But there was an avenging arm already raised to strike them. No enemy pursued them--the weather had hitherto been fine. Suddenly there came a change. Dark clouds gathered rapidly--thunder roared--lightning flashed vividly. It was night--Jack was standing on deck near Sambo--"Oh! what is dat?" exclaimed Sambo, as a large ball of fire struck the main-topmast head. Down it came with a crash, riving the mast into a thousand fragments. Wild, wild shrieks of horror and dismay arose. Bright flames burst forth, shewing the terror-struck countenances of the crew. Down--down sank the ship, the fierce waves washed over her decks. Jack thought his last moment had come as the waters closed over his head, while he was drawn in by the vortex of the foundering vessel; but he struck out boldly, and once more rose to the surface. He found himself among several spars with a few fathom of thin rope attached to them. He contrived to get hold of these spars, and by lashing them together to form a frail raft. This was the work of a minute. He listened for the sound of a human voice, yet he feared that he himself was the sole survivor of those who lately lived on board the slave ship. Not a sound did he hear, nothing could he see. How solitary and sad did he feel thus floating in darkness and alone on the wide ocean. Oh picture the young sailor boy, tossing about on a few spars in the middle of the Atlantic, hundreds of miles away from any land, thick gloom above him, thick gloom on every side. What hope could he have of ultimately escaping? Still he remembered that God, who had before been so merciful to him, might yet preserve his life. He had not been many minutes on his raft when he shouted again, in the hopes that some one might have escaped to bear him company. With what breathless anxiety did he listen! A voice in return came faintly over the waters towards him from no great distance. He was sure he knew it. "Is that you, Sambo?" he exclaimed.--"Yes, Jack, me. Got hold of two oars. Come to you," answered Sambo, for it was the black who spoke. After some time Sambo swam up to him, and together they made the raft more secure. It was a great consolation to Jack to have his friend with him; yet forlorn, indeed, was their condition. CHAPTER FOUR.