n the masonry, and what was not crushed under
the caterpillar belts of the tank fell in a shower of bricks, stone and
cement on top of the machine.

Like a great hail storm the broken masonry pelted the steel sides and
top of the tank. But she felt them no more than does an alligator the
attacks of a colony of ants. Right on through the dust the tank
crushed her way. Added to the noise of the falling walls was that of
the machine guns, which were barking away like a kennel of angry hounds
eager to be unleashed at the quarry.

Ned kept his gun going until the heat of it warned him to stop and let
the barrel cool, or he knew he would jam some of the mechanism. The
other guns were firing, too, and the bullets sent up little spatter
points of dust as they hit.

"Great jumping hoptoads!" yelled Ned above the riot of racket outside
and inside. "Feel her go, Tom!"

"Yes, she's just chewing it up, all right!" cried the young inventor,
his eyes shining with delight.

The tank had actually burst her way through the solid wall of the old
factory, permission to complete the demolition of which Tom had secured
from the owners. Then the great machine kept right on. She fairly
"walked" over the piles of masonry, dipped down into what had been a
basement, now partly filled with debris, and kept on toward another
wall.

"I'm going through that, too!" cried Tom.

And he did, knocking it down and sending his tank over the piled-up
ruins, while the machine guns barked, coughed and spluttered, as Ned
and the others inside the tank held back the firing levers.

Right through the opposite wall, as through the one she had already
demolished, the tank careened on her way, to emerge, rather battered
and dust-covered, on the other side of what was left of the factory.
And there was not much of it left. Tank A had well-nigh completed its
demolition.

"If there'd been a nest of Germans in there," said Tom, as he brought
the machine to a stop in a field beyond the factory, "they'd have
gotten out in a hurry."

"Or taken the consequences," added Ned, as he wiped the sweat from his
powder-blackened and oil-smeared face. "I certainly kept my gun going."

"Yes, and so did the others," reported one of the mechanics, as he
emerged from the "cubby hole," where the great motors had now ceased
their hum and roar.

"How'd she stand it?" asked Tom.

"All right inside," answered the man. "I was wondering how she looks
from the outside."

"O