But the restless Kenneth was far from remaining inactive. He continued his investigations on the sides of the edifice away from the view of the invaders. "I have it!" he exclaimed. "See that spout? It runs close to that open window, you'll notice. If you can give me a hand I can lower myself sufficiently to clear the bulging top of the spout, and the rest will be easy." The scheme looked feasible, and Rollo made no further objection. It was risky, of course, but with ordinary caution Kenneth could reach the window after he had descended about ten feet of piping--which was infinitely better than climbing down sixty feet or so of copper tape. Having secured a firm hold upon the spouting, Kenneth began to descend hand-over-hand fashion, although he took care to let his weight act as perpendicularly as possible, lest any outward thrust with his feet might wrench the securing nails of the pipe from the cement. Without mishap he descended until he was almost on a level with the open window, the iron casement frame of which swung outward. Then, to his consternation, Kenneth found that he had miscalculated the distance, and that the upper edge of the casement was six inches beyond his reach. At the same moment he became aware of the effect of his collision with the Uhlan. His limbs began to feel stiff and cramped. Frantically he began to clamber back to the parapet, but the effort was too great. With a sickening shudder he felt the pipe working loose from the wall. For the first time in his attempt he gave a downward glance that wellnigh proved fatal. The pavement, fifty feet below, exercised a horrible fascination. "What's wrong?" enquired Rollo anxiously, for he could see by his chum's ashen-grey face that something was amiss. "Can't reach the window," gasped Kenneth. "I believe I've strained a muscle, too. I must have a shot at climbing all the way down." "Hold hard a moment," exclaimed Rollo. "I'll half-close the window and you might reach it." "Be quick, then," gasped his unfortunate comrade. "I can't hold on much longer." At that moment he failed to see how Rollo could reach the casement, although his chum's confident assertion cheered him. He knew by experience that Rollo rarely suggested a plan without being able to carry it through. Already Rollo was at work. Producing a length of stout string from his pocket, he removed his boot. To this he attached the string, which was about four yards in length. Leaning over the parapet he lowered his boot until it dangled an inch or so before the iron rod that held the window open. A rapid upward jerk and the casement was free to swing; a little skilful manoeuvring and the weighted string drew the hitherto unattainable window frame within Kenneth's reach.