Proportion

PROPORTION (Lat. Proportio; Ital. Proporzione). A term used in Arithmetic to express certain harmonious relations existing between the several elements of a series of numbers; and transferred from the terminology of Mathematics to that of Music in which it plays a very prominent part. In Music, however, the word is not always employed in its strict mathematical sense: for, a true Proportion can only exist in the presence of three terms; in which point it differs from the Ratio, which is...