. Operation of trains and station work and telegraphy . and the perpendicular bars have no connection,space enough is allowed for a sheet of writing paper toplay freely between them. GROUND WIRE. Every office is supplied with a ground wire whichconsists of a wire attached to a rod driven several feetin the ground, or to a gas or water pipe, the two latterbeing preferable. The rod of iron should be filed orscraped bright and clean for several inches, and insulatedcopper wire spliced to five or six feet of bare copperwire wrapped evenly around the brightened part of therod, then tightly secured
. Operation of trains and station work and telegraphy . and the perpendicular bars have no connection,space enough is allowed for a sheet of writing paper toplay freely between them. GROUND WIRE. Every office is supplied with a ground wire whichconsists of a wire attached to a rod driven several feetin the ground, or to a gas or water pipe, the two latterbeing preferable. The rod of iron should be filed orscraped bright and clean for several inches, and insulatedcopper wire spliced to five or six feet of bare copperwire wrapped evenly around the brightened part of therod, then tightly secured and soldered. Only theterminal ground wires are in use upon a line; their useat the intermediate offices is only for testing purposesand in case of interruption of the line to notify thetesting operator and receive his instructions. The in-termediate stations upon inserting a ground wire divideit into two independent circuits; there must be a mainline battery at each terminus in order that the two cir-cuits may work on either side of it. 34 TELEGRAPHY. SWITCH BOARD CONNECTIONS. Ground- * Inst. No. 1 ^ -© Inst. No. 2 < 1 ( 1 < <N • < < ., 1 ) ^ -•^ No. I cut out with inst. 2 cut out at the 36 TELEGRAPHY Orouod- ^ Inst. No. 1 ^ iDSt. No. 2 ^ * ^ » -< *-< (N C o 6 6 ..........i 1 i ) ...J Inst. No. I on No. i W. to No. 2 on No. i E. and No. 2 W Ground. Inst. No. 1 ■£ Inst. No. 2 ^ w ^ m -< -^ .. 1 c i J Inst. No. I on No. i E. to No. 2 W., Ground on No. i No. 2 on No. 2 E. to Ground. TELEGRAPHY 37 Ground- ^ Inst. No. 1 ^ lust. No. 2 ( > ( ) o < 4 • >..... No. I W. to No. 2 E., No. I E. to No. 2 on both circuits. Oround. =£ Inst. No. I Inst. No. 2 c 2 09 aw > O 4 > i \ 1 i c __ I— o o Spare O.
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroa, bookyear1919
