(From to gape). It is when, from inflammation, the white of the eyes swells above the black circle, so that there appears a gaping aperture. Galen, de Euphoristis, calls it a red and carnous inflammation of the cornea tunica. Paulus calls it che-mosis, when, from a vehement inflammation, both the eye lids are turned outwards, so as scarcely to cover the. eye, and the white of the eye appears higher than the black, and partly hides it. Le Dran calls it a tumour on the white of the eye.

It is really a species of ophthalmia, called by Sau-vages ophthalmia chemosis, and by De Mese-rey, traumatica. The chemosic, or conjinc-tiva cornea palpebraic ophthalmy. Sauvages ascribes it to an external cause, as a violent contusion of the eye, whence an hyposphagna, or to a chirurgical operation performed on the eye, as an extraction of a cataract; to the operation for the unguis, or empyesis, or to an internal cause, as metastasis, or severe catarrh in cacochymic habits. It is known by the black red swelling of the conjunctiva, with a depression and obscurity of the cornea, which seems to lie, as it were, in a cavity. The inflammation is severe, with excruciating pains of the eyes and head, and a sense of weight above the orbit; pervigilium, fever, pulsation, a swelling, and shutting of the eye lids. It terminates sometimes in the suppuration of the eye, and an irremediable blindness or leucomata succeed.

In Dr. Cullen's Nosology, it is a variety of that species of ophthalmy which he names the ophthalmia mem-branarum. When the ophthalmy is in this state, it is for the most part accompanied with violent pain; the white part of the eye resembles raw flesh, or sometimes the pile of red velvet. All the transparent part of the cornea often conies away by suppuration, which destroys the anterior chamber of the eye. The cicatrix, subsequent to the suppuration, hinders the crystalline and vitreous humours from falling out, and by that means the entire destruction of the globe is prevented: sometimes, however, both happen. This disease is often fatal; loss of sight generally follows, and the pain sometimes destroys the patient.

The violence of the disease requires the speediest and 3 K 2 most powerful aids. Repeated bleeding, according to the strength of the patient, with the mostactivepurges, chiefly of the saline kind, will be necessary. A blister may be applied on the forehead, or leeches to the temples; and after them a blister over the part where they were applied. Goulard's saturnine poultice may be applied cold over the eye lids, and renewed as often as it grows warm. Antimonial diaphoretics may be given inwardly, and opium in the largest doses is indispensable. Indeed every method ought to be pursued which can most immediately subdue the inflammatory symptoms. See Nosologia Methodicaoculorum,with Notes by Dr. Wallis, and Ophthalmia.