An elementary treatise on the function of vision and its anomalies / by Dr. Giraud-Teulon ; translated from the second French edition by Lloyd Owen.

  • Owen Lloyd.
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: An elementary treatise on the function of vision and its anomalies / by Dr. Giraud-Teulon ; translated from the second French edition by Lloyd Owen. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    of changing the direction of the rays which pass through them, by making them, at their emergence, to incline towards the base of the prism. By this means the retinal or sensorial projection is thrown on the side Fig. 9. of the refracting angle of the glass, in such a manner, that for a given position (A) of an object, there follows, according to the kind of prism, either a convergence of the optic axes to a more distant point (B) (see fig- 9); or, on the other hand, if the position of the refracting angle of the prism be reversed, a convergence to a point nearer than that at which the object actually