| Some good observations, allow me to deconstruct them :-) I did mention literacy as a prerequisite. I'll add another one - an alphabet. Both those are non-obvious, and took a looooong time to invent. (The Chinese writing system probably prevented them from inventing the printing press with movable type, simply because trying to cast several thousand letters was out of the question.) I'll add have you ever tried signalling with a mirror? I have (as a boy). It's really hard. The big problem is you don't know if the beam actually crossed the recipient's eye. About the best one could do is he sees a random flash now and then, not an organized system of timing sensitive flashes. Navy ships use signaling lamps, which solve that problem nicely, and they use Morse with it. Signaling towers were used in Europe before Morse, where different positions of levers were used for different letters. This system worked, but it was slow and very expensive, and didn't work at night. Morse actually came up with Morse code first, then tried to invent an electric telegraph system. His predecessors had come up with other various encoding schemes, but they were all impractical because they were too complicated for the primitive electric technology of the time. The point is, people had no trouble coming up with encoding schemes for the alphabet. Anyhow, see "The Victorian Internet" by Standage for an entertaining history of the topic. |