March 19, 2018

…. .- .–. .–. -.– / — — -. -.. .- -.– Or dit-dit-dit-dit dit-dah dit-dah-dah dit-dah-dah dah-dit-dah-dah/dah-dah dah-dah-dah dah-dit dah-dit-dit dit-dah dah-dit-dah-dah. That’s Morse code for “Happy Monday!” In a way, you could say this was how one text messaged in the mid-1800’s! Morse code is a system of sending messages that uses short and long sounds combined in various ways to represent letters, numerals, and other characters. A short sound is called a dit. A long sound is called a dah.

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International Morse Code uses short and long sounds, which are written out as dots and dashes. Credit: WORLD BOOK chart

The code is named for the American inventor and painter Samuel F. B. Morse, who, with Leonard Gale and Alfred Vail, patented the telegraph in 1840 in the United States. The credit for inventing the telegraph is also given to another set of researchers: Sir William Cooke and Sir Charles Wheatstone in the United Kingdom.

For use with the telegraph, Morse developed a code that assigned a set of dots and dashes to letters of the English language alphabet and allowed for the simple transmission of complex messages across telegraph lines. In 1843, Morse and Vail received funding from the U.S. Congress to set up and test their telegraph system between Washington, D.C., and nearby Baltimore, Maryland. On May 24, 1844, Morse sent the first telegraph message to Vail. It read, What hath God wrought?—a quote from the Book of Numbers in the Bible. This started the telecommunications revolution. By 1861, a telegraph line connected California with the eastern U.S. states, and a few years later, another crossed the Atlantic Ocean from the United States to Europe.

In those days, telegraph companies used American Morse Code to transmit telegrams by wire. An operator tapped out a message on a telegraph key, a switch that opened and closed an electric circuit. A receiving device at the other end of the circuit made clicking sounds and wrote dots and dashes on a paper tape. To understand the message, Morse code relies on precise intervals of time between dits and dahs (written as dots and dashes), between letters, and between words. Today, the telegraph and Morse code are used mostly in aerial and naval navigation.

International Morse Code was derived from American Morse Code for use by radio telegraphers. It is for all languages that use the Latin alphabet. Amateur and maritime radio operators still use this code regularly. Military and commercial operators may also use it when radio signals are too weak for other systems to work. In this code, a dah is three times as long as a dit. Between the sounds that represent a character, there is an interval of silence as long as one dit. Between letters are three such intervals; between words, there are seven. Other alphabet versions of Morse code include the Japanese Wabun Code and Korean SKATS.

July 16, 2013

—•— (Start message) The last telegram in the last country to maintain a national telegraph service was sent yesterday, closing a major chapter in the story of a system that dominated long-distance communication for more than 100 years. The final message, tapped out by Bharat Sanchar Nigram, India’s state-run telegram service, was transmitted 163 years after telegraph service was established in that country. The company said it could no longer compete profitably with Internet and cell phone messaging. Western Union ended its telegraph service in the United States in 2006. However, telegraph lines around the world have not been completely silenced. A Swiss-based company called Unitel Telegram Services reports transmitting tens of thousands of telegrams each month in more than 40 countries. According to the company, about half of its messages are sent to individuals, with businesses and diplomatic services accounting for the rest.

In an age of instant digital communication, it is difficult to appreciate the Earth-changing nature of the telegraph. Before the telegraph, most long-distance messages traveled no faster than the fastest horse. An exception was the semaphore method, in which a sequence of lights or other markers signaled from point to point. However, semaphore systems did not work well in bad weather. Even in good weather, they could transmit only a small amount of information.

Western Union messengers wait on scooters outside their office in 1940, ready for telegrams that need delivery. Western Union was the main provider of long-distance telegraph service in the United States from the mid-1800's until the early 2000's. (© American Stock/Getty Images)

The telegraph, which was an important means of communication from the mid-1800′s to the mid-1900′s, was the first instrument used to send messages by means of wires and electric current. Telegraph operators sent signals using a device that interrupted the flow of electric current along a wire. They used shorter and longer bursts of current, with spaces in between, to represent the letters of the message in what became known as Morse code. A device at the receiving end converted the signals to a series of clicks that a telegraph operator or a mechanical printer translated into words. The message was called a telegram if it was sent over wires stretched across land and a cablegram, or simply a cable, if it was sent through cables laid underwater.

The American painter and inventor Samuel F. B. Morse is credited with making the first practical telegraph in 1837. Morse received a U.S. patent for it in 1840. However, Morse’s invention built upon years of research and experiments by people who came before him. The text of Morse’s first telegram to his partner Alfred Vail was “What hath God Wrought?” •—•—•

Additional World Book articles:

• Signaling
• SOS
• Wheatstone, Sir Charles
• Woods, Granville T.
• Telecommunications (1924) (a Back in Time article)