“It must be some sort of volcano,” Roger continued, thoughtfully. “It has no visible cone, like most of them do, and so the heat escapes in this way through hundreds of little vents.”
That is about the nearest explanation any scientist has ever been able to give why this one region in all the world contains innumerable geysers, hot springs, boiling colored mud pots, and various other wonders of Nature. ([Note 5].)
“All I can say is that I don’t blame any poor Injun for believing the place is Evil Ground,” muttered Mayhew, as he stared at the strange spectacle of that blue and yellow and green mud boiling ceaselessly, and throwing off steam that had a peculiar odor, unlike anything they had ever smelled before.
He looked around him, and shrugged his shoulders. So many remarkable things were to be seen, such as a frontiersman might well view with alarm, that it was no wonder Mayhew felt uneasy. Left to his own devices he would have turned his back on this enchanted region, and considered himself a lucky man if only he might get away with his life.
“It strikes me,” Dick observed, “that we need not hope to find Williams anywhere about here, if, as we fear, he has been taken prisoner by those Blackfoot Indians.”
“No, because they would never come to a place like this, unless their old medicine man was along to make a palaver with the Evil Spirit,” Roger suggested. “That is what I heard a Mandan brave say, and I guess it must be about so. We will have to go further, and look for Jasper elsewhere.”
Mayhew seized upon this hint to make a start, and, noticing how anxious the scout seemed to be to shut out the strange spectacle of that ever boiling pool of gayly tinted mud, the boys followed at his heels.
“I can hear other spouting fountains not far away!” declared Roger. “Sometimes it is like a giant snake hissing, and then again I seem to catch a distant but terrible roaring sound, reminding me of that fierce bear in the cave.”
“Even if the winter is coming on here, there are plenty of birds still to be met with,” Dick remarked, as a flock of cawing crows started up from a tree-top near by, and flew away.
“Yes, there are hawks also, and I am sure I saw a pair of great bald-headed eagles soaring away up in the sky, wheeling in circles as they rose. Besides, we have stirred up many of those brush fowl that are so much like our chickens at home, and make such fine eating.”