The accomodation of the eye to distances / by William Clay Wallace.

  • Wallace, William Clay
Date:
1850
Catalogue details

Licence: Public Domain Mark

Credit: The accomodation of the eye to distances / by William Clay Wallace. 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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    ACCOMMODATION OF THE EYE TO DISTANCES. pencils of the organs of touch and taste become erect when excited. If; therefore, the power of motion is pos- sessed by one series of nervous filaments, it may likewise be granted to the fibres of the retina. In the cuttle fish the fibres of the optic nerve perforate the sieve-like lamina of pigment, the anterior surface of which is covered with an infinite number of separate retinas united into one, and each of these is supplied with a granule to receive the impression, and fibres to convey it to the sensorium. It is evident that if the fibres possess motion, they will be less impeded at the central foramen than at those por- tions of the retina where they are crowded over each other, and vision will be more distinct. Should the granular lamina follow the terminations of the fibres when the latte]- become excited, the central foramen, which is the only place where they are free, will advance, and ad- justment will be facilitated.
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