Stephenson 1996
https://web.archive.org/web/20151107094324/https://www.wired.com/1996/12/ffglass/
revisit Porthcurno Museum bit at the end -- glass tube of ink recording incoming signals, like the glass wires of fiber optic cable; clock mechanism similar to quartz clock in modern computer
"This is precisely the same function that is performed by the quartz clock chip at the heart of any modern computing device. The job performed by the regenerator/retransmitter is also perfectly recognizable to any modern digitally minded hacker tourist: it is an analog-to-digital converter. The analog voltages come down the cable into the device, the circuitry in the box decides whether the signal is a dot or a dash (or if you prefer, a 1 or a 0), and then an electromagnet physically moves one way or the other, depending on whether it’s a dot or a dash. At that moment, the device is strictly digital. The electromagnet, by moving, then closes a switch that generates a new pulse of analog voltage that moves on down the cable. The hacker tourist, who has spent much of his life messing around with invisible, ineffable bits, can hardly fail to be fascinated when staring into the guts of a machine built in 1927, steadily hammering out bits through an electromechanical process that can be seen and even touched."
"As I started to realize, and as John Worrall and many other cable-industry professionals subsequently told me, there have been new technologies but no new ideas since the turn of the century. Alas for Internet chauvinists who sneer at older, “analog” technology, this rule applies to the transmission of digital bits down wires, across long distances. We’ve been doing it ever since Morse sent “What hath God wrought!” from Washington to Baltimore."
"If you were to hum out a Morse code pattern of dots and dashes, all at middle C, a deaf observer watching the strings would notice a corresponding pattern of vibrations. If, at the same time, a second person was standing next to you humming an entirely different sequence of dots and dashes, but all on the musical tone of D, then a second deaf observer, watching the D strings, would be able to read that message, and so on for all the other tones on the scale. There would be no interference between the messages; each would come through as clearly as if it were the only message being sent. But anyone who wasn’t deaf would hear a cacophony of noise as all the message senders sang in different rhythms, on different notes. If you took this to an extreme, built a special piano with strings tuned as close to each other as possible, and trained the message senders to hum Morse code as fast as possible, the sound would merge into an insane roar of white noise."