the valleys and on the highlands, and resolved that I would find the
cause for these differences.

The authentic history of these Marsmen runs back through thousands of
years. I learned with interest the wonderful past life on this world.

There was once a time when people all mingled together and cultivated
the valleys. Each one by doing his part made it lighter for all. But
after many years a few schemers combined and by their inventive genius
succeeded in erecting vast sliding curtains over the valleys. These
curtains were supported from the tops of the ridges on each side and, by
their manipulation, the operators could keep the sunlight from any
particular part of the valley.

Then these shrewd Marsmen exacted tribute from the valley-toilers,
saying to them: "Give us a fifth part of your products, and we will give
you sunlight."

So the toilers gave them tribute willingly, knowing that they could not
live without sunlight. Then it came to pass that these toilers were
burdened by reason of their taxes and they prayed to the rich that they
might have sunlight at a lower price, but the rich replied:

"We cannot give you sunlight for less because it costs us much to keep
in repair our immense curtain systems across the valley." So the poor
toilers labored more and slept less, while the few rich on the
elevations built unto themselves more spacious homes and lived in
greater luxury all their days.

In process of time some of the shrewdest highlanders devised an