Our first century: being a popular descriptive portraiture of the one hundred great and memorable events of perpetual interest in the history of our country, political, military, mechanical, social, scientific and commercial: embracing also delineations of all the great historic characters celebrated in the annals of the republic; men of heroism, statesmanship, genius, oratory, adventure and philanthropy . t at long dis-tances it was supposed to be almostimpossible to obtain sufficient power forthe purpose, if it acted directly,—to over-come this difficulty, an auxiliary electro-magnet was emp
Our first century: being a popular descriptive portraiture of the one hundred great and memorable events of perpetual interest in the history of our country, political, military, mechanical, social, scientific and commercial: embracing also delineations of all the great historic characters celebrated in the annals of the republic; men of heroism, statesmanship, genius, oratory, adventure and philanthropy . t at long dis-tances it was supposed to be almostimpossible to obtain sufficient power forthe purpose, if it acted directly,—to over-come this difficulty, an auxiliary electro-magnet was employed. The electro-magnet which is directly in connection GREAT AND MEMORABLE EVENTS. 34^ with the telegraph wire is a small one,surrounded by about live hundred yardsor more of very fine wire, for the purjjoseof multiplying as much as possible theeffect of the feeble current that is trans-mitted. The soft-iron keeper, which isattracted by the magnet, is also very light,so that it may be the more readily highly sensitive instrument serves tomake and break contact with a local bat-tery, which brings into action a largeelectro-magnet, and as the local batteryand tlie magnet are close to the placewhere the work is to be done, any requiredforce may be easily- obtained. The batteries used are Groves zinc andplatinum, and two liquids ; any number ofthese mav be used. To form the electric. THE ORIGIXAL IXSTItlMEXT. circuit, one end of a copper wire is attachedto the end platina plate, and the otherend of the copper wire to the zinc wire is not required to run round allthe circuit—any metallic connection, suchas brass plates, etc., may form part of the practical working of the telegraph,—the battery with the ke_y attached, anda small table, being supposed, for example,to be at the Philadelphia station, and thetelegraph register to be at New York,—a wire runs from the platina plate up tothe metallic binding screw connection on the small table, and
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Keywords: ., bookcentury1800, bookdecade1870, bookpublishersprin, bookyear1876
