Wood obeyed. His fears supplied him with unwonted vigour. Though the starling was more than two feet above the level of the water, he alighted with his little charge--which he had never for an instant quitted--in safety upon it. Poor Ben was not so fortunate. Just as he was preparing to follow, the wherry containing Rowland and his men, which had drifted in their wake, was dashed against his boat. The violence of the collision nearly threw him backwards, and caused him to swerve as he sprang. His foot touched the rounded edge of the starling, and glanced off, precipitating him into the water. As he fell, he caught at the projecting masonry. But the stone was slippery; and the tide, which here began to feel the influence of the fall, was running with frightful velocity. He could not make good his hold. But, uttering a loud cry, he was swept away by the headlong torrent. Mr. Wood heard the cry. But his own situation was too perilous to admit of his rendering any assistance to the ill-fated waterman. He fancied, indeed, that he beheld a figure spring upon the starling at the moment when the boats came in contact; but, as he could perceive no one near him, he concluded he must have been mistaken. In order to make Mr. Wood's present position, and subsequent proceedings fully intelligible, it may be necessary to give some notion of the shape and structure of the platform on which he had taken refuge. It has been said, that the pier of each arch, or lock of Old London Bridge, was defended from the force of the tide by a huge projecting spur called a starling. These starlings varied in width, according to the bulk of the pier they surrounded. But they were all pretty nearly of the same length, and built somewhat after the model of a boat, having extremities as sharp and pointed as the keel of a canoe. Cased and ribbed with stone, and braced with horizontal beams of timber, the piles, which formed the foundation of these jetties, had resisted the strong encroachments of the current for centuries. Some of them are now buried at the bottom of the Thames. The starling, on which the carpenter stood, was the fourth from the Surrey shore. It might be three yards in width, and a few more in length; but it was covered with ooze and slime, and the waves continually broke over it. The transverse spars before mentioned were as slippery as ice; and the hollows between them were filled ankle-deep with water.