or MATRIX. See MATRIX.

MATRIX, or matrix, in Dyeing, is applied to the five simple colours, whence all the rest are derived or composed. These are, the black, white, blue, red, and yellow or root colour.

MATRIX, or matrices, used by the letter-founders, are those little pieces of copper or brads, at one end whereof are engraven, dentifile, or en creux, the several characters used in the composing of books. Each character, virgula, and even each point in a discourse, has its several matrix; and of consequence its several punchen to strike it. They are the engravers on metal that cut or grave the matrices.

When types are to be cast, the matrix is fastened to the end of a mould, so disposed, as that when the metal is poured on it, it may fall into the creux or cavity of the matrice, and take the figure and impression thereof. See Letter FOUNDRY.