intimate relation which they have to each other, will see the necessity and propriety of their diseases being treated in conjunction. My experience in the cure of diseases of the ear furnishes me with another strong argument, which of itself would have been amply sufficient to induce me to join the treatment of the eye and ear, namely, that while curing deafness I have often learnt from patients that their sight was also improved. This fact, as I have before stated, stimulated me to increased diligence; and I accordingly directed my researches to the structure and functions of these organs, with especial reference to what was mutual between them. Indeed, this is the chief reason which has induced me to add the profession of the Oculist to that of the Aurist; and to all who feel for their suffering fellow-creatures, and to whom the relief of the afflicted affords more satisfaction than quibbling about imaginary encroachments, and the preference of private interest to the public well-being, I feel convinced that I have said sufficient to account for the step I have taken, and for the book now presented to the world. There is no lack of learned and scientific books on the eye; but hitherto I have met with no work that conveys, in a plain and intelligible manner, such information as it concerns every person to know. It is therefore my design, in the following pages, to lay before the public such a work as may be readily understood by the nonprofessional reader, while, at the same time, it shall contain whatever is necessary to the scientific treatment of the principal diseases of the eye. I may here observe, that Professor Robbi, of Leipsic, who has done me the honour to translate my works on the Ear into the German language, and to dedicate his valuable Encyclopædia of Anatomy to me, has communicated some important information on the eye, of which I have taken advantage in the treatment of its diseases. In relation to affections of the eye, I shall here merely add, that I conceive them to be all nearly the same disease, varying only in situation and degree, and that they are derived from similar sources. Still, we are not to consider them all as absolutely alike, and requiring precisely the same treatment; but must endeavour to trace the cause of disease, arrest it in its progress, and restore the healthy functions. The late Mr. Abernethy also thought so, and in his treatment he was generally right. These affections most commonly arise from derangement of the digestive organs, acting on the ganglia and great sympathetic nerve, which has such an extensive influence on the whole system. It is from medical men not bearing this in mind, that cases often seem incurable, and are found so troublesome. No diseases are more acutely painful, or occasion greater privations, than those of the eye. It is therefore remarkable, that, though much has been written, and many elaborate treatises published on the subject, we are still far behind in the practice of ophthalmic surgery. It must be confessed, that the moderns are better acquainted with the treatment of diseases of the eye than the ancients were; yet the zeal of the latter has not hitherto been surpassed. If we examine the works published since Scarpa's Practical Observations on the principal Diseases of the Eyes, which appeared about the end of the eighteenth century, we shall find very little new on the subject beyond what he or his predecessors have com municated.* There is, consequently, ample scope for improvement. * Out of the many descriptions of the eye that have been published, I select the following, as deserving the attention of the practitioner:— Fallopii Instit. Anat. Op. tom. i. pp. 454—6. Kepler Paralipomena, cap. v. pp. 158-168. Cheselden's Anatomy, ch. vi. p. 290 et seq. Winslow's Anatomy, sect. 10. art. 2. vol. ii. p. 284 et seq. Porterfield on the Eye, vol. i. Book 2. Boerhaave, Prælect. § 508 et seq. tom. iv. p. 44 et seq. Camper de quibusdam Oculi part. Haller El. Phys. lib. xvi. sect. 2. Oper. Min. tom. iii. p. 218. et Arter. Oculi Hist. cum tab. in Icon. Anat. Fas. 7. Warner's Description of the Eye. Linn. Descrip. Anat. Oculi Hum.; et in Comment. Gott. tom. iv. p. 192. Sommering's elaborate Icon. Oculi Hum., and the transcript of the same by Caldani, pl. 93-5. D. W. Sommering de Oculis Hominis Animaliumque Commentatio. Blumenbach Instit. Phys. sect. xvii. § 255-268. Monro's (sec.) Three Treatises. Bichât, Anat. Descript. tom. ii. p. 416 et seq. Cuvier, Leç. d'Anat. Comp. No. 12, tom. ii. p. 264 et seq. Bell's Anat. vol. iii. Part 2. Book 1. p. 224 et seq. Monro's (tert.) Elements, Part 6, ch. iii. s. 2. p. 392 et seq. In order to obtain a correct knowledge of the diseases of the eye, it is essentially necessary to have a thorough and intimate acquaintance with the anatomy* and functions of this intricate organ. Of the truth of this, every one must be sufficiently convinced who gives the subject even a moderate degree of attention. Although this is obviously not the place to enter into a detailed account of the anatomy of the entire skeleton, and as I have embraced in the chapter on the physiology of the eye what *The Greeks are the first people of whom we have any authentic account who studied anatomy as a science. It is probable that they first derived their knowledge from the eastern nations, particularly the Ethiopians and Egyptians, from the circumstance of anatomy in its infancy being so closely connected with astronomy, which those nations had peculiar opportunities of cultivating. Thales, surnamed the Wise, was the first anatomist we hear of, and he lived 500 years before Christ. No progress, however, was made in this science till the time of Hippocrates, who was contemporary with Socrates, Xenophon, and Plato, about 400 years before the Christian era. The first dissection we have upon record was made by Democrates of Abdera, who had for his subject a hog. From the time of Hippocrates, however, the science was gradually improved till the time of Galen, who lived in the second century, that is, 600 years after Hippocrates. Galen cultivated |