ned air in
the tunnel told of a door slammed behind them.

Judson broke into a stumbling run, and then stopped short in increasing
bewilderment. At the slamming of the door the third man had darted
forward out of the shadows to fling himself upon the wooden barrier,
beating upon it with his fists and cursing like a madman. Judson saw,
understood, and acted, all with the instinctive instantaneousness born
of his trade of engine-driving. The two men in advance were merely
taking the short cut through the mountain to the old workings on the
eastern slope, and the door in the bulkhead, which was doubtless one of
the airlocks in the ventilating system of the mine, had fastened itself
automatically after Flemister had released it.

Judson was a hundred yards down the tunnel, racing like a trained
sprinter for the western exit, before he thought to ask himself why the
third man was playing the madman before the locked door. But that was a
matter negligible to him; his affair was to get out of the mine with the
loss of the fewest possible seconds of time--to win out, to climb the
ridge, and to descend the eastern slope to the old workings before the
two plotters should disappear beyond the hope of rediscovery.

He did his best, flying down the long tunnel reaches with little regard
for the precarious footing, tripping over the cross-ties of the
miniature tramway and colliding with the walls, now and then, between
the widely separated electric bulbs. Far below, in the deeper levels, he
could hear the drumming chatter of the power-drills and the purring of
the compressed air, but the upper gangway was deserted, and it was not
until he was stumbling through the timbered portal that a watchman rose
up out of the shadows to confront and halt him. There was no time to
spare for soft words or skilful evasions. With a savage upper-cut that
caught the watchman on the point of the jaw and sent him crashing among
the picks and shovels of the mine-mouth tool-room, Judson darted out
into the moonlight. But as yet the fierce race was only fairly begun.
Without stopping to look for a path, the ex-engineer flung himself at
the steep hill-side, running, falling, clambering on hands and knees,
bursting by main strength through the tangled thickets of young pines,
and hurling himself blindly over loose-lying bowlders and the trunks of
fallen trees. When, after what seemed like an eternity of lung-bursting
struggles, he came out upon the bare su