Dick had sustained that same curiosity, so together they made their way to the beginning of the previous day’s disaster. They chilled when they saw how effectually they had been caught; for the bowlder completely filled the entrance to the shaft and would have proved a hopeless trap had they tried to escape by burrowing around its edge. It rested, as they had discovered, on solid rock, and its course down the hillside was clearly marked.

“What gets me,” said the veteran miner, “is what could have started it. I noticed it up there when we went in. It was sort of poised on 74 that little ledge you see, and it didn’t have to roll more than thirty feet.”

He began to climb up the bowlder’s well-defined path, and suddenly called to his partner with a hoarse shout, needlessly loud.

“Come up here,” he said. “That bowlder never started itself! Some one helped it. What do you think of that?”

Dick hastily climbed up to his side and looked. The rock around was bare of growth or covering, so that no footprints could be discerned; but a rock rested there that had plainly been used as a fulcrum. The surface beneath it was weather beaten and devoid of moisture, which indicated that it had lain there but a short time, probably only from the time of its mission on the preceding day. They found themselves standing up and staring around at the surrounding hills as if seeking sight of the man who had attempted to murder them.

“We’ll find out about this!” Bill exclaimed. “Good thing we know enough to look.”

He limped to the edge of the barren spot and began to circle around its edge, while Dick did likewise, following his example. They found a footprint at last and took the trail. It did not lead them far before they came to a path on top 75 of the hill that was so well used that any attempt to follow it was useless; but, intent on seeing where it led, they walked along it as it led straight away toward the timber. Scarcely inside the cool shadows of the tamaracks they paused and looked at each other understandingly; for thrown carelessly into a clump of laurel was a long, freshly cut sapling, that had been used as a lever. They recovered it from its resting place and inspected it. There was no doubt whatever that it had been the instrument of motion. Its scarred end, its length, and all, told that the man who had used it had carried it this far to discard it, believing his murderous work done.

“I noticed that rock, as I said before,” declared Bill. “You noticed how round it was on one side? Well, a man could take this lever, and by teetering on it until he got it in motion, finally upset it. The chances were a hundred to one it would land in the mouth of the shaft. And it’s a cinch, it seems to me, he wouldn’t do that for fun.”

Dick shook his head gravely.

“But who could it be?” he insisted. “Who is there that could want us out of the way badly enough to murder us? No one here knows or cares a continental about us! It seems incredible. 76 It must have been sheer carelessness of some restless loafer who wanted to see the rock roll.”