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

456 THE MORSE TELEGRAPH APPARATUSES.
Fig. 44 is another form of the sounder; the lever is adjusted
at the end by the spiral spring, seen in the figure. Some
operators prefer one mode of construction, and others choose a
different kind; some prefer a heavy sound, others can hear
more distinctly a lighter tone. The sense of hearing is not
the same with all operators, and it is but natural that there
should be a difference in choice as to the sounder.
Of all the mysterious agencies of the electric telegraph,
there is nothing else so marvellous as the receiving intelligence
by sound. T'he apparatus speaks a language, a telegraphic
language, as distinct in tone and articulation as belong to any