50 in 50

He trudged downward, leaning forward as he pushed his way through the soupy limestone. It rushed through and around him like a strong current of water. It was getting harder every day to push through the stuff. The piezo crystal of his walk-through was steadily getting further away from the optimum frequency. It took a hard push to get the atoms of his body between those of the surrounding matter. He twisted his head around and blinked to focus his eyes on the two-inch oscilloscope screen set inside his helmet. The little green face smiled at him — the jagged wave-pattern gleaming like a row of broken teeth. His jaw clenched at the variations between the reading and the true pattern etched onto the surface of the tube. If the crystal failed, the entire circuit would be inoperative, and frozen death waited quietly in the air far above him for the day he couldn't go under. Or he might be underground when the crystal collapsed. Death was here, too, a quicker and much more spectacular death that would leave him stuck forever like a fly in amber. A fly that is part of the amber. He thought about the way Soft-Head had got his and shuddered slightly.

Soft-Head Samuels had been one of the old gang, the hard-bitten rock divers who had been the first to uncover the mineral wealth under the eternal Alaskan snows. Soft-Head had slipped off a hogback two hundred meters down and literally fallen face-first into the fabulous White Owl mother lode. That was the strike that started the rush of '63. As the money-hungry hordes rushed north to Dawson he had strolled south with a fortune. He came back in three years with no more than his plane fare and a measureless distrust of humanity.

He rejoined the little group around the potbellied stove, content just to sit among his old cronies. He didn't talk about his trip to the outside and no one asked any questions. The only sign that he had been away was the way he clamped down on his cigar whenever a stranger came into the room. North American Mining grubstaked him to a new outfit and he went back to tramping the underground wastes.

One day he walked into the ground and never came up again. "Got stuck," they muttered, but they didn't know just where until Pete walked through him in VI.

Pete remembered it, too well. He had been dog-tired and sleepy when he had walked through that hunk of rock that hadn't been all rock. Soft-Head was standing there — trapped for eternity in the stone. His face was horror-stricken as he stood half bent over, grabbing at his switch box. For one horrible instant Soft-Head must have known that something was wrong with his walk-through — then the rock had closed in. He had been standing there for seven years in the same position he would occupy for all eternity, the atoms of his body mixed inextricably with the atoms of the surrounding rock.

Pete cursed under his breath. If he didn't get enough of a strike pretty soon to buy a new crystal, he would become part of that timeless gallery of lost prospectors. His power pack was shot and his oxygen tank leaked. His beat-up Miller sub-suit belonged in a museum, not on active duty. It was patched like an inner tube and still wouldn't hold air the way it should. All he needed was one strike, one little strike.

His helmet light picked a blue glint from some crystals in the gully wall. It might be Ytt. He leaped off the granite spine he had been following and sank slowly through the lighter rock. Plugging his hand neutralizer into the socket in his belt, he lifted out a foot-thick section of rock. The shining rod of the neutralizer adjusted the vibration plane of the sample to the same frequency as his own. Pete pressed the mouth-shaped opening of the spectroanalyzer to the boulder and pressed the trigger. The brief, intensely hot atomic flame blazed against the hard surface, vaporizing it instantly.

The film transparency popped out of the analyzer and Pete studied the spectrographic lines intently. Wrong again, — no trace of the familiar Yttrotantalite lines. With an angry motion he stowed the test equipment in his pick and plowed on through the gummy rock.

Yttrotantalite was the ore and tantalum was the metal extracted from it. This rare metal was the main ingredient of the delicate piezoelectric crystals that made the vibratory mass penetrator possible. Ytt made tantalum, tantalum made crystals, crystals operated the walk-through that he used to find more Ytt to make… It was just like a squirrel cage, and Pete was the squirrel, a very unhappy animal at the present moment.

Pete carefully turned the rheostat knob on the walk-through, feeding a trifle more power into the circuit. It would be hard on the crystal, but he needed it to enable him to push through the jellylike earth.