"I, too, am sorry," began Roldan. "But what is the matter?"
The great masses of cattle had begun to heave suddenly. They were uttering hoarse growls of terror. The mustangs of the vaqueros stood suddenly still, quivering. Then, abruptly, a horrible stillness fell. All things breathing seemed to petrify. But only for numbered seconds. From beneath came a low roar, gathering in volume like the progression of a tidal wave; then the world heaved and rocked.
"Temblor! temblor!" went up as from one mighty horrified throat. The priest shouted to the boys: "Stay where you are;" to Don Tiburcio and his guests: "With all your speed after me."
They understood his meaning. The cattle were leaping over one another, bellowing madly, giving no heed to the hoarse cries of the terrified vaqueros. In a moment a blaze of colour was flying down the valley, a long brown arm lifted high above it. In twenty seconds five thousand tossing horns and blazing eyes and heaving flanks were in pursuit.
The vaqueros did their best, although their faces were white and their lips shaking. Three that were between the uniting herds, had their legs crushed into their mustangs' sides, and were borne along and aloft, shrieking horribly, adding to the fury of the stampede. Another, trying to head the cattle off, rode into a sudden split in the hard adobe soil and went down beneath those iron feet.
The boys clung together. The wall was broad, but it rocked continuously, whether from other shocks or from the hoof-assaulted earth it would have been impossible to say. A curving outer flank of the flying mass bulged against it, and it quivered horribly with the impact. The boys strained their eyes after the retreating points of colour. Would they escape? Were the frightened mustangs fleeter of foot than those maddened brutes? And if they were—the Casa!
"I think," said Roldan, "that we had better get down on the other side. This wall may go down any minute; and the cattle are all looking in one direction."
"You are right," said Rafael. "This way—Ay de mi!"
There was another heave of the earth, distinct from the steady vibration of stampeding cattle. The adobe wall rocked violently, sprang, twisted, crumbled to the ground, a heap of dust.
For a moment the boys were invisible. Then they emerged, one by one, choking and spitting, rubbing their eyes with their knuckles. When they had recovered some measure of vision they huddled together, staring with affrighted eyes at the moving wall of cattle not twenty yards to their left, hardly able to keep their balance.