Fic had been doing a lot of thinking while this hasty consultation went on. He had not studied his physics for nothing, and he was sure he had the key to the problem. “Please, Mr. Sanderson, may I speak?” The four men looked down and saw a boy in a short jacket, with eyes that were burning with excitement, and Mr. Sanderson said, in amazement: “Hello! Who are you, and what are you doing here?” “If you please,” said Fic, drawing himself up to the dashboard in his excitement, “I know how to put out the fire!” “You do, do you! Well, speak up quick! It’ll be worth a good many thousand dollars and perhaps a few lives, if you do.” “Take off the lid of the tank on top and pour water into the tank. The wind blows the fire to one side, and if you can once get a hose in you will do it.” “How will that put the fire out?” cried the superintendent. “It’s the specific gravity. Water is denser than naphtha and will sink to the bottom. If it doesn’t explode when you open it, it won’t afterward. The water will sink to the bottom and get into the leaky pipes.” “I believe the lad’s right,” said the fire-chief. “At all events, we’ll try it. Who’ll help?” Two or three volunteers came forward and lifted a ladder on the windward side of the car. The chief mounted and pried up the lid. No explosion followed, and on thrusting in his hand he found that the naphtha was still very near the top. If the fire should reach and scatter it there would be no hope of saving the buildings, he knew, and even the vapor was dangerous. He called for a hose, thrust it in at the vent, and pulled down the lid to keep the vapor in. Then he climbed down to watch the result. Already, as he reached the ground and turned to look, the flame had diminished. In five minutes the fire was out, and water was dripping from the cooled end of the leaky pipe, which was soon tied up and made safe. Not only was the danger over, but almost the whole contents of the tank were saved. No sooner was the work of repair over by the gleam of hastily lighted lanterns than the superintendent, like a man relieved by miracle, suddenly pulled himself up from the side of the disabled car and looked about him. Then he shouted, “Where’s that boy?” Nobody knew. For the moment they had forgotten all about the boy in thinking of the escape from peril; and as for John Paul, so soon as he saw that the fire was out and his faith in the principle of specific gravity vindicated, his interest had ceased, and he had turned across the flooded tracks toward home. He slipped quietly in, got to bed by half past four without disturbing anybody, and was up as usual when his mother called him to help her with the morning work. He never troubled her with his experiments, and it did not occur to him to speak of the night’s adventure.