Holes of that shape are common in the black volcanic cliffs of the Pajarito Plateau, where they occur in great numbers. This one was solitary, dark, and seemed to lead into another cavern. Though it lay higher than Jacinto's head, it was not beyond easy reach of his arms, and to the Bishop's astonishment he began deftly and noiselessly to place the stones he had collected within the mouth of this orifice, fitting them together until he had entirely closed it. He then cut wedges from the piñon faggots and inserted them into the cracks between the stones. Finally, he took a handful of the earth that had been used to smother the dead fire, and mixed it with the wet snow that had blown in between the stone lips. With this thick mud he plastered over his masonry, and smoothed it with his palm. The whole operation did not take a quarter of an hour. Without comment or explanation he then proceeded to build a fire. The odour so disagreeable to the Bishop soon vanished before the fragrance of the burning logs. The heat seemed to purify the rank air at the same time that it took away the deathly chill, but the dizzy noise in Father Latour's head persisted. At first he thought it was a vertigo, a roaring in his ears brought on by cold and changes in his circulation. But as he grew warm and relaxed, he perceived an extraordinary vibration in this cavern; it hummed like a hive of bees, like a heavy roll of distant drums. After a time he asked Jacinto whether he, too, noticed this. The slim Indian boy smiled for the first time since they had entered the cave. He took up a faggot for a torch, and beckoned the Padre to follow him along a tunnel which ran back into the mountain, where the roof grew much lower, almost within reach of the hand. There Jacinto knelt down over a fissure in the stone floor, like a crack in china, which was plastered up with clay. Digging some of this out with his hunting knife, he put his ear on the opening, listened a few seconds, and motioned the Bishop to do likewise. Father Latour lay with his ear to this crack for a long while, despite the cold that arose from it. He told himself he was listening to one of the oldest voices of the earth. What he heard was the sound of a great underground river, flowing through a resounding cavern. The water was far, far below, perhaps as deep as the foot of the mountain, a flood moving in utter blackness under ribs of antediluvian rock. It was not a rushing noise, but the sound of a great flood moving with majesty and power. "It is terrible," he said at last, as he rose. "_Si, Padre_." Jacinto began spitting on the clay he had gouged out of the seam, and plastered it up again.