The present position of ophthalmic science and art / by D.B. St. John Roosa.

  • Roosa, D. B. St. John (Daniel Bennett St. John), 1838-1908.
Date:
1901
Catalogue details

Licence: In copyright

Credit: The present position of ophthalmic science and art / by D.B. St. John Roosa. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    imperfect method of examination. All that Helm- holtz did—but what a mighty all—was to provide us a means—imperfect it is true, but a means—for doing that] which was hitherto impossible—of examining with tolerable but not complete ease the retina, the choroid, the vitreous, the lens, and the optic papilla. Until this time, while here and there were even exhibitions of Ituninous eyes, no one found out the means of making them so, and the principle of optics upon which this illumination depended. One of our own number, Edward G. Loring, gave us the final contribution to ophthalmoscopy—an instrument by which we could thoroughly and easily determine the refraction of the eye. The tilting mirror, sug- gested by Wadsworth of Boston, made a perfect in- strument, as it remains to this day. If no modifica- tions had ever been made since these two men gave us the perfected instrument, ophthalmology would have lost nothing of importance which may be re- vealed by an ophthalmic mirror. Yet, no sooner was Boring’s opihthalmoscope announced and de- scribed, than modfications and alterations, chiefiy of a trivial character, began, and none but the tilting mirror was important. Helmholtz also invented the instrument for measuring the radius of the cornea^—the ophthal- mometer. Helmholtz first did the thing, and gave us the instrument by which an expert in a labo- ratory, with plenty of time at his disposal, could make a corneal measurement. Valuable results came from the use of this ophthalmometer, or keratom- eter, as perhaps it should be called. One of oui own members, Knapp, with Bonders, was the first to avail himself of the instrument as then presented, as well as Dyer, in this country. But these arduous labors were scarcely ever re peated, and the ophthalmometer of Helmholtz passed