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  • Early Telegraph and Electrical Manufacturers
    An early list of telegraph and electrical manufacturers T hose who have had the good fortune to come into possession of an early make of telegraph relay, sounder or key are, in many instances, at a loss in trying to establish the date of manufacture of their prize While, in most cases, the instrument bears the name of the manufacturer, there is no clue as to the year in which it was made
  • Telegraph-History
    When the Telegraph Came to California Two articles by James Gamble from The Californian magazine, 1881 : Early Reminiscences of the Telegraph on the Pacific Coast The first telegraph lines in California
  • Submarine communications cable - Wikipedia
    A submarine communications cable is a cable laid on the sea bed between land-based stations to carry telecommunication signals across stretches of ocean and sea The first submarine communications cables laid beginning in the 1850s carried telegraphy traffic, establishing the first instant telecommunications links between continents, such as the first transatlantic telegraph cable which became
  • Insulator (electricity) - Wikipedia
    An electrical insulator is a material whose internal electric charges do not flow freely; very little electric current will flow through it under the influence of an electric field This contrasts with other materials, semiconductors and conductors, which conduct electric current more easily The property that distinguishes an insulator is its resistivity; insulators have higher resistivity than
    PART I 50 THE ORIGINAL MORSE TELEGRAPH KEY was actually a notched piece of metal called a Portrule It was pulled along and the parts of the metal that were not notched made contact with another piece of metal, completed the electrical circuit, and produced the dots and dashes of the Morse Code
  • The Telegraph Office -- A Tribute to Morse Telegraphy and . . .
    Welcome to The Telegraph Office Whether you are a collector, historian or have a casual interest in the many facets of wire and wireless telegraphy, you will find something of interest here
    80 CIVIL WAR ERA PHELPS CAMELBACK KOB, Marked G M PHELPS-MAKER :(27KB) These Phelps Camelback keys were the most widely used of the Civil War keys Camelback keys have an upward lump like a camel's hump on the lever between the knob and the pivot
  • History of the Telephone | From The 1880s To Current Time
    Today, we take telephones for granted You probably have a telephone within arm’s reach as you read this But just over 100 years ago, the idea of instantly chatting to someone anywhere in the world seemed impossible

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