A Catechism of Familiar Things; - Their History, and the Events Which Led to Their Discovery. - With a Short Explanation of Some of the Principal Natural Phenomena. For the Use of Schools and Families. Enlarged and Revised Edition. by Anonymous
page 315 of 365 (86%)
page 315 of 365 (86%)
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An instrument invented by Sir David Brewster, consisting of a tube with slips of reflecting glass so arranged in the interior that small beads, bits of colored glass, and similar things are, by revolving the tube, thrown into an endless variety of beautiful shapes. CHAPTER XXI. ELECTRICITY, ELECTRIC CURRENTS, ELECTRIC BATTERY, ELECTROTYPING, STEREOTYPING, TELEGRAPH, OCEAN CABLE, LIGHTNING ROD, THE GULF STREAM, THE MT. CENIS TUNNEL, THE SUEZ CANAL, SUSPENSION BRIDGES, EMINENT AMERICANS. What is the nature of Electricity? A form of energy into which all other forms can readily be converted. What is an Electric current? Electricity manifests itself in a variety of ways, but all may be arranged under two heads, _viz._, 1, as a charge; 2, as a current. By means of friction, many bodies become electrified--that is, have acquired an electrical charge. If this charge is in great quantity we call it high tension. When a body containing an electrical charge is brought in contact with other bodies through which electricity is |
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