Excerpt from School Compendium of Natural and Experimental Philosophy: Embracing the Elementary Principles of Mechanics, Hydrostatics, Hydraulics, Pneumatics, Acoustics, Pyronomics, Optics, Electricity, Galvanism, Magnetism, Electro-Magnetism, Magneto-Electricity, and Astronomy Ten years have elapsed since this work first appeared in permanent form from the hands Of the stereotyper. During this time, the author has been gratified to learn that sixteen editions have been called for by the pub lic; but this gratification has been mingled with re gret that he has been unable from time to time to make such improvements as he knew were needed, and which the progress Of science, as well as a more extended ex perience, seemed imperiously to demand. He gladly avails himself Of the present Opportunity, afforded by the new publishers into Whose hands it has fallen, to make such improvements as in his Opinion will render it more worthy of the liberal patronage it has received; for although it is a long time since the author has had any pecuniary interest in the work, he hopes that it is not true that he has had no further solicitude. 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.