Consequently it must have been at that spot that Miriam and the Indian found him.

He had, too, a vague impression of seeing Miriam coming out of the cave, dragging the chest; and there, sure enough, was a metal box, strapped to the saddle of the pack-mule.

But the mystery remained very dense.

And although the reader is in a position to analyze events more closely than the actors themselves could do, it may be doubted whether the essential mystery is much clearer to him than it was to them.
"We know that the ancient Aztecan priests were adepts in magic," observed the professor, "and it's natural that some of their learning should have descended to their posterity.

We have been clever in giving names to such phenomena, but we know perhaps even less about their esoteric meaning than the Aztecans did.