this, bathing with water and injecting into the eye a little Cappadocian salts, we apply externally some wool soaked in the white of an egg with rose-oil, and bind it up, and at the same time bind up the sound eye, that it may not move. Then lodging the patient in an apartment below ground, we order him to remain in a state of perfect rest, and upon a spare diet; and the bandages are to be kept on, if nothing prevent, until the seventh day, after which we loose them, and make trial of the sight by presenting him with some object: but this we disapprove of during the operation and immediately after it, lest by the intense exertion the cataract reascend. If the inflammation become urgent we loose the dressing before the seventh day, and must direct our attention to it. * * * * * COMMENTARY. See Celsus (vii, 7); Galen (Ars Medica, 35; Isagoge); Aëtius (vii, 53); Albucasis (Chirurg. ii, 23), Canamusali (vi); Avenzoar (i, 8, 19); Mesue (de Ægr. Oculi; 15); Haly Abbas (Pract. ix, 28); Jesu Hali (Tract. de Oculis, 68); Avicenna (iii, 3, 4, 20); Rhases (ad Mansor. ix, 27, and Cont. ii); Vegetius (Mulom. ii, 17.) This disease is called _suffusio_ by the Latins, and _aqua_ by the Arabians. We have stated in our commentary on affections of the eye, in the Third Book, that the ancients were aware that the crystalline lens is the seat of one of the species of cataract. This opinion is clearly delivered by Galen, Aëtius, Oribasius, Haly Abbas, and some of the others. As a proof that this notion prevailed generally, we will give the words of Psellus literally translated: “Glaucoma is a grievous and incurable affection, being a certain change of the crystalline humour, and transmutation of its colour to a sea-green. The suffusion is a concretion of the fluid between the cornea and crystalline humour.” (Opus Medicum.) The other species then, as Psellus states, was held to be a concretion between the crystalline lens and the cornea. That such a disease, although of comparatively rare occurrence, is sometimes met with seems undeniable.