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This self-portrait was made when Morse was only 21 years old

The Morse code

Samuel F. B. Morse (1791-1872) was not only a distinct scientist, but a skilled painter too (see his self-portrait on the right). In 1832, he conceived the idea of an electromagnetic telegraph, and built an experimental version in 1835. He did not construct a truly practical system until 1844, when the historic message, "What hath God wrought?" was successfully sent on a telegraph line from Washington to Baltimore.

The electric telegraph, as designed by Samuel Morse was basically an electrical circuit consisting of a battery, a key, and an electromagnet. The electromagnet had a pencil attached to it, which moved and made a mark on a paper tape whenever an electric current passed through it. The marks were long or short, depending on the amount of time the key was held down. A unique pattern was assigned to each character of the alphabet, as well as to the numerals an punctuation marks.

The Morse code used in those days differed greatly from that which we use today: the original users did not listen to tones but instead to the clicking sounds created by sounders. When sending a dahs, the user simply sent two rapid dits. They used the American Morse as opposed to today's International Morse Code.

There are two symbols used to represent letters in today's Morse code, called dots and dashes or dits and dahs. The length of the dit determines the speed at which the message is sent, and is used as the timing reference. A dah is conventionally 3 times as long as a dit and spacing between dahs and dits in a character is the length of one dit. Spacing between letters in a word is the length of a dah. Spacing between words is 7 dots.



The international Morse code:
A - J --- S 1 ---- Period   . --- Colon   : ---
B - K -- T - 2 --- Comma   , ---- Semicolon   ; ---
C -- L - U - 3 -- Question mark   ? -- Double dash   = --
D - M -- V - 4 - Apostrophe   ' ---- Fraction bar --
E N - W -- 5 Exclamation mark   ! ---- Hyphen   - --
F - O --- X -- 6 - Slash   / -- Underscore   _ -- -
G -- P -- Y --- 7 -- Parentheses open   ( --- Quotation mark   " --
H Q --- Z -- 8 --- Parentheses closed   ) ---- Dollar sign   $ --
I R - 0 -----9 ---- Ampersand   & At sign   @ ---

Non-English Morse code extensions:
, -- , --- -- ch ---- --
-- - g --- h --- j ---
---- , --- s - -- --

Telegraphy was a highly respected profession in the last century. Telegraph lines were built over longer and longer distances, installed predominantly along railroad lines for communication, to facilitate scheduling, control and safety. It soon began to connect newspapers with sources of news, which formerly were delayed for days or weeks by lack of rapid communication.

After the development of the first practical wireless telegraphic transmitters and receivers, long distance communication opened up tremendously. The invention of the telephone in the latter 1800's partially replaced telegraphy, but manual telegraphy is still very useful and may sometimes be imperative for safety.

Today, in our modern Western culture, telegraphy is almost altogether a hobby confined to the amateur radio world. But knowing the Morse code is still extremely useful in times of emergency, when a simple and efficient mode of communication is needed.