maximum of information in a minimum space, but this information is so ingeniously arranged and correlated, and the 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 treats of the elements of electricity and magnetism, including a detailed description of primary and secondary batteries, and a full and complete discussion of the physical theory of the dynamo. As the subject matter here presented forms the groundwork of electrical engineering, every effort has been made to bring out those points that are essential and impress them on the mind by means of numerous examples and illustrations. The various electrical measurements have been given in an unusually clear manner, so that they can readily be understood and applied to every-day work, even by those who are not accustomed to making such measurements. Special attention has been paid to storage batteries, owing to their large and increasing use in connection with central stations, and primary batteries have been described much more fully than in ordinary textbooks. Besides being of great value to those making a specialty of electrical work, this volume will be found an excellent textbook by persons connected with electrical enterprises who wish to gain a general knowledge of electricity and magnetism.
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.
