The Cambridge Manuals of Science and Literature ELECTRICITY IN LOCOMOTION CAMBRIDGE UNIVERSITY PRESS London: FETTER LANE, E.C. C. F. CLAY, MANAGER [Illustration] Edinburgh: 100, PRINCES STREET London: H. K. LEWIS, 136, GOWER STREET, W.C. Berlin: A. ASHER AND CO. Leipzig: F. A. BROCKHAUS New York: G. P. PUTNAM'S SONS Bombay and Calcutta: MACMILLAN AND CO., LTD. _All rights reserved_ ELECTRICITY IN LOCOMOTION AN ACCOUNT OF ITS MECHANISM, ITS ACHIEVEMENTS, AND ITS PROSPECTS BY ADAM GOWANS WHYTE, B.Sc. Editor of _Electrical Industries_ and _Electrics_ Cambridge: at the University Press 1911 TO EMILE GARCKE _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.