a storm of stones.

fortunately for the fugitives, the cavity into which they had crept was a shaft of but slight diameter, otherwise they could not have gone down without dropping far enough to cause death, for the echoes from the pebbles betokened a vast vertical depth.

as it was, the void turned out to be somewhat like that of a stone-built chimney with here and there a point left projecting. it was so narrow, moreover, that they were able to use both hands and knees in the descent, and by this means they accomplished it.

they went but slowly, and took care to proceed with caution. they knew that a false step, the slipping of a foot or finger, or the breaking of a fragment that gave hold to their hands, would precipitate them to an unknown depth.

they did not go farther than was necessary for quick concealment. there was noise made in their descent, and they knew that the indians would soon be above, and might hear them. their only hope lay in their pursuers believing them to have gone by the left hand path to the plain above. in time the indians would surely explore both branches of the ravine, and if the cunning savages should suspect their presence in the shaft there would be no hope for them. these thoughts decided them to come to a stop as soon as they could find foothold.

about thirty feet from the top they found this, on a point of rock or ledge that jutted horizontally. it was broad enough to give both standing room, and as they were now in the midst of amorphous darkness, they took stand upon it.

the indians might at any moment arrive on the platform above. they felt confident they could not be seen, but they might be heard. the slightest sound borne upwards to the ears of the savages might betray them, and, knowing this, they stood still, scarce exchanging a whisper, and almost afraid to breathe.

it was not long before they saw that which justified their caution—the plumed head of a savage, with his neck craned over the edge of the aperture, outlined conspicuously against the blue sky above. and soon half a dozen similar silhouettes beside it, while they could hear distinctly the talk that was passing overhead.

wilder had some knowledge of the comanche tongue, and could make out most of what was being said. amidst exclamations that spoke of vengeance there were words in a calmer tone—discussion, inquiry, and conjecture.

from these it could be understood that the pursuers had separated into two parties, one following on the false track, by the path which the guide had baited for them, the other coming direct up the right and true one.

there were bitter exclamations of disappointment and threats of an implacable vengeance; and the fugitives, as they listened, might have reflected how fortunate they had been in discovering that unfathomed hole. but for it they would have already been in the clutches of a cruel enemy.

however, they had little time for reflection. the talk overhead at first expressed doubts as to their having descended the shaft, but doubts readily to be set at rest.

the eyes of the indians having failed to inform them, their heads were withdrawn; and soon after a stone came tumbling down the cavity.

something of this kind, wilder had predicted; for he flattened himself against the wall behind, and stood as “small” as his colossal frame would permit, having cautioned his companion to do the same.

the stone passed without striking them, and went crashing on till it struck on the bottom below.

another followed, and another; the third creasing hamersley on the breast, and tearing a couple of buttons from his coat.

this was shaving close—too close to be comfortable. perhaps the next boulder might rebound from the wall above and strike one or both of them dead.

in fear of this result, they commenced groping to ascertain if the ledge offered any better screen from the dangerous shower, which promised to fall for some time longer.

good! hamersley felt his hand entering a hole that opened horizontally. it proved big enough to admit his body, as also the larger frame of his companion. both were soon inside it. it was a sort of grotto they had discovered; and, crouching within it, they could laugh to scorn the storm that still came pouring from above; the stones, as they passed close to their faces, hissing and hurtling like aerolites.

the rocky rain at length ended. the indians had evidently come to the conclusion that it was either barren in result, or must have effectually performed the purpose intended by it, and for a short time there was silence above and below.

they who were hidden in the shaft might have supposed that their persecutors, satisfied at what they had accomplished, were returning to the plain, and had retired from the spot.

hamersley did think so; but walt, an old prairie man, more skilled in the indian character, could not console himself with such a fancy.

“ne’er a bit o’ it,” he whisperingly said to his companion. “they ain’t agoin’ to leave us that easy—not if horned lizard be amongst ’em. they’ll either stay thar till we climb out agin, or try to smoke us. ye may take my word for it, frank, thar’s some’ut to come yet. look up! didn’t i tell ye so?”

wilder drew back out of the narrow aperture, through which he had been craning his neck and shoulders in order to get a view of what was passing above.

the hole leading into the grotto that held them was barely large enough to admit the body of a man. hamersley took his place, and, turning his eyes upward, at once saw what his comrade referred to. it was the smoke of a fire, that appeared in the act of being kindled near the edge of the aperture above. the smoke was ascending towards the sky, diagonally drifting across the blue disc outlined by the rim of rock.

he had barely time to make the observation when a swishing sound admonished him to draw back his head; then there passed before his face a ruck of falling stalks and faggots. some of them settled upon the ledge, the rest sweeping on to the bottom of the abyss.

in a moment after the shaft was filled with smoke, but not that of an ordinary wood fire. even this would have been sufficient to stifle them where they were; but the fumes now entering their nostrils were of a kind to cause suffocation almost instantaneously.

the faggots set on fire were the stalks of the creosote plant—the ideodondo of the mexican table lands, well known for its power to cause asphyxia. walt wilder recognised it at the first whiff.

“it’s the stink-weed!” he exclaimed. “that darned stink-weed o’ new mexico! it’ll kill us if we can’t keep it out. off wi’ your coat, frank; it are bigger than my hunting skirt. let’s spread it across the hole, an’ see if that’ll do.”

his companion obeyed with alacrity, stripping off his coat as quickly as the circumscribed space would permit. fortunately, it was a garment of the sack specialty, without any split in the tail, and when extended offered a good breadth of surface.

it proved sufficient for the purpose, and, before the little grotto had become so filled with smoke as to be absolutely untenable, its entrance was closed by a curtain of broadcloth, held so hermetically over the aperture that even the fumes of assafoetida could not possibly have found their way inside.