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Showing: 1-10 results of 59

CHAPTER I. STATESMANSHIP IN ITS RELATION TO WAR. Under this head are included those considerations from which a statesman concludes whether a war is proper, opportune, or indispensable, and determines the various operations necessary to attain the object of the war. A government goes to war,— To reclaim certain rights or to defend them; To protect and maintain the great interests of the state, as commerce, manufactures, or... 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 MEN BEHIND THE MACHINES I MACHINES. AS SEEN FROM A MEADOW It would be difficult to find anything in the encyclopedia that would justify the claim that we are about to make, or anything in the dictionary. Even a poem—which is supposed to prove anything with a little of nothing—could hardly be found to prove it; but in this beginning hour of the twentieth century there are not a few of us—for the time at least allowed to... more...

Robert Fulton. This story is about a giant. Do you believe in them? He peeps out of your coffee cup in the morning. He cheers you upon a cold day in winter. But the boys and girls were not so well acquainted with him a hundred years ago. About that long ago, far to the north and east, a queer boy lived. He sat in his grandmother's kitchen many an hour, watching the tea-kettle. He seemed to be idle. But he was really very busy. He was... more...


DEFINITIONS DEFIN. I. By the Rays of Light I understand its least Parts, and those as well Successive in the same Lines, as Contemporary in several Lines. For it is manifest that Light consists of Parts, both Successive and Contemporary; because in the same place you may stop that which comes one moment, and let pass that which comes presently after; and in the same time you may stop it in any one place, and let it pass in any other. For that... more...

PREFACE To a good many of us the inventor is the true hero for he multiplies the working value of life. He performs an old task with new economy, as when he devises a mowing-machine to oust the scythe; or he creates a service wholly new, as when he bids a landscape depict itself on a photographic plate. He, and his twin brother, the discoverer, have eyes to read a lesson that Nature has held for ages under the undiscerning gaze of other men.... more...

APPARATUS 1. 1. Carbon-Zinc Cell. Fig. 1. If you have some rubber bands you can quickly make a cell out of rods of zinc and carbon. The rods are kept apart by putting a band, B, around each end of both rods. The bare wires are pinched under the upper bands. The whole is then bound together by means of the bands, A, and placed in a tumbler of fluid, as given in . This method does not make first-class connections between the wire and rods. ()... 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...

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...