or Vision. See Anatomy, No 142. and Index subjoined to Optics.

Vol. XIX. Part I.

Imperfection of Sight with regard to Colours. Under the article Colours, is given an instance of a strange deficiency of sight in some people, who could not distinguish between the different colours. In the Phil. Trans. vol. lxviii. p. 611, we have an account of a gentleman who could not distinguish a claret colour from black. These imperfections are totally unaccountable from anything we yet know concerning the nature of this sense.

Second Sight. See Second Sight.