Now, the three members of the old Eagle Patrol had been together so much, and passed through so many adventures in common, that long since they had agreed on a system of signals whereby they could communicate without any outsider being aware of what was going on. Thus a faint twitter, resembling a sleepy bird protesting at being pushed on its perch, would indicate that something had been seen that ought to be taken into consideration. A low grunt, after the manner of a hedgehog hunting for succulent roots, meant that retreat would be in order, though to be undertaken with the utmost circumspection.
There were a number of other ways in which the scouts could communicate without anyone being the wiser. Rob’s warning indicated that he had made a discovery, which they, too, would be able to hit upon if they used their ears to the best advantage.
Ah! now it came stealing up to them. Even Tubby knew that it was not the grumble of a burrowing animal, but the low mutter of a hoarse, excited voice. It came but faintly at best, and certainly would never reach the hearing of any one located several times as far away as the crouching boys and Zeb were at the time.
Accustomed to practicing such things as the scouts were, they had no difficulty at all in picking out the exact spot from which this hoarse whisper came. Even Tubby could do that, for he was far from a tenderfoot, having been in harness quite as long as his two mates.
This tell-tale whisper informed them where the men whom they had set out to balk, were hiding. Yes, it was far enough away from the railway embankment to allow them to escape any possible evil results when the climax arrived and the mine was sprung, and yet sufficiently close to let them see the train as it swung down upon the high trestle, perhaps slowing up for the passage of the bridge.
Rob made a mental calculation as quick as a flash. He was thus enabled to get his bearings, and could figure out just about how that wire was likely to run. Thus it was possible, by making a little half-circuit, for them to cut across the line midway between the two ends, or perhaps still closer to the trestle. This would increase their own peril in case events moved more swiftly than they had been calculating.
Even more than at any previous time the utmost secrecy was necessary. Tubby felt that he was placed on his mettle. A stumble now would excite suspicion, and that, in turn, might influence the wary schemers, fearful of being caught. Rather than have their evil plans balked they would naturally prefer to explode the mine even before the train arrived.
Rob may have considered Tubby’s customary clumsiness, and made provision to take as little chance as possible. That would be the natural conclusion to be drawn from the fact that he now sank still lower, until on his hands and knees, and in this ungainly but practical position they were all creeping along.
Tubby heard that low grumble of a fretful, impatient voice no longer. Perhaps the incautious member of the invading party had been suppressed by a fierce shove. Tubby wondered if their presence in the vicinity could have been discovered, or even suspected. He was preparing his nerves against a sudden terrific roar, as the valuable railway property came crashing down. He also fervently hoped that none of the heavy timbers would carry over to where they were creeping along.
Tubby was not feeling over-happy, but nothing would have induced the boy to forego the excitement. Perhaps, his nature being slow, Tubby might hold back longer than such impetuous fellows as Andy and some of the other Eagles. Once he enlisted in an undertaking he could not be easily “frozen out.”