his feet.

"Oh, golly!" he exclaimed as the same thought occurred to him. "That
lizard----" He looked about him wildly.

"It was foolish perhaps." The Doctor spoke quietly. "But we can't help
it now. The sparrow has gone. That lizard may be right here at our
feet"--The Very Young Man jumped involuntarily--"and so small we can't
see it," the Doctor finished with a smile. "Or it may be a hundred miles
away and big as a dinosaur." The Very Young Man shuddered.

"It was senseless of us to let them get in here anyway," said the Big
Business Man. "That sparrow evidently has stopped getting smaller. Do
you realize how big it will be to us, after we've diminished a few
hundred more times?"

"We needn't worry over it," said the Doctor. "Even if we knew the lizard
got into the valley the chances of our seeing it here are one in a
million. But we don't even know that. If you'll remember it was still
some distance away from the scratch when it became invisible; I doubt
very much if it even got there. No, I think probably we'll never see it
again."

"I hope not," declared the Very Young Man emphatically.

For another hour they climbed steadily downward, making more rapid
progress than before, for the descent became constantly less difficult.
During this time they spoke little, but it was evident that the Very
Young Man, from the frequent glances he threw around, never for a moment
forgot the possibility of encountering the lizard. The sparrow did not
return, although for that, too, they were constantly on the look-out.

It was nearly half-past one when the Big Business Man threw himself upon
the ground exhausted. The valley at this time had reached a depth of
over ten thousand feet. It was still growing deeper, but the travelers
had made good progress and were not more than fifteen hundred feet above
its bottom.

They had been under tremendous physical exertion for over five hours,
too absorbed in their strange experiences to think of eating, and now
all three agreed it was foolish to attempt to travel farther without
food and rest.

"We had better wait here an hour or two," the Doctor decided. "Our size
will soon remain constant and it won't take us long to get down after
we've rested."

"I'm hungry," suggested the Very Young Man, "how about you?"

They ate and drank sparingly of the little store they had brought with
them. The Doctor would not let them have much, both because he wanted to
conserve their supply, and