THE NC-4 This historic airplane, the Navy-Curtiss No. 4 (known as the NC-4) completed the first transatlantic flight on May 31, 1919, by BY ROBERT ANDREWS MILLIKAN, PH.D., Sc.D. DIRECTOR OF THE NORMAN BRIDGE LABORATORY OF PHYSICS, PASADENA, CALIFORNIA AND HENRY GORDON GALE, PH.D. PROFESSOR OF PHYSICS IN THE UNIVERSITY OF CHICAGO BEING A REVISION OF THE AUTHORS' "A FIRST COURSE IN WILLARD R. PYLE, B.S. HEAD OF THE DEPARTMENT OF PHYSICS, MORRIS HIGH SCHOOL PREFACE The chief aim of this book in all of its editions has been to present elementary physics in such a way as to stimulate the pupil to do some thinking on his own account about the hows and whys of the physical world in which he lives. To this end such subjects, and only such subjects, have been included as touch most closely the everyday life of the average pupil. In a word, the endeavor has been to make this book represent the practical, everyday physics which the average person needs to help him to adjust himself to his surroundings and to interpret his own experiences correctly. But the conditions of modern life are changing at an astonishing rate and calling for the continuous revision of any text which would keep pace with them. For example, within the past ten years the internal-combustion engine has not only taken its place as an agent of equal importance with the steam engine in the world's industries but, what is more important, it has also come more fully into the daily life of the average man and woman than even the dynamo and motor have ever begun to do. The automobile is accordingly given fuller treatment in this new book than it has ever received before in any elementary physics text. Again, man's conquest of the air, after centuries of failure, is not only the most significant advance, on the practical side, of the twentieth century, but the airplane now attracts the attention and excites the interest of almost every man, woman, and child. Accordingly, the principles underlying this advance, and the methods by which it was brought about, find as full treatment in this volume as is consistent 557525 |