The buckets were nearly empty, and he felt that it would be better for what was left in one to be poured into the other, so that the supplying might still go on while more was fetched, when it suddenly struck him that there was something wrong. In the darkness he could dimly make out two or three tall blacks pressing forward toward where the white-clothed sailors were dispensing the precious fluid, and it struck him that their aspect was threatening. The next moment he set the idea down as being imaginative, and the result of the unreal-looking, dreamy scene before him. For it was impossible, he argued, for the slaves to be about to resent the treatment they were receiving. "It's my head all in a whirl," he said to himself; "and it's just like I used to feel when I was ill and half dead in the boat." But the next minute he felt that the first idea was correct; something was wrong, and it struck him that the prisoners were going to make an attack. But he could not be sure; the darkness was too thick, and the excitement and horror of the whole scene made his imagination play strange pranks. At one moment he could see right back into the fore part of the hold where it was crowded with writhing, struggling beings; the next the mist closed over it apparently, and he could only make out gleaming eyes and shadows sweeping toward him and fading away, to appear at the side or hovering over his head. "Yes; it's all from a disordered imagination," he said to himself; and he had hardly come to this conclusion, when he knew that he was gazing at the real, for dimly-seen, there before him was a crowd of figures surrounding the two black sailors. A harsh sound arose--a mingling of muttered cries and savage growlings as of wild beasts; there was the noise of the buckets being knocked over, of a fierce struggle and heavy blows, and a hot, sickening wave of mephitic air was driven outward. Thoroughly alarmed now, Mark shouted for help, and was then thrust aside as one of the blacks whom he had brought down made for the hatchway, and in the brief glance he obtained in the light which shone down from above, he saw that the man was covered with blood. For a moment or two, weak still from his late illness, Mark felt completely prostrate and unable to act; but he recovered himself as quickly, and started forward to grasp the black's arm. "Hurt?" he cried. The man dropped back from the ladder to gaze at him, and then uttered a few words excitedly as he pointed back into the forward part of the dark hold. "Here, stand aside!" cried the lieutenant, as he stepped down into the noisome hold, followed by Tom Fillot and a couple of the crew, each man with sword or cutlass in hand. "Now, Mr Vandean, quick; an attack?" "Yes, sir; the slaves attacked our two men. One of them's badly wounded."