second, and down the steps went Chester, three at a bound, tip-toeing it
in pursuit. Ten seconds brought him close to the culprit,--a tall,
slender shadow.

"You villain! Halt!"

Down went the ladder on the dusty road. The hand that Chester had
clinched upon the broad shoulder was hurled aside. There was a sudden
whirl, a lightning blow that took the captain full in the chest and
staggered him back upon the treacherous and entangling rungs, and, ere
he could recover himself, the noiseless stranger had fairly whizzed into
space and vanished in the darkness up the road. Chester sprang in
pursuit. He heard the startled challenge of the sentry, and then Leary's
excited "Halt, I say! Halt!" and then he shouted,--

"Fire on him, Leary! Bring him down!"

Bang went the ready rifle with sharp, sullen roar that woke the echoes
across the valley. Bang again, as Leary sent a second shot after the
first. Then, as the captain came panting to the spot, they followed up
the road. No sign of the runner. Attracted by the shots, the sergeant of
the guard and one or two men, lantern-bearing, came running to the
scene. Excitedly they searched up and down the road in mingled hope and
dread of finding the body of the marauder, or some clue or trace.
Nothing! Whoever he was, the fleet runner had vanished and made good his
escape.

"Who could it have been, sir?" asked the sergeant of the officer of the
day. "Surely none of the men ever come round this way."