It was evident that the fire had leaped the intervening shoulder of the spur in one of the unaccountable, but by no means rare, phenomena of this kind of disaster.

The circling heights around were yet untouched; only the hollow, and the ledge of rock against which they had blundered with their horses when they were seeking the mysterious window in last evening's darkness, were calcined and destroyed.

He dismounted and climbed the ledge, still warm from the spent fire.

A large mass of grayish outcrop had evidently been the focus of the furnace blast of heat which must have raged for hours in this spot.

He was skirting its crumbling debris when he started suddenly at a discovery which made everything else fade into utter insignificance.