Am'auro'sis, a species of blindness in which no change shows in the appearance of the eye and which is caused by a disease of the nerves of vision. Milton, whose blindness was of this sort, called it the "drop serene." Long-continued direction of the eye on minute objects; long exposure to a bright light, to the fire of a forge, to snow; exposure to irritating gases; overfulness of blood, and disease of the brain are the most frequent causes.