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A Treatise on the Shadow Test in its Practical Application to the Work of Refraction, with an Explanation in Detail of the Optical Principles on which the Science is Based.
This new work, the sale of which has already necessitated a second edition, far excels all previous treatises on the subject in comprehensiveness and practical value to the refractionist. It not only explains the test, but expounds fully and explicitly the principles underlying it—not only the phenomena revealed by the test, but the why and wherefore of such phenomena.
It contains a full description of skiascopic apparatus, including the latest and most approved instruments.
In depth of research, wealth of illustration and scientific completeness this work is unique.
Bound in cloth; contains 231 pages and 73 illustrations and colored plates.
Sent postpaid to any part of the world on receipt of $1.00 (4s. 2d.)
PUBLISHED BY THE KEYSTONE,
THE ORGAN OF THE JEWELRY AND OPTICAL TRADES,
19TH AND BROWN STS., PHILADELPHIA, U.S.A.
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Ocular Dioptrics—Functions of the Retina—Ocular Movements and Binocular Vision
Adjunct-Director of the Laboratory of Ophthalmology at the Sorbonne, Paris
BY CARL WEILAND, M.D.
Former Chief of Clinic in the Eye Department of the Jefferson College Hospital, Philadelphia, Pa.
This is the crowning work on physiologic optics, and will mark a new era in optical study. Its distinguished author is recognized in the world of science as the greatest living authority on this subject, and his book embodies not only his own researches, but those of the several hundred investigators who, in the past hundred years, made the eye their specialty and life study.
Tscherning has sifted the gold of all optical research from the dross, and his book, as now published in English with many additions, is the most valuable mine of reliable optical knowledge within reach of ophthalmologists. It contains 380 pages and 212 illustrations, and its reference list comprises the entire galaxy of scientists who have made the century famous in the world of optics.
The chapters on Ophthalmometry, Ophthalmoscopy, Accommodation, Astigmatism, Aberration and Entoptic Phenomena, etc.—in fact, the entire book contains so much that is new, practical and necessary that no refractionist can afford to be without it.
Bound in Cloth. 380 Pages, 212 Illustrations.