r the predictions of disaster for
crops, of danger from winter snows if the drop continued?"

Russ went on in his careful, explanatory way. "And for Mars it has
continued. Mars was always colder than Earth; life there must have been
far more precariously balanced. During the day, on the Martian equator
in midsummer, the highest temperature is not likely to be more than 70 deg.
or 80 deg.; and at night, even then, it would fall below freezing.
Vegetation on Mars must have been hardy in the best of times, and life
carried on under great difficulties.

"Now the margin of warmth and light has been cut. It has been just
enough to keep both polar caps frozen, to prevent water from reaching
the fertile regions, and the cold has advanced enough to bar the growth
and regeneration of plant life. If the Sun-tapping on Mars is not
stopped, all life there will die out, and it will be a permanently dead
world forever."

The news spread throughout the crew and there was a feeling of anger and
urgency. Nobody knew what lived on Mars, yet the subject of Mars and
Martians had always intrigued the imaginations of people on Earth. Now,
to hear that the unknown enemy had nearly slain a neighboring world
brought home vividly just what would also have been the fate of Earth.

The day finally came when the big spaceship slid into an orbit about the
ruddy planet. It circled just outside the atmospheric level while the
men aboard studied the surface for its secrets.

Mars was indeed inhabited. This fact was borne home by the canals and
the very evident artificial nature of their construction. They could see
clearly through their telescopes that there was an intricate global
network of pipelines, pumping stations, and irrigation viaducts from
pole to pole. They also saw that at the intersections of the canals were
dark sections crisscrossed with thin blobs of gray and black which
proved under the telescopes to be clusters of buildings. There were
cities on Mars, linked by the waterways.

They saw no aircraft. They detected no railroad lines or roadways beyond
the canalways themselves. The many regions of darker, better ground,
intersected by the canals which no longer fulfilled their purposes, were
covered with thick vegetation--forests of dying, wintery stalks. Only a
flicker of dark green here and there showed where some faint irrigation
still got through.

They saw also that there were lines of white, which had not been visible
before.