The watchman and southron. [volume] (Sumter, S.C.) 1881-1930, 1910-05-21

shaped piece out of it down to forty
feet above the seattle water surface
is to be at eighty-fve feet, but the ca
nal will be forty-five feet deep-and
to have the bottom Of that slice a full
800 feet wide. that is a good deal Of
job. One hundred million cubic yards
of rock and dirt, to be exact. One
can hardly realize the magnitude OF
the work without seeing it with his
own eyes.
THE French made a deep, narrow
cut at Culebra, and took out some
24,000,000 cubic yards of material.
When the Americans took hold their
operations weren't quite so spectacu-
lar. Before going any deeper they
extended the cut to practically it's full
width. That took several years. Then
they started down. They won't make
any official statements on the isthmus
now as to any probable dates of COM
pletion, but the unofficial statements
and they are usually as accurate
give only four years for the entire
completion Of the Culebra work. And
that and the Gatun dam and lock
work are the two points which will
be finished last
Between the cut and the Gatun
dam there will have to be little en-
cavation-merely the looping off OF a
few knolls here and there near the
rise OF the continental slope. For the
first eight miles in from Gatun there
will be no digging at ALL in and near
Bas Obispo, at the foot Of the hills,
the French did a good deal of exca-
waiting which will prove most useful.
But for all Of the twenty-three miles
of what will be open lake, the work
Is to all intents finished. The hardest
digging here was simpler even than
the work on several canals which
have been built in the Eastern States
There were a couple of rivers to con-
troll, rivers which would rise higher
than the canal excavations, but 1t was
only a matter of two or three feet,
and that was simple.
'The key pieces Of the whole canal
are the dams and locks-the dam and
double flight at Miraflores, the twin
single-lift lock at Pedro Miguel and,
more than both of these, the great
dam and triple flight Of locks at Ga
tun. The locks throughout the line
of the waterway will be uniform; the
two minor dams are but little out Of
the ordinary. And so a general de-
scription Of the work and progress at
Gatun should give fair idea Of the
whole work.
"Gatun is the Atlantic water gate
way Of the isthmus. Here 1t is that
two or three good sized rivers-the
Chagres and Gatuncilla and several
others-pour in together and swirl
out between two low-lying ranges Of
hills into the Caribbean. Back of
Gatun the country spreads out for
miles Of bog and swamp and soggy
morass, the territory which will form
the bed Of the new lake. Nature could
hardly have designed q better place
for a gigantic dam and spillway and
flight of locks.
ACROSS the $500 feet between
those two low ranges the dam Is be-
ing thrown-a dam 115 feet high and
nothing more or less than a big, easy
hill squarely across the valley. It is
neither the largest nor the most spec
tacular dam ever constructed, but
when you stand there and look it over
it seems like a pretty big proposition
That pile of rock and earth will have
head of only S5 feet of water
against 1t and that for about 500 feet
OF Its length, but it will hold a lake
the area of which will be over 164|
square miles.
Right in the middle of the valley
and incidentally, the dam, rises a
small hill of rock-Spillway hill, they
call 1t, because here a concrete lined
rock cut will take care Of the surplus
water which the rivers pour down
during the rainy season. The Spill
way is to have a channel 300 feet
wide designed for q run-off capacity
of 100000 cubic feet a second. That
is about finished; the cut has been
completed, the concrete floor is down,
and the walls themselves are we'll un-
der way.
West of Spillway hill little work
on the actual dam constructed has
been done; that's because there has
got to be some place for the rievrs to
run until they can be turned through
the Spillway itself. But on the east
Il,