"Yes, I have been observing them all day. To tell the truth I was rather doubtful about the wisdom of taking a number of boys across the desert. It's bad enough for men well hardened to the work."
"I trust your apprehension no longer exists," smiled the Professor.
"Not a trace of it left," replied Parry, with a hearty laugh. "Young Brown handled that bucking pony splendidly this afternoon. He's a good horseman for a boy."
"Master Tad is a better one. You'll agree with me if you get an opportunity to see him in any work that's worth while."
"Well, good night, boys," called the Professor, as he saw the lads moving toward their tents.
"Good night, Professor, sleep tight," they shouted merrily altogether. "Good night, Mr. Parry. We'll be up with the birds."
"Birds," sniffed Stacy. "A tough old hen couldn't live out on this desert."
In a short time the camp settled down to sleep. The guide, with a last look about and a long, comprehensive study of the sky, sought his own tent, where in a few moments he, too, was sound asleep.
After a time the moon came up, in the light of which the weather-beaten tents of the Pony Rider Boys were mere specks on the vast expanse of desert.
Not a sound disturbed the quiet scene. However, had any of the occupants of the little tents been awake, they might have observed a thin, fog-like film drifting across the sky from the southwest. On and on it came until finally it had blanketed the moon, casting a veil over the landscape.