By the time I had completed my survey of the exterior of the tower the ape had evidently come to the conclusion that he could not demolish the barrier that kept him from me and I hoped that he would abandon the idea entirely and depart. But when I lay down on the floor and placed an ear close to the door I could plainly hear him just below as he occasionally changed from one uncomfortable position to another upon the small ladder beneath me. I did not know to what extent these creatures might have developed pertinacity of purpose, but I hoped that he might soon tire of his vigil and his thoughts be diverted into some other channel. However, as the day wore to a close this possibility seemed to grow more and more remote until at last I became almost convinced that the creature had determined to lay siege until hunger or desperation forced me from my retreat. How longingly I gazed at the beckoning hills beyond the city where lay my route toward the southwest--toward fabled Jahar. The sun was low in the west. Soon would come the sudden transition from daylight to darkness, and then what? Perhaps the creature would abandon its vigil; hunger or thirst might attract it elsewhere, but how was I to know? How easily it might descend to the bottom of the tower and await me there, confident that sooner or later I must come down. One unfamiliar with the traits of these savage creatures might wonder why, armed as I was with sword and pistol, I did not raise the trap door and give battle to my jailer. Had I known positively that he was the only white ape in the vicinity I should not have hesitated to do so, but experience assured me that there was doubtless an entire herd of them quartered in the ruined city. So scarce is the flesh they crave that it is their ordinary custom to hunt alone, so that in the event that they make a kill they may be more certain of retaining the prize for themselves, but if I should attack him he would most certainly raise such a row as to attract his fellows, in which event my chance for escape would have been reduced to the ultimate zero.