THE NC-4 This historic airplane, the Navy-Curtiss No. 4 (known as the NC-4) completed the first transatlantic fligh flying from Rockaway, Long Island, to Plymouth, England, a journey of 4513 miles on which five stops Her wing-spread is 126 ft., and her weight when manned and loaded was 14 tons. Lieutenant Comman Read of the United States Navy commanded her during the flight. Twenty United States destroyer intervals of about 70 miles along the route from Newfoundland to the Azores, the longest leg of the f BY ROBERT ANDREWS MILLIKAN, PH.D., Sc.D. PROFESSOR OF PHYSICS IN THE UNIVERSITY OF CHICAGO 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 The chief aim of this book in all of its editions has been present elementary physics in such a way as to stimulate t pupil to do some thinking on his own account about the ho and whys of the physical world in which he lives. To this e such subjects, and only such subjects, have been included touch most closely the everyday life of the average pupil. a word, the endeavor has been to make this book represe the practical, everyday physics which the average pers needs to help him to adjust himself to his surroundings a to interpret his own experiences correctly. But the conditions of modern life are changing at an asto ishing rate and calling for the continuous revision of any te which would keep pace with them. For example, within t past ten years the internal-combustion engine has not on taken its place as an agent of equal importance with t steam engine in the world's industries but, what is more i portant, it has also come more fully into the daily life of t average man and woman than even the dynamo and mot have ever begun to do. The automobile is accordingly giv fuller treatment in this new book than it has ever receiv before in any elementary physics text. Again, man's conquest of the air, after centuries of failur is not only the most significant advance, on the practical sid of the twentieth century, but the airplane now attracts t attention and excites the interest of almost every ma woman, and child. Accordingly, the principles underlyin this advance, and the methods by which it was broug about, find as full treatment in this volume as is consiste |