Atom

(at'om.) [Gr. a, not, and tome, a cut.] A part so small as not to be divisible. (Phil.) An ultimate particle of matter. Two opinions, directly opposed to each other, have long had currency with regard to the constituent particles of material things; the one, that matter is composed of an a emblage of minute particles, or atoms, incapable of further division; the other, that there is no limit to its divisibility, the smallest conceivable particle still consisting of an infinity of parts. The first of these theories, which is commonly dist in gui shed by the name of Atomic Philosophy, was originated in Greece by Leu cippus; it was supported by Demo crit us, and subsequently improved by Epicurus and his disciples. The Epicureans profe ed to account for the origin and formation of all things by supposing that these atoms were endued with gravity and motion, and thus came together into the different organized bodies we now see. [s. 58]