ALMOST AN ACCIDENT
“What’s that big, long
affair, jutting out so far from the locks?”
asked Blake, when the tug had approached nearer.
“That’s the central pier,”
the captain informed him. “It’s a
sort of guide wall, to protect the locks. You
know there are three locks at this end; or, rather,
six, two series of three each. And each lock
has several gates. One great danger will be that
powerful vessels may ram these gates and damage them,
and, to prevent this, very elaborate precautions are
observed. You’ll soon see. We’ll
have to tie up to this wall, or we’ll run into
the first protection, which is a big steel chain.
You can see it just ahead there.”
Joe and Blake, who had gotten all
the pictures they wanted of the approach to the lock,
stopped grinding away at the handle of the camera
long enough to look at the chain.
These chains, for there are several
of them, each designed to protect some lock gate,
consist of links made of steel three inches thick.
They stretch across the locks, and any vessel that
does not stop at the moment it should, before reaching
this chain, will ram its prow into it.
“But I’m not taking any
such chances,” Captain Watson informed the boys.
“I don’t want to be censured, which might
happen, and I don’t want to injure my boat.”
“What would happen if you did
hit the chain?” asked Blake. They had started
off again, after the necessary permission to enter
the locks had been signaled to them. Once more
Blake and Joe were taking pictures, showing the chain
in position.
“Well, if I happened to be in
command of a big vessel, say the size of the Olympic,
and I hit the chain at a speed of a mile and a half
an hour, and I had a full load on, the chain would
stop me within about seventy feet and prevent me from
ramming the lock gate.”
“But how does it do it?” asked Joe.
“By means of machinery,”
the captain informed him. “Each end of
the chain fender goes about a drum, which winds and
unwinds by hydraulic power. Once a ship hits
the chain its speed will gradually slacken, but it
takes a pressure of one hundred tons to make the chain
begin to yield. Then it will stand a pressure
up to over two hundred and fifty tons before it will
break. But before that happens the vessel will
have stopped.”
“But we are not going to strike
the chain, I take it,” put in Mr. Alcando.
“Indeed we are not,” the
captain assured him. “There, it is being
lowered now.”
As he spoke the boys saw the immense
steel-linked fender sink down below the surface of
the water.
“Where does it go?” asked Blake.
“It sinks down in a groove in
the bottom of the lock,” the captain explained.
“It takes about one minute to lower the chain,
and as long to raise it.”
“Well, I’ve got that!”
Blake exclaimed as the handle of his camera ceased
clicking. He had sufficient views of the giant
fender. As the tug went on Captain Watson explained
to the boys that even though a vessel should manage
to break the chain, which was almost beyond the bounds
of possibility, there was the first, or safety gate
of the lock. And though a vessel might crash through
the chain, and also the first gate, owing to failure
to stop in the lock, there would be a second gate,
which would almost certainly bring the craft to a
stop.
But even the most remote possibility
has been thought of by the makers of the great Canal,
and, should all the lock-gates be torn away, and the
impounded waters of Gatun Lake start to rush out,
there are emergency dams that can be put into place
to stop the flood.
These emergency dams can be swung
into place in two minutes by means of electrical machinery,
but should that fail, they can be put into place by
hand in about thirty minutes.
“So you see the Canal is pretty
well protected,” remarked Captain Watson, as
he prepared to send his tug across the place where
the Chain had been, and so into the first of the three
lock basins.
“Say! This is great!”
cried Blake, as he looked at the concrete walls, towering
above him. They were moist, for a vessel had
recently come through.
Now the tug no longer moved under
her own steam, nor had it been since coming alongside
the wall of the central pier. For all vessels
must be towed through the lock basins, and towed not
by other craft, but by electric locomotives that run
alongside, on the top of the concrete walls.
Two of these locomotives were attached
to the bow of the tug, and two to the stern.
But those at the stern were not for pulling, as Joe
at first supposed, for he said:
“Why, those locomotives in back
are making fast to us with wire hawsers. I don’t
see how they can push with those.”
“They’re not going to,”
explained Captain Watson. “Those in the
stern are for holding back, to provide for an emergency
in case those in front pull us too fast.”
“Those who built the Canal seem
to have thought of everything,” spoke Blake
with much enthusiasm.
“You’ll think so, after
you’ve seen some more of the wonders,”
the tug captain went on with a smile. “Better
get your cameras ready,” he advised, “they’ll
be opening and closing the gates for us now, and that
ought to make good pictures, especially when we are
closed in the lock, and water begins to enter.”
“How does it come in?” asked Joe.
“Over the top?”
“No, indeed. They don’t
use the waterfall effect,” answered Blake, who
had been reading a book about the Canal. “It
comes in from the bottom; doesn’t it, Captain
Watson?”
“Yes, through valves that are
opened and closed by electricity. In fact everything
about the lock is done by electricity, though in case
of emergency hand power can be used. The water
fills the lock through openings in the floor, and
the water itself comes from Gatun Lake. There,
the gate is opening!”
The boys saw what seemed to be two
solid walls of steel slowly separated, by an unseen
power, as the leaves of a book might open. In
fact the gates of the locks are called “leaves.”
Slowly they swung back out of the way, into depressions
in the side walls of the locks, made to receive them.
“Here we go!” cried the
captain, the tug began to move slowly under the pull
of the electric locomotives on the concrete wall above
them. “Start your cameras, boys!”
Blake and Joe needed no urging.
Already the handles were clicking, and thousands of
pictures, showing a boat actually going through the
locks of the Panama Canal, were being taken on the
long strip of sensitive film.
“Oh, it is wonderful!”
exclaimed Mr. Alcando. “Do you think—I
mean, would it be possible for me to—”
“To take some pictures?
Of course!” exclaimed Blake, generously.
“Here, grind this crank a while, I’m tired.”
The Spaniard had been given some practice
in using a moving picture camera, and he knew about
at what speed to turn the handle. For the moving
pictures must be taken at just a certain speed, and
reproduced on the screen at the same rate, or the
vision produced is grotesque. Persons and animals
seem to run instead of walk. But the new pupil,
with a little coaching from Blake, did very well.
“Now the gates will be closed,”
said the tug captain, “and the water will come
in to raise us to the level of the next higher lock.
We have to go through this process three times at this
end of the Canal, and three times at the other.
Watch them let in the water.”
The big gates were not yet fully closed
when something happened that nearly put an end to
the trip of the moving picture boys to Panama.
For suddenly their tug, instead of
moving forward toward the front end of the lock, began
going backward, toward the slowly-closing lock gates.
“What’s up?” cried Blake.
“We’re going backward!” shouted
Joe.
“Yes, the stern locomotives
are pulling us back, and the front ones seem to have
let go!” Captain Watson said. “We’ll
be between the lock gates in another minute.
Hello, up there!” he yelled, looking toward
the top of the lock wall. “What’s
the matter?”
Slowly the tug approached the closing
lock gates. If she once got between them, moving
as they were, she would be crushed like an eggshell.
And it seemed that no power on earth could stop the
movement of those great, steel leaves.
“This is terrible!” cried
Mr. Alcando. “I did not count on this in
learning to make moving pictures.”
“You’ll be in tighter
places than this,” said Blake, as he thought
in a flash of the dangers he and Joe had run.
“What’ll we do?”
asked Joe, with a glance at his chum.
“Looks as though we’d
have to swim for it if the boat is smashed,”
said Blake, who remained calm. “It won’t
be hard to do that. This is like a big swimming
tank, anyhow, but if they let the other water in—”
He did not finish, but they knew what
he meant. Slowly and irresistibly the great lock
gates were closing and now the tug had almost been
pulled back between them. She seemed likely to
be crushed to splinters.