Goethe's Theory of Colours · Johann Wolfgang von Goethe
296.
Here, it is true, the refraction is done away with by the opposition of the two; but as the prism _h_, in displacing the square by refraction through three compartments, produces coloured borders wider by a third than those produced by the prism _g_, so, notwithstanding the refraction is neutralised, there must be an excess of coloured border remaining. (The position of this colour, as usual, depends on the direction of the apparent motion (204) communicated to the square by the prism _h_, and, consequently, it is the reverse of the appearance in the two squares 2 and 3, which have been moved in an opposite direction.) This excess of colour we have called Hyperchromatism, and from this the achromatic state may be immediately arrived at.
Text from Project Gutenberg, public domain in the United States.