or MATRIX, in dyeing, is applied to the five simple colours, from which all the rest are derived. These are, the black, white, blue, red, and yellow or root colour.

MATRICES used by the letter-founders, are those little pieces of copper or brass, at one end of which are engraven, dentwise, or en creux, the several characters used in the composing of books. Each character, each virgula, and even each point in a discourse, has its respective matrix, and consequently its puncheon to strike it.