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The rise of market sensitive information

Extract from Telegraph Code Book

Code books for business (1905) : coding to cut cost

Commercial codes became available 'off the shelf' in the 19th century. Books could be bought, arranged like dictionaries, listing useful phrases or sentences, each with a corresponding code word. The idea was to use these codes to cut the costs of sending a telegram.

Many codebooks were published, most using actual dictionary words as their codes. For example, in the early ABC Code, the word 'Pascoela' was to mean 'Natives have plundered everything from the wreck'.

Later, books began appearing with artificial code words in the form of five letter or number groups, to cover even more phrases and words. Thus, in the 1905 edition of the ABC Code, those natives plundering the wreck were denoted by the group 'ewvgl'.

Using books like these had another benefit, though. Messages were meaningless to anyone who didn't have a copy of the code readily to hand.

Portable two-needle telegraph - a Connected Earth artefact, now in the Science Museum Collection

Portable two needle telegraph (1850s) : finding fault with the system

No telegraph system was perfect, and all networks suffered faults every now and then. The question was how to find where the fault was and what had caused it.

This portable two-needle telegraph was the engineer's greatest weapon in fault-finding. In the same way that a telephone engineer plugs in a portable telephone to test telephone circuits and systems today, the Victorian telegraph repairman would wire this telegraph into the line to find the problem.

It was a handy device, which doubled as a two needle telegraph and a test meter. It's a beautifully made piece with precision engineering on the inside and a range of extra numbers and letters on the front, so that it could be used to measure more than one scale.

fun and games

Can you beat our games? Explode equipment to see what's inside, hear the changing sounds of telecommunications, see how telecommunications designs have changed over time or send an e-postacard.

what's on

The UK's first permanent gallery dedicated to the history of information and communication technologies opens in the new Information Age gallery at London’s Science Museum.

audio history

Take a trip down memory lane with extracts of the interviews which have been recorded as part of the Connected Earth oral history programme.

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