In the side of the hill was a deposit of iron pyrites. Not that there was anything remarkable about that. But the thing that struck me was that the vein had been recently worked! I sprang down in the pit and found on the rock traces of copper that had evidently come from soft copper tools. I knew that Austen would have needed minerals, that, indeed, if he had set up a wireless outfit in here, he must have been compelled to do an immense amount of work in collecting and refining the needed materials. I had little doubt that he had been there, but it had been evidently weeks or months ago. Any trail that he might have made through the forest would have already grown up. I thought the situation over for a while, but still there seemed nothing better to do than to follow our original plan of exploring the jungle to the north. We plunged into the crimson gloom. Without the compass we would have been quickly lost. Even with it, it was hard enough to keep in the same direction, walking over the marshy, sodden ground and breaking a path through the heavy undergrowth. We were soon covered with mud and dyed red with the stain of the weird vegetation. For many hours we struggled through a wilderness of endless sameness--a dank morass, a crimson jungle, with the dusky purple sky hanging heavily in the treetops. The bloody scarlet gloom was startling and terrible. At first the forest had been quiet, with a silence that was dead and depressing, for there were no living things about us. No birds, no insects--not even a bright moth or butterfly. It was a wilderness of death. But presently we heard, far ahead of us, a dull, constant roar, that grew ever louder as we went on. I supposed that we were approaching a great waterfall. At last it grew so loud that we had to shout when we wished one another to hear our words. I was glad of the roar, for it drowned the sound of our progress through the jungle. But the forest was so dense that there seemed little danger of our capture unless we stumbled unaware on the habitation of the _Krimlu_. Abruptly the jungle ended, and we stepped out on a bare ledge of stone. Before us was one of the most magnificent spectacles that I have beheld. To the west of us a great black cliff rose perhaps a thousand feet--until it was almost lost against the lowering, smoky purple of the sky. Over it plunged a vast sheet of the glowing white liquid of the Silver Lake, falling in a gigantic unbroken arch to the immense pool beneath us, where it broke, with a deafening roar, into a gleaming bank of soft silver haze. Surrounding the black rock rims of the pool, the gloomy crimson of the forest closed in. The pool was a thousand feet across. The whole scene was colossal; it was awe-inspiring and impressive for the strangeness and intensity of its color.