nically, and turned back to his work. "No; you
can't fasten it on Smith," he said shortly. "It was after he went out
that I returned the box to the safe. But, if it's any good to you--he was
in here from about five-thirty to ten minutes to six, and was talking
with one of the boys in the outer office when I left."

"And Mr. Black, were you outside during the time Smith was in here?"

"No, I--Yes, I was, too. About a quarter to six I was over at the
speaking-tube for a minute.

"But enough of this nonsense," the manager added sharply. "The box was in
the safe when I closed it. Don't bother me any further with your pretense
of investigating. I don't believe it is sincere."

Despite this cutting declaration Jack turned away with secret
satisfaction.

Just outside the office door he made a second discovery--a small one, but
one which further strengthened the theory he had formed.

It was a small coal cinder and an ash stain in the shape of a heel,
apparently overlooked by a careless sweeper.

They could only have been left by a foot which came from the cellar!

Promptly Jack turned toward the cellar door, and made his way down into
the big basement.

Going directly to one of the rear windows, he carefully examined it. The
cobwebs and the dust on the sill had not been disturbed for months.

He turned to the second, and instantly emitted a shrill whistle of
delight. Its cobwebs had been torn and swept aside, and the ledge brushed
almost clean. And evidently but a short time before, for the cleared
space showed little of the dust which constantly filtered through the
floor above.

"Fine!" exclaimed Jack. "Now I--" He paused. The window was securely
latched on the inside!

For several minutes Jack stood, disappointed and mystified. Then,
examining the latch closely, he laughed, and grasping it with his
fingers, easily pulled it out. It had been forced from the outside, and
merely pressed back into the hole.

But its being replaced showed that the intruder had not made his escape
that way.

Jack began an examination of the end of the cellar under the express
office. And the exit was soon disclosed.

The dividing wall was of boarding, and at the outer end, to facilitate
the examination of the gas metres of the two companies, was a narrow
door. Ordinarily this door was secured on the telegraph company's side by
a strong bolt.

The bolt was drawn, and the door swung easily to Jack's touch!

On the farther side