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Elementary Science Education

Communication over long distances 

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    • #3817

      Bernard Nebel

      Prior to 1844, out of hearing or sight range, no message could travel faster than a horse; that is, a rider on a horse carrying a message from one location to the next. In the 1830s and early 1840s Samuel Morse and other inventors recognized that an electric current could be transmitted long distances over a wire and activate a buzzer at the other end. The problem was: How can a mono-tonal buzzer, which can only be turned on and off, be used to transmit words? (Have students wrestle with the problem.) Morse’s solution was to create a code in which sequences of short and long touches on the buzzer (known as dots and dashes) stood for the different letters and numbers. The first message that marked the beginning of the technological revolution of long distance communication was sent between Washington, DC and Baltimore in 1844. The following is brief video description of the event.

      The Morse Code itself is shown here: (Kids may like to learn it and send messages using flashlights.)

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