Modern practice of the electric telegraph. A handbook for electricians and operators (1872)
Pope, Frank L. (Franklin Leonard), 1840-1895 · New York : D. Van Nostrand · leaf 41
FIG. 12. 56. THE RELAY MAGNET.—The construction of therelay is shown in fig. 12. M is the electro-magnet, … •THE MORSE, OR AMERICAN TELEGRAPHIC SYSTEM. £[. which is placed in a horizontal position, and is movableby means of the screw a. The coils of the magnet areof fine wire, usually from No. 30 to No. 36 in size, ofgreat length and closely wound.* The ends are con-nected to the line circuit by the…
Telegraph
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