The Cambridge Manuals of Science and
Literature
ELECTRICITY IN LOCOMOTION
CAMBRIDGE UNIVERSITY PRESS
London: FETTER LANE, E.C.
C. F. CLAY, MANAGER
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_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.
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
PAGE
PREFACE vi
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
CHAPTER I
THE WHEEL AND THE PUBLIC
One of the greatest of unknown men of genius was the inventor of the
wheel. Probably--as in the case of most inventions--he shares the
credit with others who prepared the way for him by discovering that
heavy weights could be more easily rolled than dragged. But, whatever
the origin of the wheel and axle, the combination was so admirable that
it remained unchanged in its essential features for centuries and still
forms the primary element in locomotion.
Some of the earliest forms of vehicle can be found co-existing with
the very latest. In Oporto, for instance, there are electric tramways,
but there are also ox wagons which seem to belong to the childhood of
the world. The wheels are rigidly fixed to rotating axles (the oldest
known arrangement) and the supports of both the front and the back
axles are rigidly fixed to the wagon. The result is that the vehicle
cannot 'steer' and must be dragged round corners. Some time ago the
authorities, realising at last that this dragging was ruinous to the
road surfaces, made a regulation that all wagons should have their
front axles pivoted. This attempt at improvement caused more agitation
than the Revolution itself. The owners of wagons argued--with perfect
justice--that the rigid wagon had served for innumerable generations;
and they refused, in the face of fines, to make the change. Their
resistance was so general and so dogged that the law became a dead
letter, and the people reverted with great content to the ancient
system which divided the business of local transport between yoked oxen
and women who had been trained from girlhood to carry heavy loads upon
their heads.
This example of conservatism, though extreme, is characteristic of
the attitude of the general public towards innovations in locomotion.
Until mechanical power came to be used, there was--for many
centuries--nothing which could be described as a radical innovation in
transport. Roads were multiplied and improved; some advance was made
in the design and construction of carriages; and the organisation of
posting and stage-coach services was developed. But little more was
done. Compared with these superficial changes, the idea of using steam
power on the highway or on a railroad was so drastic a change that
it roused tremendous opposition. The railway companies fought this
opposition and overcame it, but the use of steam carriages on ordinary
roads was postponed until the appearance of the petrol motor encouraged
a movement--once more against strong prejudice--for the repeal of the
legislation which restricted the use of mechanically-propelled vehicles
on the roads. In a similar way horse tramways were violently attacked;
and their conversion to electric traction was opposed by a determined
minority in every town. More recently, there was a vigorous agitation
against the substitution of motor omnibuses for horse omnibuses in
London and elsewhere.
To some extent this recurrent opposition was reasonable enough. The
new forms of locomotion had dangers of their own; they were generally
noisy and sometimes dirty; and occasionally, as in the case of early
tramways, they were a nuisance to existing traffic. But it may be noted
that electricity claims to provide a means of locomotion not only more
rapid and more efficient (in most cases) than any other, but free from
many of the drawbacks which gave conservatism an excuse for opposing
the introduction of steam and other forms of locomotion.
In the following pages I hope to give a clear account of the
achievements of electricity in the field of locomotion and also to
indicate some of its more immediate potentialities.