Tensas gazette. [volume] (St. Joseph, La.) 1886-current, 1918-10-11
zo~ o<Maax cum eoAzy AEANuv DOCK noIs

hood period, 1t allows the river to flow
on uninterrupted, while during thu
navigation season Ii serves its full
purpose as dam and may be so Cd
Grated as to pass a large or small
quantity Of water, thus keeping each
pool at its proper level.
Highest Lift Locke
There are SO locks on the Erie
canal, all Of which are massive con-
crete structures. having inside rec.
tangular dimensions of 300 by 44.44
fees and lifting capacity varying
from few feet up to 4Oh feet. At
waterford the locks are so constructed
that a series Of five serves to lift the
barges from the Hudson river to the
canalized Mohawk river, 169 feet above
the level Of the government lock at the
Troy dam. These structures have
been called the worlds greatest series
OF high-lift locks and their lift is dou-
bic that of the locks In the Panama
canal from sea level to summit.
One Of the highest lift locks in the
world is located at Little Falls, where
the difference in pool elevation is 4Oh
feet This massive structure has con-
crete walls, which stand so feet high
and are 80 feet wide at the base. The
lower gate Is Of the lift type and is
raised and lowered, instead of being
swung open and shut as are the gates
on other locks.
In the operation Of all locks the wa
ter is admitted to and drawn from the
chamber by means of culverts rum
ming through the side walls, and the
openings have been so designed that
the filling and emptying of the cham
Der Is only matter of a few minutes.
The locks are all electrically OPP
Grated and the chambers are filed or
emptied while the gates and valves
are opened or closed by simply turn
ing a lever. Safety devices are also
arranged SO that errors in operation or
navigation are practically eliminated.
The Erie canal is spanned by 232
bridges. Of which so are railroad cross.
ings. The clearance under these struc-
lures must be at least 15% feet.
Guard Against Accident.
In the ''land line" guard gates have
been provided which are located about
ten miles apart. These are steel struc-
lures. suspended from towers and may
be lowered to hold the water, In case
Of emergency. such as might exist If an
embankment became weakened or any
similar accident made 1t desirable to
unwater any section Of the channel.
Numerous culverts and spillways
which keep the water from overflow
ing the banks bave been provided and
a hundred million yards of earth and
rock have been removed, while three
million yards Of concrete have been
placed.
Will, the actual construction period
has been about Is years. this, consider
ing the magnitude and ramifications of
the work. Is q very short time. The
many structures and the nature Of the
territory through which the different
channels ru has made this one of the
really important engineering undertake
ings Of the age, and the construction
details have been the most extensive,
the plans alone being some of the most
elaborate and complete ever drawn up
for any large construction work.
The cost Of handling freight on the
before recent increases went
into effect. varied from two to seven
mills per ton per mile. the average be-
Ing between three and six mills per
ton mile. It u now estimated that this
figure will be reduced more than one
half on the new canal system. owing to
he larger barges and the thoroughly
lp-to-date facilities. The method Of |
PROPULSION used Is by power boats |
lriven either by steam, electricity or |
he internal combustion engine. and II |
has already been determined from
rial trips that the speed which may be
throughout the system IL
,oncfAo~ot In ovNowo ~ thot main