ELECTRICIAN'S HANDY BOOK A MODERN BOOK OF REFERENCE A condensed cyclopedia of electricity, more exhaustive than an A reference book for the advanced electrician and a text book BY T. O'CONOR SLOANE, A. M., E. M., Ph.D. "Arithmetic of Electricity," "Standard Electrical Dictionary," Etc. SCIENCE FIFTH REVISED AND ENLARGED EDITION Illustrated by over 600 illustrations and diagrams NEW YORK THE NORMAN W. HENLEY PUBLISHING CO. 2 WEST 45TH STREET Also entered at Stationers' Hall Court, London, England All Rights Reserved PRINTED IN U. S. A. Composition, Electrotyping and Press Work B PREFACE TO THE FIFTH EDITION. The Electricians' Handy Book has met with such favor from its readers in the past that it is hoped that a new and enlarged edition will meet with the same kind reception. Since it first appeared many changes have taken place in the electrical field, and it is believed that the new matter in the work covers the field of new discovery and development. The present work is rather practical than theoretical; the abstruse theories of the subjects treated in it are not within its scope. The work of treating the whole immense field of electrical engineering from early days to the present time would certainly be an endless one; the work of writing the present book has been lightened by the fact that the progress of electrical science in its practical aspect has been in the direction of the survival of the fittest. This tendency has had the effect of removing from the field of engineering many most ingenious devices, whose consignment to oblivion might be a subject for regret. But this disappearance of the old makes the amount to be described and learned less, and thereby lightens the labor of author and student. It is fair to say that the development of electrical engineering is largely in the direction of simplification. In early days results inferior to those attained in the present era were secured by the use of apparatus more elaborate than that which is now employed. The evils of complication have long been recognized, and the trend of invention has been to avoid it. One of the earliest objects of the inventor was the production of an arc lamp without mechanism; the results of these efforts have completely disappeared from view, and the simplified mechanical arc lamps of the present day are their successors. The same history can be traced for other branches of the science. Quantities of the most ingenious inventions are no longer in use, as better machinery has taken their places. For electrical engineering is nothing if not practical, and sentiment has no part in dictating what shall survive and what shall be forgotten. Something remains to be done in the elucidation of the theory. The very name of the science has never been adequately defined, although the working theory has been developed to a high degree of perfection. The greater general familiarity with the mere names of things electrical makes the subject seem less mysterious than formerly, when the words "ampere," "volt," and the like were rarely heard outside of a college. This should not induce the student to feel that his path is any shorter than was that of his predecessors. It is a much longer one, made a little easier by the fact that it is now a better-marked one. But he has more to learn than had his predecessors, and it must be more exactly learned. The modern science cannot be trifled with. This book is sent on its way with the fullest sense of the difficulties involved in its preparation. In its writing the literature of the science and the classics of engineering literature have been freely used. The author's thanks are also due to many friends for assistance most kindly rendered. OCTOBER, 1919 CONTENTS. Electrical Calculations-Algebra-Direct and Inverse Proportion- Percentage-Fractions-Compound Fractions-Inverted Addition and Subtraction-Multiplication and Division-Squares of Numbers-Cancela- tion-Powers of Ten or Exponential Notation-Logarithms-Angular Measurements-Radian System of Angular Measurement-Trigonometric Functions-Numerical Values of Circular Functions-Greek Letters- Useful Constants-Torque-The Dynamometer-The Prony Brake-Lumi- Electric Quantity-Storage of Electric Quantity-Condensers-Charg- ing-Meaning of Quantity of Electricity-Earthing a Condenser-Capa- city of Condensers-Single Surface Condensers-Unit of Quantity-The Storage of Quantity of Electricity-Capacity-Dielectrics-Specific In- ductive Capacity or Inductivity-Examples of Capacity-Microfarad- Current and Rate Units-Conductors and Non-Conductors-Ether Waves Produced by Electricity-Action of a Conductor-Time Required to Pro- duce a Current-Production of Current-Current, Amperes, and Coulombs -Current Strength or Intensity-Analogy for the Ampere-Speed of a Current-Arrival Curve-Direction of a Current Memoria Technica Field of Force and Lines of Force Due to Current-Electromotive Force -Production of Electromotive Force-Dynamic and Static Electricity- Electromotive Force and Energy- -Conservation of Electricity-Electro- motive Force and the Static Charge-Electromotive Force in Thunder Clouds-Electromotive Force the Cause of Current-Drop of Potential— Analogies of Drop of Potential-Electromotive Force and Difference of The Electric Circuit-Constitution of a Circuit-Condensers in a Cir- cuit-Open and Closed Circuits-Circuits Without Appliances-Appli- ances and Generators in Circuits-Electrolytic Conductors-Actions of a Circuit-Parallel and Shunt-Series-Series Multiple-Multiple Series- Series and Parallel-Outer Circuit-Short Circuit-Conductibility, Con- ductance, and Conductivity-Resistance-Resistance and Energy-The Ohm-Internal and External Resistance-Circuit Without Resistance- |