The telegraph manual: a complete history and description of the semaphoric, electric and magnetic telegraphs of Europe, Asia, Africa, and America, ancient and modern.

SUBTERRANEAN LINES IN GREAT BRITAIN. 589
in 18S7, I witnessed the laying of some subterranean wires
along the Champs Elysees. Trenches were dug about four feet
deep and about three feet wide. At the bottom a small trench
about twelve inches wide and ten inches deep was dug, for the
wires to be placed. There were about thirty wires drawn
taut, some two inches apart, along and in this smaller trench,
sustained by boards temporarily, and until the'trench was
filled with asphalt and very dry gravel, as adopted in Hindostan, and hereinafter explained. This gave a solid mass of
composition around the wires. I have been informed that the
wires proved to be perfectly insulated. They were covered
with cotton and shellac. The process was expensive, and it
yet remains an experiment.
SUBTERRANEAN LINES IN GREAT BRITAIN.
In Great Britain a very large number of lines have been laid
underground, the greatest extent of which has been by the
Magnetic Telegraph Company. These subterranean lines extend over England, Scotland and Ireland, and they work
with an efficiency and durability fully commonsn:afto witl
the expectations of the company
Fig. 1.
Upon the lines of this company magneto-electricity, described elsewhere in this work, is employed. Some telegraphers
are of the opinion that this species of electricity is more serviceable on underground lines than that which is generated by the
ordinary chemical voltaic batteries.
In a communication from the now Sir Charles T. Bright,