At a meeting of the Medical Society of the State of Pennsylvania, held at Chambersburg, in May, 1894, I described and demonstrated to Dr. Adolph Koenig, and other members of the Society, the phenomenon of vision which two years later Bowditch briefly described and classified as the retinal circulation. In an address on ophthalmology, delivered before the same Society a few months later, I gave a detailed description of the phenomenon, under the title of "Corneal Corpuscular Activity," which as yet has not been disproved. The theory of its being the perception and recognition of the blood corpuscles in the retinal capillaries is based only on its apparent resemblance to the capillary circulation, for there is no evidence to sustain it. Various observers' opinions in reference to the rate-movement of these bodies differ.
Norton1, in a recent article, says that "their motion is a peculiar, jerky one, each particle