“By all means.”
In a few moments more Frank and Randall were aboard the Scorcher.
They said nothing to the others of the subject uppermost in their minds. But Frank started the machine at once back up the valley.
Scarcely twenty miles had been made, however, when a strange, grayish bank of clouds began to rise upward toward the zenith.
Thus far our adventurers had not experienced a storm of any violence. There had been only some slight rains.
But the moment Frank saw the strangely tinted clouds he became alarmed.
“On my word, Randall,” he said, “I believe we are going to have a rough storm.”
The geologist’s face was grave. He studied the sky a moment. Then he swept the landscape.
“Which is the highest point of land near here?” he asked.
“I think it is yonder hill,” said Frank, pointing to an elevation about five miles distant.