Diseases of the eye / by Edward Nettleship ; with a supplement on examinations for color-blindness and acuity of vision and hearing, by William Thomson ; with 5 colored plates and 192 engravings.

  • Nettleship, Edward, 1845-1913.
Date:
1900
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the eye / by Edward Nettleship ; with a supplement on examinations for color-blindness and acuity of vision and hearing, by William Thomson ; with 5 colored plates and 192 engravings. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    PART I. MEANS OF DIAGNOSIS. The following abbreviations will be used in this work: Ace. Accommodation. p- Punctum proximum, As. Astigmatism. or near point. Ax. Axis of cylindrical Pr. Presbyopia. lenses. r. Punctum remotissi- B. Base of prism. sum,or far point. C. or Cyl. Cylindrical lens. S. or Sph Spherical lenses. D. Dioptre. T. Tension; Tn, normal E. Emmetropia. tension; + T, H. Hypermetropia. increased, and m. Metre; cm. centime- — T, dimin- tre ; mm. milli- ished tension. metre. V. Visual acuity. M. Myopia. y. s. Yellow spot of the 0. D. Optic disc. retina. CHAPTER I. OPTICAL OUTLINES. 1. Rays of light are deviated or refracted when they pass from one transparent medium, e. g., air, into another of different density, e. g., water or glass. 2. If the time occupied by light in passing through a given distance in air be taken as the time occupied in passing the