Theory and practice of the electric telegraph; a manual for operators and students (1875)
Churchill, Charles Henry, d. 1904. [from old catalog] · Oberlin, Ohio, Sherman & bros. · leaf 100
ever L. The dot-ted lines show——the course of thewiresunderneaththe switchboard.Woods Button Repeater. The necessary batteries and instruments, except the usual local connections,are given in outline to assist the learner in understanding thearrangement. E and W are the east and west Main lines,… … 8 0 MANUAL OF TELEGRAPHY. 3. What arrangement will give two independent circuits? For two circuits close the button 4 and let the lever L standon number 1, as in the figure. 4. How is a through circuit pro luce I? For a through circuit open the button 4 which throws offthe ground connection between…
Telegraph
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