Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1899-03-05
BLOCK SIGNALS EXPLAINED.
Method of OBTAINING Trains for
safety.
New York SUM

The entire New York Division Of the
Pennsylvania railroad, which extends
from Jersey city to Philadelphia. is pro-
tected by block signals. but of three diff
ferent designs. When. two years ago,
tho company began 10 supplant the sys-
tenn operated by manual power with an
automatic device. the improved system
was hrst put in al the Jersey City end
Of the division. Work was started subse-
quently at the other end, until the line
was equipped as far east as Monmouth
Junction. while the same system was in
stalled on the section between Jersey City
and Perth Amboy Junction. Along the
twenty miles between Monmouth and
Perth Amboy functions signals Of the old
style are still in use.
The new automatic signals are worked
by a combination Of electric and pneu-
matte power. The rail joints are con-
nected by wire. so that there IS a con-
tinuous circuit Of electricity, supplied by
batteries stored In pits along the line. A
few feet from the base of each signal
pole Is an attachment known as a circuit
breaker. The passing of a train over
this circuit breaker m"anipulates a valve
half way up the pole. The valve is at the
outlet OF a small air cylinder. which is
filed automatically from a reservoir un-
der the base Of the pole. The release of
this valve causes a rush Of air. which
forces the two signal arms up so that
they rest at right angles with the upright.
The two signal arms are what are known
az home and distant signals. the
top one, a red blade. denoting that the
home" or present block is cleared. The
lower arm. Il similar green one, indicates
the condition Of the next block beyond.
At the ends near the poles red and
green disks are held IN metal -semaphores.
Lanterns are suspended behind the disks
when the blades are thrown up, and red oil
green lights are displayed. When the
blades are lowered the white lights OF the
lantern show. When the train clears the
| block the passing Of 10 over the next cir
cuit-breaker completes the last cir
cult. the action Of which Is 10 empty aie
close the air chamber on the last signal
pole and drop the upper or nome bIaoe'
The opening Of the next circuit l. accom-
| plished at the same time n Doth arm'
are raised.
There is also a connection so arranged
that when the circuit-breaker at the Sc
cond pol4 beyond is compressed, the dis
tant signal two blocks behind, is low
cred. showing with the lowered red blade
that the track is clear for two blocks IRON
thar point. At junction points the auto
matic device is used in connection will
band-levers i'm towers. The electro-pneu'
matic device sufices 70 throw the signal
blade 10 the angle denoting danger OF
| an obstructed track. But on account o.
the operation Of switches the blades are
lowered by ha~nd-poWer. Inc track ma
be cleared for blocks ahead' Dut II 3
switch is set for a branch the signal fol
the main line is held at danger while the
operator drops the branch-line signal an'
vice versa. -,
ON the Delaware. Lackawanna anC
u,oetorn railroad the Hall system O.
block signals is used. II Is 50 operate
tbst a red signal ball is nominally at dan
Ger II is worked entirely by electriclty
The signal at the besinnlng o! d hIock
80 me next train approaches, n no
merely when the first train has lett th'
hfogK-