THEORIES OF TUITION Only eight years ago, in 1908, it was declared impossible for one man to teach another to fly. Those few men who had risen from the ground in aeroplanes, notably the Wright brothers, were held to be endowed by nature in some very peculiar way; to be men who possessed some remarkable and hitherto unexplained sense of equilibrium. That these men would be able to take other men—ordinary members of the human race—and... more...

In an inventive tour de force that seldom, if ever, has been equalled for its brilliance and far-reaching consequences, James Watt radically altered the steam engine not only by adding a separate condenser but by creating a whole new family of linkages. His approach was largely empirical, as we use the word today. This study suggests that, despite the glamor of today's sophisticated methods of calculation, a highly developed intuitive sense,... more...

THE STEAM-ENGINE. What is steam?—The mechanical energy of steam—The boiler—The circulation of water in a boiler—The enclosed furnace—The multitubular boiler—Fire-tube boilers—Other types of boilers—Aids to combustion—Boiler fittings—The safety-valve—The water-gauge—The steam-gauge—The water supply to a boiler. WHAT IS STEAM? If ice be heated above 32°... more...

THE FRANCO-AMERICAN CORPS It was on a cool, starlit evening, early in September, 1916, that I first met Drew of Massachusetts, and actually began my adventures as a prospective member of the Escadrille Américaine. We had sailed from New York by the same boat, had made our applications for enlistment in the Foreign Legion on the same day, without being aware of each other's existence; and in Paris, while waiting for our papers, we had... more...

Induction of Electric Currents. 6. About twenty-six feet of copper wire one twentieth of an inch in diameter were wound round a cylinder of wood as a helix, the different spires of which were prevented from touching by a thin interposed twine. This helix was covered with calico, and then a second wire applied in the same manner. In this way twelve helices were superposed, each containing an average length of wire of twenty-seven feet, and all in... more...

FOREWORD Once in awhile, maybe, twenty-five or thirty years ago, they used to pack you off during the holidays for a visit on Somebody's Farm. Have you forgotten? You went with your little round head close clipped till all the scar places showed white and you came back with a mat of sunbleached hair, your face and hands and legs brown as a nut. Probably you treasure recollections of those boyhood days when a raw field turnip, peeled with a... more...

DESCRIPTIVE CATALOGUE OF PLANTS. 1. Abelmoschus moschatus.—This plant is a native of Bengal. Its seeds were formerly mixed with hair powder, and are still used to perfume pomatum. The Arabs mix them with their coffee berries. In the West Indies the bruised seeds, steeped in rum, are used, both externally and internally, as a cure for snake bites. 2. Abrus precatorius.—Wild liquorice. This twining, leguminous plant is a native of... more...

INTRODUCTION Since the earliest communities of human beings first struggled for supremacy and protection, the principles of warfare have remained unchanged. New methods have been evolved and adopted with the progress of science, but no discovery, save perhaps that of gunpowder, has done so much in so short a time to revolutionize the conduct of war as aviation, the youngest, yet destined perhaps to be the most effective fighting-arm. Yet to-day... more...

PREFACE "Let posterity know, and knowing be astonished, that on the fifteenth day of September, 1784, Vincent Lunardi of Lucca, in Tuscany, the first aerial traveller in Britain, mounting from the Artillery Ground in London, and traversing the regions of the air for two hours and fifteen minutes, on this spot revisited the earth. In this rude monument for ages be recorded this wondrous enterprise successfully achieved by the powers of chemistry... more...

FOREWORD We are not tied to a desk or to a bench; we stay there only because we think we are tied. In Montana I had a horse, which was hobbled every night to keep him from wandering; that is, straps joined by a short chain were put around his forefeet, so that he could only hop. The hobbles were taken off in the morning, but he would still hop until he saw his mate trotting off. This book is intended to show how any one can trot off if he... more...