Page:Cowie's Printer's pocket-book and manual.djvu/75

Rh Rh ∺ the mark of geometrical proportion continued, implies the ratio to be still carried on without interruption, as 2, 4, 8, 16, 32, 64 ∺ are in the same uninterrupted proportion.

√ irrationality. The character of a surd root, and shews, according to the index of the power that is set over it, or after it, that the square, cube, or other root, is extracted, or to be extracted; thus, √16, or √²16, or √(2) 16, is the square root of 16, ∛25, the cube root of 25, &c.

—: the differences, or excess.

Q or q, a square.

C or c, a cube.

QQ, the ratio of a square number to a square number.