. A treatise on the diseases of the eye. ating lines, and at their extremity are placed the figures I to XII, arrangedlike the figures on a watch dial. If the visual lines are parallel, the twocircles are fused into one image, in the centre of which lie the radiating stripesand at the circumference the figures. On account of the parallelism of theeyes, the latter are accommodated for their far point. By means of a screw,the circles are now removed further and further from the eyes, until all theradiating lines, except one, become indistinct. The direction of .this one iseasily identified by th
. A treatise on the diseases of the eye. ating lines, and at their extremity are placed the figures I to XII, arrangedlike the figures on a watch dial. If the visual lines are parallel, the twocircles are fused into one image, in the centre of which lie the radiating stripesand at the circumference the figures. On account of the parallelism of theeyes, the latter are accommodated for their far point. By means of a screw,the circles are now removed further and further from the eyes, until all theradiating lines, except one, become indistinct. The direction of .this one iseasily identified by the figures, and its direction corresponds to the diameterof the highest refraction. Behind the ocular lens of the one eye is arranged,upon a pivot, a series of concave cylindrical lenses, so that they can berapidly rotated in front of the eye until the lens is found which corrects theastigmatism and indicates its degree. These lenses are arranged in such a 1 FiWs Dobrmvolskys interesting paper on The different Changes of Astigmatismunder
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