Like a creeping thing, for he scarce used hand or foot at all, Richard slowly crawled and slid along the sloping roof, then swiftly over the vertex, while the patrol was at the most distant portion of his round, and then once more, motionless and almost breathless, he lay down behind the western parapet. The exercising-yard, into which it was his object to drop, was just below him; but it was necessary to find some object to which to fasten his rope; and here he perceived how futile would have been his plan of escape without assistance from without; for here, having slid down it, he must needs leave his rope tied to a neighboring chimney. There was not length enough to cut off, and be of any service afterward for the descent of the external wall, nigh sixty feet in height. If Balfour failed him, it was now, indeed, clear to him that his whole design must fail. Yonder towering wall, higher even than his own present elevated position, could never be scaled by foot and hand, with only the help of a spout--nay, he doubted whether, even if he found the promised rope in position, he could even make use of that; for, though agile, he had none of the sailor's cunning. He made fast the coil which he had with him, however, and watching his opportunity, slid off the parapet into space. Such a feat seems easy enough to read of; but to slide without noise down a loose and swinging rope for so great a distance is no slight task to one unused to such gymnastics; and, besides, he had to check himself at intervals (which took the skin off from his hands, although at the time he did not feel it), lest he should suddenly reach the ground with a dull thud. He accomplished this in safety, and once more paused, his back pushed hard to the prison wall, while the warder passed, whose form he could now even make out, it was so immediately above him; then he crossed the yard with a swift but anxious step to its north corner, and peered about in the gloom for the promised rope; the spout was there, smooth and ineffectual enough as a means of exit, but no rope.