Evening capital news. (Boise, Idaho) 1901-1927, 1912-11-18
garding excavation, placing of concrete.

garding excavation, placing Of concrete
erection Of dams and locks and sub.
sidary works are not as IVcent as
those contained in the regular monthly
reports. Naturally the most interest
ing feature of the report relates to tht
operations in. the great Culebra cut
Here, great landslides, many ranking
with an Alpine avalanche in magnitude
have SO increased the amount of ma.
terial to be excavated, that were 1t not
found possible to steadily reduce the
cost per yard Of dredging and steam
shoveling through the growing expert
ness OF the employees, and improved en-
cheering methods. the total cost OF
excavation would have been vastly
greater than the estimates. During the
last year nearly 16.500.OO0 cubic yards
of earth were taken out of this cut
leaving nearly 100000 to be dis
placed before the canal can be opened
The damage caused by the slides may
be appreciated from the fact that near
ly 100000 yards Of earth excavated
was so composed, or nearly SO per cent
of the total excavation.
There is only one way to deal with
these slides. and that is to dig then,
out as they occur, though some heir
is gained by terracing the upper banks
That Is because the geological forma :
ton changes so Frequently and sud
denly that no other effective treatment
has been found. So unstable is the
earth that the material In one part OF
the cut begins to move on an inclina-
ton as low as on Z. owing to the mass
CT stratiied rock sliding oyvr layer
CT Ignite. Gne slide now in motion
rear the bridge of Culebra, covers an
area of GO acres. from which 2,710,0 900
yards have already been removed, leav-
ing 100000 still to be handled.
Very Flat Slopes.
Then there Is another little slide OF
no less than so acres on the opposite
side Of the canal. The result of these
earth movements, which are quite ex-
ceptionai in engineering practice. has
been to leave the canal in its deepest
portions, with very flat slopes. The
encouraging feature Of the heavy work
at that point is found in the statement
in the report that none of the slides
which occurred during the year would
have in<erfered with the passage of
ships had the canal been in operation"
Already the appropriations made by
congress for the canal have run into
big figures, the total up to June 80 last
being $2S3,5B1,46S. and since that date
there have been additional appropria-
tons. exclusive OF those for fortifica-
tons, amounting to $28,9SO. 900, making
the grand total $322.541.46S. On June
so OF all these appropriations, the en-
gineers had expended 60 per cent OF the
total estimated cost OF the canal.
OF even greater interest from An en-
cheering point Of view, than the vast
but commonplace work Of excavation
in Culebra cut, was the work OF con-
structing the great locks at Gatun. and
Miraflores, and Pedro Miguel. for there
many novN problems have been solved.
ana lock machinery constructed OF spe-
cial designs Of q magnitude never be-
fore heard of. For instance. 10 big are
the valves at the side of the locks that
test showed that it required q pull OF
over ten tons on the stem to open one
OF these valves. All this work IL done
electrically. and here again the engi-
neers were confronted with new diffi-
cultics Owing to the peculiar climatic