South Bend news-times., 1913-11-27

| mits they could work a number Of
eXcavators simultaneously at several
points. so that a succession Of benches
or ledges resulted, lying one above
the other, each with the natural sur
face at the point Of beginning. By
working in the direction cf the length
of the cut, the face Of the bank gave
the longest cutting possible, reducing
the number of times the excavator
must be hauled back, and secured a
satisfactory drainage arrangement.
since the cutting was carried up grade
on either side OF the summit
The Americans followed the same
method, the only difference being in
the character of machinery used.
The greatest difficulty encountered
in the excavation was due 10 slides
and breaks which caused large masses
OF material 10 slide or move into the
excavated area, closing off the drain
age, upsetting steam shovels and tear
ing up the tracks.
The term slide" is applied TO the
movement OF the everything clay upon
smooth, sloping surfaces OF rock or
other material harder than clay.
Breaks" occur at points where the
underlying rock is OF poor quality. in
tersected by vertical seams or seams
sloping toward the canal. and which
is unable TO bear up the superimposed
mass Generally the upper surface
of the broken portion of the bank re-
mains approximately horizontal.
settling nearly vertically. The weight
of the broken portion forces up and
displaces laterally the material lying
directly below ii in the bottom or on
the berms or lodges Of the canal. AS
the material thus forced up is taken
away the upper part gradually settles
and moves towards the axis of the
canal until the entire broken portion
Is removed.
The greatest slide was at Cucaracha
and gave trouble when the French be-
gan cutting in 1884. Though at first
confined TO a length of 500 feet meas
ured along the line of excavation, the
slide extended TO include the entire
basin south OF Gold Hill. This slide
was the last obstruction to the canal
and it's removal was the opening that
finally makes the canal an accomplish
ed fact.
There were, all told, nine slides and
breaks to be reckoned with, and there
was nothing to do but remove all the
material embraced within their limits.
There is no other method known TO
stop or prevent them. No apprehen-
sion is felt because of the slides in
the future of the canal. They devel-
oped as the depth Of the cut increased,
and the banks slid or broke because
of the condition of unstable equilib-
rum. When the grade was reached,
equilibrium was established and the
back pressure of the water results in
greater stability.
Work has been in progress in the
Culebra cut since 1880, and during
the French control 1886, 600 cubic
yards were removed. eBtween Gatun
and Bas Obispo. the northern end of
the Culebra cut, the French eXcava-
ton which was useful to the present
project amounted to 2,201,0 900 cubic
yards or total in the Central divi-
sion of over 90, 900 cubic yards.
Some idea Of the magnitude Of the
operations may be formed from the
fact that this division had withiI its
Jurisdiction over 200 miles of five-foot
gauge track laid, about SO miles of
which were within the side slopes Of
the Culebra cut alone.
GEO. w. COCKTAILS.
The third and concluding chapter
of Col. Goethals' story will be printed
In this newspaper tomorrow.