COMPOSITION, in Chemistry, is the union and combination of several substances of different natures, from which a compound body results. From this union of bodies of different natures, a body is formed, of a mixed nature, which Becker and Stahl have called a mixture, and which may be called a combination, or chemical composition, to avoid the equivocal sense of the word mixture. By this last, we understand only a mere apposition of parts; and which would therefore give a very false idea of chemical composition, in which a mutual adhesion takes place between the combined substances.