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Vision: its optical defects, and the adaptation of spectacles : embracing first, physical optics, second, physiological optics, third, errors of refraction and defects of accommodation, or optical defects of the eye : with seventy-four illustrations on wood and selections from the test-types of Jaeger and Snellen
Vision: its optical defects, and the adaptation of spectacles : embracing first, physical optics, second, physiological optics, third, errors of refraction and defects of accommodation, or optical defects of the eye : with seventy-four illustrations on wood and selections from the test-types of Jaeger and Snellen