This book is an introduction to the basic principles of electrical engineering, aimed at students and practitioners in the field. It covers topics such as electric circuits, electromagnetic fields, and electrical measurements, and provides practical advice on the use of measuring instruments and the interpretation of data. The authors, Arthur Edwin Kennelly and H. D. Wilkinson, were both prominent electrical engineers and educators in the early 20th century. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.