I just finished writing one book in a series set in the Napoleonic wars. One of the interesting things I found in doing research for it hits that lovely overlap between my professional interests and my fictional interests.
Both the English and the French used a visual telegraph system. Since there were only visual signals both sides called it “the telegraph”, but it depended on being able to see the next station in line. The French used a relatively uninteresting two armed semaphore system, but someone in England understood binary numbers in 1802. The English system used 6 panels which meant there were 64 (2^6) different symbols. Since there are 36 – 38 different letters and symbols that you might want to send (a-z, 0-9, and possibly . ,) that left a large space for abbreviations (message number 40 – ship), and channel control messages (Ok to send, Got it, wait, etc). Apparently messages could be sent across Britain in minutes rather than days, and the system was a critical, if largely forgotten, part of coastal defence.
The 1803 book “a picture of london for 1803″, available on google, states that the admiralty had two telegraph stations on the roof and for a tip you could go, have the system explained to you and watch the messages being sent and received. There are two conclusions that can be derived from this.
- The really did use the communications systems, but they didn’t have any concept of operational security. Anyone could come up and watch the process. Imagine just wandering into the Pentagon in the US, strolling down to the Naval operations systems center and watching the messages. Even worse, the chief coding officer would let you see how the messages are encoded.
- “for a tip”. Anyone from the street could wander around the Admiralty, and there was a more or less standardized bribe level to get to see what you wanted to see. There could have been no operational security, or if there was it involved skipping around the Admiralty and going directly to an officer on active duty.
Many books set in this period talk about “orders leaking”. Given the state of security in London, it would have been exceptional if the orders stayed secret. The level of jobbery or venality must have been amazing.