The Great Dome on Mercury

Darl Thomas mopped the streams of perspiration from his bronzed face
and lean-flanked, wiry body, nude save for clinging shorts and fiber
sandals. "By the whirling rings of Saturn," he growled as he gazed
disconsolately at his paper-strewn desk. "I'd like to have those
directors of ITA here on Mercury for just one Earth-month. I'll bet
they wouldn't be so particular about their quarterly reports after
they'd sweated a half-ton or so of fat off their greasy bellies.
'Fuel consumption per man-hour.': Now what in blazes does that mean?
Hey, Jim!" He swiveled his chair around to the serried bank of
gauge-dials that was Jim Holcomb's especial charge, then sprang to his
feet with a startled, "What's the matter?"

The chunky, red-haired control-man was tugging at a lever, his muscles
bulging on arms and back, his face white-drawn and tense. "Look!" he
grunted, and jerked a grim jaw at one of the dials. The long needle
was moving rapidly to the right. "I can't hold the air pressure!"

"Wow, what a leak!" Darl started forward. "How's it below, in the
mine?"

"Normal. It's the Dome air that's going!"

"Shoot on the smoke and I'll spot the hole. Quick, man!"

"Okay!"

Thomas' long legs shot him out of the headquarters tent. Just beyond
the entrance flap was one of the two gyrocopters used for flying
within the Dome. He leaped into the cockpit and drove home the
starter-piston. The flier buzzed straight up, shooting for the misted
roof.

* * * * *

The Earthman fought to steady his craft against the hurricane wind,
while his gray eyes swept the three-mile circle of the vault's base.
He paled as he noted the fierce speed with which the white smoke-jets
were being torn from the pipe provided for just such emergencies. His
glance followed the terrific rush of the vapor. Big as a man's head, a
hole glared high up on the Dome's inner surface. Feathered wisps of
tell-tale vapor whisked through it at blurring speed.

"God, but the air's going fast," Darl groaned. The accident he had
feared through all the months he had captained Earth's outpost on
Mercury had come at last. The Dome's shell was pierced! A half-mile
high, a mile across its circling base, the great inverted bowl was all
that made it possible for man to defy the white hell of Mercury's
surface. Outside was an airless vacuum, a waste quivering under the
heat of a sun thrice the size it appears from Earth. The silvered
exterior of the hemisphere shot back the terrific blaze; its
quartz-covered network of latticed steel inclosed the air that all
beings need to sustain life.