But in spite of his warnings to himself, he felt panic rising within him. He was completely, hopelessly lost! CHAPTER XVI The Lake of Darkness Rick sat with his back against the cold surface of a stalagmite column. His head drooped with weariness and his throat ached from yelling. He had retraced his steps a dozen times or more. He had lost count. But none of the passages took him back to his friends, nor had his yelling of their names brought a response. He forced himself into a semblance of calmness and tried to think. What was he to do? He eyed the beam of his flashlight and realized that he ought to conserve the batteries. He turned it off, and dead, silent blackness closed in about him. True blackness is rare. It cannot be found by closing shutters or curtains in a room, even at night. Some light always penetrates man-made rooms unless they are designed, as very few are, for total darkness. Rick never had experienced it before, and it was frightening. He had to take a firm grip on himself to keep from getting panicky. But if the underground caverns were completely without light, they were not completely without sound. As Rick sat quietly he began to hear the slow drip of water. It was the slow drip of centuries that had produced the weird limestone formations of the caves. He began to talk quietly to himself, and the sound of his own voice was better than listening to the slow dripping of water. "I can't stay here. The others wouldn't have any more chance of finding me than I have of finding them. But if I leave here, I'm taking a chance. I might go so deep into the caves that I'd never find my way out again, or see any of the others again." He had visited some of the limestone caverns of Virginia, and he had read of the New York and Kentucky caverns. He knew that even in America there were endless series of caves that never had been fully explored. This fabled Tibetan place might extend on forever. "On the other hand," he continued to himself, "if I keep moving, I might stumble on the big cave under the Black Buddha again. It's less than a fifty-fifty chance. A whole lot less. But it's a chance and I'd better take it." He didn't let himself think of what would happen if he failed to find his way back. He got to his feet and switched on his light again. By contrast with the total darkness, the reflection of the beam on the limestone walls was brilliant sunlight. He had to wait while his eyes adjusted themselves to the light. Then he flashed the beam around. There were passages going in every direction. "Which way do I go?" he asked himself. It was a tossup. He remembered an old trick and spat into the palm of his hand. Then, with the forefinger of his other hand, he slapped the spittle sharply. The biggest drop flew between two limestone hour-glasses that formed one passage. He hitched up the camera case on his shoulder, picked up his rifle, and started forward.