Morse Code History In 1836, Samuel Morse demonstrated the ability of a telegraph system to transmit information over wires. The information was sent as a series of electrical signals. Short signals are referred to as dits (represented as dots). Long signals are referred to as dahs (represented as dashes). With the advent of radio communications, an international version of Morse code became widely used. Try creating a Morse Code message The most well-known usage of Morse code is for sending the distress signal: SOS. The SOS signal is sent as: Morse code relies on precise intervals of time between dits and dahs, between letters, and between words. Here's a chart that shows these relationships:  dit  1 unit of time  dah  3 units of time  pause between letters  3 units of time  pause between words  7 units of time The speed of transmitting Morse code is measured in WPM (words per minute). The word "Paris" is used as the standard length of a word. To transmit the word "Paris" requires 50 units of time. If you transmitted the word "Paris" 5 times, you would be transmitting at 5 WPM. An experienced Morse code operator can transmit and receive information at 20-30 WPM. Samuel Morse Samuel Finley Breese Morse, (1791-1872), was a famous American inventor and painter. Morse graduated from Yale in 1810 and went on to study painting in England. In 1815, he took up portrait painting and was quite successful in this field. Morse helped to found the National Academy of Design and served as its first president. In 1827, Morse became interested in electricity. In 1832, he began a 12-year period perfecting his version of an electric telegraph, for which he subsequently received the first patent for this type of device. Samuel F. B. Morse (1791 - 1872) In 1844, Morse demonstrated to Congress the practicality of the telegraph by transmitting the famous message "What hath God wrought" over a wire from Washington to Baltimore. He later experimented with submarine cable telegraphy. Samuel  Morse Telegraph Receiver Used to receive the message, "What hath God wrought" during the demonstration to Congress in 1844. Smithsonian National Museum of American History Electric Telegraph The telegraph was the first device to send messages using electricity. Telegraph messages were sent by tapping out a special code for each letter of the message with a telegraph key. The telegraph changed the dots and dashes of this code into electrical impulses and transmitted them over telegraph wires. A telegraph receiver on the other end of the wire converted the electrical impulses to dots and dashes on a paper tape. Later, this code became universal and is now known as Morse Code. View the Morse Code Alphabet Telegraph Key Set Before electric telegraphy, most messages that traveled long distances were entrusted to messengers who memorized them or carried them in writing. These messages could be delivered no faster than the fastest horse. In the United States, the Morse telegraph was successful for a number of reasons, including its simple operation and its relatively low cost. By 1851, the country had over 50 telegraph companies though most telegraph business was controlled by the Magnetic Telegraph Company, which held the Morse patents. Top  |  Home  |  Information  |  Exhibits  |  Events Explore  |  Interactive Odyssey  |  Teachers Copyright © 2004 Odyssey Maritime Discovery Center