Aberdeen herald. [volume] (Aberdeen, Chehalis County, W.T.) 1886-1917, 1913-11-04

other points to less severe pressure.
Engineers consider the dam excess
sively safe. and the layman has no diff
ficulty in approaching i strength.
About half of the mate.la, required,
22.504,OO0 cubic yards. has been
fought from the Culebra cut On July
1918. the dam was more than 90 per
cent completed. leaving less than per
cent to be done before the passage Of
the first ship.
On the Pacific size the first dam to
be encountered Is at Pedro Miguel and
serves to hold the waters Of Gatun
lake at its southern end. 1t Is 1,4OO
feet long and forty feet wide at the
top. The maximum height Of the water
against this dam will be forty feet
The plan Of construction Is much the
same as at Gatun. but only 100000
cubic yards will be required.
After a ship Is lowered thirty feet
by the Pedro Miguel lock It 6nds It.
self in an artificial lake a mile and
half long. This lake II formed by two
dams. the one to the west being $500
feet long and forty feet wide at the
top. holding a maximum head Of wa.
ter of forty feet. 1t Is constructed with
a hydraulic core like the Gatun dam.
On the east concrete dam 800 feet
long and provided with a spillway. as
at Gatun. and capable of discharging
1900 cubic feet Of water per second
will hold the small lake in control
The Cocoli river is the principal feed
er Of this lake.
Records kept by the French and by
the Americans since 1904 show con-
clusively that enough water always
will be available to keep the Gatun
lake and the tiny Miraflores lake ade-
quately supplied with water. No trou.
bic at all can develop during the eight
months of rainy season. and In the dry
season Of four months enough water
will have been stored in the lake by
means Of the regulating works in the
Gatun dam spillway to allow for all
losses through evaporation. seepage.
power consumption and loss through
the locks. During the wet season the
lake will be raised from elevationSS5
for two feet to elevation 81 over an
area Of 1874 square miles This water
could be used until the lake falls to
about eighty-two feet. Or Eve feet over
the lt4 square miles. In an average
dry season this would permit dfty-
eight complete transits Of the canal
every twenty four hours If the full
1000 foot capacity Of the locks we're
used or more than the period would al
low II vessels followed at intervals of
one hour.
The Gatun lake Is backed up among
the bills by the dam until It reaches
width Of more than twenty miles at
the widest point and length between
Gatun and Pedro Miguel Of thirty.two
miles. 1t will be broken by many
small islands and stretches Of high
lands and is narrowest In the Cuiebra
cut. where for nine miles the width 10
300 feet From Gatun to the entrance
Of tho cut. distance Of twenty three
manding points to guide ships at night
The channel throughout = at an aves-
age depth Of forty-h feet In order
to raise the relocated PAM ma railroad
above the level Of the lake It was nee.
essary to make oils TO the extent Of
1925. 292 cubic yards.
The navy department has selected q
site near San Pablo. about twenty
miles inland from the Atlantic and
on the east side Of Gatun lake. for q
high power wireless station. It 10 to
be at an elevation Of 40 feet above
the level of the lake and capable of
sending a message for 5000 miles. to
Washington or to a similar station on
the California coast
II the great Gatun dam should break
the water In the lake might sweep dev-
astatingly over the city Of Colon. seven
miles away. or pass through the old
bed Of the Chagres river harmlessly
into the Caribbean sea. While the
pressure on the dam will be terrific. no
such catastrophe Is considered proba
BILE The Gatun lake Is the largest ar.
ti6ciaI body Of water In the world.
Wrecks Or accidents in the lake or
locks will be handled by monster 270
ton floating cranes.
CONTINUED In next issue)