“Talk about cold!” cried Joe, shivering in spite of the fact that he was wrapped in a heavy coat. “I’ll bet the old mercury is down to thirty degrees.”
“Not quite that bad,” laughed Dr. Kirshner, holding up a thermometer. “It’s thirty-eight.”
“Even that is cold for the desert,” said Bob. “I always had the impression that it is hot all the time.”
“There are some places that way,” returned Mr. Lewis. “But certainly not the old Sahara.”
Mr. Lewis and Mr. Holton got out the provisions and began preparing the breakfast.
“And while they’re doing that, suppose we go up to the top of this mound,” suggested Bob to his chum. “It’s rather high. Maybe we can get a view of the country ahead of us.”
“Don’t be gone long, boys,” called Dr. Kirshner, as they made their way to the edge of the hill.
The sand under their feet was, in many places, loose and unstable, but they found sufficient hard spots to make safe footholds. It was not a little difficult to estimate where they could safely climb higher. Perspiration was dripping from them when they at last reached the top and turned their gaze toward the horizon.
A cry of astonishment came from Joe at the scene that was spread out before them. The dunes that stretched away in the distance were tinted with many colors, showing strangely in the early-morning light. Some were pink, others blue, still others green, while the ones farther away paled away into nothingness.
“That’s a new one on me,” remarked Bob, highly puzzled. “I never expected anything like this.”