Telegraph Network

“What hath God wrought”

On May 24, 1844, Samuel Morse sat in the chamber of the United States Supreme Court in Washington, D.C., and tapped out a message in the code that bears his name. At the other end of a wire that stretched 38 miles to Baltimore, his assistant Alfred Vail decoded the incoming clicks: “What hath God wrought,” a line from the Book of Numbers chosen by the daughter of the Commissioner of Patents. It was the first long-distance electrical telegraph message, and it marked the moment when information broke free from the speed of physical transport. Before the telegraph, a message could travel no faster than a horse, a ship, or a semaphore chain of signal towers. After the telegraph, information moved at nearly the speed of light. The transformation was so sudden and so total that Tom Standage, in his 1998 book The Victorian Internet, argued that the telegraph’s social impact was more disruptive than the modern internet — because the jump from horse speed to wire speed was proportionally far greater than the jump from telephone speed to fiber-optic speed.

The design of Morse code

Morse code is not an arbitrary assignment of dots and dashes to letters. Morse and Vail studied the type cases of a local newspaper to count how many of each letter a typical printing press carried. The most common letter in English, E, was assigned the shortest code: a single dot. T, the second most common, received a single dash. Rarer letters like Q (––.–) and Z (––..) received longer codes. This is an early example of what information theorists would later call variable-length coding — the same principle behind Huffman codes and modern data compression. By assigning shorter codes to more frequent symbols, Morse code minimizes the average transmission time per character, exactly as Shannon’s source coding theorem would later prove optimal. The practical effect was enormous: a skilled telegraph operator could send 20–30 words per minute, fast enough that the telegraph became commercially viable for everything from stock prices to love letters to war dispatches.

Relay stations and the continental network

Electrical signals weaken over distance as resistance in the wire dissipates energy. Early telegraph lines could only span about 20 miles before the signal became too faint to read. The solution was the relay: an electromagnet that used the incoming weak signal to close a switch, which in turn sent a fresh, strong signal along the next stretch of wire. This allowed telegraph networks to span continents by chaining relay stations every 15–20 miles. Each relay station was staffed by an operator who could also read the message, making every operator along the route a potential eavesdropper — a security concern that would feel familiar to anyone who has worried about internet intermediaries. The dream of crossing the Atlantic Ocean by telegraph was realized in 1858, when Cyrus Field’s submarine cable briefly connected Ireland to Newfoundland. That first cable failed after three weeks, but a permanent link was established in 1866, reducing the communication time between London and New York from ten days (by ship) to minutes. For the first time in human history, information traveled faster than any person could carry it, and the world began to shrink.