"Not so fast, my boy," admonished Pete. "Might as well say that every feller who finds a Canadian dime in his pocket is a Kanuck. Say," he suggested suddenly, "suppose you boys jes' see if you can find any tracks around the base of the mesa."
They scattered and looked carefully about them, but the bunch-grass grew in quite a broad belt all about, and no footmarks could be discerned. Nor did a careful examination of the grass show any broken or trampled blades, as would have been the case had ponies been there recently.
"That decides it," announced Pete, after this last fact had been ascertained, "whoever made those foot-marks wasn't here recent, that's a fact. But who could they have been, and what brought them here?"
"Maybe Indians," suggested Ralph sagely.
"Yep, if Indians wore boots, which they don't," grinned Pete, while poor Ralph colored to the roots of his hair over the general laugh that arose at his expense.
"I think," announced the professor finally, "that it would be our best plan to go ahead exploring the mesa. After all, there is nothing here that can hurt us. Those ruffians of Black Ramon's have been driven out of the country, and, anyway, they would not be likely to come here. As for Indians, their reservation is many miles to the north-east. Whoever was here, was either on a scientific quest, like ourselves, or else unfortunately lost in the desert."
"Jes' ther same," grunted Pete, in a low voice that nobody overheard, "I'd like ter know what all this means: Big, shadowy shapes flitting around in ther night, and footsteps here in ther mornin'. It don't look right."
He took a swift glance all about him. In every direction lay the desert—glittering, far-reaching, lonely as the open sea. The only break in the monotony came to the south—on the border—where stretched the rocky, desolate ridge.
"No one wouldn't come here without an object," reasoned Pete to himself, as they began the ascent of the narrow, tortuous trail, "now, what in thunder could that objec' hev bin?"