Ogden Nicholas Rood, Popular Science Monthly (1879)
“ The rose-red ghost which is thus developed has a color which is complementary to that which called it into existence, and this will also be the case if we employ little squares of other colors: red will give rise to a greenish-blue image, blue to a yellow, violet to a greenish-yellow, etc., the color of the image being always complementary to that which gave rise to it. ”
