One day a boy of twelve years was tending cattle by the side of a railway line. Suddenly he noticed that a small railway bridge was about to collapse. A little later, he remembered that a mail train was supposed to cross in about half an hour. Then he thought he would go and inform me of the authority of the nearest railway station. He was about to go when he heard a whistle. A passenger train was coming. He could not think of what to do. Then, he remembered that he ought to show a red signal to stop the train. Suddenly, he remembered that he wore a red shirt. He put off his shirt hurriedly and started to wave it raising his hand standing on the rail line. After a while, the driver of the train saw the red signal and slowly stopped the train. He got down from the train angrily and came to the boy to know the matter. Some passengers also came to him. Everybody was furious to ask him the real incident. Then, he told them everything and showed that the small railway bridge was about to collapse. Now, the driver understood the matter and showed his gratitude to the boy. He along with the passengers thanked the boy again and again for saving their lives.