“And now the question is this,” Frank went on, “what was the door fitted for? Why did the men who found the cave desire privacy? Is there gold in there? Have the men who have been setting fire to the forests established a home here? Is this the hiding place of a band of outlaws? You see there are lots of questions to ask about the two caverns,” Frank added, with an uneasy laugh.
Ned closed the stone door and turned on both electric flashlights, making the place light as day where they stood. The inner cavern was as bare as the outer one save for dead leaves and grass which lay in heaps on the stone floor, and for half a dozen rough benches which were piled in one corner. At the farther end hung a gaudy curtain, once handsome, but now sadly spotted with mildew because of dampness.
“Here’s the inner chamber,” laughed Frank, drawing the curtain aside. “And it looks like it was the private office of the bunch, too,” he added, as he turned the light about the walls.
There was a desk in the third cavern, a swivel chair, a small case of books, and a rusty safe, which looked as though it had not been opened for years. A current of fresh air came from the rear, and a small opening was soon discovered.
“That doubtless leads to some cañon not far away,” Ned said. “Makes a pretty decent place of it, eh?”
“Good enough for any person to hide in,” replied Frank. “Now,” he added, “tell me what you think of it. Who cut this cavern, and who brought the furniture here? I’ll admit that my thinker is not working.”
“Nature made the caverns,” Ned replied. “There is what geologists call a fault in the rock here. Owing to volcanic action, doubtless, the strata shifted, probably thousands of years ago, and when the seam appeared the broken pieces fell apart. These chambers show the width of the seam. There undoubtedly was a great earthquake at the time, and the lake below might have been dredged out at that time.”
“Of course,” Frank said, “I might have known that! Now, here’s another question: How far does this seam extend under the Rocky Mountains? If it passes beyond these three chambers, why not make a fourth room for ourselves so as to be on the spot when the men who make headquarters of the place come back?”
“That may be a good thing to do,” Ned admitted, “but, still, I would not like to be the one to lie in wait here. Suppose we try to learn something of the character of the people who come here? They seem to sleep on dry leaves and eat off benches. Rather tough bunch, I take it. Perhaps we have struck Uncle Sam’s enemies the first thing!”
Keeping their lights on, and working as silently as possible, always with an eye to the outer cavern, the boys made a careful search of the inner chamber. The desk was not fastened, and a cupboard afterward discovered in a niche was open also. There were dishes in the cupboard and writing materials in the desk.