Merchant, F. W. (Francis Walter), 1855-1937, Chant, Clarence Augustus, 1865-1956 · Toronto : Copp Clark · leaf 370
ly objects at all distances varying from 8 or 10 inchesup to infinity. But, as we well know, there are many eyes withdefects, the chief of which are short-sightedness, long-sightedness, andastigmatism. A short-sighted eye cannot see objects at any considerable distancefrom the eye. The image of an… … Fig. 420.—In a short-sighted eye parallel rays convergeto a point hefore the retina; in a long-sighted eye,hehind the retina. observer it appears blurred. In a short-^sighted eye tlie len.s is toostrongly convergent, and in order to remedy this we must use spec-tacles producing the opposite effect,…
Physics
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