Into a Trench
Tom cast a hasty glance over the mechanism
of the machine before he started to cross the stream
by the additional aid of the grippers, or spanners,
as he sometimes called this latest device.
Along each side, in a row of sockets,
were two long girders of steel, latticed like the
main supports of a bridge. They were of peculiar
triangular construction, designed to support heavy
weights, and each end was broadly flanged to prevent
its sinking too deeply into the earth on either side
of a gully or a stream.
The grippers also had a sort of clawlike
arrangement on either end, working on the principle
of an “orange-peel” shovel, and these
claws were designed to grip the earth to prevent slipping.
The spanners would be pulled out from
their sockets on the side of the tank by means of
steel cables, which were operated from within.
They would be run out across the gap and fastened
in place. The tank was designed to travel along
them to the other side of the gap, and, once there,
to pick tip the girders, slip them back into place
on the sides, and the engine of war would travel on.
“You are mightily excited, Tom.
“I admit it, Ned. You see,
I have not tried the grippers out except on a small
model. They worked there, but whether they will
work in practice remains to be seen. Of course,
at this stage, I’m willing to stake my all on
the results, but there is always a half-question until
the final try-out under practical conditions.”
“Well, we’ll soon see,”
said one of the workmen. “Are you ready,
Mr. Swift?”
“All ready,” answered Tom.
Tank A, as she was officially known,
had come to a stop, as has been said, on the very
edge of Tinkle Creek. The banks were fairly solid
here, and descended precipitously to the water ten
feet below. The shores were about twenty feet
apart.
“Suppose the spanners break
when you’re halfway over, Tom?” asked
his chum.
“I don’t like to suppose
anything of the sort. But if they do, we’re
going down!”
“Can you get up again?”
“That remains to be seen,”
was the non-committal reply. “Well, here
goes, anyhow!”
Going up into the observation tower,
which was only slightly raised above the roof of the
highest part of the tank, Tom gave the signal for
the motors to start. There was a trembling throughout
the whole of the vast structure. Tom threw back
a lever and Ned, peering from a side observation slot,
beheld a strange sight.
Like the main arm of some great steam
shovel, two long, latticed girders of steel shot out
from the sides of the tank. They gave a half
turn, as they were pulled forward by the steel ropes,
so that they lay with their broader surfaces uppermost.
Straight across the stream they were
pulled, their clawlike ends coming to a rest on the
opposite bank. Then they were tightened into
place by a backward pull on the operating cables,
and Tom, with a sigh of relief, announced:
“Well, so far so good!”
“Do we go over now?” inquired Ned.
“Over the top—yes,
I hope,” answered Tom, with a laugh. “How
about you down there?” he called to the engine
room through a telephone which could only be used
when the machinery was not in action, there being
too much noise to permit the use of any but visual
signals after that.
“All right,” came back
the answer. “We’re ready when you
are.”
“Then here we go!” said
Tom. “Hold fast, Ned! Of course there’s
no real telling what will happen, though I believe
we’ll come out of it alive.”
“Cheerful prospect,” murmured Ned.
The grippers were now in place.
It only remained for the tank to propel herself over
them, pick them up on the other side of Tinkle Creek,
and proceed on her course.
Tom Swift hesitated a moment, one
hand on the starting lever and the other on the steering
wheel. Then, with a glance at Ned, half whimsical
and half resolute, Tom started Tank A on what might
prove to be her last journey.
Slowly the ponderous caterpillar belts
moved around on the sprocket wheels. They ground
with a clash of steel on the surface of the spanners.
So long was the tank that the forward end, or the
“nose,” was halfway across the stream
before the bottom part of the endless belts gripped
the latticed bridge.
“If we fall, we’ll span
the creek, not fall into it,” murmured Ned,
as he looked from the observation slot.
“That’s what I counted
on,” Tom said. “We’ll get out,
even if we do fall.”
But Tank A was not destined to fall.
In another moment her entire weight rested on the
novel and transportable bridge Tom Swift had evolved.
Then, as the gripping ends of the girders sank farther
into the soil, the tank went on her way.
Slowly, at half speed, she crawled
over the steel beams, making progress over the creek
and as safely above the water as though on a regularly
constructed bridge.
On and on she went. Now her entire
weight was over the middle of the temporary structures.
If they were going to give way at all, it would be
at this point But they did not give. The latticed
and triangular steel, than which there is no stronger
form of construction, held up the immense weight of
Tank A, and on this novel bridge she propelled herself
across Tinkle Creek.
“Well, the worst is over,”
remarked Ned, as he saw the nose of the tank project
beyond the farthermost bank.
“Yes, even if they collapse
now nothing much can happen,” Tom answered.
“It won’t be any worse than wallowing down
into a trench and out again. But I think the spanners
will hold.”
And hold they did! They held,
giving way not a fraction of an inch, until the tank
was safely across, and then, after a little delay,
due to a jamming of one of the recovery cables, the
spanners were picked up, slid into the receiving sockets,
and the great war engine was ready to proceed again.
“Hurrah!” cried Ned.
“She did it, Tom, old man!” and he clapped
his chum resoundingly on the back.
“She certainly did!” was
the answer. “But you needn’t knock
me apart telling me that. Go easy!”
“Bless my apple pie!”
cried Mr. Damon, who was as much pleased as either
of the boys, “this is what I call great!”
“Yes, she did all that I could
have hoped for,” said Tom. “Now for
the next test.”
“Bless my collar button! is there another?”
“Just down into a trench and
out again.” Tom said. “This
is comparatively simple. It’s only what
she’ll have to do every day in Flanders.”
The tank waddled on. A duck’s
sidewise walk is about the only kind of motion that
can be compared to it. The going was easier now,
for it was across a big field, and Tom told his friends
that at the other end was a deep, steep and rocky
ravine in which he had decided to give the tank another
test.
“We’ll imagine that ravine
is a trench,” he said, “and that we’ve
got to get on the other side of it. Of course,
we won’t be under fire, as the tanks will be
at the front, but aside from that the test will be
just as severe.”
A little later Tank A brought her
occupants to the edge of the “trench.”
“Now, little girl,” cried
Tom exultingly, patting the rough steel side of his
tank, “show them what you can do!”
“Bless my plum pudding!”
cried Mr. Damon, “are you really going down
there, Tom Swift?”
“I am,” answered the young
inventor. “It won’t be dangerous.
We’ll crawl down and crawl out. Hold fast!”
He steered the machine straight for
the edge of the ravine, and as the nose slipped over
and the broad steel belts bit into the earth the tank
tilted downward at a sickening angle.
She appeared to be making the descent
safely, when there was a sudden change. The earth
seemed to slip out from under the broad caterpillar
belts, and then the tank moved more rapidly.
“Tom, we’re turning over!”
shouted Ned. “We’re capsizing!”