File:Bell telephone magazine (1922) (14569609350).jpg

Identifier: belltelephonevol21mag00amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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cluded in theline in which all plows, tractors, andtrailers are connected from one endof the train to the other, either by one-inch steel cables or by direct-actingtowing hooks and eyes. The frontplow roots through the earth with a ^y^-inch. share, loosening and break-ing up the ground to a depth of from30 to 50 inches, thus insuring uninter-rupted passage of the following plow,which deposits two cables and thelightning shield wires, all properlyspaced, in the ground. This 100-tontrain, with its more than 400-horse-power pulling force, moves forwardat the rate of a brisk walk, laying thecables and lightning protection wiresas it goes. Pauses are necessary onlyto change cable and wire reels on thetrailers and to remove any major ob-structions encountered in the ground. Where the ground is not hard andis free of rocks, and thus there is nodanger of interruption to the plowfrom buried obstructions, the trainmake-up may omit the rooter plow,as in Figure 2. On the other hand, it frequently
Text Appearing After Image:
.\ ^;i Fig. 2. View from the RearOne tractor and the rooter plow are omitted in this train (cf. Fig. 1), since the rooting operationis unnecessary where the ground is free of obstructions Fig. 3, left: Where ground conditions are asbad as this, the rooter plow goes ahead, andthe cable-laying plow follows as a separateoperation. Fig. 4, below: Power appliedfrom the single-drum winch of a stationarytractor comes in handy for pulling the train,or any part of it, up hills or out of mud

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