Year: 1876

The Highland Railway of Scotland
has introduced upon its road what the
English journals describe as novel and
ingenious combined block and signal
system, the invention of DIR. Whyte,
who has devoted several years to the
work Of improving the mechanical ar
rangements for operating railway trains.
The system is entirely self-acting, and
its operations are performed with the
agency of an electromagnetic machine
of simple contraction. An engine rum
ming past, say two stations, blocks the
line at the first by raising semaphOre /;
places an automatic check against the
passing of a second engine by the ring
ing of an alarm bell on the second en-
gine itself. should it attempt to follow I;
announces its approach to. the second
station. or can be stopped bv the station
master there; while on reaching that
station, it clears the line at the previous
one of both semaphore and alarm bell,
so as to leave it free for any approach
ing train. The apparatus itself may be
divided into two parts, one being on the
engine and the other connected with the
line. Four wire brushes, each pair me-
tallically connected, are suspended from
the engine, one pair having a battery
and bell i'm circuit, and the other a bell.
A wheel descends alongside these brush
es. On the line, between the rails, at
such distances as may be thought re-
quisite, or in close proximity to each
station, series of insulated metallic
plates, in an air-tight box, are laid
down, each plate being from five to ten
feet long. By the side of each pair of
plates. the ends of which are connected
by wires, is placed an electromagnetic,
with wires from a battery attached. The
keeper of the magnet is fixed to lever
by means of a pully, and rs the engine
travels past. this lever is pressed upon
by the wheel above mentioned, and the
keeper is forced up against the poles of
the magnet. Thus the semaphOre arm
is raised and the line etlectually block
ed. With the view, however, to guard
against a possible inattention on the
part of the driver of an engine approach
ing the apparatus, the box is left in
such position that should his engine
pass over it while the signal is up the
alarm bell on the engine itself is in
stantly rung. The first engine having
successfully blocked the line i'm the rear,
proceeds to the next station or signal
post, where the line is again blocked !;
and by means of wires to the last box
and mechanism similar to that above
described, the electromagnetic at the
former station is released, the semaphOre
lowered, and the way left clear between
these two sections. Thus it is clear
that each train protects its rear for the
distance between each pair of plates.
The line being, as it were, divided into
sections, each train as il enters a section
instantly blocks it so that no other train
can follow until the first has proceeded,
without the bell being rung as WARM
ing. Connected with this automatic
electrical block system is an arrange
ment by which each train can announce
its approach to any station, and another
for giving the statiOn-master the power
to stop a train by causing the bell on
the engine to ring. The brushes on the
engine are the means by which this is
accomplished; powerful battery placed
at one station, or smaller batteries placed
i'm suitable positions along the line,
being the agency by which the appara


tus is operated. As these batteries are
never in circuit except when train
works them, the waste is reduced to a
minimum. The advantages claimed for
this system are that, being self-acting,
it entirely dispenses with manual labor,
which az some critical moment is apt to
be at fault; that its certainty of instan-
taneous action is secured by the con-
cealment of its working parts, and their
protection from vet and dust, and
finally that the expense of application
is comparatively small.