“Now,” continued Rob, “none of us has as yet set eyes on any mine. We only believe one has been planted under the trestle here. It would be the right thing for us to follow up this broken wire and see for ourselves how true this theory is. Shall we start, sir?”
“Without a second’s delay!” snapped the aroused lieutenant. “There may yet be sufficient time to pursue the rascals and bring them to justice for this attempted outrage. And believe me, boy, we will make them pay dearly for their fun, if only we can lay hands on the cowardly curs!”
Still holding the lantern, and followed by the group, Rob was already tracing the course of the pinned-down copper wire. As he had the conductor’s light, of course that worthy had to keep trotting at his heels, which was sufficient excuse for further delay on his part.
They speedily came to the high trestle, and passed under the heavy beams and timbers of which it was constructed. Then there were exclamations that ran the whole gamut of wonder and horror, when the end of the wire showed them a small box that contained enough explosives to wreck the entire structure, for it had been artfully placed so as to do the utmost damage possible.
“Lift up that box and handle it carefully, two of you men,” ordered the officer. “Soak it in the river, and stand guard over it until relieved. We will want it as evidence when handing in a report of this mad adventure.”
Hardly waiting to see that they started to carry out his instructions, he turned once more upon Rob. Now there was only admiration in the officer’s manner of speaking to the boy.
“We apparently owe a great deal to the efficiency of you and your brave scout comrades, my lad,” said the now convinced lieutenant. “Perhaps you could add still further to the debt by showing us where those scoundrels were in hiding, waiting to fire the mine. I confess an overpowering desire to follow them, and save them the trouble of recrossing the boundary line.”
“Nothing easier, sir,” calmly replied Rob. “All we have to do is to follow the other half of the broken wire and it will lead us to their nest.”
“Well, I should say so!” chuckled Andy, wondering why the officer had not hit upon this very simple method instantly; but then, Andy reflected, the poor fellow had in his youth never had the chance of becoming a scout and learning the art of using his wits to look for the cause of things, as well as cultivating the habit of observation.
Back they hurried in an eager bunch to the spot where Rob had severed the connecting link with his little combination pliers and wire-cutter. Here the other line was taken up. It led them toward the identical spot where the boys had previously decided the plotting invaders were hidden. This proved to be a clump of dense bushes, affording an excellent refuge secure from discovery, although it was near enough to the railway embankment to allow observation.