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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...

INTRODUCTORY Electricity, like every science, presents two phases to the student, one belonging to a theoretical knowledge, and the other which pertains to the practical application of that knowledge. The boy is directly interested in the practical use which he can make of this wonderful phenomenon in nature. It is, in reality, the most successful avenue by which he may obtain the theory, for he learns the abstract more readily from concrete... 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...

HOW NEWSPAPERS ARE MADE. We will suppose that it is a great newspaper, in a great city, printing daily 25,000, or more, copies. Here it is, with wide columns, with small, compact type, with very little space wasted in head lines, eight large pages of it, something like 100,000 words printed upon it, and sold for four cents—25,000 words for a cent. It is a great institution—a power greater than a hundred banking-houses, than a... 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...


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 Tub. This must be made of a... 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...

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 Andros, about the boundary line between the... 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...