Samuel F. B. Morse (1791–1872) was a painter before he was an inventor. Born in Charlestown, Massachusetts, he studied art in London and painted portraits. In 1825, while he was in Washington painting a portrait, his wife died at home in New Haven; the letter bringing the news took days to reach him. Some writers link his later interest in fast messages to that loss.
Key idea
How the idea came
In 1832, sailing home from Europe on the ship Sully, Morse talked with a passenger, Charles Jackson, about electromagnets. Morse reasoned that if current could be sensed at any distance along a wire, signals could be sent. He sketched ideas in a notebook on the voyage.
What he tried, and who helped
Morse knew little science, and his first instrument worked only over short distances. Two people made the difference. Leonard Gale, a chemistry professor, showed him the work of the American scientist Joseph Henry, who had found how to wind electromagnets with many turns and use batteries of many cells so current could push through long wires. And Alfred Vail, a skilled mechanic, joined in 1837, built much better instruments, and helped shape the code. Historians still discuss how much of the dot-and-dash alphabet was Vail's.
The first code used numbers that stood for words in a code book. It was replaced by a code for letters. Common letters got short codes: E is a single dot, T a single dash. That makes messages faster, an idea used in data compression today.
| Letter | Code | Letter | Code |
|---|---|---|---|
| E | · | T | − |
| A | · − | N | − · |
| S | · · · | O | − − − |
| H | · · · · | R | · − · |
Worked example: Counting dot-lengths
- Three dots: $3 \times 1 = 3$ units.
- Two gaps between them: $2 \times 1 = 2$ units.
- $3 + 2 = 5$.
Answer: 5 units.
What hath God wrought
In 1843 Congress paid 30,000 dollars to build a test line from Washington to Baltimore, about 40 miles. On May 24, 1844, Morse sent the first official message from the Supreme Court chamber in the Capitol to Vail in Baltimore: "What hath God wrought." The words, from the Bible (Numbers 23:23), were chosen by Annie Ellsworth, the young daughter of a friend who had helped him.
Story or history?
Morse is often called the inventor of the telegraph. In Britain, William Cooke and Charles Wheatstone patented a needle telegraph in 1837 and had one working on a railway by 1839. Others built electric telegraphs too. Morse's system won in America and much of the world because it was simple, needed only one wire, and its code could be sent by ear and by hand.
| When | What happened |
|---|---|
| 1791 | Morse born in Charlestown, Massachusetts |
| 1831 | Joseph Henry demonstrates an electromagnet ringing a bell over a long wire |
| 1832 | Morse's idea aboard the Sully |
| 1837 | Alfred Vail joins; Cooke and Wheatstone patent their telegraph in Britain |
| 1840 | Morse receives a U.S. patent |
| 1843 | Congress funds the Washington–Baltimore line |
| 1844 | "What hath God wrought" |
| 1861 | Telegraph lines cross the United States |
| 1866 | A lasting telegraph cable crosses the Atlantic |
| 1872 | Morse dies in New York |
Worked example: Across the country
- $1861 - 1844 = 17$.
Answer: 17 years.
What it led to
The telegraph changed news, business and railways: trains could be scheduled safely, and news arrived the same day. Morse code was used by ships and radio operators for over a century. The telegraph's electromagnet relay, which lets a weak current switch a stronger one, is an ancestor of the switches inside computers.
Common mistake
Read more: Samuel Morse and Electrical telegraph.