The application of a cauterizing solution by means of a cotton swab wrapped round the end of a sound may be of service in patients who refuse the actual cautery. To be successful, he insists that the application must be firmly made and must be frequently repeated.
With regard to ophthalmology the older history has always been thoroughly appreciated. Even as early as the time of Hammurabi (2200 b.c.) some rather extensive and interesting surgery of the eye was practised, for the fees for these operations are mentioned in the code. All of the early medieval writers on medicine and surgery—Aetius, Alexander of Tralles, and Paul of AEgina—have paragraphs at least, and sometimes more, with regard to eye operations and the care of the eyes.
Operations above all for cataract have been practised from very early times, and are mentioned also by many medieval writers on medicine and surgery. It is not surprising, then, to find that the medieval surgeons particularly discussed a number of eye diseases and the operations for them. Pope John XXI., who before he became Pope was known as Petrus Hispanus (the Spaniard), and who had been a professor of surgery and a papal physician, wrote a book on eye diseases in the latter half of the thirteenth century, which has come down to us. He had much to say of cataract, dividing it into traumatic and spontaneous, and suggesting operation by needling, a gold needle being used for that purpose. Pope John describes a form of hardness of the eye which would seem to be what we now call glaucoma, and has a number of external applications for eye diseases. Most of his collyria had some bile in them, the bile of various kinds of animals and birds being supposed to be progressively more efficient for the cure of external affections of the eye. This very general use of bile, or of an extract of the livers of animals or fishes, seems to be a heritage from biblical times, when old Toby was cured of his blindness by the gall of the fish.* The Pope ophthalmologist (see Opthal-mology, Milwaukee, January, 1909) recommended the urine of infants as an eye-wash, experience having evidently shown that this fluid, which is usually bland and unirritating, a solution of salts of a specific gravity such that it would not set up osmotic processes in the eye, was empirically of value. In the Middle Ages the idea of using it would be much less deterrent, because it was quite a common practice for physicians to taste urine in order to test it for pathological conditions.
Spectacles were rather commonly used in the Middle Ages, probably having been invented in the second half of the thirteenth century by Salvino de Anna to of Florence. Bernard de Gordon mentions them under the name oculus berellinus early in the fourteenth century. They were originally made from a kind of smoky crystal, berillus, whence the German name Britten and the French besides (Garrison). Guy de Chauliac suggests that when collyria failed to improve the sight spectacles should be employed. Almost needless to say, this use of spectacles meant very much for the comfort and convenience of old people. Up to that time most of those who reached the age of three-score would be utterly unable to read, and would have to depend either on others or on their memory for teaching and many other purposes. External eye troubles, as those due to trichiasis and to various disturbances of the lachrymal apparatus, were treated by direct mechanical means. Some very ingenious suggestions and manipulations were made with regard to them.
* Dr. Petells, discussing this use of livers (Janus, 1898), says that there has been some tendency to revert to the idea of biliary principles as of value in external eye diseases.