Elementary Electricity. Book by William R. Wellman

PREFACE

This textbook has been especially prepared to assist in training stu-

dents in electrical theory on a secondary school level of instruction.

While almost all of the material should be adaptable to trade courses

and, in fact, should be helpful to any student of electricity, today's em-

phasis is on technical education, especially in electronics.

Recognizing that such technical students require a firm foundation in electrical principles, the author has attempted to prepare a book that would present those principles in an interesting fashion.

The text is supplemented by demonstrations that may be performed

by the instruetor or by individual students. Although such demonstra-

tions are numerous, the list is by no means complete and is intended

merely as a guide that can be extended by a resourceful teacher.

Many illustrations are included, both diagrammatic and photographie. Such

visual material should help the student to an understanding of the

utility of the equipment or apparatus that is described.

Some readers may question the author's judgment in omitting any

mention of radio in the chapter on communication.

This was a difficult decision to make, but the author has concluded that to present a reasonably complete discussion of such an extensive subject would result in an unwieldy book.

The author wishes to express his gratitude to the numerous electrical

manufacturers who cooperated by providing photographs of their

products.

February, 1959

W. R. W.