As already said, the mirth of the three midshipmen was brought to a quick termination. It ended on the instant of Sailor Bill's disappearance behind the spur of the sand-hills. At the same instant all three came to a stop, and stood regarding one another with looks of uneasiness and apprehension.

All agreed that the maherry had made away with the old man-o'-war's-man. There could be no doubt about it. Bill's shouts, as he was hurried out of their hearing, proved that he was doing his best to bring to, and that the "ship of the desert" would not yield obedience to her helm.

They wondered a little why he had not slipped off, and let the animal go. They could not see why he should fear to drop down in the soft sand. He might have had a tumble, but nothing to do him any serious injury,—nothing to break a bone, or dislocate a joint. They supposed he had stuck to the saddle, from not wishing to abandon the maherry, and in hope of soon bringing it to a halt.

This was just what he had done, for the first three or four hundred yards. After that he would only have been too well satisfied to separate from the camel, and let it go its way. But then he was among the rough, jaggy rocks through which the path led, and then dismounting was no longer to be thought of, without also thinking of danger, considering that the camel was nearly ten feet in height, and going at a pitching pace of ten miles to the hour. To have forsaken his saddle at that moment would have been to risk the breaking of his neck.

From where they stood looking after him, the mids could not make out the character of the ground. Under the light of the moon, the surface seemed all of a piece,—all a bed of smooth soft sand! For this reason were they perplexed by his behavior.

There was that in the incident to make them apprehensive. The maherry would not have gone off at such a gait, without some powerful motive to impel it. Up to that moment it had shown no particular penchant for rapid travelling, but had been going, under their guidance, with a steady, sober docility. Something must have attracted it towards the interior. What could that something be, if not the knowledge that its home, or its companions, were to be found in this direction?

This was the conjecture that came simultaneously into the minds of all three,—as is known, the correct one.

There could be no doubt that their companion had been carried towards an encampment; for no other kind of settlement could be thought of in such a place. It was even a wonder that this could exist in the midst of a dreary, wild expanse of pure sand, like that surrounding them. Perhaps, thought they, there may be "land" towards the interior of the country,—a spot of firm soil, with vegetation upon it; in short, an oasis.

After their first surprise had partially subsided, they took counsel as to their course. Should they stay where they were, and wait for Bill's return? Or should they follow, in the hope of overtaking him?

Perhaps he might not return. If carried into a camp of barbarous savages, it was not likely that he would. He would be seized and held captive to a dead certainty. But surely he would not be such a simpleton, as to allow the maherry to transport him into the midst of his enemies.

Again sprang up their surprise at his not having made an effort to dismount.

For some ten or fifteen minutes the midshipmen stood hesitating,—their eyes all the while bent on the moonlit opening, through which the maherry had disappeared. There were no signs of anything in the pass,—at least anything like either a camel or a sailor. Only the bright beams of the moon glittering upon crystals of purest sand.

They thought they heard sounds,—the cries of quadrupeds mingling with the voices of men. There were voices, too, of shriller intonation, that might have proceeded from the throats of women.

Colin was confident he heard such. He was not contradicted by his companions, who simply said, they could not be sure that they heard anything.

But for the constant roar of the breakers,—rolling up almost to the spot upon which they stood,—they would have declared themselves differently; for at that moment there was a chorus being carried on at no great distance, in a variety of most unmusical sounds,—comprising the bark of the dog, the neigh of the horse, the snorting scream of the dromedary, the bleat of the sheep, and the sharper cry of its near kindred the goat,—along with the equally wild and scarce more articulate utterances of savage men, women, and children.

Colin was convinced that he heard all these sounds, and declared that they could only proceed from some encampment. His companions, knowing that the young Scotchman was sharp-eared, made no attempt to question his belief; but, on the contrary, gave ready credence to it.

Under any circumstances it seemed of no use to remain where they were. If Bill did not return, they were bound in honor to go after him; and, if possible, find out what had become of him. If, on the other hand, he should be coming back, they must meet him somewhere in the pass,—through which the camel had carried him off—since there was no other by which he might conveniently get back to them.

This point determined, the three mids, setting their faces for the interior of the country, started off towards the break between the sand-hills.