His first process is by means of the electric current to sound a little
bell, which simultaneously alarms all the stations on his line; and
although the attention of the sentinel at each is thus attracted, yet it
almost instantly evaporates from all excepting from that to the name of
which he causes the electric needle to point, by which signal the clerk
at that station instantly knows that the forthcoming question is
addressed to _him_; and accordingly, by a corresponding signal, he
announces to the London boy that he is ready to receive it. By means of
a brass handle fixed to the dial, which the boy grasps in each hand, he
now begins rapidly to spell off his information by certain twists of his
wrists, each of which imparts to the needles on his dial, as well as to
those on the dial of his distant correspondent, a convulsive movement
designating the particular letter of the telegraphic alphabet required.
By this arrangement he is enabled to transmit an ordinary-sized word in
three seconds, or about twenty per minute. In the case of any accident
to the wire of one of his needles, he can, by a different alphabet,
transmit his message by a series of movements of the single needle, at
the reduced rate of about eight or nine words per minute.
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