Entoptics, with its uses in physiology and medicine / by James Jago.

  • Jago James, 1815-1893.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: Entoptics, with its uses in physiology and medicine / by James Jago. 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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    ARTICLE PAGE 15. The refractions of the eye avoided, by placing the focus of the pencils at its optic centre ... ... ... ... 22 16. How to make obvious the relative distances of objects from the retina, by observing the parallaxes of their shadows in pairs of both pencils ... ... ... ... ... 23 17. How to do so by the lateral movement of the axis of the pencils 25 18. To do so by rotating the eye across the pencils ... ... 28 ,, Entoptical methods used by certain authors ... ... ... 28 19. The anterior focus of the eye. The effects of ocular refrac- tions upon the sizes of entoptical shadows ... ... ... 29 20. We may gain an insight into the character of entoptical objects, by observing how they obstruct, refract, or reflect light 30 21. Diffractive phenomena differ with opaque and transparent objects ... ... ... ... ... ... ... ... 22 22. Colour caused by diffraction at entoptical objects 35 CHAPTER III. APPARITIONS FROM EYELASHES, EYELIDS, AND CON- JUNCTIVAL FLUIDS. 23. Eyelashes reflect pencils of light from luminous discs into the eye ... ... ... ... ... ... ... 36 ,, And by inflecting light multiply their images ... ... 37 24. Tears are differently imaged in convergent and divergent pencils ... ... ... ... ... ... ■•• ••• 38 Phenomena produced by their refractive and diffractive actions ... ... ... ... ... ... ... ... 40 ,, By these actions, combined with diffractive by an eyelash ... 42 25. By the effects of pressure made upon the conjunctiva ... 43 „ Produced by reflection, diffraction, and reflection at the fluids gathered along the eyelids ... ... ... ... ib. 26. History of the entoptics of this chapter 48