INTRODUCTION This is the story of a great inventor, the most conspicuous figure of the age of electricity. The story is largely autobiography, for, through the author's association with Mr. Edison, it has been possible often to obtain his own narrative of his life. For nearly thirty-one years the author has had the privilege of a connection with Mr. Edison and the Edison companies, and at present he is acting as Mr. Edison's assistant. Every page of the book has been read by Mr. Edison himself, and it is published with his approval as the authoritative story of his life to the present time. It is probably as a worker of wonders, an interpreter of the secrets of Nature, an actual wizard of science, that Edison fascinates the imagination of almost every boy. In this picture of the actual facts of the inventor's life the reader will find that while Edison is just as great as imagined, yet this greatness has not been reached by chance, but honestly earned by the hardest kind of hard work and the most intense and earnest application. The wonderful things that he has accomplished have been the things that he purposely set out to do, and are not the result of some happy thought, or blind luck, or chance. There has been but little abatement in Mr. Edison's activities. The flight of time has not dimmed his vivid imagination; has brought no change to his clear broad mental vision; nor has his capacity for intensive, forceful work perceptibly lessened. There is no telling what other inventions he may yet make to benefit the world, but if he never added anything to what he has already done, his life and achievements afford the telling of one of the most remarkable stories in the history of the world. The author has had the honor and pleasure of assisting in the preparation of a large and comprehensive biography entitled, Edison: His Life and Inventions, by Frank L. Dyer and T. Commerford Martin, published by the publishers of the present volume. He gratefully acknowledges the fact that certain features of this book have been adapted from the pages of that elaborate biography. For the permission to do this he tenders his thanks to his friends Frank L. Dyer and the late T. Commerford Martin. WILLIAM H. MEADOWCROFT.