"Yes. We'll waste no time now we are here," said the ranger. "Stand there awhile and get your breath," he said to Roye, who was panting with his run. "I will go first, and what I do you must copy." Getting a foothold on the trunk of the tree, he climbed among the foliage and disappeared. Herman could hear him mounting, the rustle of the branches telling how he was moving. "Art coming?" Engel asked presently, in a tone which warned the others to be cautious. "I'm coming," Herman whispered back, but he turned to Roye. "You had better go next, then I shall know that you are safe. I am used to climbing trees, but possibly you are not." "'Tis true," said the elder man, but he followed Engel, and before long word came in the darkness that he was safe. When Herman stood with the others in the great fork, which formed a natural platform, the ranger dropped on his knees, and felt about in the darkness with his hand. When he had found what he wanted, he began to descend into the body of the tree, the trunk proving to be hollow. The others could hear the sound of his feet, as though he stepped on iron. The fancy became reality when Engel produced a light, and while he held a lantern in his hand, they saw him below, waiting for them to follow. "Put your feet on those irons, and hold tight with your hands, or you may get a nasty fall," he whispered, pointing to some iron loops which had been driven into the inside of the tree, forming what was equivalent to a ladder. Herman descended, feeling with his feet for footing as he went, Roye following closely. Looking around them curiously when they stood in a group, they saw all manner of insects crawling about, startled by the light and this unwonted invasion of their domain. Many of them left shiny tracks behind them, while some insects, attracted by the lantern, flew against its horny sides. It was an unpleasant sight, but they had other business on hand, and they went about it with that quick glance at their surroundings. Handing the lantern to Herman, the ranger bent down and prodded the floor with his hunting-knife. At every prod there was an answering metallic sound. "That's iron," said Herman, who was watching eagerly. "Yes. Don't you remember what the plan showed you?" Engel replied. "Ha! This seems to be what I want." He had driven his knife into a crevice, and, scraping the earth away, as he moved along, with the point, he marked out a square space. Driving in the point of the tempered steel, he raised an iron plate which worked on hinges, and, getting his hands to it when it had come a little way, he threw it back against the tree's side, and looked into a hole, the bottom of which was lost in blackness. Here, again, were iron clamps by which Engel descended carefully, for some distance, until his foot touched solid ground. Herman followed and found himself in a cavernous space.