Geometrical optics / by Val H. Mackinney and Harry L. Taylor.

  • Mackinney, Val H., 1791-1868.
Date:
1908
Catalogue details

Licence: In copyright

Credit: Geometrical optics / by Val H. Mackinney and Harry L. Taylor. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    12i WORKS ON OPTICS. HARTRIDGE—Refraction of the Eye The Ophthalmoscope KEYSTONE—'' The Optician's Manual ''The Optician's Manual Supplement' Skiascopy ... TAYLOR—The Manipulation and Fitting- of Ophthalmic Frames' THOMPSON— Optical Tables and Data LAURANCE—The Eye (Physiolog-ical and Anatomical) G-eneral and Practical Optics ... TAYLOR & MACKINNEY— The Key to Sight Testing- (2nd Edition) CHARTS FOR ADVERTISING PURPOSES. This Chart illustrates the relative value of vertical and horizontal lines in deciphering- letters, and provides a g-oocl means of explaining- to clients the sig-nificance of astigmatism. The first and second lines illustrate the differ- ence between a word having- the horizontal components of the letters blurred, and one in which the vertical positions are indistinct. In the third only vertical lines are shown, and in the fourth horizontal. 1/- each. A set of three charts, consisting- each of a series of tang-ents (at 10° intervals) to concentric circles. These charts are printed in black, red, and blue, and are delicate tests for irreg-ular astig-matism, besides illustrating- (by the different extent of the blurring) the chromatic aberration of the eye. 1/- each ; 2/6 the set of three. ASTICMMSM ASTICMAriSM Ar.litl^A!!:;:f^