Spirit of the age. [volume] (Woodstock, Vt.) 1845-1913, 1883-05-23
Electric Wire Tramway.

:" Electric Wire Tramway.
"Telpherage' is the name given by
Fleming Jenkin, the wcll-known
electrician and professor of civil engi.
neering in the University of Edin-
burgh, to a system which he has devised
for transporting vehicles, containing
goods and passengers, to 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 aXles 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, actuatcl
by the train, so that all the sections re-
ccive 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 a consdera-
bic length of line is the leakage need
not be excessive if proper precautions
are taken. With ground lines of cleo
trio railroad, like that of SicmcnS or
Edison, the leakage is very marked,
and Mr.. Edison has adopted the plan
of dividing the whole line into short
sections of Il few miles, with stations
and feeding dynamos at each. Driver
ner Siemcns favors the use Of an insu-
lated conductor supported beside the
line, and giving current to the motor
on the train by means Of a running
connection pulled by the train. ProfS'
Ayrton and Perry have, as is we'll
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 ac-
ton of the train itself. In this way,
there is only one section electrified at Il
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 tclphcrage
line are connected together in trains,
and the length of Il train is nearly the
length Of sec ton Of the cable a con-
ductor. On passing either of the mov-
able coupling pieces between two Sec
tions, the tram throws it out of action,
disconnccting the two sections at that
point; but the circuit between these
sections is maintained through the
wheels of the train itself and Il con-
ductor on the train. In circ"it with
this conductor is dynamo-clCctric
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 Il max
imum speed, and the train is provided
with a governor which, when the speed
it sufficient, closes shunt and allows
the current to pass without traversing
the coils of the clectro-motor. The
governor acts directly to check the
train if the speed becomes excessive,
by short-circuiling the clcctrO-motor,
or otherwise bringing electric brakes
into operation. 10 further insure that
| t,,i,, ,hn1 n,-art Dlyn nnnt h1r,
Prof, Jcnkin provides an automatic
Geographic communication along the
line, and the trains in passing close
and open the Geographic circuits. This
automatic telegraph actuates circuit
closers between the different sections
of the main cable or conductor so as to
maintain connection between the Sec
tions for certain distance behind the
train quite independently, it may be-
of the movable coupling pieces. 1t is
obvious that 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 a break in the electrical
coupling between the two sections or
which the train is for the moment
supported.
The XuluS'.