Excerpt from Rational Recreations, Vol. 2: In Which the Principles of Numbers and Natural Philosophy Are Clearly and Copiously Elucidated, by a Series of Easy, Entertaining, Interesting Experiments, Among Which Are All Those Commonly Performed With the Cards Fig. 1. Shows the manner in which the rays of light converge and diverge. Fig. 2. Different objects feen under the fame optic angle. Fig. 3. The refraction of a ray of light, ab, in pafling through different mediums. Fig. 4. The different forts of lenfes. 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.