The telegraph manual: a complete history and description of the semaphoric, electric and magnetic telegraphs of Europe, Asia, Africa, and America, ancient and modern.

THE MORSE TELEGRAPH APPARATUSES.
CHAPTER XXXII.
The Early Telegraph Instruments-Modern Lever Key-The Early Circuit
Changer-Modern Circuit Closers-Nottebohn's Circuit Changer-Binding
Connections-The Electro-Magnet of 1844-The Modern Relay Magnet —
The Receiving Register-The Sounder.
THE EARLY TELEGRAPH INSTRUMENTS.
THE present chapter will be devoted to the description of the
various parts of the Morse telegraph apparatuses, which have
been and are in use for practical telegraphy.
The original patented instruments were soon superseded by
mechanism more convenient for the peculiar service. On the
experimental line constructed between Baltimore and Washington, the register was similar to that represented by fig. 1,
having three pen points to indent the letter into the paper.
The perspective view shows the whole instrument. The
electro-magnet n H, the pen-lever L, and the armature F, will
be better seen on reference to fig. 3, which represents a part of
fig. 1. Numerals 1, 1, 1, of fig. 1, represents the reel of paper,
with its axle at Y, fitted into the brass standard u at 12; 2, 2,
is the paper coming from the reel, passing between the rollers
E F, as seen in fig. 2; 11 is a metallic trough; and 3 is the
paper after it has been marked by the pen points R; 4 is the
weight that puts in motion the clockwork revolving wheel B,
fig. 2, to which is fastened the pulley R', with an endless band
10, which puts in motion the wheel q. Fig. 3 represents the rear
part of fig. 1, showing the electro-magnet. The letters a b, in
figs. 1 and 3, are the line wires, one running to the battery,
and the other to the telegraph poles. When the current passes
through the coils, H I, the armature F is attracted, and the
lever w attached is elevated in the direction of the arrow,
causing the small steel points R to puncture the paper passing