The life of George Stephenson, railway engineer - Lighthouse ...

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RAILWAY SYSTEM AND ITS RESULTS.
effects a very material saving in the expensive element of rolling
stock. The oiEcers of a Company are enabled, the first thing every
morning, to consider the wants and requirements of the day. They
find that on one portion of their line there is likely to be extra trafBc,
whilst at some other station, during the previous day, or night, there
has been an accumulation of passenger carriages or vans. By the use
of the electric telegraph, nothing is so easy as to supply the wants of
one station from the surplus stock at the other, whilst the probabili-
ties are, that without the facility afforded by the telegraph, the stock
at one place would have been lying idle, although it was urgently
needed at another. Probably most lines would require fully 20 per
cent, more carriage stock than they now possess, if it were not for the
telegraph.
Whilst the value of the electric telegraph is very little understood,
the means of working it are, probably, still less properly comprehended.
It is generally supposed, that by some action of a handle at one station,
the electric current is sent through a wire to another. But the fact is,
that the success which the telegraph has obtained has been owing to
the adoption of an opposite principle. Signals are now made, not by
sending a current through a wire, but by the interception of the cur-
rent which is continuously maintained ; and this application is espe-
ciallj' valuable, not only on account of the increased facility, but also
on account of the increased security afforded. To signal, without a
current through the wire, requires a machine in the hands of a skilled
person ; but to signal with a constant current through the wire, only
requires that the wire should be broken, which can be accomplished on
any spot by the most uninformed. The most unskilful, therefore, in
case of accident, are fully able to use the electric telegraph, so as to
give notice of difficulty, or danger, and so as to receive immediate aid
and assistance from the nearest stations, in both directions. Nor can
there be any doubt, in such case, as to the indications of the telegraph.
Alarm, misinterpretation, or other causes, might prevent a message
from travelling, or being read correctly, if it were dependent upon the
use of a machine and the skill of both the sender and the interpreter i
but where nothing more is needed than to intercept the flow of the
current, by the rudest method, there can be no doubt either as to the
operation, or as to its effect. Of course this cutting of the wire applies
solely to that which is called the " train wire," so that the messages of
the public are in no way interrupted.
Kecent projects gave promise of another, and not an unimportant
improvement in the telegraph. Great, it might be supposed, would be
the confusion, if two opposite currents of electricity met in one wire ;