It may be true; but, whether or no, it seemed as if the four English castaways had been stricken with this inexplicable paralysis. Despite the hoarse roaring of the breakers, despite the shrieking and whistling of the wind, despite the dust constantly being deposited on their bodies, and entering ears, mouth, and nostrils,--despite the stifling sensation one would suppose they must have felt, and which should have awakened them,--despite all, they continued to sleep. It seemed as if that sleep was to be eternal! If they heard not the storm that raged savagely above them, if they felt not the sand that pressed heavily upon them, what was there to warn, what to arouse them from that ill-starred slumber? CHAPTER XII. A MYSTERIOUS NIGHTMARE. The four castaways had been asleep for a couple of hours,--that is, from the time that, following the example of the young Scotchman, they had stretched themselves along the bottom of the ravine. It was not quite an hour, however, since the commencement of the sand-storm; and yet in this short time the arenaceous dust had accumulated to the thickness of several inches upon their bodies; and a person passing the spot, or even stepping right over them, could not have told that four human beings were buried beneath,--that is, upon the supposition that they would have lain still, and not got startled from their slumbers by the foot thus treading upon them. Perhaps it was a fortunate circumstance for them, that by such a contingency they might be awakened, and that by such they _were_ awakened. Otherwise their sleep might have been protracted into the still deeper sleep--from which there is no awaking. All four had begun to feel--if any sensation while asleep can be so called--a sense of suffocation, accompanied by a heaviness of the limbs and torpidity in the joints,--as if some immense weight was pressing upon their bodies, that rendered it impossible for them to stir either toe or finger. It was a sensation similar to that so well known, and so much dreaded, under the name of _nightmare_. It may have been the very same; and was, perhaps, brought on as much by the extreme weariness they all felt, as by the superincumbent weight of the sand. Their heads, lying higher than their bodies, were not so deeply buried under the drift; which, blown lightly over their faces, still permitted the atmosphere to pass through it. Otherwise their breathing would have been stopped altogether; and death must have been the necessary consequence.