Historical sketch of the electric telegraph : including its rise and progress in the United States (1852)
Jones, Alexander, 1802-1863 · New York : G.P. Putnam · leaf 40
itli twolittle knobs, to perform the part of a hammer, rises betweenthese plates. When the armature is drawn to the magnet itstrikes one of them, and, on being drawn back it strikes theother. As they are of different tone, the re]3etition of thissignal at once draws attention to the register. This… … iui;?es Printing Telegraph. In Houses beautifully contrived jyi^iting telegraph—whichprints messages in Eoman letters—the electric current ismerely employed for signalizing, while the mechanical forceof magnetism and atmospheric pressure is used to imprint theletters on a revolving piece of paper.…
Telegraph
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
