Science history: Samuel Morse dashes on the dot
Jeff Glorfeld looks back on the development of the electric telegraph.
Chances are you’re reading this on a hand-held device, probably a smartphone, something Americans call a cell phone and many people elsewhere refer to as a mobile phone.
That’s “phone”, abbreviated from the word telephone, defined in the Encyclopaedia Britannica as “an instrument designed for the simultaneous transmission and reception of the human voice”, from the Greek roots tele, or far, and phone, or sound.
Strange, then, that in a 2017 survey by Britain’s Daily Express newspaper, respondents said making calls from their phones – the original function of the mobile telephone – was the “least common” use, and 27% said they often went more than a week without using their phone to make calls.
Before the telephone, a common form of telecommunication was the telegraph.
John H. Lienhard, Professor Emeritus of Technology and Culture at the University of Houston, US, and author of a radio program titled Engines of Our Ingenuity, says “historians of technology are cautious about naming the first person to invent anything, because someone else has always thought up at least a part of it first”.
“The telegraph is no exception,” he adds. “The noted American painter Samuel FB Morse put together a telegraph system in 1837,” Lienhard says, “but the most original part of that system was the code that bears his name.”
So, Lienhard asks, how is it that Morse receives so much credit for inventing the telegraph?
“Well, for one thing, since he was American, he's the only telegraph inventor that American schools tell children about. But two other things were also important: Morse's code was the one that caught on. And, although few features of Morse's system were unique, taken together they were the right arrangement for a commercial success.”
As Lienhard notes, Morse was principally a painter: British and European trained and acclaimed for his works in the style of grand historical themes, although largely unappreciated in the US.
Scientists for many years had been studying electromagnetic energy and experimenting with its use as communications tools, many of which relied on multiple wires to carry signals.
Morse was convinced a single-wire electric telegraph could succeed. He obtained a US patent in 1838 and a $30,000 grant from the federal government in 1843 to build an experimental line between the cities of Baltimore and Washington, a distance of more than 60 kilometres. The first public message over Morse’s line was “What hath God wrought?”
Morse and his principal collaborator, Alfred Vail, developed their telegraph using electrical currents to control an electromagnet located at the receiving end of the telegraph wire.
According to an article in the New World Encyclopedia, their first telegraph, which went into operation in 1844, made indentations on a paper tape when an electrical current was transmitted.
When an electrical current was received, an electromagnet engaged an armature that pushed a stylus onto the moving paper tape, making an indentation on the paper. When the current was interrupted, the electromagnet retracted the stylus, and that portion of the moving paper remained unmarked.
The code includes the 26 English letters, A through Z, some non-English letters, Arabic numerals, and punctuation and procedural signals. No distinction is made between upper and lower cases.
Historian Tom Perera, in his History, Theory and Construction of the Electric Telegraph, brings us back to what John Lienhard says about being cautious about naming the first person to invent anything.
Perera says it was Vail who actually invented this system of assigning long and short voltages to different letters in the alphabet.
“He chose the length of the combination of short and long voltages according to the frequency of use of the particular letters as determined by reading and counting letter frequency in the local newspapers,” he says.
“For instance, he assigned a single short electrical pulse to the most frequently used letter in the English language, the letter E. For the less frequent letters he chose more complex combinations of short and long voltages.
“He assigned a specific combination of short and long voltages to each letter in the alphabet to form a code, which became known as the Morse Code, despite the fact that it had been invented by Alfred Vail.”