Modern practice of the electric telegraph : a handbook for electricians and operators (1874)
Pope, Frank L., 1840-1895 · New York : D. Van Nostrand · leaf 43
Fig. 13. This is provided with a key, as shown in the figure, thewhole being conveniently and compactly arranged to fitinto an oval case four or five inches long, which may becarried in the pocket. It is an extremely convenientapparatus for line repairers. The cut shows the ar-rangement… … ~tUTTL£-#+K Fig. 14. 57. The Sounder.—In many of the larger telegraphoffices the recording apparatus is dispensed with, andthe communications read by the sound of the armaturelever. In that case the Sounder (fig. 14) is employed inthe place of the register, the connections of the wiresbeing…
Telegraph
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