William Horatio Bates

“ Finding, as he states, "absolutely nothing but the ciliary muscle to which accommodation could be attributed,"19 Helmholtz concluded that the changes which he thought he had observed in the curvature of the lens must be effected by the action of this muscle; but he was unable to offer any satisfactory theory of the way it operated to produce these results, and he explicitly stated that the one he suggested possessed only the character of probability. ”

“ The fact that the eye is accommodated for near vision by an increase in the curvature of its crystalline lens, is, then, incontestably proved."11
Fig. 10. Diagram by Which Helmholtz Illustrated His Theory of Accommodation R is supposed to be the resting state of the lens, in which it is adjusted for distant vision. In A the suspensory ligament is supposed to have been relaxed through the contraction of the ciliary muscle, permitting the lens to bulge forward by virtue of its own elasticity. ”

“ Davis: Accommodation in the Lensless Eye, Reports of the Manhattan Eye and Ear Hospital, Jan., 1895. The article gives a review of the whole subject.
28. An instrument for measuring the curvature of the cornea.
29. Nov., 1893, p. 932.
30. Inasmuch as the eye is inextensible, it cannot adapt itself for the perception of objects situated at different distances by increasing the length of its axis, but only by increasing the refractive power of its lens. - De Schweinitz: Diseases of the Eye, eighth edition, 1916, pp. 35-36. ”

“ It might be due, he said, to the accommodative action of the iris, and possibly also to a lengthening of the visual axis through the action of the external muscles.23
For nearly three-quarters of a century the opinions of these masters have echoed through ophthalmological literature. ”

“ Davis therefore concluded that these tests were "wholly inadequate to decide the question at issue." During accommodation the ophthalmometer28 showed that the corneal curvature was changed and that the cornea moved forward a little. Under scopolamine, a drug sometimes used instead of atropine to paralyze the ciliary muscle (1/10 per cent solution every five minutes for thirty-five minutes, followed by a wait of half an hour) , these changes took place as before ”

“ Professor of anatomy, surgery and ophthalmology at Gottingen, from 1846 to 1851. Later settled in Hanover.
7. Johannes Evangelista von Purkinje (1787-1869) . Professor of physiology at Breslau and Prague, and the discoverer of many important physiological facts. ”