The mag-lev transit tunnel smelled of ozone, crushed dark rock, and the cold metal tang of old empty pocket seals.
Two hundred and eighty meters beneath the cratered crust of Mare Tranquillitatis. The access tube was stretched into the dark like the hollow throat of an ancient underground serpent. Its walls were heavy with ribbed rings of pressed silver-steel-melted rock waste, anchored directly into the lunar bed-rock. Every fifty meters, an amber emergency bright light pulsed with a low, rhythmic flicker, throwing long, skeletal shadows across the dual superconductor rails that ran down the center of the floor.
Arthur Vance adjusted the magnetic lock on his boots. He felt the sharp clamp of magnetic soles biting into the steel deck plates. In the one-sixth gravity of the lunar inside, a sudden movement without anchoring could send a man floating helplessly toward the high-voltage channels running along the vaulted ceiling.
Behind him, Sergeant Major Miller was signaling his seven surviving riflemen into position. Their outside suits were scarred with shrapnel gouges and sealed with hasty epoxy patches. Even so, their movements were disciplined. They stacked behind the heavy ferro-concrete blast baffles that flanked the rail switch, resting their star-fire carbines across the notched barriers.
