side--"

"Water?" Chet questioned.

"Yes; I saw a lake."

"Cover? Trees? Not the man-eating ones?"

"Everything: open ground, hills, woods. It looked good to me then; it
will look a lot better now," said Walt enthusiastically.

"Walk faster," said Chet; "I'm stepping on your heels."

* * * * *

They reached the valley floor some distance above the fumerole and the
clouds of poison gas; and the march began. The attack of the flying
reptiles had taught them the danger of exposure in the open, and they
kept close to the trees that fringed the valley.

Once Chet left them and vanished among the trees, to return with the
body of an animal slung over one shoulder.

"Moon-pig!" he told the others. "Ask Doctor Kreiss if you want to know
its species and ancestry and such things. All I know is that it has got
hams, and I am going to roast a slice or so before we start."

"Bow and arrow?" asked Harkness.

Chet nodded. "I'm a dead shot," he admitted, "up to a range of ten feet.
This thing with the funny face stood still for me, so it looks as if we
won't starve."

The sun had swung rapidly into the sky; it was now overhead. One half of
their first short day was gone. And Chet's suggestions of food met with
approval.

"I can't quite get used to it," Diane admitted to the rest; "to think
that for us time has turned back. We have been dropped into a new and
savage world, and we must do as the savages of our world did thousands
of years ago. Now!--in nineteen seventy-three!"

Chet removed a slab of meat from the hot throat of a tiny fumerole.
"Nineteen seventy-three on Earth," he agreed, "but not here. This is
about nineteen thousand B.C."

* * * * *

He called to Kreiss who was digging into a thin stratum of rock. The
scientist had a splinter of flint in his hand, and he was gouging at a
red outcropping layer.

"Old John Q. Neanderthal, himself!" said Chet. "What have you found,
silver or gold? Whatever it is, you're forgetting to eat; better come
along." But Doctor Kreiss had turned geologist, it was plain.

"Cinnabar," he said; "an ore of hydrargyrum!" His tone was excited, but
Chet refused to have his mind turned from practical things.

"Is it good to eat?" he demanded.

"_Nein, nein!_" Kreiss protested. "It is what you call
mercury--quicksilver!"

"Ladies and gentlemen," said Chet dryly, "I see where this man Kreiss is
to be a big help. He ha