Schilling telegraph

The Schilling telegraph is a needle telegraph invented by Pavel Schilling in the nineteenth century. It consists of a bank of needle instruments (six as developed for use in Russia) which between them display a binary code representing a letter or numeral. Signals were sent from a piano-like keyboard, and an additional circuit was provided for calling attention at the receiving end by setting off an alarm. The code was read from the position of paper discs suspended on threads. These had different colours on the two sides. Each disc was turned by electromagnetic action on a magnetised needle. rdf:langString