Excerpt from The Principles of Dynamo Electric Machinery As an illustration of what may happen if the mathematics Of electrical engineering is taught before a physical conception of the actions which take place has been acquired, the writer may cite the case Of a student who recently came to him for an examina tion. The young man reproduced very well several pages of mathematical demonstrations relating to transformers, and all would have been well had t a chance question revealed the fact that he believed all the time that the function Of the trans former was to step up or step down the voltage of a continuous current circuit. This is by means an isolated case. There are many others nearly as bad. The scope of the book is such as to teach the student two things about each machine studied: first, what the machine will do; second, why it does it. NO attempt is made to take up questions relating to the design of electrical machinery. 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 techlogy 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.