Excerpt from System of Diseases of the Eye, Vol. 4: By American, British, Dutch, French, German, and Spanish Authors; Motor Apparatus, Cornea, Lens, Refraction, Medical Ophthalmology It is true that the experiment with the accidental image requires, on the patient's part, intelligence and ability to observe correctly, upon which we cannot always depend in practice. It is, however, in connection with an examination of the field of excursions and some other symptoms with which we shall become acquainted, a most welcome aid when an exact diagnosis without the collaboration of the other eye is to be made. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.