Nearly every boy has experimented, at one time or another, with electricity and electrical apparatus, and whether it was with some of the simple frictional or galvanic toys, or with the more complicated induction-coils and motors, he has undoubtedly found it a most interesting amusement and an ever new and widening field for study. Then again, many boys would like to know something about simple electrical apparatus and how to make and use it. But his school-books relating to the general subject of electricity are hardly definite enough to serve as a practical manual. And yet there are many things in the way of electrical machinery and equipment that a boy can easily construct and use. In this book it is my purpose to show him just what can be done with the aid of the tools that are usually in his possession. While some things may have to be purchased from an electrical supply-house or other sources, there is still much material to be found about the house that may be put to good use by the amateur electrician.
It is not possible or desirable to describe every variety of electrical equipment. We must confine ourselves to apparatus which can be readily understood and operated. The “practical” idea is the one to be borne in mind. This book shows a boy how to use his brains and the simple tools and material that may be at his command. Care and thought in the construction of the apparatus are the important qualifications for success. The instructions are given in the clearest possible language; the diagrams and drawings are intelligible to any one who will take the trouble to study them. If your finished apparatus does not work properly, read the description again and see if you have not made some error. A misplaced or broken wire, a wrong connection, or a short circuit will mean all the difference between success and failure.
Save in one short chapter, static or frictional electricity (see Appendix) is not considered; for outside of laboratory experimenting and electro-medical apparatus, frictional electricity is but a toy--interesting and useful when generated in small volume, but very dangerous and difficult of control when in great volume. For example, the bolt of lightning is but the many times multiplied spark stored in the Leyden-jar by the static machine. For all practical purposes, galvanic electricity, in its various phases of direct and alternating current, meets the requirements of man. With the improved apparatus and the rapid advancement along the line of invention, electricity is as easily controlled to-day as steam--in fact, its economical use is even more fully under control and its adaptability more practical.