SCALE (1) A  small thin flake, plate or shell . The word. in O . Eng. is sceale, so bean-sceale, the husk or pod of a bean; cognate forms are found in Ger . Schale, O.H.G . Scale, from which the O . Fr. escale, modern gcale, is borrowed . The ultimate root is seen in the closely allied " shell," and also in skull, scalp, shale and skill, and means to peel off, separate, divide . The word is used specifically (1) in botany, of the rudimentary flake-like leaf forming the covering of the leaf-buds of deciduous trees and of the bracts of the cone in conifers; (2) in zoology, of the flat, hard structures of the epidermis or exoskeleton in fishes, reptiles . Thus in ichthyology the various types of scales are classed as cycloid (Gr. abaor, circle), where the growth is in layers, equally from the anterior and posterior edges; ctenoid (Gr . KTIv, comb), where the posterior edge is toothed; ganoid (Gr. yavor, shining), with a hard enamelled surface and usually rhomboidal in shape, and placoid (Gr. irXii , tablet), as in the ossified papillae of the cutis of the shark . In reptiles the term is applied to the structures which form the covering of the true reptiles, snakes and lizards . In entomology the downy covering au-apended cradle baaf of the wings of lepidoptera consists of minute scales, really modifications of hairs, covered with fine lines, giving the bright colours .

Another form in O . Eng. scale is found glossing the

Lat. lanx, flat bowl or dish, and is thus used of the dishes or cups of a balance (bilanx), the instrument itself being also called " scales." 2 . Properly a ladder, flight of steps, now only used in the derived " scaling ladder." The word is derived from the Lat. scala (originally scandla, from scandere to climb) . There are many transferred senses of the word, e.g. the distinguishing marks for purposes of measurement on a rule or other measuring instrument; hence a graduated measure or a system of proportional measurement or numeration, and particularly, in music, a series of tones at definite standard intervals (see HARMONY, MUSICAL NOTATION) .