The term motor has a wider significance than any other word. A steam engine is a motor, and so, also, is a dynamo, a water wheel or a wind mill.
It would be just as descriptive to call a wind mill a wind motor, or a steam engine a steam motor, as to adhere to the old terms; and, on the other hand, since it would be out of place to call a dynamo or a wind mill an engine, the word motor seems best adapted to express the meaning of every type of mechanism which transforms energy into motion.
In considering the subject I shall proceed on the theory that the boy knows nothing whatsoever of the subject, nor the terms used to designate the various phases, subjects and elements. It must be elementary in its character, and wholly devoid of technical terms or sentences.
While it is necessary to give information in a book of this character, on the methods for figuring out power, it must be done without resorting to the formulas usually employed in engineering works, as they are of such a nature that the boy must have some knowledge of the higher mathematics to follow out the calculations employed.
Indeed, every phase should be brought within the mental view of the boy, and to do this may occasionally necessitate what might appear to be long drawn out explanations, all of which, it is hoped, will be the means of more clearly presenting the subject.
The opening chapters, which treat of the fundamentals, will be as nearly complete as possible, and thus lay a foundation for the work we shall be called upon to perform, when we treat of the structures of the different parts and devices in the various types of motors.
The object is to explain power in its various phases, how derived, and the manner in which advantage is taken of the elements, and substances with which we are brought into contact. The reasons for each step are plainly set forth with the view of teaching the boy what power means, rather than to instruct him how to make some particular part of the machinery.
The Inquisitive Trait.—My experience has impressed me with the universality of one trait in boys, namely, that of inquisitiveness. Put a machine before a boy and allow him to dissect it, and his curiosity will prompt him to question the motive for the particular construction of each part of its make-up.
The Reasons for Doing Things.—He is interested in knowing the reason why. Every boy has the spirit of the true investigator,—that quality which seeks to go behind or delve down deeply. This is a natural instinct.