The Cure of Imperfect Sight by Treatment
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The Original Bates Method, for correcting vision defects

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24 Accepted Theory of Accommodation
Jesuit, Scheiner (1619). Later it was put forward by Descartes (1637). But the first definite evidence in sup port of the theory was presented by Dr. Thomas Young in a paper read before the Royal Society in 1800.1 "He adduced reasons," says Donders, "which, properly under-
Fig. 9. Diagrams of the Images of Purkinje
No. 1-Images of a candle: a, on the cornea; b, on the front of the lens; c, on the back of the lens.
No. 2.-Images of lights shining through rectangular openings in a screen while the eye is at rest (R) and during accommoda tion (A): a, on the cornea; b, on the front of the lens; c, on the back of the lens (after Helmholtz).
Note that in No. 2, A, the central images are smaller and have approached each other, a change which, if actually took place, would indicate an increase of curvature in the front of the lens during accommodation.
stood, should be taken as positive proofs."2 At the time, however, they attracted little attention.
About half a century later it occurred to Maximilian Langenbeck3 to seek light on the problem by the aid of
1  On the Mechanism of the Eye, Phil. Tr. Roy. Soc, London, 1801.
2  On the Anomalies of Accommodation and Refraction of the Eye, pp. 10-11.
5 Maximilian Adolf Langenbeck (1818-1877). Professor of anatomy, surgery and ophthalmology at Gottingen, from 1846 to 1851. Later settled in Hanover.