ernal machine in that package
we may be sure that we are dealing with desperate men. We've got to
keep our eyes open."

"Wide open," added Ned.

"I'll say we have," said Tom.

Chapter XII

The Try-Out Day Arrives

It did not need Ned Newton's story of what he had overheard at the bank
to prove that an attempt had been made to blow to pieces Tom Swift's
electric locomotive before even it had been tested.

An examination of the water-soaked package in the open yard of the
shops of the Swift Construction Company, proved that there was enough
explosive in the bomb to blow the shed itself to pieces. But the
stopping of the clockwork attachment of course made the bomb harmless.

"The main thing to be explained," Tom said, when he and his father and
Ned discussed the particulars of the affair, "is not who did it, or
what it was done for. Those are comparatively easy questions to answer."

"Yes," agreed Ned. "O'Malley did it, or caused it to be done; and it
was an attempt to balk Mr. Bartholomew and the H, & P. A. rather than
a direct attack upon the Swift Construction Company."

"I am afraid, however," remarked Mr. Swift, "that Tom has aroused the
personal antagonism of this spy from the West. We must not overlook
that."

"I don't," replied the young inventor. "O'Malley has it in for me. No
doubt of that. But he could not be sure that I would be hurt by the
explosion he arranged for."

"True," said his father.

"The attempt was against my invention. And O'Malley was doubtless urged
to destroy the locomotive that I am building because my success will
aid Mr. Bartholomew and his railroad."

"Quite agreed," said Ned. "But--"

"But the important question," interrupted Tom, "is this: How did the
bomb get into the interior of the electric locomotive? That is the
first and most important problem. Its having been done once warns us
that it can be done again until our system of guarding the works is
changed."

"We have five watchmen on the job at night, and the gates are never
opened in the daytime to anybody for any purpose without a pass,"
declared Ned. "I don't see how that fellow got in here with the time
bomb."

"Exactly. It shows that there is a fault in our system somewhere," said
Tom grimly. "We cannot surround the place at night with an armed guard.
It would cost too much. Even Koku cannot be everywhere. And I have
reason to know that he was wandering about the stockade last night as
usual."