"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."
"The fellow was pretty sharp to slip by," Ned observed.
"The stockade is no mean barrier, especially with the rows of barbed wire at the top," said Mr. Swift.
"Barbed wire! That's it!" exclaimed Tom. It was just here that Mr. Damon's idea for guarding his prize buff Orpingtons came into play in Tom's scheme of things. "Barbed wire doesn't seem to keep out spies," he added slowly. "But believe me, something else will!"