hrane heard a sweet,
high-pitched trilling which came from a half-inch hole in the ground.
But he was not astonished by the place from which the trilling came. He
was astonished at the sound itself.

There was a cry behind them.

_"Mr. Cochrane! Doctor Holden!"_

They swung about. And there was Babs on the ground, just disentangling
herself from the sling. She had followed them out, after waiting until
they had left the airlock and could not protest.

Cochrane swore to himself. But when Babs joined them breathlessly, after
a hopping run over the hot ground, he said only:

"Fancy meeting you here!"

"_I--I couldn't resist it_," said Babs in breathless apology. "And you
do have guns. It's safe enough--oh, look!"

She stared at a bush which was covered with pale purple flowers. Small
creatures hovered in the air about it. She approached it and exclaimed
again at the sweetness of its scent. Cochrane and Holden joined her in
admiration.

In a sense they were foolishly unwary. This was completely strange
territory. It could have contained anything. Earlier explorers would
have approached every bush with caution and moved over every hilltop
with suspicion, anticipating deadly creatures, unparalleled monsters,
and exotic and peculiar circumstances designed to entrap the unprepared.
Earlier explorers, of course, would probably have had advice from famous
men to prepare them for all possible danger.

But this was a valley between snow-clad mountains. The river that ran
down its length was fed by glaciers. This was a temperate climate. The
trees were either coniferous or something similar, and the vegetation
grew well but not with the frenzy of a tropic region. There were fruits
here and there. Later, to be sure, they would prove to be mostly
astringent and unpalatable. They were broad-leafed, low-growing plants
which would eventually turn out to be possessed of soft-fleshed roots
which were almost unanimously useless for human purposes. There were
even some plants with thorns and spines upon them. But they encountered
no danger.

By and large, wild animals everywhere are ferocious only when desperate.
No natural setting can permanently be so deadly that human being will be
attacked immediately they appear. An area in which peril is continuous
is one in which there is so much killing that there is no food-supply
left to maintain its predators. On the whole, there is simply a limit to
how dangerous any place can be. Da