The rock on the plateau reared its misshapen head to the heavens at a height of something over two hundred feet, and its great base formed a vast cavern out of which, fanwise, spread a lake of steaming water, which flowed on to the very brink of the hill where it overshadowed the creek below. Thus it was, more than half the lake was held suspended in mid-air, with no other support than the parent hill from which its bed projected. It was an awesome freak of nature, calculated to astonish even eyes that were accustomed to the sight of it.
But Buck was not thinking of these things now. He was looking at the view. He was looking at the sky. He was looking from this great height for an explanation of the curious, ruddy light in the sunless sky, the teeming haze which weighted down the brain, and, with the slightest movement, opened the pores of the skin and set the perspiration streaming.
In all his years of the Montana hills he had never experienced such a curious atmospheric condition. Less than an hour ago he had left the Padre at the fur fort under a blazing summer sky, with the crisp mountain air whipping in his nostrils. Then, quite of a sudden, had come this change. There were no storm-clouds, and yet storm was in every breath of the superheated air he took. There was no wind, nor anything definite to alarm except this sudden blind heat and the purple hue which seemed to have spread itself over the whole world. Thus it was, as he neared the mysterious mountain, he had made up his mind to its ascent in the hope of finding, there upon the unwholesome plateau, the key to the atmospheric mystery.
But none seemed to be forthcoming, so, turning at last to the patient Cæsar, he once more returned to the saddle and rode on to the barren shores of Devil's Lake.
The lake was a desolate spot. The waters stretched out before him, still, and silent, and black. There was not even a ripple upon its steaming surface. Here the haze hung as it always hung, and the cavern was belching forth deep mists, like the breathing of some prehistoric monster. He glanced up at the birdless rock above, and into the broken outlines of it he read the distorted features of some baleful, living creature, or some savage idol. But there was no answer here to the questions of his mind, any more than there had been on the rest of the plateau, so he rode on along the edge of the water.