a mathematical instrument consisting of several lines drawn on wood, bras, silver, &c., and variously divided, according to the purposes it is intended to serve; whence it acquires various denominations, as the plain scale, diagonal scale, plotting scale, &c.

Music, sometimes denominated a gamut, a diagram, a series, an order, a diapason. It consists of the regular gradations of sound, by which a composer or performer, whether in rising or descending, may pass from any given tone to another. These gradations are seven. When this order is repeated, the first note of the second is confertaneous with the lowest note of the first; the second of the former with the second of the latter; and so through the whole octave. The second order, therefore, is justly esteemed only a repetition of the first. For this reason the scale, among the moderns, is sometimes limited to an octave; at other times extended to the compass of any particular voice or instrument. It likewise frequently includes all the practical gradations of musical sound, or the whole number of octaves employed in composition or execution, arranged in their natural order.

Architecture and Geography, a line divided into equal parts, placed at the bottom of a map or draught, to serve as a common measure to all the parts of the building, or all the distances and places of the map.