quantity of the suspected stuff out in the yard back of the station
house, and had exploded it.

At a moment when the office was empty of patrons Mr. Drowan stepped
into the cupboard for a moment, as though searching for something.

"How late do you stay open?" whispered Hemingway.

"Ten o'clock, usually, on Saturday nights, but we'll keep open
as late as you want, officer."

"Better keep open until midnight, then."

So they did, Dick telephoning his parents at the store to explain
that he was at the express office helping Dave.

Midnight came and went. A few minutes after the new day had begun
Hemingway came out of the cupboard.

"You may as well close up, Drowan," the plain clothes man decided.
"The fellow who calls himself Tripps isn't going to show up.
If he had been going to claim his box he'd have been here before
this."

"You think he got scared away?" asked the night manager.

"The fellow was probably keeping watch on this office. He saw
what happened, and decided not to run his neck into a noose.
You'll never have any word from Tripps."

"Isn't it just barely possible," hinted one of the clerks, "that
the man wanted the stuff for some legitimate purpose?"

"A man who knows how to use nitroglycerine," retorted Hemingway,
gruffly, "also knows that it's against the law to ship nitroglycerine
unlabeled. He also knows that it's against the law for an express
company to transport the stuff on a car that is part of a passenger
train. So this fellow who calls himself Tripps is a crook. We
haven't caught him, but we've stopped him from using his 'soup'
the way he had intended to use it."

"Wonder what he did want to do with it?" mused Dick Prescott.

"There are any one of twenty ways in which the fellow might have
used the stuff criminally," replied the plain clothes man. "Of
course, for one thing, it could be used to blow open a safe with.
But safecracking, nowadays, is done by ordinary robbers, and
they're able to carry in a pocket or a satchel the small quantity
of 'soup' that it takes to blow the lock of a safe door, or the
door off the safe."

After thinking a few minutes, Hemingway went to the telephone,
calling up the chief of police at the latter's home. The plain
clothes man stated the case, and suggested that the story be told
to "The Blade" editor for publication in the morning issue. Then,
if anyone in town had any definite suspicion why so much nitroglycerine
should be needed in