Excerpt from Electrical Installations, Vol. 1 of 4 The scientific student should go back to the early principles and master the old science, more especially as the correlation of physical units cannot be understood without a knowledge of the early theories. The succeeding volumes of this work deal in detail with actual practice in the great divisions of the subject. The English system of magnetic units has been used, but in the full treatment of dynamos and motors both that and c.g.s. Unit system shall be illustrated. 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.