The Cambridge Manuals of Science and Literature ELECTRICITY IN LOCOMOTION
LOCOMOTION AN ACCOUNT OF ITS MECHANISM, ITS ACHIEVEMENTS, AND ITS PROSPECTS BY ADAM GOWANS WHYTE, B.Sc. Editor of Electrical 11Idll.l'tri~s and Electrics Cambridge: at the University Press 1911
To EMILE GARCKE cambridge university press Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Tokyo, Mexico City Cambridge University Press The Edinburgh Building, Cambridge cb2 8ru, UK Published in the United States of America by Cambridge University Press, New York Information on this title: /9781107605985 Cambridge University Press 1911 First published 1911 First paperback edition 2011 A catalogue record for this publication is available from the British Library isbn 978-1-107-60598-5 Paperback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. With the exception of the coat of arms at the foot, the design on the title page is a reproduction of one used by the earliest known Cambridge printer, John Siberch, 1521
PREFACE IN the following pages an attempt is made to give a clear picture of the part which electricity has taken and will continue to take in the development of locomotion. Some of the aspects of electric traction are highly technical; others are purely financial. It is impossible to understand the achievements and possibilities of electricity in locomotion without a certain amount of discussion of both these points of view; but it is not necessary to go deeply into either in order to catch some of the enthusiasm which inspires the electrical engineer in his efforts to extend electric traction everywhere on road and rail. The hopes of electrical conquest extend, indeed, to locomotion on the sea and in the air as well as on the land. At the root of these hopes there lies a firm faith in the superior economies and flexibility of electricity as a mode of motion. In the explanations which are given of electric tramways, electric railways, electric automobiles, electric propulsion on ships, and the other phases of electric traction, nothing but the most elementary knowledge of electricity is presupposed. A certain amount of technical description is unavoidable, but I have restricted it as far as possible to essential matters which throw light upon the meaning of the various systems of electric traction and explain the economic and physical reasons for their adoption.
vi PREFACE Anyone who glances over the history of electric traction will be struck by the absence of outstanding names. There is no man who occupies the same position in the sphere of electric locomotion as Watt does in the world of steam, or Stephenson in the world of railways. As a pioneer, Dr Wernher von Siemens perhaps deserves more honour than any other. But the leading ideas embodied in electric traction systems were contributed by engineers who worked in the general field of electrical engineering; and they have been applied and developed by a numerous band of men who have added one brick of experience and ingenuity to another until the imposing structure was made visible to the world. Nevertheless, I hope the story as told briefly in the following chapters will not be found devoid of human interest. It has the advantage, at any rate, of the attraction which anything pertaining to electricity holds for all sections of the public. This attraction deepens upon closer acquaintance with the mechanism and the history of electricity in action; and if any of the descriptions and forecasts are found to be prejudiced in favour of a single instrument of locomotion, the fault may be considered to rest with the spell which electricity throws upon everyone who is concerned in any way with its applications in the service of man. I have to acknowledge the kind assistance of Mr Frank Broadbent, M.I.E.E., in looking over the proofs of this volume. A. G. W. 21 April 1911
CONTENTS PREFACE PAGE CHAP. I. The Wheel and the Public 1 II. Early Tramroads and Railways 4 III. The Birth of Electric Traction 12 IV. The Essential Advantages of Electric Traction on Tramways 19 V. The Mechanism of an Electric Tramcar : the Overhead System 29 VI. Conduit and Surface-Contact Tramway Systems. 37 VII. The Backwardness of Electric Traction in Great Britain 46 VIII. Electric Tramway Stagnation. The Trolley Omnibus 55 IX. Regenerative Control 67 X. Accumulator Electric Traction. The Electric Automobile 70 XI. Petrol-Electric Vehicles and main Marine Propulsion by Electricity 82 XII. The Pioneer Electric Railways 92 XIII. Electric Railways from the Engineering Point of View 107 XIV. Electric Traction on Main Line Railways...116 XV. Curiosities of Electric Traction 124 XVI. The Future....... 138 INDEX 142 vi