The San Francisco call., 1910-07-31

pace is less than 500 yards wide, one
must either see the work or be an ex-
perienced engineer.
That the efficiency OF the labor used
is constantly on the upward grade is
shown by figures obtained at the office
of the central division engineer, who
has charge OF the operations at Guile
bra cut The total amount OF dynamite
consumed during one month of this
year as compared with the same month
of last year shows 375,600 pounds used
iE excavating rock as against the 1909
figure OF 625,150 pounds. Even at this
more rock was excavated with the
smaller quantity Of dynamite, the av-
erage being 3.02 cubic yards of rock rer
pound of explosive for this year as COM
pared with Leg cubic yards per pound
last year
This gain in efficiency in handling
dynamite amounts to 81 per cent in
rock excavated per one pound Of ex-
plosive, and means a great saving to
the government The results are
ul6nly SIdlAly 4HS " lnC Oll4NAoAS Ia
charge.
Along the Culebra cut, where the
ponderous steam shovels are at work
filing the dump cars, a sort Of rivalry
has sprung UP. The operators Of the
shovels endeavor to break records, and
this helps toward the great goal-get-
ting rid of the dirt and stone.
work as they are today is to realize
the impossibility of completing a canal
across the isthmus through any other
means. The tools which were avail
able 80 years ago would not be equal
to the mighty task of cutting the
CuIebra cut through the stone and dirt.
A record made this year by one steam
shovel working In the Culebra cut
shows that 70,29o cubic yards OF rock
were excavated in 2s days, wonderful
feat in itself The best accomplished
in a single day was 1923 cubic yards.
This is equal to the work of small
army Of men with picks and shovels.
The Suez canal was built by natives
carrying the soil out in sacks. This
would be simply impossible at Panama.
A record of Is steam shovels which
worked eight hours day for 26 days
one month this year in the Culebra cut
showed a total excavation OF more
cubic yards OF dirt and rock than any
previous month. On April IL these
shovels accomplished the most, when in
all 29,201 cubic yards were excavated.
In a recent issue OF the Canal Rec
ord, the official weekly published un-
der the authority of the isthmian canal
commission at Ancon, figures were pre-
sented which showed that the canal as
originally planned in the report of the
minority of the International board of
engineers and adopted by congress had
been dug. This was total Of approx
imately o3,O0o,000 cubic yards.
Changes in the plan made subsequently
by order of the president brought the
total UP to approximately 175.0Oo.ooo
cubic yards.
Two slides of earth and rock into
Culebra cut have caused considerable
inconvenience to the Americans. These
are located at Cucaracha and the vii
lage of Culebra. Three steam shovels
are necessary to handle the material
which falls into the cut and a bench
at 10 feet above the sea level has been
made along the cut, where the steam
shoyels dump the mixture of dirt and
rock into cars to be carried away.
1t is said that this movement of the
hillside into the cut began as early as
1884, when the French were at work on
the canal. In all close to 1,S50,000
cubic yards have slid as a result Of
the movement, which is caused by a
mass of rock and stone slipping on a
smooth substratum OF rock, the move
ment being perceptible at all times Of
the year.