[Illustration] New York Thomas M. St. John 407 West 51st Street 1903 Copyright, 1900. By Thomas M. St. John. THINGS A BOY SHOULD KNOW ABOUT ELECTRICITY TABLE OF CONTENTS CHAPTER PAGE I. About Frictional Electricty 7 II. About Magnets and Magnetism 21 III. How Electricity is Generated by the Voltaic Cell, 32 IV. Various Voltaic Cells, 36 V. About Push-Buttons, Switches and Binding-Posts, 43 VI. Units and Apparatus for Electrical Measurements, 48 VII. Chemical Effects of the Electric Current, 58 VIII. How Electroplating and Electrotyping are Done, 60 IX. The Storage Battery, and How it Works, 63 X. How Electricity is Generated by Heat, 68 XI. Magnetic Effects of the Electric Current, 71 XII. How Electricity is Generated by Induction, 77 XIII. How the Induction Coil Works, 80 XIV. The Electric Telegraph, and How it Sends Messages, 84 XV. The Electric Bell and Some of its Uses, 91 XVI. The Telephone and How it Transmits Speech, 95 XVII. How Electricity is Generated by Dynamos, 101 XVIII. How the Electric Current is Transformed, 109 XIX. How Electric Currents are Distributed for Use, 114 XX. How Heat is Produced by the Electric Current, 124 XXI. How Light is Produced by the Incandescent Lamp, 129 XXII. How Light is Produced by the Arc Lamp, 135 XXIII. X-Rays, and How the Bones of the Human Body are Photographed, 141 XXIV. The Electric Motor, and How it Does Work, 147 XXV. Electric Cars, Boats and Automobiles, 154 XXVI. A Word About Central Stations, 162 XXVII. Miscellaneous Uses of Electricity, 165 TO THE READER For the benefit of those who wish to make their own electrical apparatus for experimental purposes, references have been made throughout this work to the "Apparatus Book;" by this is meant the author's "How Two Boys Made Their Own Electrical Apparatus." For those who wish to take up a course of elementary electrical experiments that can be performed with simple, home-made apparatus, references have been made to "Study;" by this is meant "The Study of Elementary Electricity and Magnetism by Experiment." THE AUTHOR. Things A Boy Should Know About Electricity CHAPTER I. ABOUT FRICTIONAL ELECTRICITY.