I just finished reading The Victorian Internet: The Remarkable Story of the Telegraph and the Nineteenth Century's Online Pioneers by Tom Standage. (I read most of it on my iPhone using the Kindle app.) The book was first published in 1998, and it's a great read about the development and impact of the telegraph. Of course, there are a lot of uncanny similarities between the development of the telegraph and that of the Internet. It's really interesting to imagine what living in a world before the telegraph must have been like: information could only travel as fast as a messenger on a horse, train, or steamship.
The book is not targeted at a technical audience and I was disappointed that there was not enough said about how messages got relayed through the telegraph network -- what was the routing protocol? There is some discussion of different signaling methods and Morse code, of course, as well as the many variations on Morse's telegraph design (including some really far-out designs that included multiplexing multiple operators over a single wire, essentially using TDMA to avoid conflicts).
There is some interesting discussion on the precursor to the electric telegraph, namely optical telegraphs, which amounted to networks of towers placed on hilltops using visual signals to convey information. These were fairly widespread in Europe in the 18th century and in some places it took a while for the electric telegraph to supplant them.
Some interesting tidbits are strewn throughout the book:
- A wide range of crazy schemes were devised to compress and encrypt information sent via telegraph, especially for business purposes. This caused problems for telegraph operators who were more prone to introducing errors when keying in unfamiliar strings of letters, and decreased the sending rate as well. At one point the ITU imposed a 15-letter limit on code words and required that they be composed of pronounceable syllables. This led to bogus code words like "APOGUMNOSOMETHA" (I am proud to report that Google offers zero results for this word -- I guess I just Googlewhacked it).
- There was a 19th century equivalent of the DNS: in Britain, individuals and companies could reserve a special "telegraphic address" that allowed others to send them a message without knowing their real, physical address. These were assigned on a first-come, first-served basis and each telegraph office had a giant book listing all of the addresses that had been registered.
- It took years for the telegraph to be recognized as anything other than a novelty. Morse and others struggled to convince the governments of US and Britain that they should invest in the development and deployment of the telegraph; early demonstrations did not convince U.S. Senators who (obviously) couldn't read strips of paper printed in Morse code.
- The original Transatlantic telegraph cable took years to complete, and broke four times while the ships were laying it out. It failed after only a few months of use.
- A period of fifty years elapsed between the development of the telegraph and the telephone.