. The refraction of the eye; including a complete treatise on ophthalmometry; . 0°,converts the patients simple hypermetropic astigmatism intoa simple hypermetropia of 1 D. (see Fig. 76). The patient by means of his accommodative power cancorrect this simple hypermetropia (as produced by the minuscylinder) with comfort at times, because he can use the wholeof the ciliary muscle regularly ; while he could not correct thesimple hypermetropic astigmatism without discomfort, since,in that case, it must contract irregularly to act on the horizon-tal meridian of the lens without at the same time act
. The refraction of the eye; including a complete treatise on ophthalmometry; . 0°,converts the patients simple hypermetropic astigmatism intoa simple hypermetropia of 1 D. (see Fig. 76). The patient by means of his accommodative power cancorrect this simple hypermetropia (as produced by the minuscylinder) with comfort at times, because he can use the wholeof the ciliary muscle regularly ; while he could not correct thesimple hypermetropic astigmatism without discomfort, since,in that case, it must contract irregularly to act on the horizon-tal meridian of the lens without at the same time acting on the MIXED ASTIGMATISM 17^ vertical meridian, which is emmetropic and should be let is the simple explanation of these cases. No stronger-plea could be urged for the beginning of all tests with plusglasses, I am sure. To recapitulate : most cases of mixed astigmatism can becorrectly fitted with glasses without the use of a mydriatic,,provided that first, the amount and axis of the corneal astig-matism be ascertained; next, that the test for glasses be begun. Fig. 76.—(A) Before correction. (B) After correction with —ID cyl., 180°, hywhich the simple hypermetropic astigmatism is converted into a simple hyper-metropia of 1 D. with weak plus glasses and their strength gradually increased iand finally minus glasses tried. The chief indication for a mydriatic in such cases, as in allother cases of refractive error, is a spasm of means of detecting spasm of accommodation have alreadybeen pointed out elsewhere, so we need not consider them Case LXXIo 3Iixed astigmatism of large amount and withthe rule m each eye; Asthenopia; Relief ivitli glasses.—April -1. 180 THE refractio:n^ of the eye 1893, Miss S. A., aged twenty-two years, in good generalhealth, has had trouble with her eyes for the last six now complains of having to hold the print too close to hereyes when she reads, also of headache and pain in the eyesafter reading or sewi
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