In a few minutes he reappeared with a big two horse vehicle, containing two wide seats. "Get aboard!" he called, and the boys and Mr. Post scrambled up. The horses started off slowly, Mr. Baker driving, and they turned from the single street of the little village and emerged into a country road. Arriving at the well which was to be shot the boys saw a number of men. They had just finished using the borer, and had gone down a number of hundred feet without striking oil. It was, therefore, decided to "shoot it," that is, tin cylinders, containing in all about two hundred pounds of nitro-glycerine, were to be lowered into the hole, one on top of the other. Then a heavy cylindrical weight was to be dropped down on them. The concussion would set off the explosive. The powerful stuff, it was expected, would blow a hole down through the sand and rock, and release the imprisoned oil. Mr. Baker lost no time in getting to work. Carefully as though he was handling eggs, he lowered the tins of nitro-glycerine into the deep but narrow hole. The boys, as well as Mr. Post and the workmen, had moved a safe distance away. The final arrangements were made, and then all was in readiness for dropping the "go-devil," as it is termed. Mr. Baker gave a last look around to see that all were far enough back. Then, with a wave of his hand he stooped over the hole. The next instant he was running like a deer. "He's dropped it!" exclaimed Mr. Post. "Watch it now!" It seemed as if the running man would never get to a place of safety. The boys watched with their hearts in their mouths. Suddenly there sounded a subdued roar. Then came a curious trembling of the earth, a shaking of the solid ground. Two seconds later there spouted from the hole a column of black liquid that seemed to envelope the derrick which had not been taken down. At the same time there was a roaring, whistling noise. Suddenly Mr. Post, who was watching the spouting well, shouted: "Run boys! Run for your lives! Follow me!" CHAPTER XVI MR. POST'S ADVENTURE For an instant Jack Ranger and his two comrades did not realize what Mr. Post was saying. They could see no danger near them. "What's the matter?" asked Nat. "Don't stop to ask questions! Run! Run! Run!" yelled the miner. The boys needed no further urging, but set off at top speed after Mr. Post. He halted his run to allow the boys to catch up to him. Then, as he gave a glance backward, he yelled: "Too late! Duck!" The boys found themselves being pushed forward. They stumbled and fell, and it seemed as if some heavy weight toppled on top of them. Then came an explosion that sounded like a thirteen-inch gun being set off close to their ears. They were stunned by the shock and frightened half out of their wits by the unknown terror. An instant later it was as if the sky was raining gravel, stones and sand.