The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1896-10-28

strung close together as we passed
them, and that was all.
Pretty soon we saw the disc of white
light which marked the north portal
of the tunnel, and the next moment we
were in broad daylight with a signal
200 feet off standing at danger. The
lever was dropped back to Us starting
point and the Kissing of the airbrakes
prepared US for a sudden, though not
violent stop. Then we gently switched
onto the south-bound track, and ran
back through the tunnel by gravity
alone. The engineer told me that we
had exceeded so miles an hour on our
outward journey, and 1 can quite be-
lieve him.
When we had reached the siding on
the south side of the tunnel, Mr.. Shep-
pard began to display the interior
works of the electric motor He took
off the front door of the wooden box
and showed two sets of strong copper
ribs, so curved and proportioned that
when the lever was pulled out one
notch the top copper rib on one side
overlapped and touched that on the
other. AS the lever was gradually
pulled farther out the succeeding pairs
Of copper ribs came into contact, one
pair after another until tho full cur
Itul ldSSEIl OuSlA tliC ~
series of copper discs, in another part
of the box. sent this current through
the motors in the proper direction to
make the engine go forward or back
ward.
I'VE should never have been able to
handle a current of 1,50O horse power, -
said Mr. Shepard, only for beautiful
invention conceived by Elihu Thomson.
The sparkling from switching on or off
such current would melt the copper
contacts were it not for a series of cleo
tro-magnets placed opposite the contact
points. When the current is switched
on or off a current is sent through
these magnets, and the magnetic field
blows out the sparks"
Mr.. Shepard showed how this was
done by switching on the current while
the door of the controller box was off.
There was binding flash of light for
an instant, blown out as soon as it APP
peared by the electromagnetic.
Viewed from the outside, the electric
locomotive looks like the tenders of two
yard switching engines coupled togeth-
er. The cab is large and roomy, and
contains in addition to the apparatus
already mentioned, an electric air
pump for charging the brake reservoir.
The compressed air whistle with which
the engine is filed is as loud and shrill
as that of any steam locomotive.
The eight wheels of the electric en-
CINE are each feet inches in diam
eter Each pair has its own motor, -of
$50 nominal horse power, but capable
Of developing the power considerably
in excess of that limit The motion of
each armature is delivered to the wheels
by five steel arms which fit in between
tfe smokes near the rim
The limit of the hauling power of
one Of these electric engines has not yet
been reached. owing to the weakness
OF the coupling which hold the train
together. The best hitherto recorded
performance has been the hauling of a
train of A loaded freight cars and
three engines, weighing altogether 1900
/ tons. While this train was on
the upgrade a pin came out
in one of the couplings. AS
son as this defect was repaired the
electric locomotive started the entire
train with stretched couplings and ac-
tolerated its speed until it reached -
miles an hour On another occacon
3S loaded freight cars and an attached
steam engine was hauled through the
upgrade at speed of 20 miles an
hour. Trains of 500 tons in weight have
been taken through the tunnel on the
upgrade at 40 miles an hour
The electric engines not only haul
trains. but give the weight of them 1t
has been found by experiment that it
requires IA ampere of current to drive
the engine by itself 1t has also been
found that each ampere of current ex-
erts drawbar pull of ESQ pounds. So
that by taking the number of amperes
recorded on the guage, substracting IA