The telegraph used electric signals passed through a wire connecting two places to communicate messages. Direct current was switched on and off by the operator pressing and releasing a button called a telegraph key.
Developed by Morse and others in the 1830s the telegraph became widespread with cables connecting places around the globe and remained in use through to the latter part of the twentieth century. Commercially the telegraph companies charged by the word and so messages tended to be tersely worded and kept short using abbreviations and acronyms.
Samuel Finley Breese Morse was born on 27 April 1791 at Charlestown, Massachusetts, USA. He studied at Yale College and later trained in painting in England becoming a portrait artist.
Morse also had an interest in invention and the newly developing electricity. The first electric telegraph had been proposed in 1753 but was impractical because it used 26 wires, one for each letter. By the 1830's two German engineers had invented a five wire version using combinations for each letter but Morse realised that by using pulses of electricity to convey the information he could reduce the number of wires required to just one.
Did You Know?
The only Morse code most people know is the distress message SOS.
Morse code:
| . . . | S |
| - - - | O |
| . . . | S |
uses nine taps.
Multitap on a mobile phone:
| 6 6 6 6 | S |
| 7 7 7 | O |
| 6 6 6 6 | S |
uses eleven taps.
So much for a century and a half of progress!
Textra uses three.
Morse devised a system where each letter and number was represented by a different pattern of short and long pulses. He demonstrated a single wire telegraph using his dot and dash code at an exhibition in New York in 1838 and filed his patent soon afterwards.
Assisted by Federal funding Morse was able to show his device a practical means of communication with the first wire linking Baltimore to Washington DC. Private companies then spread Morse's telegraph throughout the United States with more than 20,000 miles of wire in operation by 1855.
Morse died of pneumonia on 2 April 1872 in New York.
US 1,647 "Improvement in the Mode of Communicating Information by Signals by the Application of Electro-Magnetism" 20 June 1840.
Click here to read the original patent
Did You Know?
The Morse Code
| A | . _ |
N | _ . |
| B | _ . . . |
O | _ _ _ |
| C | _ . _ . |
P | . _ _ . |
| D | _ . . |
Q | _ _ . _ |
| E | . |
R | . _ . |
| F | . . _ . |
S | . . . |
| G | _ _ . |
T | _ |
| H | . . . . |
U | . . _ |
| I | . . |
V | . . . _ |
| J | . _ _ _ |
W | . _ _ |
| K | _ . _ |
X | _ . . _ |
| L | . _ . . |
Y | _ . _ _ |
| M | _ _ |
Z | _ _ . . |
| 1 | . _ _ _ _ |
6 | _ . . . . |
| 2 | . . _ _ _ |
7 | _ _ . . . |
| 3 | . . . _ _ |
8 | _ _ _ . . |
| 4 | . . . . _ |
9 | _ _ _ _ . . |
| 5 | . . . . . |
0 | _ _ _ _ _ |
The Morse code allowed characters to be digitally encoded to be transmitted by telegraph.
The data entry device was a single button that when pressed connected electricity to the telegraph wire (ON) and when released disconnected it again (OFF). Different lengths of connection produced the two symbols the short dot . and the threefold longer dash -
Letters were made up of groups of between one and four symbols from A = dot-dash . - to Z = dash-dash-dot-dot - - . . The gaps between symbols are the same duration as a dot and between characters the same as a dash.
Numbers were groups of five symbols, 1 = . - - - -
Very little punctuation was supported, just comma, full-stop and question mark.
