International Code of Signals (thing) by Jurph
n or fewer flags 1. The volume of available messages in even a small subset allows a carefully constructed code book to contain all but the most obscure messages. An extended history In 1738, Mahé de la Bourdonnais proposed to use ten colored flags to indicate the numbers from zero to nine. With three sets of such flags, all separately colored, 1,000 code combinations could be made. Ignace Chappe wrote in 1824 that he considered it a regrettable mistake that the system of de la Bourdonnais h...
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