Then for the first time I saw, to my right, fixed so that it almost touched the floor of the hut, a great round brass object, mounted on an enormous tripod, which, again, stood on a platform. In front of this was a large square thing like a mammoth rectangular condenser, such as is used for photographic enlarging and other projection purposes. Had it not been for this condenser I should have taken the whole thing to be an elaborate searchlight. But, I asked myself, what would be the good of a searchlight there? Suddenly the whole truth dawned upon me. The searchlight must operate through a trap in the wall of the hut just below the floor. I leaned further in, forgetting my danger in the intoxication of sudden discovery. Only a foot or two away from me a man was working on the searchlight. Carefully taking it to pieces, he was handing the parts to another man, who was perched on the scaffold below him. He was so close to me that I could hear him breathing. I was about to wriggle back to safety when he looked up. He gave a sudden loud shout. I lay there fascinated. After all, I thought, before they can reach me I can slip out and edge round the cliff, run down on to the shore, and get away in the motor-boat. But I had reckoned without my host. Even as the man shouted, and the others left their work to see what was the matter, Fuller dashed out from behind the platform, gave one terrified look at me, and, flinging himself at the wall of the cavern, threw all his weight on a rope which dangled there. I scuttled to my feet, intending to make a bolt for it. But the boards shivered beneath me, and, before I could realise what was happening, I found myself hurtling through the air to the floor of the cavern below. CHAPTER XVII. SOME GRAVE FEARS. And now, as the reader will readily understand, I must continue the story as it was afterwards related to me. Myra, the General, and Dennis sat up and waited for me till the early hours of the morning, but I did not return. The young people did what they could to assure the old man that my sudden and unexpected disappearance had been entirely voluntary, and Dennis, who had found my note, as soon as he put on his cap to stroll out casually, and see where I had got to, gave him subtly to understand that it was really part of a prearranged plan, and Myra at length persuaded him to go to bed at midnight. When I failed to put in an appearance at breakfast-time, however, even they began to be a trifle alarmed, but they did their best to conceal their fears. They scoured the hillside and then went down to the landing-stage. Dennis had reported the previous night that the motor-boat was still in its place when he saw Hilderman off, and it never occurred to Myra that I might make my departure in the _Coch-a-Bondhu_. "He hasn't gone by the sea, any way," Dennis announced again, as he and the girl stood on the landing-stage. "You mean the _Jenny_ is still there?" she asked.