Immediately Cliff and Val were on their feet, glancing at each other.
"Guess they must have hit something vital," Val said briefly.
He started to move forward as he spoke, Cliff beside him. At the pit top Cliff elbowed his way through the men.
"What's wrong below? What's happened?"
The radio operator in contact with below glanced up.
"Number 4 unit operating in underground cavern has encountered a steel wall, sir. Want your advice . . ."
"Steel wall? Down there!" Cliff looked his amazement. "But how the devil did—"
"Oh be damned to conjectures; let's go," Val snapped, and strode forward into the waiting shaft cage. He waited until Cliff had joined him, then threw in the switches.
For several minutes they dropped steadily down through the miles of shafting thrust deep into the planet's bowels. At last they touched bottom, flung back the grille, then hurried over to the group of engineers gathered round their enormous boring machine. It had stopped before a massive rotunda of gray metal stretching up into the cavern ceiling and on either side as far as the eye could see.
Richardson, the engineer in charge, nodded to the barrier as Cliff came up.
"Thought it was anilum[1] at first, Cliff, but our tests show it is steel of sorts. All in one piece; been flowed together by some skilled process. No sign of a join. Thought you'd better see it before we tried blasting it through. Might be something dangerous on the other side."
Cliff surveyed it keenly. "Such as?"
"You never know. Maybe molten lava: even conserved water supplies. Might be anything. The Martians sure didn't mean it escaping whatever it is . . ."
Val drew at his noisy pipe. "Might even be Martian life behind it," he murmured. "I'm not fooling," he went on, seeing Cliff's doubting look. "After all, I figure the Martians must have gone somewhere, and we've seen no trace of life in the upper or surface regions since we landed on this hell-fired planet."
Cliff tugged out his ray gun and fired it experimentally at the barrier. The metal sizzled and liquefied under the heat. He nodded curtly.
"O.K., start blasting it through. But take it easy and use a small radius. If there's anything dangerous released we'll have time to get clear anyway."
The big engineer gave the order. With Val beside him, Cliff mounted to the borer's flat deck and stood among the crew. In the belly of the ship's control room the men set about their tasks. The powerful tractors moved. A needle-pointed spear of incandescent heat stabbed the barrier and began to drive through it like a white-hot needle through a slab of butter. The air began to reek of heated metals and electric discharges.
At the end of a half-hour the reaction instruments showed the boring was finished. Immediately cooling radiations were forced through the barrier and searchlights were swung onto the foot-wide hole.
Staring into it the engineers could see nothing but darkness.
"There's air anyway," Val said, frowning. "Distinct draft blowing through."
"That might be the air blowing right through the planet from the other side,"
- ↑ Anilum is a metal which makes tungsten look like putty in comparison. Fredison, the space explorer, first discovered the stuff on Mars. Due to its extreme value, the United States sent Cliff Anderson to discover the mother lode if at all possible.—Ed.
