1. acoustic telegraphy The system of sound-reading in telegraphy, universally used in the Morsesystem. The direct stroke of the armature of the electro-magnet and its "back stroke" disclose to the ear the long and short strokes, dots and lines, and long and short spaces as produced by the dispatcher of the message. In the Morsesystem a specialmagnet and armature is used to produce the sound called the "sounder;" in other systems, e. g., Steinheil's and Bright's apparatus, bells are used. (See Alphabets, Telegraphic.)
Definitions of acoustic telegraphy
