(3) 
there was no single work dealing with the question ina sufficiently comprehensive and yet practical 
manner to be of real use to the mechanical or mining engineer; either the treatment was adapted 
for specialists, or it was fragmentary, and power work was regarded as subservient to the question 
of lighting.. The Author has felt the want of such a book in dealing with his clients and others, 
and in ‘“‘ Etecrric Motive Power” has endeavoured to supply it. 
In the introduction the limiting conditions and essentials of a power plant are analysed, and 
in the subsequent chapters the power plant is treated synthetically. The dynamo, motor, line and 
details are discussed both as to function and design. The various systems of Kiger | 
and distributing power by continuous and alternate currents are fully enlarged upon, and muc! 
ractical information, gathered from actual experience, is distributed under the various divisions. 
The last two chapters deal exhaustively with the applications of electricity to mining work in 
Great Britain, the Continent and America, particularly with reference to collieries and coal- 
getting, and the results of the extensive experience eae. in this field are embodied. 
n general, the Author’s aim has been to give a sound digest of the theory and practice of 
the electrical transmission of power, which will be of real use to the practical engineer, and to 
avoid controversial points which lie in the province of the specialist, and elementary proofs which 
properly belong to text-books on electricity and magnetism. 
Soddy—RADIO-ACTIVITY : An Elementary Treatise from the 
Standpoint of the Disintegration Theory. By Fredk. Soddy, M.A. Fully Illustrated, and 
with a full Table of Contents and extended Index. 6s. 6d. nett. 
Extract fiom Author's Preface.—In this book the Author has attempted to give a con. 
nected account of the remarkable series of investigations which have followed M. Becquerel’s 
discovery in 1896 of a new property of the element Uranium. The discovery of this new pro- 
perty of self-radiance, or “‘radio-activity,” has proved to be the beginning of a new science, in 
the development of which physics and chemistry have played equal parts, but which, in the 
course of only eight years, has achieved an independent position, . . . Radio-activity has 
passed from the position of a descriptive to that of a thilosophical science, and in its main 
generalisations must exert a profound influence on almost every other branch of knowledge. 
It has been recognised that there is a vast and hitherto almost unsuspected store of energy bound 
in, and in some way associated with, the unit of elementary matter represented by the atom of 
Dalton. . . . Since the relations between energy and matter constitute the ultimate ground- 
work of every philosophical science, the influence of these generalisations on allied branches of 
knowledge is a matter of extreme interest at the present time. It would scem that they must 
effect sooner or later important changes in astronomy and cosmology, which have been long 
awaited by the biologist and geologist. 
he object of the book has been to give to Students and those interested in all departments 
of science a connected account of the main arguments and chief experimental data by which the 
results so far attained have been achieved. 
Wade—SECONDARY BATTERIES: THEIR MANUFACTURE 
AND USE. ByE. J. Wade. Nowready. por pages. 265 Illustrations. Price ros. 6d. nett. 
In this work the Author deals briefly with the Theory and very fully with the Chemistry, 
Design, Construction and Manufacture of Secondary Batteries or Accumulators. Prospectuses, 
post free, on application. 
he scope of Mr. Wade’s important work covers the whole class of apparatus embraced in 
the theory, construction and use of the secondary battery. The major portion of the book treats 
the accumulator purely from the point of view of an appliance which fulfils an important and 
definite purpose in electrical engineering practice, and whose manufacture, use and properties 
must be understood just as fully as those of a generator or a transformer. The concluding 
chapter (X.) aS a complete description of all modern electrical accumulators. The book 
contains 265 illustrations and a yery copious index: 
Weymouth—DRUM ARMATURES AND COMMUTATORS 
eee non PRACTICE). By F. Marten Weymouth. Fully Illustrated. Price 
7s. 6d. post free. 
Wilkinson—SUBMARINE CABLE-LAYING AND REPAIRING. 
By H. D. Wilkinson, M.I.E.E., &c. Over 400 pages and 200 specially drawn il i 
Price 12s. 6d. post free. Mew edition, September, rg04. v 2 Nepean ts 
This work describes the procedure on board ship when removing a fault or break ina 
submerged cable and the mechanical gear used in different vessels for this purpose; and considers 
the best and most recent practice as regards the electrical tests in use for the detection and 
localisation of faults, and the various difficulties that occur to the beginner. It gives a detailed 
technical summary of modern practice in Manufacturing, Laying, Testing and Repairing a Sub- 
marine Telegraph Cable. The testing section and details of boardship practice have been prepared 
with the object and hope of helping men in the cable services who are looking further into these 
branches.’ The description of the equipment of cable ships and the mechanical and electrical 
work carried on during the laying and repairing of a submarine cable will also prove to some 
not directly engaged in the profession, but nevertheless interested in the enterprise, a means of 
informing themselves as to the work which has to be done from the moment a new cable is 
projected until it is successfully laid and worked. 
“THE ELECTRICIAN” PRINTING & PUBLISHING CO., LTD., 
1,2 and 3, Salisbury Court, Fleet Street, London, E.C. 
