Maybe Dixon had found two small nuggets worth at least a hundred dollars each. He had also washed out some of the sand and gotten several ounces of almost pure gold. Everything on hand went into the hole before it was filled up with dirt and covered with the tree trunk. Sunday passed, and then they went at the cavern work in earnest. They cleaned out a place at the rear several yards in extent. Here they found a big slit, extending upward, but the rocks were exceedingly hard to remove. "We ought to have some powder to blow them apart," said Mark. "We must be careful," said Maybe Dixon. "We don't want a cave-in." By the middle of the week they had twelve more nuggets and another small bag of dust. "Ten thousand dollars' worth more," said Bob, when the find was placed in "the bank," as the hole had been designated. "We are getting wealthy, sure!" Thursday found them all at the cavern, working away as industriously as ever. It was the middle of the forenoon and each had found a small nugget. In the center of the cavern floor was a heap of sand filled with golden grains, waiting to be washed. They were all happy and Bob was whistling merrily. "Guess I'll go out and take a look around," said Si, and started for the opening. Mark, Bob, and Maybe Dixon were at the rear of the cavern, working around a sharp, triangular rock. They imagined some more nuggets might be underneath. "Hark!" cried Mark, suddenly. "What's that?" All stopped work and listened. There was a strange rumble overhead. It kept growing louder and louder. "Look out for the landslide!" yelled Si, rushing into the open air. "Come out, or you'll be buried alive!" The others heard the warning and started to leap from the hollow where they were working. But before they could do so the rumble burst forth like thunder, all but deafening them. Then down came some sand and small stones, all but burying the three. The mouth of the cavern was darkened, as a mass of dirt and rocks blocked it up completely. "We are shut in!" spluttered Bob, as soon as he could speak. The rumble stopped, but soon it started again, as another mass of dirt slid down the mountain-side, directly over the cavern. Then came a quiver as of an earthquake, and absolute quietness followed. "Boys, are you hurt?" The question came from Maybe Dixon. He was up to his knees in loose dirt. "I am all right," answered Mark. "A small rock hit me on the shoulder, but the hurt doesn't count," returned Bob. "Where is Si?" "I think he got out," said Mark. "But I am not certain." "If he did get out maybe he is worse off than we are," said Maybe Dixon. "The landslide must have carried him down to the valley, or killed him." For several minutes the three inside the cavern did not know what to do. "One thing is certain," said Mark. "If we don't want to be smothered we'll have to dig our way out." "True, but we don't want to risk a cave-in," said Maybe Dixon. "We'll have to go at it easy-like."