matter, 83. Caudate vesicles, 84. Agglomerated granules, 85. Peculiar elements-rods, 86. Bulbs, 87. Modifications in the lower animals, 88. Yellow spot, 89. Modification of the layers at the yellow spot, 91. Researches of Pappenheim, 94. Of Brücke, 95. Of Hannover, 96. Appear- ances of sections of vitreous humors preserved in chromic acid, 97. Appearances of sections of vitreous humors steeped in solution of diacetate of lead, 100. Modification of Brücke's experiments, 102. A different deduction drawn, 104. The frozen vitreous humor, 105. Vitreous humor APPENDIX OF CASES. Cases B.-Sloughing of the cornea in the collapse of scarlet fever . Case C.-Central ulcer of the cornea, healing slowly without the develop. Case D.-Sloughing of the whole cornea from acute inflammation; reten- tion of the lens by its suspensory ligament; subsequent progress of Case E.-Chronic ulcer of the cornea, presenting the appearance of concentric rings; perforation; escape of the aqueous humor; cure Case F.-Intractable ulcer of the cornea, perforating at one point, and afterwards slowly destroying its whole anterior surface Case G.-Chronic vesication of the cornea in an eye the seat of slow Case H.-Acute Glaucoma; subsequent slow disorganization of the cornea; and (in one eye) escape of the humors and retina. Exami- 112 112 Case I.-Symmetrical opacity of both corneæ, consisting of an earthy deposit limited to the anterior elastic lamina, successfully removed Case J.-Symmetrical opacities, similar to the last, successfully removed 120 Case K.-Penetrating wound of the globe, followed by destructive inflam- mation in that eye, and considerable damage to the other,―illus- Case L.-Warty opacity of the cornea, relieved by operation Case M.—Phlebitic ophthalmitis after amputation: with an account of the post-mortem examination of the textures of the eye; and remarks 123 Case N.-Ophthalmitis, similar to that of the last case, but not so clearly of phlebitic origin, accompanying extensive disease of the heart and Case P.-Spontaneous depression of a cataractous lens, from loosening of the suspensory ligament and softening of the vitreous humor . Case Q.-Spontaneous dislocation of the lens into the anterior chamber, probably from previous loosening of the suspensory ligament. Case R.-Loosening of the suspensory ligament of the lens in both eyes; dislocation of one of the lenses into the anterior chamber; singular mobility of the other, by which it falls out of the axis of vision in certain positions of the head, but yet retains its transparency. Cases S.-Minute central specks on the lens and cornea, corresponding Case U.-Dropsy of posterior aqueous chamber, with synechia posterior; bulging of the sclerotica over the ciliary processes. Case V.-Clot of blood in serum occupying the aqueous chambers, under- going very slow absorption during twelve months Tabular Statement of Cases treated at the Royal London Ophthalmic LECTURES, &c. LECTURE I. General view of the eyeball-its size, shape, and tension-Structure of the SCLEROTICA-Implantation of the recti-thickness at different parts. Of the CORNEA-shape-surfaces-thickness-Is it a lens? Of the lamellated tissue-Number of superposed lamellæ-Tubular interstices-Union with sclerotica. Anterior elastic lamina-how tied down-Conjunctival epithelium-Posterior elastic lamina-Marginal plexiform tissue—its triple distribution-Circular sinus-Epithelium of the aqueous humor. GENTLEMEN,-The benevolent founders and supporters of this hospital have ever been desirous that it should not merely minister (as it does so largely) to the relief of the poor of the metropolis and surrounding counties, but that its ample resources should be employed as means of instructing the rising generation of medical men in the very important class of diseases which are daily treated within its walls. I need not inform you particularly of the share it has had in enlarging and diffusing the knowledge of ophthalmic diseases. It will be enough that I refer, as evidence on that point, to the names of Saunders, Farre, Travers, Lawrence, and Tyrrell,—the distinguished men who, for more or less of the first forty years of its existence, were the instruments of its usefulness, and the main source of that amount of celebrity which it has acquired. Of these we can still number but one amongst our present colleagues and I cannot mention the name of Dr. Farre, without a passing acknowledgment B of what this institution owes to him, and of the honour I feel it to be associated with one so venerable and respected.* It is our wish, according to our ability, to continue to make the Ophthalmic Hospital subservient to the same ends as heretofore. The number of patients considerably exceeds that at any former period, being now upwards of 7000 annually, and these afford the means of studying on a great scale the several forms of disease which attack the complex and important organ of sight.† The lectures which we offer are not intended to supersede the necessity of your observing, each one for himself, with minute and accurate attention, the realities of disease and the effects of remedies, but rather, by opening the subject, and acquainting you with the general outlines, to remove the first difficulties from your path, and to stimulate your minds with a fore-taste of the pleasure which all will certainly experience, who devote themselves to the earnest pursuit of knowledge in the field before us. In the arrangements for the present season the task has devolved upon myself of giving you some account of certain structures of the eye-ball, which are of primary consequence to the practitioner, as being those involved in the operations he will be called on to perform, and also as being the seat of several of the more common, as well as severe, morbid actions which affect the organ. That you may form some estimate of the importance of that class especially which belongs to the cornea, I may mention a circumstance which I remarked with concern during a visit to that noble institution the School for the Indigent Blind, in St. George's Fields. It was this-that a very large number of all the cases of total and irremediable blindness which those walls receive are the result of inflammations of the front of the eye, its transparent inlet having been darkened or destroyed by the ravages of disease, which we are quite sure might, in a great majority of instances, have been controlled by skilful and timely *To these distinguished names must be added that of Mr. Dalrymple, who is now retiring from the Institution after a service of nearly twenty years, during which he has contributed to raise its character by his excellent work on the Anatomy of the Eye, published in 1836, and who is about still further to extend its reputation by an admirable series of coloured illustrations of the diseases of treatment. These cases occur amongst the poor-a class to whom the eye is, if possible, even more valuable than to the rich, because without it they can hardly obtain their daily bread, or enjoy the common comforts of existence,—a class, too, among whom it is probable that most of you will be called on to minister during the early years of your professional life. More than this, I think, need not be said to impress you with the importance of the subject which is about engage our attention. to It would be easy to expatiate on the utility of an exact knowledge of the structure of the body to one who desires to study that body in its morbid states; but I am willing to hope that such an argument would be almost superfluous; and at any rate, (that I may not detain you any longer on introductory topics) I shall content myself with observing, that, though a man of genius has now and then become a great physician, like Hippocrates or Sydenham, by an acute and persevering observation of disease, and of the effects of remedies, and without much acquaintance with anatomy, yet that the common voice of mankind proclaims that he who best knows the mechanism of the body will, with a like study of the other departments of medicine, be the best able to comprehend the actions of that body, both in health and disease. General view of the eyeball.-The eyeball, gentlemen, as you know, consists primarily and essentially of a sheet of nervous matter visually endowed,—that is, capable of being so affected by light, that, when duly connected with the sensorium, what we call sight, or perception of light, is the result. This sheet, which we term the retina, is brought towards the surface of the body to meet its appropriate stimulus; and the commissure of nervous substance which connects it to the brain and to the opposite retina is called the optic nerve. In front of the retina are placed transparent media, which, as a whole, refract the light so as to bring it to a focus on the nervous layer, which is spread out in a concave form to receive the more perfect image. The retina is supported behind by a firm resisting tunic, the sclerotica, which is prolonged in front of the transparent media, as a transparent, partly integumental membrane, the cornea. Between the retina and the sclerotica is a very vascular membrane, of a dark brown colour, the choroid, which is advanced behind the cornea under the form of a vertically-hung contractile curtain, the iris, in the centre of which is an aperture, the pupil, capable, by varying its size, of |