St. Paul daily globe. [volume] (Saint Paul, Minn.) 1884-1896, 1895-03-18

veloped until it is pronounced by the
most eminent and experienced expert
engineers to be scientifically and me-
chanically perfect. 1t is remarkable
that such great engineers and orig
1nal thinkers as Eads, Keefer, Clark,
Morrow, LindenthaI and Eiffel. who
were planning ship canals, ship lifts
and ship railways, should have over
looked the pneumatic lock, more
especially in view of the fact that
Col. Haskell had already applied the
principle to the pneumatic dry dock,
which was in use all over the world.
and that merely to make the pneu-
matte dry dock into a wet dock, by
building up the side walls and putting
in end gates between them, would put
navigation hydraulics on an entirely
new basis and solve many ~.of it's
knottiest problems. -
Fortunately flor the rising gem
GRAFTON their elders have limitations
to their activities.
THE CONTINUANCE DESCRIBED.
''The pneumatic balance lock is pri-
marily steel caisson, of tank struc-
ture, working up and down in a water
We'll or pit formed in the, lower level of
the canal. Compressed air is the mo-
tive agent. In all the proposed works
the pits will be sunk in rock. The cost
will therefore be a minimum, and there
is no element of uncertainty
''The tanks, or caissons, will be bal
anced in pairs, each caisson having an
upper gated lock chamber adapted to
retain the vessel to be locked and water
to the stated depth (say twenty-seven
faat0 q
chamber, containing compressed air,
which is retained by a water seal
formed by the immersion of the lower
walls of the air chamber in the water
Of the pit, as in gas holders.
The compressed air is at such a
pressure that its lifting effort is very
mach greater than the downward eff
fort of the loaded lock-, and therefore,
when a lock is down, there is always
an elastic cushion beneath it's floor;
and when it is elevated to its highest
position the compressed air tends to
expand and raise the lock still. higher;
and should any accident occur the lock
cannot possibly fall but will on the
contrary rise and remain supported,
with perfect safety to itself and con-
tents, until the damage. is repaired.
ITO stop and hold the locks at the
proper height, to keep them level and
to soperate' them with Certainty. facIl-
fty and security, they are equipped with
a hydraulic auxiliary apparatus which
levels, actuates and controls them dur
ing manipulation and absorbs the I'M
equal forces due to wind and wave
action.
The air chamber in one lock is
connected with its fellow by an air con-
duit controlled by valve. In these
locks the air conduits will be twenty
one feet in diameter; and the valve is
so designed that it has no friction or
wearing parts, and it can be opened or
closed in one minute without shock
1.-THE air charge is kept at uni
form working pressure above the at
mosphere by a small, weighted equal
izing tank, which automatically takes
care of the changes in the volume due
To char ges in the temperature and
density Of the adjacent atmosphere
The working pressure in a lock 26 to %
feet draught is 14A pounds to the
square inch.
GATES MADE OF STEEL.
1.-THE type of gate proposed to be
used is a modification of the familiar
pontoon gate used in dry docks. 1t
is built of steel, very simple in con-
struction, and is operated by a pin
ion and wheel, as drawbridges are
operated. All the gates are dupli-
Gates, and while so simple and strong
as to be practically safe from dam
age, an injured gate can be removed
and replaced in a very few minutes.
''The principle on which the locks
operate is the familiar one of weigh
ing in scale, the locks representing
the scale pans and the compressed
air replacing the scale beam. The mo-
ton is due to a small difference in the
total weights of the water in the two
locks, just as the motion of scale is
caused by similar difference be-
tween the weight and the object
weighed. The locks move oppositely
and spontaneously, like scale pans,
one ascending while the other is de-
scending. The depressed lock con-
tains the normal depth GIG feet of
water, and floats like a pontoon, it's
air connection being closed and it's
hydraulic system by-passed, to that
end.
1.-THE elevated lock is firmly thrust
and held up against it's stops by the
compressed air, and is connected with
the equalizing tank to keep the air
pressure constant. 1t contains a sur
charge of water-that is to say, the
water in it is 271a feet deep, ~ feet
deeper than in the depressed lock.
and it is correspondingly heavier.
If, now, the lock gates be closed to
retain the water in the locks during
the transit, and if the operating valves
be manipulated, the heavier, elevat-
ed, lock will descend, and in the de-
scending will force the compressed
air into the air chamber of the de-
pressed lock and elevate it, reversing
| their relative positions.
THE PROPOSED ROUTE.
$50 much for the system. Now for
the route. 1t is the simplest and cas-
Isiest available. It is proposed to wild
rem deepen and straighten the Well
and canal from Lake Erie to a point
just south of the existing locks, which
Will be undisturbed, and thence turn
toward the Niagara river and make
long level to be called the Niagara
section, reaching to the Niagara
gorge, the descent into which will
be made with two lifts, and a vessel
will traverse it in four hours.
'The Niagara and st. Lawrence riv-
ers will be improved, no canals or
| locks being necessary until the Corn
wall canal is reached The summit
level of the Cornwall canal will be
improved, and. the descent therefrom
to Lake st. Francis made with one
lift of forty-eight feet. From the
| SnlIfhQo storm nf LAX n CT
els canal, to be called the Chateau
gay section,s will be made across the
valley of that name, descending to the
Champlain level with one lift of about
! ffty-two feet,
| "a oaral NH to l,,,ilt from tl,o louror.