The ophthalmoscope : a manual for students / by Gustavus Hartridge.

  • Gustavus Hartridge
Date:
1907
Catalogue details

Licence: In copyright

Credit: The ophthalmoscope : a manual for students / by Gustavus Hartridge. Source: Wellcome Collection.

    49/212 (page 31)
    A useful concave mirror to carry in the waistcoat pocket is shown in Fig. 30. Another convenient form is the double mirror; one concave, of 25 cm. focus, and the other plane; one slides over the other, so that they mutually protect each other and require no case. The student also requires a large biconvex lens (+. 13 D.), which is necessary for focal illumination and the indirect method of examination. A magnifying glass made by cementing together one crown glass lens with tAvo flint glass lenses, and having a focus of l-o cm., is of great assistance in examining the cornea, iris, and lens. Demonstrating ophthalmoscopes are also made, but need not be described. Fig. 30.