at forms part of Gatun
Dam. Here one hundred and forty thousand cubic feet of water can be
discharged every second. The waters made a magnificent picture as they
poured through the gates. As Dick remarked, it was "an abridged edition
of Niagara Falls." At the east of the spillway, was the power plant,
where the water, dropping seventy-five feet, developed enough electric
power and light to operate the canal from end to end.

At Bohio, the southern end of Gatun Lake, they came to the place where
the canal enters the foothills of the mountain range. Up to this point,
there had been but little digging, but here the real work of excavation
had begun. The earth and rock that had to be removed here was equal to
that involved in cutting a ditch across the United States, ten feet deep
and fifty-five feet wide. The dirt would load a train that reached four
times around the earth.

"Only a little matter of a hundred thousand miles," exclaimed Tom. "Gee,
these figures are enough to make your head ache. Everything is in
thousands and hundreds of thousands and millions."

"Yes," said Bert, "it's simply inconceivable. We mention figures, but we
can't really grasp what they mean. It seems like the work of giants,
rather than men."

"Right you are," assented Dick. "Why, even the blast holes drilled for
the dynamite, if put together, would stretch from New York to
Philadelphia."

At the great Culebra Cut, where at one point the depth was over four
hundred feet, the wonder grew. Twenty million pounds of dynamite had
been used in this cut and the cost of the excavation was over eighty
millions of dollars. Yet with such care and skill had this been managed
that very few men had lost their lives; not as many as are killed in the
erection of an ordinary office building in New York.

And here, at Culebra, the problem had been harder to solve than anywhere
else. There had been enormous landslides, that made it necessary to do
the work over and over again. Twenty-one million cubic yards of earth
had fallen from the mountain side, in many cases covering the engines and
shovels engaged in the work of excavation. One slide involved
sixty-three acres. At another place, forty-seven acres moved entirely
across the Canal at the rate of fourteen feet a day, and rose at one
point to a height of thirty feet. Over twenty times, these avalanches
came down the sides of the cut. It seemed as though Nature were angered
at the attem