Atlanta Georgian. [volume] (Atlanta, Ga.) 1912-1939, 1913-09-21

striking clearness how much bigger
the job was than anything engineers
had ever tackled up to ten years ago.
The digging of Culebra Cut has. for
one thing, given the engineering world
new set of standards by which to
measure the requirements of future
works of a similar character.
1t was estimated in the beginning
that $4,000 900 cubic yards of earth
would have to be taken out of the
Culebra Cut, not counting the 24,000,-
600 cubic yards removed by the
French. Yet next spring will see
more than twice that amount of ma
terial dug out of the cut The original
estimate of the international board of
advisory engineers as to the amount
to be taken out If a sea level canal
were constructed was only 100000
cubic yards in excess of what has ac-
tually been removed for a lock canal
the bottom of which is As feet above
sea level
IS ShoVeIs at Work.
It was then estimated that the cut
would accommodate 100 steam SHOW
els in operation. Experience has
shown that the maximum number
which could work at one time in the
cut was 46. and no one has ever chided
Colonel Goethals for not digging in
dustriously. Yet had the original es
innate Of the capacity Of these steam
shoVelS been verified by experience
the United States would he to-day
looking forward to a celebration of
the opening of the Panama Canal in
1926, instead of in 1914 or 1915. So
great has been the increase of eff
cheney among the canal builders that
even though the estimate of total ex-
caVation has been increased from
time to time until more than 100000,
600 cubic yards have been added, not
single day has been added to the
time required for the digging nor
single dollar added to the cost. 1t
was largely the men at work in Guile
bra Cut who made possible this viz
tual gift Of 100, 900, 900 cubic yards of
excavation thrown into the Job extra.
The slides alone in Culebra Cut
added about 100000 cubic yards
to the work of the diggers there. If
all the horses in the United States
were hitched up to wagons contain
ing the material dumped into the cut
by slides they would not be able to
move 1t an inch. Think of a farm
of 81 acres sliding downhill into the
partially completed cut at one time.
l'Think of this happening not once but
scores of times though usually on
somewhat smaller scale.
Cucurache Oldest Slide.
The CucuraChe slide alone has
added 10000 cubic yards to the eX
cavators' task, while the Culebra
slide has brought in more than 5000,
600 cubic yards more. The canal en-
gineers have records of more than
score of important slides. great
masses Of the banks of the cut which
| have been in motion almost ever
since the Americans took up the
business of canal digging.
The Cucurache slide is the oldest
and the most active of all the slides.
1t began in July, 1905 when cracks
and assures were noticed far UP the
banks OF the cut. It hasn't stopped
sliding vet and will not until the
slope of the banks has been reduced
sufficiently to tighten the pressure.
There Is only one method OF treat
ment of slides. that Is to dig the ma
terial out as fast as it slides In. The
| canal workers became so accustomed
| TO slides that when a million or more
| cubic yards of earth fell into the big
Glitch" burying steam shovels and
railroad tracks and sometimes whole
| trains 30 feet deep they calmly pro-
Ceeded to dig everything out again
Sometimes the SlueS moved DIS Idplu-
! " as four feet in II minutes and
often workmen engaged in digging
! out a slide continued at their work
with great danger to their own lives.
Two Causes Responsible.
| The biologists have divided the
/ slides into four kinds, due to two
| causes. The causes, are first, the
weak and unstable condition Of the
| rocks of the cut, attributable solely
| to nature, and second. the oversteep-
ness and height Of the wall of the cut,
| the blasting and other works due en-
| tirelv to man. The four kinds of
slides are the structural breaks, the
most common and most difficult TO
deal with; the normal or gravity
slides, the fault zone slides, and
J fourth, the weathering and erosion
slides. 1t has been found necessary