"A mountain storm coming up," answered the boy, who for some time had lain wide awake listening to the ever increasing roar. "Go to sleep."
Yet, instead of following his own advice, Tad lay with wide-open eyes awaiting the moment when the storm should descend upon their camp in full force.
He had not long to wait.
With a crash and a roar, as if the batteries of an army had been suddenly let loose upon them, the elements opened their bombardment directly over the camp.
"Ugh!" exclaimed Chunky in a muffled voice, as he crawled further down under the blanket to shut out the glare of the lightning.
For a few moments the boys lay thus. Then Tad, rising, slipped to the opening of the tent and looked out wonderingly upon the impressive scene. Each flash appeared to light up the mountains for miles around, their crests lying dark and forbidding, piled tier upon tier, the blue, menacing flashes hovering about them momentarily, then fading away in the impenetrable darkness.
The camp appeared to be wrapped in sleep, and, by the bright flashes, Tad observed that the burros of the pack train were stretched out sound asleep, while, off in the bushes, he could hear the restless moving about of the ponies, their slumbers already disturbed by the coming of the storm.
The Pony Riders had been out three days from Pueblo, to which point they had journeyed by train, the stock having been shipped there in a stable car attached to the same train. In the city of Pueblo they found that all preparations for the journey had been made by Lige Thomas, the mountain guide whom Mr. Perkins had engaged to accompany them.
Besides the four ponies of the boys there were the Professor's cob, Thomas's pony and a pack train consisting of six burros, the latter in charge of Jose, a half-breed Mexican, who was to cook for the party during their stay in the mountains.
It was a brave and joyous band that had set out from the Colorado city in khaki trousers, blue shirts and broad-brimmed sombreros for an outing over the wildest of the Rocky Mountain ranges.