Technology & Engineering Books

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CHAPTER I. INTRODUCTION. Our distance from the old world, and the favorable circumstances in which we have been placed with respect to the other nations of the new world, have made it so easy for our government to adhere to a pacific policy, that, in the sixty-two years that have elapsed since the acknowledgment of our national independence, we have enjoyed more than fifty-eight of general peace; our... 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... 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 the history of the world that man began to feel the urgent need of... 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... more...

CHAPTER I. Man's Duel with Nature Of all man's great achievements none is, perhaps, more full of human interest than are those concerned with flight. We regard ourselves as remarkable beings, and our wonderful discoveries in science and invention induce us to believe we are far and away the cleverest of all the living creatures in the great scheme of Creation. And yet in the matter of flight... more...

ANNOUNCER In the year 1661 Connecticut received from the hand of Charles the Second a very liberal charter granting to the people of the colony almost complete self-government and to the colony an enormous stretch of territory extending westward to the Pacific Ocean. For fifteen years the colony prospered under the generous charter. Then in 1676 trouble arose with the Governor of New York, Sir Edmund... 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... 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... 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... more...

CHAPTER I. THE APPARATUS. To a proper comprehension of the succeeding chapters, it is necessary first of all to be familiar with the apparatus employed in carrying out electro-balneological treatment, and I therefore proceed to give a description of this. It may conveniently be divided as follows, viz. a. The tub; b. The electrodes and connections; c. The water; d. Chemicals; e. The batteries. (a) The... more...