“Well, I think we’ll fly over the mountain in a straight line west from the rocky defile, in which the disappearance of the cattle seem to have taken place. I have an idea there may be some way of getting under the mountain, by means of a tunnel, perhaps.”
“It would have to be some tunnel,” observed Ned, for they were flying across the flat mountain top now, and could see that it extended for several miles.
“Well, it might be one made by nature. Probably is, if there’s one in existence,” Jerry said.
On and on they flew, now circling to the right, and again to the left in an endeavor to cover as much ground as possible. But they saw nothing that would lead to a solution of the mystery.
All that day was spent in flying about, peering here and there through the powerful glasses, the airship moving along at a low elevation so the boys might make more careful observations.
“Well, we don’t seem to have done much the first day,” observed Bob, as they descended to a level, sandy plain as night settled down. “All we can do is to get something to eat and go to bed.”
“There’s another day to-morrow,” remarked Ned, “so don’t eat up everything to-night.”
“No danger!” exclaimed Jerry. “Chunky brought along enough for a small army.”
“Well, I’m as hungry as half an army myself!” laughed the stout lad.
“Going to stand guard to-night?” Ned asked, as they proceeded to make the cabin of the earth-fast airship snug and comfortable.