This technical manual is an indispensable guide for anyone involved in the design or operation of electric railroads. The American Electric Railway Engineering Association provides detailed guidance on a wide range of topics, including track design, signaling and control systems, power systems, and rolling stock. This book is an essential reference work for engineers, technicians, and other professionals in the electric railroad industry. 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.