The candles had gone out, but the lantern was still lit, and holding this up they made an examination of the cavern. The front was blocked up so completely that the shovel did not pass through it. "I think we had better cut upward," said Maybe Dixon. "But be mighty careful." They set to work, slowly and cautiously. The dirt was hard and mixed with stones, and sometimes a shower came down on their heads. What fell was banked up for a place to stand upon while going higher. An hour passed and the air in the cavern began to grow foul. Mark was the first to notice this. "We ought to have ventilation," he remarked. "This makes me sleepy," said Bob. "Don't go to sleep, or you'll never wake up!" cried the old miner. "Keep at the work and we'll be sure to git out sooner or later." Another hour passed and the air became so bad they could hardly breathe. They were all thirsty, but no water was at hand. They looked at each other in despair. "We have got to get out!" said Mark, determinedly. "Come on, don't give up yet." Growing desperate, they attacked the top of the cavern with vigor, letting the dirt and stones fall all around them. Then down came a big rock, just grazing Bob's head. "I'm glad it didn't land on my head," said the boy, after leaping to one side. "I see a streak of light!" ejaculated Mark and pointed upward. The light was there, a single ray of sunshine, coming from a slit in the rocks. Mark sniffed the air. "That is better, anyhow," said he. "With that opening we shan't smother to death." They had now to work with greater care than ever, piling up the rocks around them, as a support for what was left of the roof of the cavern. But their labors told, and inside of another hour Mark was able to stand on Maybe Dixon's shoulders and drag himself up out of the cave to a shelving rock which kept the rest of the cavern roof from caving in. Then Bob came up, after which the two youths hauled the old miner up by means of the pick handle and a short rope that was handy. "Thank heaven we are out of that!" said Mark, sincerely. "We must look for Si," came from Bob. "Si! Si!" he called out. "Where are you?" No answer came back. Then they looked toward the spot where the tent had been. The shelter was knocked flat, but otherwise the landslide had apparently done little damage in that direction. "Let us go over to the tent," said Bob. "I am dying for a drink of water. Then we can look for poor Si." They got out of the dirt and loose rocks as best they could and walked over to the fallen tent. Some round rocks were lying about and one had sent the tree trunk rolling down the hill, thus bringing down the canvas. "The hole!" yelled Maybe Dixon, suddenly. "The hole! Somebody has dug up our gold!" He pointed to the hole, and they all ran in that direction. The dirt was scattered in all directions and near at hand lay a pick and two shovels. "It's empty!" muttered Mark, hoarsely. "Empty?" echoed Bob, faintly. "Are you sure?"