AN ELEMENTARY TEXT-BOOK FOR THE USE OF SCHOOLS BY EDWARD R. SHAW, PH.D. DEAN OF SCHOOL OF PEDAGOGY, UNIVERSITY OF THE CITY OF NEW YORK FULLY ILLUSTRATED NEW YORK: MAYNARD, MERRILL, & Co., PUBLISHERS, 29, 31 & 33 EAST 19TH STREET. 1901 PREFACE. Purpose. This book is intended to lead pupils to acquire, by means of experiments, an elementary knowledge of Physics. It seeks to bring directly under the pupil's observation the reality itself, thus training him to observe for himself, to reason for himself, to rely upon himself, and to test the accuracy of his inferences and observations by new experiments, and by the comparison of his work with the work of others. Plan.-The book is inductive in its plan, yet it is not inductive to that rigid degree that a pupil must perform an experiment, and then make the inference without being told what to look for. The experiment is first performed, then comes the statement of the law involved. In performing the experiment, however, the pupil is guided by directions and questions. He must think; and, therefore, when he gives the statement of a principle, he has the knowledge of actual experience behind that statement. Individual Work. The book will be found to give large scope for individual work. Its method is believed to be in accord with Mr. Herbert Spencer's idea, that in education the process of self-development should be encouraged to the fullest extent. The plan of the book is such, that each pupil may gain his knowledge of the subject in that way of learning which is peculiar and natural to him, In other words, he comes into a knowledge of |