Page:Electrical Engineering Volume 2.djvu/11

Rh indexes are so full and complete, that it can at once be made available to the reader. The numerous examples and explanatory remarks, together with the absence of long demonstrations and abstruse mathematical calculations, are of great assistance in helping one to select the proper formula, method, or process and in teaching him how and when it should be used.

This volume gives an unusually clear explanation of the principles involved in the design of electrical machinery for direct and alternating currents, together with a detailed treatment of the theory of alternating currents and alternating-current apparatus. In presenting the latter subject the graphical method has been freely used, since it is more easily grasped and conveys a clearer idea of the principles involved than the analytical method. By using specially prepared diagrams and supplementing them by practical examples, this usually difficult subject is here made exceedingly simple without sacrificing thorough treatment. In connection with the design of electrical apparatus, all the fundamental principles and methods involved are given, and the manner of applying them fully illustrated. No attempt has been made to give data on a large number of machines, as such data soon becomes obsolete and, moreover, is of little use when applied to special cases.

As mentioned above, this volume is printed from the plates used in printing the Reference Libraries of the International Correspondence Schools. On account of the omission of certain papers, the material contained in which is given in better form elsewhere, there are several breaks in the continuity of the page numbers, formula numbers, article numbers, etc. This, however, does not impair the value of the volume, as the index has been reprinted and made to conform to the present arrangement.

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