Centre Democrat. [volume] (Bellefonte, Pa.) 1848-1989, 1883-06-28
Electric Wire TramWay.

hurgh, To a system which he has devised
for transporting vehicles, containing
goods and passengers, to "a distance by
the electric current, independently OF
any control exercised from the vehicles
themselves. Prof Jenkins idea Is To
employ strained metal cables, which
will serve both to sustain the load and
convey the electric current. The
frames or trucks supporting the load
run along the cable on wheels, and the
cars or loads are suspended below
them from the axlcs Of the wheels. In
the simplest arrangement Of the line
there is break of continuity at each
post supporting it; and the sections OF
cable are themselves insulated from
each other and the earth. They are
however, capable of being connected
by movable coupling-pieces, actuated
by the train, so that all the sections re-
ceiye the exciting current and form
part of the general circuit. The cur.
rent is supplied to the line by station
AIRY dynamo-electric machine driven hy
a steam engine or other motor; and
since the line is elevated from the
ground on insulating standards, the
same dynamo will supply considerar
bic length of line, rs the leakage need
not be excessive if proper precautions
are taken. With ground lines Of cleo
trio railroad, like that of Siemens or
Edison, the leakage is very marked,
and Mr. Edison LAS adopted the plan
OF dividing the whole line into short
sections of few miles, with stations
and feeding dynamos at each. Driver
ncr >icmcns fayors the use OF an insu.
lated conductor supported beside the
line. and giving current to the motor
on the train by means Of running
connection pulled by the train. Profs,
Ayrton and Perry have. rs is well
known, sought TO overcome the leak
age difficulty by making the line in
short sections, each Of which is put in
circuit with the dynamo in turn as the
train progresses, by an automatic &C
tion Of the train itself In this way,
there is only one section electrified at
time, namely, that over which the
train is running and the leakage on
the whole line is consequently very
small.
The loads or cars on the telphcrage
line are connected together in trains,
and the length Of train is nearly the
length Of a section Of the cable con-
ductor. On passing either Of the NOV
able coupling pieces between two sec
tions. the train throws Il out Of action,
disconnecting the two sections at that
point; but circuit between these
sections Is maintained through the
wheels OF the train itself and con-
ductor on the train. In circuit with
this conductor is dynamo-electric
motor, which is actuated by the cur
rent. and propels the train by driving
the wheels. The power provided is
more than sufficient TO keep up n max.
imum speed. and the train is provided
with governor which, when the speed
it sufficient. closes shunt and allows
the current to pass without trayersing
the coils of the electro-motor. The
governor acts directly to check the
train If the speed becomes excessive,
by short-circuiting the eleCtro-mOtor,
or otherwise bringing electric brakes
into operation. To further insure that
one train shall not oyeTtake another,
Prof Jenkin provides an automatic
telegraphic communication along the
line, and the trains in passing close
and open the telcgraphic circuits, This
automatic telegraph actuates circuit
AAN0FAH btN "tth AtAF AAlAfANAih SfAtAhlAo
Of the main cable or conductor so as TO
maintain connection between the sec
tions for a certain distance behind the
train quite Independently, it may be,
Of the movable coupling pieces 1t is
obvious that a following train entering
upon part Of the line in which the
sections are thus connected will have
its speed checked. as the application Of
the power upon the train depends upon
there being break in the electrical
coupling between the two sections on
which the train is for the moment
supported.