles, or to crystallization; and is not at all a regular and gradual expansion like that of metals, or any other solid or fluid substance by means of heat. In certain metals also, an expansion takes place when they pass from a fluid to a solid state: but this too is not to be accounted any proper effect of cold, but of the arrangement of the parts of the metal in a peculiar manner; and is therefore to be ascribed to a kind of crystallization.

The expansion of bodies by heat is very various, and in solids does not seem to be guided by any certain rule. In the 48th volume of the Phil. Trans. Mr Smeaton has given a table of the expansions of many different substances. See Chemistry Index.