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Showing: 31-40 results of 59

The year 1913 marks the close of the first fifty years since Abraham Lincoln issued that famous edict known as the emancipation proclamation, by which physical freedom was vouchsafed to the slaves and the descendants of slaves in this country. And it would seem entirely fit and proper that those who were either directly or indirectly benefited by that proclamation should pause long enough at this period in their national life to review the past,... more...

CHAPTER I. THE POWER OF THE AIR. "That's it, Jack. Let her out!" "Suffering speed laws of Squantum, but she can travel!" exclaimed Dick Donovan, redheaded and voluble. "I tell you, electricity is the thing. Beats gasoline a million ways," chimed in Tom Jesson. Tom sat beside his cousin, Jack Chadwick, on the driver's seat of a curious-looking automobile which was whizzing down the smooth, broad, green-bordered road that led to Nestorville,... more...

CHAPTER I. THE INCEPTION OF THE GRANGE When President Johnson authorized the Commissioner of Agriculture, in 1866, to send a clerk in his bureau on a trip through the Southern States to procure "statistical and other information from those States," he could scarcely have foreseen that this trip would lead to a movement among the farmers, which, in varying forms, would affect the political and economic life of the nation for half a century. The... more...

INTRODUCTION Any ordinary, active man, provided he has reasonably good eyesight and nerve, can fly, and fly well. If he has nerve enough to drive an automobile through the streets of a large city, and perhaps argue with a policeman on the question of speed limits, he can take himself off the ground in an airplane, and also land—a thing vastly more difficult and dangerous. We hear a great deal about special tests for the... more...

Depth of Soil for Fruit. Would four feet of good loose soil be enough for lemons? Four feet of good soil, providing the underlying strata are not charged with alkali, would give you a good growth of lemon trees if moisture was regularly present in about the right quantity, neither too much nor too little, and the temperature conditions were favorable to the success of this tree, which will not stand as much frost as the orange. Temperatures... more...


INTRODUCTION THE Germans interpret their new national colours—black, red, and white—by the saying, "Durch Nacht und Blut zur licht." ("Through night and blood to light"), and no work yet written conveys to the thinker a clearer conception of all that the red streak in their flag stands for than this deep and philosophical analysis of "War" by Clausewitz. It reveals "War," stripped of all accessories, as the exercise of force for the... more...

I COMMUNICATION AMONG THE ANCIENTS     Signaling the Fall of Troy—Marine Signaling among the    Argonauts—Couriers of the Greeks, Romans, and    Aztecs—Sound-signaling—Stentorophonic Tube—The Shouting    Sentinels—The Clepsydra—Signal Columns—Indian Fire and Smoke    Signals. It was very early in... more...

ELECTRICITY AND MATTER My Dear Son: You are interested in radio-telephony and want me to explain it to you. I’ll do so in the shortest and easiest way which I can devise. The explanation will be the simplest which I can give and still make it possible for you to build and operate your own set and to understand the operation of the large commercial sets to which you will listen. I’ll write you a series of letters which will contain... more...

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...