plants will shelter innumerable tiny
creatures, and some of them will be burrowers. So rain will drain
quickly into those burrowings and not make streams. And therefore the
drainage will reappear as springs, and the grazing animals will go to
those springs to drink. Often, they will gather more densely at
nightfall for greater protection from their enemies. They will even
often gather at the springs or their overflowing brooks. This will
happen anywhere that plains and animals exist, on any planet to the edge
of the galaxy, because there are laws for living things as well as
stones.

Great dark masses of the beasts moved unhurriedly past the ship. They
were roughly the size of cattle--which itself would be determined by the
gravity of the planet, setting a maximum favorable size for grazing
beasts with an ample food-supply. There were thousands and tens of
thousands of them visible in the deepening night. They crowded to the
gushing spring and to the stream that flowed from it. They drank.
Sometimes groups of them waited patiently until the way to the water was
clear.

"Well?" said Jones.

"I think you filled my order," admitted Cochrane.

The night became starlight only, and Cochrane impatiently demanded of Al
or somebody that they measure the length of a complete day and night on
this planet. The stars would move overhead at such-and-such a rate. So
many degrees in so much time. He needed, said Cochrane--as if this order
also could be filled--a day-length not more than six hours shorter or
longer than an Earth-day.

Jones and Al conferred and prepared to take some sort of reading without
any suitable instrument. Cochrane moved restlessly about. He did not
notice Johnny Simms. Johnny had stood sullenly in his place, not moving
to look out the windows, ostentatiously ignoring everything and
everybody. And nobody paid attention! It was not a matter to offend an
adult, but it was very shocking indeed to a rich man's son who had been
able to make a career of staying emotionally at a six-year-old level.

Cochrane's thoughts were almost feverish. If the day-length here was
suitable, all his planning was successful. If it was too long or too
short, he had grimly to look further--and Spaceways, Inc., would still
not be as completely a success as he wanted. It would have been much
simpler to have measured the apparent size of the local sun by any means
available, and then simply to have timed the intervals between its