The Rathdrum tribune. (Rathdrum, Idaho) 1903-1963, 1915-05-21
OUR GREAT CANAL
How Vessels Cross From Ocean
to Ocean at Panama.
GOING THROUGH THE LOCKS.

Electric Locomotives Of Unique De-
sign, With a Cog Rail System, Are
Used For Towing Purposss--safs-
guarding the Lock Walls and Gates.
Forty electric locomotives of unique
design are used to tow shipping
through the huge locks Of the Panama
canal. When the canal was being
planned it was apparent that the vari-
GUS winch and capstan systems in
vogue for towing ships through exist
ing canals and locks would not do at
all for Panama. After a thorough
study of the entire problem of maneu-
vering ships through the locks at Pan
anna 1t was evident that they could not
safely proceed through the locks under
their own power and that substitute
for the ships power should embrace
the following requirements:
Ability to place the ship In proper re-
lation to the lock-
Capability for keeping the ship in its
course.
Accelerating and retarding the ship
without rupturing the lines.
The lines when once attached should
be used without change for lockage In
flight.
In passing through the canal from
the Atlantic to the Pacific vessel en-
tiers the approach channel in Limon
bay, which extends to Gatun, a dis
tance of about seven miles. At Gatun
1t enters series of three locks in
flight and is raised eighty-flpe feet to
the level of Gatun lake. It then
steams at full speed through the great
er part of the channel In this lake for
a distance of twenty four miles to Bias
Obispo, where 1t enters the Culebra
cut. 1t passes through this cut, which
has a length Of nine miles, and reach
es Pedro Miguel, where 1t enters
lock and is lowered thirty feet. Then
Ut passes through Mirafiores lake for
a distance of one and one-half milas
until 1t reaches Mirafiores, where it is
lowered fifty-five feet through two
locks to the sea level, after which 1t
passes out into the Pacific through an
eight and one-half mile channel.
The main features OF all the lock
sites are identical, and the following
brief description of the GaHun locks,
with special reference to the arrange
lment of the towing tracks, ship chan
nels, inciines and approaches, gives a
clearer conception of the towing
scheme In general.
There are two channels at Gatun,
one for traffic IN each direction. The
channels are separated by a center
wall, the total length of which is $3.50
feet There are two systems of tracks,
one for towing and the other for the
return of the electric locomotives when
returning idle. This, however, refers
only to the outer walls. For the CEN
ter wall therN is only one return track
IN common. for both the towing tracks.
The towing tracks are naturally placed
next ~ the channel side, and the sys-
tenn of towing utilizes normally not
le@s than four locomotives running
~ ong the lock walls. Two of them are
opposite each other in advance of the
vessel, and two run opposite each 9TH
er following the vessel. The number
of locomotives Ia, however, increased
when the tonnage of the ship de-
mands II.
Cables extend from the forward To-
locomotives and connect with the port
and starboard sides, respectively, Of
the vessel near the bow, and other ca
Ibles connect the rear locomotives with
the port and starboard quarters of the
vessel. The lengths OF the various ca
bles are adjusted by special winding
RI 11Vt fh1 80 xNia
vessel substantially In midchannel.
When the leading locomotives are start
ed they tow the vessel, while the trail
ing locomotives follow and keep the Ca
bles taut. BY changing the lengths of
the rear cables the vessel can be guild
ed, and to stop the vessa all the loco
motives are slowed down and stopped,
thus bringing the rear locomotives in
action to retard the ship. Therefore,
the vessel is always under complete
control quite independent of its own
power, which is not used, and the dam
ger of injury to the lock walls and
gates Is consequently very greatly les
Eened.
These towing tracks have a specially
designed rack rail extending the entire
Length OF the track between the rails.
1t is through this rack that the loco
motive exerts the traction necessary
for propelfing large ships and climbing
the steep inclines. When the locomo-
tive reaches one of the inclines between
the locks, the grade OF which may be
as much as a per cent, or when It is
rowing ship, the cog rail system is
utilized to enable the locomotive to
climb the grade and In the other case
to exert traction necessary for pulling
the ships. The cog or rack rail is laid
between the track rails and the loco
motive Is provided with a cog wheel or
rack pini0n to engage the rail.-Elec-
trio News.