They had heard of the legendary “Sun— children” from the Vulcanian natives, had once glimpsed one far off. But these two were nearer. Newton, straining his eyes against the solar glare, could barely see the things — two whirling little wisps of flame, moving fast through the blinding radiance of the corona.
Then the two will-o-wisps of fire had disappeared in the vast glare. The eye searched for them in vain.
“I still think”, Simon was saying, “that they’re just wisps of flaming hydrogen that are flung off the Sun and then fall back again.”
“But the Vulcanians told of them coming down into Vulcan”, Otho objected. “How could bits of flaming gas do that Curt NEWTON hardly listened. He was already whipping the ship in around Vulcan in a tight spiral few spacemen would have risked. Its brake rockets thundering, it scudded low around the surface of the little world.
The whole surface was semi-molten rock. The heat of the planetoid’s stupendous neighbor kept its outer skin half-melted. Lava sweltered in great pools, infernal lagoons framed by smoking rock hills. Fire burst up from the rocks, as though called forth by the nearby Sun.
Grag first saw what they were looking for — a gaping round pit in the sunward side of the planetoid. Presently Captain Future had the Comet hovering on keel-jets above the yawning shaft. He eased on the power-pedal and the little ship dropped straight down into the pit.
This shaft was the one way inside the hollow solar satellite. At the planetoid’s birth gases trapped within it had caused it to form as a hollow shell. Those gases, finally bursting out as pressure increased, had torn open this way to the outer surface.
The ship sank steadily down the shaft. Light was around them for this side of Vulcan was toward the Sun now and a great beam entered.
Then, finally, the shaft debouched into a vast space vaguely lighted by that beam — the interior of the hollow world.
“Whew, I’m glad to be in here out of that solar radiance”, breathed Otho. “Now where?”