metal fence. For some time he was unconscious.

* * * * *

When he had staggered painfully to his feet, it was night. The
monsters were gone; the starless sky was black and empty. Calling out
weakly, and stumbling about the pen, he found Agnes. She was chained
where Dr. Whiting had been.

She was conscious, unharmed. For a time they talked a little,
exchanging broken, incoherent phrases. Then they went to sleep, lying
on the anvil, beneath that mighty hammer that was slowly lifting to
strike another fearful blow.

When the "sun" had risen again, Larry brought Agnes some of the brown
soup from the metal urn, which had been filled again. Then, when he
had satisfied himself, he started clambering up the massive frame of
the hammer.

If he could put it out of commission!

It was a difficult task. He slipped back many times, and finally had
to choose another place to make the ascent. Twice he slipped and
almost fell from a considerable height. But finally he reached the
massive wheel of the valve which seemed to control the admission of
steam into the cylinder above the hammer.

If he could but close that, the steam would be confined in the chest
below. And when the pressure reached a certain point, something should
happen!

The valve was not easy to turn; it seemed fixed with the corrosion of
ages. For hours Larry wrestled with it. Then he left it, realizing
that he must find something to use for a hammer. A vigorous search of
the pen's hard earth floor failed to reveal any stone that would do.
He turned his attention to the machine, and presently saw a slender
projecting lever, high up on the side of the vast frame, which looked
as if it had been weakened by corrosion. After a perilous climb, he
reached the bar of green metal and swung his weight upon it. It broke,
and he plunged to the ground with the bar in his hands.

* * * * *

Clambering up once more to the great valve, he hammered it until the
rust that stiffened it was loosened. Then he struggled with the valve
until it was closed.

"We'll see what happens!" he muttered.

Returning to the ground, he set to work to break the green metal
fetters upon Agnes' wrists and ankles, using the broken lever as
hammer and file.

For the greater part of six days he toiled at that task, while the
great hammer rose slowly. But the green metal seemed very hard. One
arm was free at the end of the second