The daily sentinel., 1909-02-03
THE BLOCK SYSTEM is
GREAT LIFE PROTECTOR

+ Rather an unique advertise +
+ ment has been adopted by the +
I. Union Pacific railroad, which +
+ consists of a miniature block +
+ signal, installed in the window +
r of their city ticket office, Seven +
+ teenth and Curtis streets, which i.
+ is an exact reproduction of the +
+ automatic block signals used !!
+ along its line, says the Denver +
I. News. +
+ I. I. + + + + J. + + 4. +
The mechanism is enclosed in
glass case. which provides for the
working of the signal to be seen from
either inside or outside of the office.
The signal is worked with a storage
battery. identically the same as when
in actual use, governing the move
ment of trains. When the arm is ex-
tended horizontally, or in addition
red lights are displayed, it indicates
danger-"stop." When the arm is
degrees, or in addition a green light
is displayed, it indicates safety
proceed.
The mechanism, an electrical ap-
pliance used by the Union Pacific in
the working of it's automatic block
signals, consists of the bonding of
defnding track limits so as to make
electrical current accessible to all
parts. A motor is installed at the base
of each semaphore. as seen along the
lines of the Union Pacific. a storage
battery also being provided with each
semaphore. When the track circuits
and relays are all in normal working
condition, the motor in the base of
the semaphore pulls the semaphore
arm down to an angle of 60 degrees,
which, under the rule. indicates
safety" and proceed" An electri-
cal working clutch used in connection
with the motorholds the semaphore
arm in this position only under safe
conditions. An engine or car occu
pying the main line short circuits the
track, throwing the electrical clutch
off, the semaphore arm going to a
horizontal position. with mast of
gravity indicating stop" The bond
ed districts governed by any one sig
nal are limited to from one and one
half to two and one-half miles. Sew
eral signals are. of course. maintain
ed in one district. An open switch,
or, In fact. any obstruction, has the
same effect on the working of the
signal as when the main line is oc-
supied by a train. AS an additional
safeguard, when a track is protected
by automatic block signals, a broken
rail breaks the current ana throws
all signals Immediately at stop" the
signals being so arranged that it
would be a physical impossibility for
train to approach such broken rail
without warning
Mr.. r. S. Ruble, city passenger
agent for the Union Pacific, tells an
Interesting story of a trip made from
Denver to Ogden in company with a
large number of stockmen en- route to
the stock convention at Los Angeles.
They were aboard the Union Pacific
LOS Angeles Limited" and while
passing through Echo canon at a
speed of sixty-five miles an hour the
air brakes were felt to apply, the
train gradually slowing down, SINH
lar to making an ordinary station
stop. The party, noticing that they
were between stations, became inter-
ested in the cause leading up to the
flyer coming to a standstill. In step
ping to the ground they noticed that
the automatic block semaphore arm
stood at stop" The actions of the
train and engine crew were observed,
and it soon developed that broken
rail had been discovered. which in it.
self shows the effectiveness of the
block signals, as well as their safety
| to the travelling public at large.