Telegraph

The telegraph is a system of long distance communication that uses a pre-determined code to interpret electrical signals sent along wires from station to station. The system was developed some 40 years ago, but only in the last decade or so have connections between distant cities been possible, thanks to the invention of the undersea signalling cable and mass production of the large chemical batteries needed to send a recognizable signal through many miles of cabling.

Common uses

The telegraph is best used for relatively short messages. The most common code used for sending messages assigns each letter and number a unique assortment of long and short signals (written as dots and dashes), with operators spelling out the message one letter at a time. This process can be somewhat slow, as each the gaps between each long or short signal must be long enough for the detector in use at the other end to register the end of one signal and the beginning of the next. Several inventors are pursuing ideas that might lead to a more rapid-read signal detector, which could speed things up, but most operator pairs average no more than 40 signals per minute, which averages out to about 2 words per minute. A long message can take a whole workday to send, and may require multiple shifts for operators at each end as maintaining a constant signalling rate and keeping an accurate record of signals detected for hours is a mind numbing task.
Nevertheless, telegraphs have become a very popular way of sending messages throughout a city. Most large cities now have a robust network of telegraph stations for this purpose, often ensuring that a message can be sent by telegraph to within half a mile of its intended recipient, whereupon a runner at the station can quickly carry a written copy of the message to its intended destination. Some cities operate on a nodal network, with each station connected to several others; on such networks a message may need to be copied and transmitted several times before reaching the end of the line, with each station maintaining a reference of how to most efficiently send a message to any other station. Others, like Tulwood, use a hub-and-spoke design, with each station in the city connected to a central hub like the Tulwood Telegraph Building, ensuring that each message is sent and copied exactly twice. Intra-city telegraph service is now generally affordable enough to all but those with the most menial of jobs, and the contents of such messages range from professionals scheduling appointments and meetings to spouses asking their partners to stop at the market on their way home from work.
Inter-city and international signalling are much newer, but this form of communication allows rulers to stay in touch with envoys sent to distant lands. This has greatly improved their ability to manage relations with other realms, a change that sometimes improves relations between countries and sometimes has caused them to disintegrate. Nobles and wealthier merchants make use of these long distance signals as well, though the expense of long distance signalling is prohibitive for most commoners.