“Here’s hoping good and hard that it will widen out for you one of these fine mornings,” Dick said; and then the old man took the candle and led the way back up the incline.
It was in the cavern-like place where the vein had been lost that Dick asked his guide to wait a minute and let him look around. The break in the continuity of the vein of argentite was evidently caused by what is technically known as a “fault,” a crack in the earth’s crust made by some volcanic upheaval. In many such cracks one side or the other has slipped up or down or sidewise, and there had apparently been some such a slip here.
“You had lots of courage to go on digging when you struck this ‘fault,’” said Dick. “We struck one in our mine in the Timanyoni, and it was forty feet thick.”
“Uh-huh,” said the old man; “a lime-horse. That’s what this was.”
Dick stooped down and picked up a bit of the broken rock stuff with which the crack had been filled in some later convulsion than that which had opened the gash in the earth’s crust.
“Doesn’t look quite like a lime-horse,” he commented, examining the fragment by the light of the candle. “Seems too heavy for any of the calcareous rocks. Ever have it assayed?”
The old man shook his head. “Naw; it ain’t nothin’ but rock—fault-fillin’.”
Dick put the bit of stuff in his pocket, meaning to look at it again by the better light of the cabin lamp. And with that the matter rested, for the time being.
When they were back in the cabin the patriarch lighted his corn-cob pipe and wanted to hear more about the “queer” metals the three young prospectors were going to look for. Dick did his best by way of explaining, telling of the uses of some of the metals—tungsten in electric lamps, vanadium as an alloy for steel, carnotite as the source of the wonder-working radium.
The old man chuckled.