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Anonymous

"Watch and Clock Escapements A Complete Study in Theory and Practice of the Lever, Cylinder and Chronometer Escapements, Together with a Brief Account of the Origin and Evolution of the Escapement in Horology"


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.
* * * * *
PHYSIOLOGIC OPTICS
Ocular Dioptrics--Functions of the Retina--Ocular Movements and
Binocular Vision
BY DR.


Pages:
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