RED

, in Physics, or Optics, one of the simple or primary colours of natural bodies, or rather of the rays of light.—The Red rays are the least refrangible of all the rays of light. And hence, as Newton supposes the different degrees of refrangibility to arise from the different magnitudes of the luminous particles of which the rays consist; therefore the Red rays, or Red light, is concluded to be that which consists of the largest particles. See Colour and Light.

Authors distinguish three general kinds of Red: one bordering on the blue, as colombine, or dove-colour, purple, and crimson; another bordering on yellow, as flame-colour and orange; and between these extremes is a medium, which is that which is properly called Red.