aperture thus made.

Bart bounded to the platform with a nimble spring. As his feet clamped
down warningly on the boardway, the man who had pushed up the window
turned sharply.

"It's young Stirling!" Bart heard him mutter. "Drop it, and run."

The speaker sprang to the ground and disappeared around the corner of
the shed with the words.

His companion, who had been stooping on one knee in his prying
operations, essayed to join him, slipped, tilted over, and before he
could recover himself Bart was upon him.

"What are you about here?" demanded the latter.

The prisoner was of man-like build and proportions. He did not speak,
and tried to keep his features hidden from the rays of the near switch
light.

"Lemme go!" he mouthed, with purposely subdued intonation.

"Not till I know who you are--not till I find out what you're up to,"
declared Bart. "Turn around here. I'll stick closer than a brother till
I see that face of yours!"

He swung his captive towards the light, but a broad-peaked cap and the
partial disguise of a crudely blackened face defeated his purpose.