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

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
Fig. 31, lejt: Oil is sprayed onthe cable as it enters the plow,to reduce friction. About fourgallons of oil per mile is appliedby the spray gun seen at the rightof the lower cable. Fig. 32, below:This shows the coupling betweentractor and plow, released. Whenthe shear pin—with a breakingpoint of 72,000 pounds—snaps,the heavy tubular guides hold thetongue in place so that recouplingmay be quickly done
Text Appearing After Image:
Fig. 33. Back-fillingis part of the cable-laying operation. Adevice under the reartrailer mounds up theearth over the furrow,and a tractor runs overit when bringing up anew reel of cable Plowing Cables into the Ground 105 24 and thence through special ductsin the share to the desired locationsin the ground. This operation takesplace, of course, simultaneously withthe cable plowing. Changing the reels is necessary forevery cable length, usually at 1500-to 3000-foot intervals. Where onlyone cable is being laid, this is a simplematter; but where two reels are in-volved, the changing of the front onepresents some difficulties, as can bevisualized by referring to Figure 2,The rear trailer completely blocks theoperation. In order to leave space between thetwo trailers, thus permitting the frontone to be loaded, the rear trailer isdropped from the train as it movesalong, about 50 feet before the cable-end leaves the rear reel. This is ac-complished by releasing the relaywinch, thus disconnec

Note About Images