"I wonder what Professor Wright is doing?" said Nort.
"Oh, digging up a lot of old bones, I reckon," Bud answered. "But let's get grub and rest. I'm tired."
The events of the past few days had been strenuous enough to make them all welcome a period of rest. And they had it, for a few hours. And then something occurred to start a series of happenings that lasted and created excitement for some time.
It was toward the middle of the afternoon when Nort, who had gone down the stream a little way, looked across Spur Creek and saw hanging in the hazy air a cloud of dust.
"Wonder if that's a wind storm," he mused. But as there was not a sign of vapor in the clear blue sky he gave up that theory. "Guess I'd better let 'em know," he thought, turning back toward the fort.
And when the others came out to look at the cloud of dust, on the Mexican side of the river—a cloud which had grown larger—Bud exclaimed:
"Sheep, I'll bet a hat!"