The end of the trestle the entire width across had given way and fallen with a crash and now lay, a broken mass of wreckage, half on land and half in water. An open space about six feet wide yawned between Jack and the bank.

Not very much space, you think, for an agile Boy Scout trained in all sorts of athletics to cover; and, ordinarily, that would have been so. But now the ground under and beside the tracks was soft and yielding from the rain and, to make the task of jumping still more difficult, the mass of wreckage served as a dam and the water flowed out over the roadbed, making it impossible to calculate the leap.

Our Scout stood there for a long minute trying to decide what to do. If it had been only his own life that he had to consider, he would not have hesitated a second, but he had to reflect that if lost there would be no one to warn the express, which must now be very close at hand.

Whatever he did he must do quickly. He glanced around keenly, but could see nothing to aid him. Desperate, he looked again. Ah, yes! There, a foot or so beneath where he was standing, he saw a beam of wood projecting from the water. Jack could only see a few feet of it, for the rest of it was under water, but it was his only chance and he took it unhesitatingly. Drawing off his shoes that his feet might get a better grip, he stepped down upon it and felt his way cautiously along until he came to the broken end of the beam. Knowing that he had gained several feet, he now leaped out over the flood. As he jumped, he leaned far forward, and it was well he did, for as his feet touched the soft earth, it slid from under them and it was only by grasping at the rails that he kept himself from slipping backward into the water.

Hurrah! he was on firm ground at last, and all else was forgotten in the triumph.

Toot! Toot! T-o-o-t! It was the whistle of the express. He was just in time. He dashed up the track toward the on-coming train with the speed of an arrow. He had sore need now of all his athletic training and ran as he had never run before. There around the bend, about a fourth of a mile away, appeared the express, ten minutes behindhand, and in consequence putting on extra speed.

Jack planted himself firmly in the middle of the track and waved the red danger signal to and fro, his heart singing with joy. He expected to see the express slow down, but to his amazement it did nothing of the kind. They did not seem to see him!

What should he do? The train, with the broken trestle ahead of it, must not be allowed to take that awful plunge. He must stop it!

He waved the red flag more frantically than before, but still the train, unheeding, came on. Two minutes more and it would be upon him. Now came the supreme test of his Scout training. Would he fail?

Lightning quick he thought and decided. Springing from the track, he caught up a rock, and, as the train came abreast of him, hurled it through the window of the cab. Then, well nigh exhausted as he was, he ran along by the side of the track.