Evening star., 1911-05-27

effectively to stop any vessel up to TO-
OO0 tons in size moving at as much as
| three knots an hour.
| NO vessel will be permitted to enter the
| locks under its own power. Ships will ap-
proach hugh central guide walls. which
they will be met by four electric towing
| locomotives running on narrow gauge
tracks. Two of these will hitch to cables
at the bow and will pull the ship into the
locks. The other two will hitch to cables
/ al the stern and hold the vessel back,
Keep 1t from moving too fast and stop II
when the gates are cleared AS nearly
every accident in lock operation in the
past has arisen from vessels passing
| through under their own power, the elec-
trio towing locomotiv practically in
| sure absolute safety
But. with that characteristic determine
ton to eliminate every possible chance of
accident, Chief Engineer GoetheIs has
| gone even farther. There will be two
sets OF gates at every vital point in the
lock system. 80 that If. by any remote
chance, vessel should ram down one
set there still would be another to pro-
tect the lock. These double gates at vital
points move in unison, 30 that there are
| always two effective safeguards. Should
vessel break away from the towing ap-
paratus or otherwise become uncontrolled,
| 1t might, one time in many thousands,
succeed in battering down one gate.
Should 1t do so there is still not a. chance
| in million that it would ram down the
second one.
y X
But suppose It did-the canal locks will
be prepared for 1t. A large cantiIever
bridge will be
Locks Prepared to mounted on . pivot
Protect Ships. ~., Dsss on .. tas Inc middle middle
q Tn
thing went wrong and tho water should
begin rushing through the locks at
destructive speed OF about twenty-eight
feet second. this bridge would be turned
across the lock and a set Of wicket grid
ers. made OF the hardest nickel steel.
would be let down. one end fast to the
bridge and the other end engaging an
Offset In the lock floor. Each Of these
gfrders would make a sort Of perpendicu-
lar railway. on which hugh sheets OF
steel, mounted on ball bearing rollers.
would be let down to check the current.
When all the wicket girders and all the
sheets OF steel are in position they will
make a steel dam which will effectively
restrain the flood. There IL such an emer-
gency dam at the Sault Ste. Marie canal.
ana although 1t had grown rusty by dis
use. 1t was most effective when an acci-
dent occurred there some time since.
The gates by which the water level IN
the locks will be regulated are ponderous
anairs. their weight varying from 400 to
ooO tons. Each gate Is composed of two
leaves. hinged to the side walls of the
locks like an ordinary pair Of one-way
double doors. except that they do not
shut straight across the channel. hnt
come together like a hattened y. with
the apex pointing upstream Forty-six
gates of two leaves each will be re-
quired in the lock system, They will be
opened and closed by a huge arm weigh
ing 10000 pounds and having q diam
eter of sixteen inches
The work OF building the six locks re-
auired for the canal is proceeding with
unexampled dispatch. It requires over
two million barrels Of cement and as
many cubic yards of stone and of sand
to build the locks at Gatun. Practically
the same amount will be required for the
Pacific locks. The work at Gatun was
twenty months old May !, and the locks
are approximately two-thirds Completed
Those on the Pacific side are also going
forward at surprising speed. The sand
for the concrete Is taken from islands in
the Atlantic and the Pacific by dredging.
and the rock from Porto Bello and An
con. The Porto Bello plant can crush
six thousand two-horse loads Of rock a
DAY. The concreting materials for Gatun
are brought to that point through the
canal on barges under tow.
The concrete handling plant at Gafuu
is the largest OF it's kind in the world
Huge clam shell