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DELUNE & CO.'S SYSTEM OF LAYING UNDERGROUND CABLES.
In recent times considerable attention has been paid to the subject of
laying telegraph cables underground, and various methods have been
devised. In some cases the cables have been covered with an armor of
iron, and in others they have been inclosed in cast-iron pipes. For
telephonic service they are generally inclosed in leaden tubes. What
this external envelope shall be that is to protect the wires from
injury is a question of the highest importance, since not only the
subject of protection is concerned, but also that of cost. It is
therefore interesting to note the efforts that are being made in this
line of electric industry.
[Illustration: FIG. 1. Section of the Pipe Open.]
[Illustration: FIG. 2. Section of the Pipe Closed.]
Messrs. Delune & Co. have recently taken out a patent for an
arrangement consisting of pipes made of beton. The annexed cuts,
borrowed from _L'Electricite_, represent this new system.
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