"They know we shall await them in this hall."
After these few words each fell back into his thoughts. The silence was only troubled by the mysterious sounds of the grotto, which re-echoed nearly at equal intervals with an horrific din. A long period elapsed. All at once, ere any sensible noise had warned Don Miguel, Valentine raised his head with a hurried movement.
"Here they are," he said.
"You are mistaken, my friend," Don Miguel observed; "I heard nothing."
The hunter smiled.
"If you had spent," he said, "like we have, ten years in the desert, interrogating the mysterious voices of the night, your ear would be habituated to the vague rumours and sighs of nature which have no meaning to you at this moment, but which have all a significance for me, and, so to speak, a voice every note of which I understand, and you would not say I was mistaken. Ask the chief: you will hear his answer."
"Two men are climbing the hill at this moment," Curumilla answered sententiously. "They are an Indian and a white man."
"How can you recognise the distinction?"
"Very easily," Valentine responded with a smile. "The Indian wears moccasins, which touch the ground without producing any other sound than a species of friction: the step is sure and unhesitating, as taken by a man accustomed to walk in the desert, and only put down his foot firmly: the white man wears high-heeled boots, which at each step produce a distinct and loud sound; the spurs fastened to his boots give out a continuous metallic clink; the step is awkward and timid; at each moment a stone or crumble of earth rolls away under the foot, which is only put down hesitatingly. It is easy to see that the man thus walking is accustomed to a horse, and does not know the use of his feet. Stay! They are now entering the grotto: you will soon hear the signal."
At this moment the bark of the coyote was raised thrice at equal intervals. Valentine answered by a similar cry.