Had it not been for their fatigue they might have gone farther. Since the moon had consented to show herself, there was light enough to travel by; and they might have proceeded on--either through the sand-dunes or along the shore. But of the four there was not one--not even the tough old tar himself--who was not regularly done up, both with weariness of body and spirit. The short slumber upon the spit--from which they had been so unexpectedly startled--had refreshed them but little; and, as they stood upon the summit of the sand-hill, all four felt as if they could drop down, and go to sleep on the instant. It was a couch sufficiently inviting, and they would at once have availed themselves of it, but for a circumstance that suggested to them the idea of seeking a still better place for repose. The land wind was blowing in from the ocean; and, according to the forecast of Old Bill--a great practical meteorologist,--it promised ere long to become a gale. It was already sufficiently violent--and chill to boot--to make the situation on the summit of the dune anything but comfortable. There was no reason why they should make their couch upon that exposed prominence. Just on the landward side of the hillock itself--below, at its base--they perceived a more sheltered situation; and why not select that spot for their resting place? There was no reason why they should not. Old Bill proposed it; there was no opposition offered by his young companions,--and, without further parley, the four went floundering down the sloping side of the sand-hill, into the sheltered convexity at its base. On arriving at the bottom, they found themselves in the narrowest of ravines. The hillock from which they had descended was but the highest summit of a long ridge, trending in the same direction as the coast. Another ridge, of about equal height, ran parallel to this on the landward side. The bases of the two approached so near, that their sloping sides formed an angle with each other. On account of the abrupt acclivity of both, this angle was almost acute, and the ravine between the two resembled a cavity out of which some great wedge had been cut,--like a section taken from the side of a gigantic melon. It was in this re-entrant angle that the castaways found themselves, after descending the side of the dune, and where they had proposed spending the remainder of the night. They were somewhat disappointed on reaching their sleeping-quarters, and finding them so limited as to space. In the bottom of the ravine there was not breadth enough for a bed,--even for the shortest of the party,--supposing him desirous of sleeping in a horizontal position. There were not six feet of surface--nor even three--that could strictly be called horizontal. Even longitudinally, the bottom of the "gully" had a sloping inclination: for the ravine itself tended upwards, until it became extinguished in the convergence of its inclosing ridges.