Twentieth century manual of railway and commercial telegraphy (1905)
Meyer, Frederic Louis, b. 1875 · Chicago, New York, Rand, McNally & Company · leaf 31
examjile, by inserting plugs in the intersectionsC and K, and D and L, the instrument that belongsto the local section K, L is inserted in the line of C,D. It is customary to have a board wired in such amanner that the plugs are normally inserted in adiagonal line across the board, thus connecting… … Connections onlarge boards are insome instancesmade by inserting adouble plug in oneof the holes between a disc and a strap. ^^^-^O- Loop Peg and Cord. This plug is made in a similar manner to theplug used in a cut-out, Fig. 18, excepting it hasa round nose. A double plug for switch-board purposes…
Telegraph
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