d at his vitals
and weighted his limbs to leaden uselessness. With a mighty effort he
raised his head to look up into the grinning yellow face of the guard,
and his thick neck muscles were taut gnarled ridges under the strain.

"Damn your hide!" he howled. "It's a trick. I'll break you in two for
this, you slob!"

His huge biceps tensed and his fists came up. But they came up slowly
and ineffectually, ponderous things he could scarcely lift. A great
roaring of rocket tubes was in his ears then, and the ethership screamed
off through the red mists while he dabbed futilely at the leering yellow
face. And vile curses rasped from between his set teeth at the laughter
of the guards.

* * * * *

Luke Fenton never had taken the trouble to learn or he would have known
something about this planet Vulcan on which he was a prisoner. As far
back as 1859, by Earth chronology, its existence within the orbit of
Mercury had been reported by one Lescarbault, a French physician. But
other astronomers had failed to confirm, in fact had ridiculed his
discovery, and it was not until some years after the establishing of
interplanetary travel in the first decade of the twenty-first century
that the body was definitely located.

Vulcan, the smallest and innermost of the planets, circles the sun with
great rapidity at a mean distance of twenty million miles. Its periods
of rotation and revolution are equal, so that it always presents the
same face toward the solar system's great center of heat and light--for
which reason one side is terrifically hot and the other, that facing
into outer space, unbearably cold.

There is no life native to the body, and mankind has found it possible
to exist only in the narrow belt immediately on the dark side of the
terminator, the line of demarcation between night and day. Here there
are the dense vapors, illuminated perpetually by refracted light from
the daylight side and by the internal fires of the planet itself, fires
which erupt at regular intervals through many fissures and craters. And
it is only under greatest hardship that man can exist even here, what
with the noxious gases and the extremes of heat and cold to which his
body it subjected. There is no natural source of water or of food, so
these essentials must of necessity be conveyed from Mars or Earth by
ethership.

In spite of all this, man has persisted in establishing himself in the
vapor belt of