The telegraph
Sending messages over wires in a code of dots and dashes. Samuel Morse sent the first message over a telegraph line in the United States in 1844.
Signals from the Brick Moon
Edward Everett Hale, “The Brick Moon,” part III, The Atlantic Monthly, December 1869 · December 1869 (the third part of a serial that ran October–December 1869)
I knew that at half past ten they would pass into the inevitable eclipse which struck them every night at this period of their orbit, and must, I thought, be a luxury to them, as recalling old memories of night when they were on this world. As they approached the line of shadow, some fifteen minutes before it was due, I counted on the edge thirty-seven specks arranged evidently in order; and, at one moment, as by one signal, all thirty-seven jumped into the air, — high jumps. Again they did it, and again. Then a low jump; then a high one. I caught the idea in a moment. They were telegraphing to our world, in the hope of an observer. Long leaps and short leaps, — the long and short of Morse’s Telegraph Alphabet, — were communicating ideas. My paper and pencil had been of course before me. I jotted down the despatch, whose language I knew perfectly: —
“Show ‘I understand’ on the Saw-Mill Flat.”
“Show ‘I understand’ on the Saw-Mill Flat.”
“Show ‘I understand’ on the Saw-Mill Flat.”
I knew that at half past ten they would pass into the inevitable eclipse which struck them every night at this period of their orbit, and must, I thought, be a luxury to them, as recalling old memories of night when they were on this world. As they approached the line of shadow, some fifteen minutes before it was due, I counted on the edge thirty-seven specks arranged evidently in order. And, at one moment, as by one signal, all thirty-seven jumped into the air — high jumps. Again they did it, and again. Then a low jump; then a high one. I caught the idea in a moment. They were telegraphing to our world, in the hope of an observer. Long leaps and short leaps — the long and short of Morse’s Telegraph Alphabet — were communicating ideas. My paper and pencil had been of course before me. I jotted down the despatch, whose language I knew perfectly: “Show ‘I understand’ on the Saw-Mill Flat.” “Show ‘I understand’ on the Saw-Mill Flat.” “Show ‘I understand’ on the Saw-Mill Flat.”