is about nine miles in circumference. We can't search every foot of such a large territory as that."
"We haven't got to search every foot of it," went on Oliver, who was highly enthusiastic on the subject and was trying his best to make Dan and myself equally so. "You know, Dan, and so does Mark, that all we've got to do is to locate the double-headed idol carved out of lava, standing at the entrance to the cave. That ought not to be so difficult, even in a territory ten or twelve miles in extent."
"You must remember one thing, Oliver," I returned. "You have both sailed the Pacific, while I have never been west before. Yet I have read enough about the Sandwich Islands, as they used to be called, to know that the gigantic volcano Kalauea is in a constant state of eruption, overflowing its basin at various points and sending its liquid lava flowing in hundreds of directions. If this Cave of Pearls, as the Kanakas called it, existed fifty years ago, it is more than likely that the lava filled it up long since, and the pearls may be a hundred feet underground—or under lava, to speak more correctly."
"Then you don't advise undertaking the expedition, Mark?" said Oliver disappointedly.
"I didn't say that. Our time is our own, we each have quite some money to spend, and a trip