Then, after what seemed to be an age of terrible suspense, the Sub saw the sergeant return to his men. The soldiers recovered their arms, faced about, and marched towards the outer gateway. The light vanished, and the tramp of their feet was soon lost in the moaning of the wind.
Hamerton waited no longer; at any moment the jailers might intrude. Noiselessly he allowed the coil of blanket-rope to drop into space, then, grasping one of the bars which still remained, he assisted Detroit to clamber up beside him.
"You go first," he whispered. "You're lighter than I am. If the rope should break when I descend, don't wait, but clear out."
"I won't," replied Detroit. "We'll stand by each other at all costs. Well, here goes!"
The next moment he was lost to sight. Hamerton could feel the rope stretching and jerking under the strain of the descending man's weight. Presently the tension ceased. The American had reached the steps beneath the window.
Without hesitation Hamerton followed. He realized that should the soft fabric give way a fall of about ten feet, followed by a headlong tumble down the stone steps, would be the inevitable result, and to a man weighing close on fifteen stone that was far from pleasant to contemplate.
But the rope stood the strain, and with a muffled exclamation of thankfulness Hamerton felt his feet touched one of the stone steps.
"Heave away!" he whispered, placing the rope in Detroit's hands. Both men pulled their hardest. The blanket rope parted, leaving about ten feet of it in their possession. Then the American saw his companion do a strange act. Hamerton drew a packet from his pocket, and, holding his nose tightly with his left hand, scattered something on the ground. It was as much as Detroit could do to restrain his curiosity.
The outer wall with its array of spikes presented little difficulty. Detroit clambered on to Hamerton's shoulder, grasped one of the revolving rods, and passed the bight of the rope around it. By this means he was able to draw himself up and crouch astride of the obstacle until Hamerton swarmed up beside him. The drop on the other side was a more nerve-racking ordeal, for neither of the fugitives knew what was beneath them. Fortunately it was a vegetable garden belonging to one of the jailers, and the soft earth effectually neutralized the otherwise nasty jar of a twelve-foot drop.
Once again Hamerton stopped to scatter something from the packet. Detroit recognized it now. It was pepper. It nearly made him sneeze. Then he realized what his companion was about. Hamerton meant to baffle the bloodhounds that were kept on the island for the purpose of assisting the sentries in arresting all suspicious characters and maintaining the jealously guarded secrets of the island fortress.