[Electric engineering.] . he conduit. 15 ELECTRIC TRANSMISSION. 21 In these handholes a service box is placed. Fig. 24 showsone style of service box with its cover removed. A, £, and Care the main cablesthat run straightthrough the box with-out being cut. D, Eare the three-wire,branch-service cables,or tubes, for supplyingcurrent to the build-ings. These are at-tached to the maincables by means ofsuitable clamps, andafter the cover isbolted in position the FlG- 25- box is filled with insulating compound. Fig. 25 showsanother style of service box for use on the three-wire this four-wa
[Electric engineering.] . he conduit. 15 ELECTRIC TRANSMISSION. 21 In these handholes a service box is placed. Fig. 24 showsone style of service box with its cover removed. A, £, and Care the main cablesthat run straightthrough the box with-out being cut. D, Eare the three-wire,branch-service cables,or tubes, for supplyingcurrent to the build-ings. These are at-tached to the maincables by means ofsuitable clamps, andafter the cover isbolted in position the FlG- 25- box is filled with insulating compound. Fig. 25 showsanother style of service box for use on the three-wire this four-way box the main cables are fastened to ter-minals instead of passing straight through. Fig. 26 showsa handhole with its service box arranged for deliveringcurrent to overhead conductors. The main feeders, runningfrom manhole to manhole, are placed in the lower tiers ofconduits, and the service mains that run back from themanholes are run in the upper row, so that they will beaccessible for the connection of service 27. Joining Cables.—For low-pressure work, cablesare usually joined in the manholes by means of couplingboxes or junction boxes. Sometimes, however, joints mustbe made without the use of these boxes, in which casesthe job must be very carefully done. First, the soldered end of the cable is cut off and thecable carefully examined for moisture. If a little moisturebe present and there is still more than enough room for thejoint, it is allowable to cut off another short length. Ifindications of moisture are still present, heat should beapplied to the lead covering, starting from a distance and /. III.—9 22 ELECTRIC TRANSMISSION. 15 proceeding along the cable to the end. Thus the moistureis driven out at the cut. When the use of torches is notallowed on account of gas in the manholes, hot insulatingcompound, such as boiling paraffin, may be poured over thecable. This process is known as boiling out. To ascertainwhether moisture is present, the piece last cut
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