American Morse code
Encyclopedia
Morse code
Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
developed in the mid-1840s, by Samuel Morse and Alfred Vail for their electric telegraph. The "American" qualifier was added because, after most of the rest of the world adopted "International Morse Code," the companies that continued to use the original Morse Code were mainly located in the United States. American Morse is now nearly extinct—it is most frequently seen in American railroad museums and American Civil War reenactment
American Civil War reenactment
American Civil War reenactment is an effort to recreate the appearance of a particular battle or other event associated with the American Civil War by hobbyists known as Civil War reenactors or Civil War recreationists...
s—and "Morse Code" today virtually always means the International Morse which supplanted American Morse.
History
American Morse Code was first used on a telegraph line constructed between Baltimore, MarylandMaryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, and the old Supreme Court chamber in the Capitol building in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
The first public message "What hath God wrought
What hath God wrought
"What hath God wrought" is a phrase from the Book of Numbers and may refer to:*"What hath God wrought", a message in American Morse code sent by Samuel F. B...
" was sent on May 24, 1844, by Morse in Washington to Alfred Vail at the Baltimore and Ohio Railroad
Baltimore and Ohio Railroad
The Baltimore and Ohio Railroad was one of the oldest railroads in the United States and the first common carrier railroad. It came into being mostly because the city of Baltimore wanted to compete with the newly constructed Erie Canal and another canal being proposed by Pennsylvania, which...
(B&O) "outer depot" (now the B&O Railroad Museum
B&O Railroad Museum
The B&O Railroad Museum is a museum exhibiting historic railroad equipment in Baltimore, Maryland, originally named the Baltimore & Ohio Transportation Museum when it opened on July 4, 1953. It has been called one of the most significant collections of railroad treasures in the world and has the...
) in Baltimore. The message is a Bible
Bible
The Bible refers to any one of the collections of the primary religious texts of Judaism and Christianity. There is no common version of the Bible, as the individual books , their contents and their order vary among denominations...
verse from Numbers
Book of Numbers
The Book of Numbers is the fourth book of the Hebrew Bible, and the fourth of five books of the Jewish Torah/Pentateuch....
23:23, chosen for Morse by Annie Ellsworth, daughter of the Governor of Connecticut. The original paper tape received by Vail in Baltimore is on display in the Library of Congress
Library of Congress
The Library of Congress is the research library of the United States Congress, de facto national library of the United States, and the oldest federal cultural institution in the United States. Located in three buildings in Washington, D.C., it is the largest library in the world by shelf space and...
in Washington, D.C.
In its original implementation, the Morse Code specification included the following:
- short mark or dot (·)
- longer mark or dash (—)
- intra-character gap (standard gap between the dots and dashes in a character)
- short gap (between letters)
- medium gap (between words)
- long gap (between sentences)
- long intra-character gap (longer internal gap used in C, O, R, Y, Z and &)
- "long dash" (——, the letter L)
- even longer dash (———, the numeral 0)
In the late 1890s, radio communication—initially known as "wireless telegraphy"—was invented, and used Morse Code transmissions. Most radio operators used the version of the Code that they were most familiar with—the American Morse Code in the United States, and Continental Morse in Europe. However, because of the long range of radio signals, a single international standard was needed, especially for seagoing vessels.
At the Radiotelegraphic Convention meeting in London in 1912, the section of the Convention covering "Transmission of Radiograms" included the statement that "The signals to be employed are those of Morse International Code." Even after this, the original Morse Code continued to be used throughout much of the United States. American Morse remained the standard for U.S. landline telegraph companies, including the dominant company, Western Union
Western Union
The Western Union Company is a financial services and communications company based in the United States. Its North American headquarters is in Englewood, Colorado. Up until 2006, Western Union was the best-known U.S...
, in part because the original code, with fewer dashes, could be sent about 5% faster than International Morse. American Morse also was commonly used for domestic radio transmissions on the Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...
, and along the Atlantic and Pacific coasts. However, International Morse predominated for ocean-going vessels, and many U.S. shipboard operators became skilled in transmitting both versions of the Code as needed.
Later Developments
Over time, with the disappearance of landline telegraphy, and the end of commercial radio use of Morse Code, American Morse has become nearly extinct in some states. In the United States, the ranks of amateur radio operators used to include many active and retired commercial landline telegraph operators, who preferred to use American Morse for their amateur radio transmissions, so the CWContinuous wave
A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...
(continuous wave) amateur bands used to have a mixture of American and International Morse. However, today even U.S. amateurs use International Morse almost exclusively.
Comparison of American (obsolete) and International Morse (by Gerke 1848)
Note: All links with the loudspeaker icon (
) are sound files for the international version of each symbol. See media help for assistance.| Letter | International Code |
American Morse |
Letter | International Code |
American Morse |
Digit | International Code |
American Morse |
|---|---|---|---|---|---|---|---|---|
| · — | — · | — — — — — | ——— | |||||
| — · · · | — — — | . _ . | · — — — — | · — — · | ||||
| — · — · | · · _ · | · — — · | · · · · · | · · — — — | · · — · · | |||
| — · · | — — · — | · · — · | · · · — — | · · · — · | ||||
| · | · — · | · _ · · | · · · · — | |||||
| · · — · | · — · | · · · | · · · · · | — — — | ||||
| — — · | — | — · · · · | · · · · · · | |||||
| · · · · | · · — | — — · · · | — — · · | |||||
| · · | · · · — | — — — · · | — · · · · | |||||
| · — — — | — · — · | · — — | — — — — · | — · · — | ||||
| — · — | — · · — | · — · · | ||||||
| · — · · | —— | — · — — | · · _ · · | |||||
| — — | — — · · | · · · _ · | ||||||
Common punctuation
| Symbol | International Code |
American Morse |
Symbol | International Code |
American Morse |
|---|---|---|---|---|---|
| Period [.] | · — · — · — | · · — — · · | Comma Comma A comma is a type of punctuation mark . The word comes from the Greek komma , which means something cut off or a short clause.Comma may also refer to:* Comma , a type of interval in music theory... [,] |
— — · · — — | · — · — |
| Question mark Question mark The question mark , is a punctuation mark that replaces the full stop at the end of an interrogative sentence in English and many other languages. The question mark is not used for indirect questions... [?] |
· · — — · · | — · · — · | Apostrophe ['] | · — — — — · | |
| Exclamation mark Exclamation mark The exclamation mark, exclamation point, or bang, or "dembanger" is a punctuation mark usually used after an interjection or exclamation to indicate strong feelings or high volume , and often marks the end of a sentence. Example: “Watch out!” The character is encoded in Unicode at... [!] |
— · — · — — | — — — · | Slash Slash (punctuation) The slash is a sign used as a punctuation mark and for various other purposes. It is now often called a forward slash , and many other alternative names.-History:... [/] |
— · · — · | |
| Parentheses | — · — — · — | Ampersand Ampersand An ampersand is a logogram representing the conjunction word "and". The symbol is a ligature of the letters in et, Latin for "and".-Etymology:... [&] |
· _ · · · | ||
| Colon Colon (punctuation) The colon is a punctuation mark consisting of two equally sized dots centered on the same vertical line.-Usage:A colon informs the reader that what follows the mark proves, explains, or lists elements of what preceded the mark.... [:] |
— — — · · · | Semicolon Semicolon The semicolon is a punctuation mark with several uses. The Italian printer Aldus Manutius the Elder established the practice of using the semicolon to separate words of opposed meaning and to indicate interdependent statements. "The first printed semicolon was the work of ... Aldus Manutius"... [;] |
— · — · — · | ||
| Double dash [=] | — · · · — | Fraction bar Fraction (mathematics) A fraction represents a part of a whole or, more generally, any number of equal parts. When spoken in everyday English, we specify how many parts of a certain size there are, for example, one-half, five-eighths and three-quarters.A common or "vulgar" fraction, such as 1/2, 5/8, 3/4, etc., consists... |
— · · — · | ||
| Hyphen Hyphen The hyphen is a punctuation mark used to join words and to separate syllables of a single word. The use of hyphens is called hyphenation. The hyphen should not be confused with dashes , which are longer and have different uses, or with the minus sign which is also longer... [-] |
— · · · · — | Underscore Underscore The underscore [ _ ] is a character that originally appeared on the typewriter and was primarily used to underline words... [_] |
· · — — · — | ||
| Quotation mark Quotation mark Quotation marks or inverted commas are punctuation marks at the beginning and end of a quotation, direct speech, literal title or name. Quotation marks can also be used to indicate a different meaning of a word or phrase than the one typically associated with it and are often used to express irony... ["] |
· — · · — · | Commat [@] | · — — · — · |
External links
- Samuel Morse's first "What hath God Wrought?" telegraph message, sent May 24, 1844 (American Morse recorded on a paper tape)
- Circa 1915 recording of an American Morse radio transmission
- Morse Telegraph Club, Inc.
- The Dot and Line Alphabet, a sketch from Edward Everett HaleEdward Everett HaleEdward Everett Hale was an American author, historian and Unitarian clergyman. He was a child prodigy who exhibited extraordinary literary skills and at age thirteen was enrolled at Harvard University where he graduated second in his class...
about (American) Morse code, first published 1858