HELMHOLTZ'S THEORY OF ACCOMMODATION

Abstract

eir orginal popularity. The history of Helmholtz's theory of accommodation may be briefly stated as follows: As is well known the physical basis of the theory requires that the crystalline lens on accommodation for near objects should become both thicker and smaller in diameter. It is a deduction from the theory that the lens, wvhen removed from the eyeball should be in the fully accommodated state. Tscherning at first questioned every one of these statements, and, in the diagram published in his physiological optics, he showed neither a change in diameter nor in thickness. 1lany other ophthalmologists repeated Helmholtz's measurenments and confirmed them in practically every detail.