There were two slight elements only in their favor. One was the passageway, through the rock, where clean fresh air was constantly flowing upward; the other was the very breeze itself that swept the smoke upon them. It frequently split the cloud of black and gray upon two juttings of the headland, or even beat it down and mingled its own overheated but acceptable ozone with the otherwise stifling fume. Anger and horror together had lodged in Grenville's being. That the Dyaks would soon attempt a sneak upon them, under cover of the cloud, he felt was as certain as that hideous death must be their portion, were this business sufficiently prolonged. Even retirement to the cavern could avail them nothing but a short delay of the fate they must finally face when their food and water should be presently exhausted. Under cover of the drifting smudge, he sent Elaine to the passage. As long as a breath remained in his lungs he resolved he would not desert his post, where he waited for attack by the trail. To permit the fiends to swarm upon the terrace, destroy or capture his powder and the gun, and prison himself and Elaine in the narrow gallery, was a thought that aroused him through and through. All further contemplation of his scheme for alluring the Dyaks to the cavern was necessarily abandoned. The most he could do was to watch as before, and, perhaps, convey his bombs and stores to the passage, as time and his highly essential vigilance permitted. Back and forth through the smoke he moved upon the hill, seeking the better air that came occasionally through the billows, and listening intently for the faintest sound from the always ready alarm. When an hour had gone and no attack had developed, his heart underwent a new despair. He began to doubt that the Fates would supply him an opportunity for further retaliation on the fiends below, who could finally overcome him with the fumes. The drift of smoke was intermittently broken, near the trail, where apparently a current of wind that assumed a rotation as it rose through a half-round niche of considerable dimensions in the wall, swept vertically upward to lift the billowing cloud. Thus for at least a portion of the time Grenville could glimpse the ledge behind the trail where besiegers must finally pass. So dense became the reek, however, that he feared his post must soon become insupportable. There was neither time nor air in which to arrange a longer fuse, which, as a matter of fact, would be too long for accurate work with the gun. He knew at last the hour was nearing sunset, and silence still seemed to roll with the smoke across the enveloped terrace. His eyes were burningly filled with water; his head had begun to ache. He went weakly over towards the gallery, intent upon breathing a little fresher air before resuming his duties.