Page 38 - Miracle in the Eye

MIRACLE IN THE EYE

(Figure 1.11).
The iris, which
controls the
amount of light
entering the
eye, and its
surrounding
muscles.

The amount of light entering the eye can be multiplied nearly thirty
times according to how wide the pupil is. The change in the amount of light
produced by a flash camera in 0.1 seconds, for example, causes the pupil to
instantly adjust its size and admit less light.
Upon light's entering the eye and hitting the retina, nerves transmit a
signal to the brain. The brain is not only informed of the light's existence, but
also of its intensity. It immediately sends back a response as to how far the
muscles around the pupil should expand or contract. The entire process of
communication, calculation, and functioning, is over in less than a second.
At first glance, the line of communication between the iris muscles and
the brain seems like a normal biological link in the body. But when analyzed

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