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

DESCRIPTION OF THE APPARATUS. 201
passes out of the case, and is numbered 1, on the right hand.
So of the other wires, thus numbered. The dial has permanently marked upon it at proper distances and angles, twenty
of the letters of the alphabet, viz. A, B, D, E, F, G H, I, K, L, N,
N, 0, P, R, s, T, v,,. Y. On the margin of the lower half of
the dial are marked the numerals, 1, 2, 3, 4, 5,, 7, 8, 9 and
0. The letters, c, J, Q, u, x, z, are not represented on the dial,
unless some six of those already there are made to sustain two
characters each, of which the specification is silent. Each
needle has two motions; one to the right, and the other to the
left. For the designation of any of the letters, the deflection
of two needles are required, but for the numverals, one needle
only. The letter intended to be noted by the observer, is designated, in the operation of the telegraph, by the joint deflection of two needles, pointing by their convergence to the letter.
For example, the needles, 1 and 4, cut each other, by the
lines of their joint deflection, at the letter v, on the dial, which
is the letter intended to be observed at the receiving station.
In the same manner any other letter upon the dial may be selected for observation. Suppose the first needle to be vertical,
as the needles 2, 3, and 5, then needle 4 being only deflected,
points to the numeral 4, as the number designed.
I will now proceed to describe the arrangement of the springs
and buttons upon the platform, c c, figure 24 (representing a
Fig. 24.
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6'I 2 3 4- 5
i _i Li Li Li.. -- —'
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