This book is designed as a text-book for amateurs, students, and others who wish to take up a systematic course of elementary electrical experiments at home or in school.

The student is advised to begin at the beginning, to perform the experiments in the order given, and to understand each step before proceeding. Certain principles and explanations necessarily precede the practical and perhaps more interesting applications of those principles.

In selecting the apparatus for the experiments in this book, the author has kept constantly in mind the fact that the average student will not buy the expensive pieces usually described in text-books.

The two hundred experiments given can be performed with simple, inexpensive apparatus; in fact, the student should make at least a part of his own apparatus.

For the benefit of those who wish to make their own apparatus, the author has given, throughout the work, explanations that will aid in the construction of certain pieces especially adapted to these experiments. For those who have the author's "How Two Boys Made Their Own Electrical Apparatus," constant references have been made to it as the "Apparatus Book," as this contains full details for making almost all kinds of simple apparatus needed in "The Study of Elementary Electricity and Magnetism by Experiment."

THOMAS M. ST. JOHN.

New York, April, 1900.

The Study of Elementary Electricity and
Magnetism by Experiment

The Study of Elementary Electricity and Magnetism by Experiment.