The boys needed no urging, for the sounds told them that their foe had almost reached the bank of the canal. They bent to the oars and the boat shot away from the shore. But they had scarcely taken three strokes before a star shell rose from the enemy side of the canal and shed a greenish ghastly radiance over the scene. By its light, they saw a dozen or more Germans on the bank they had just left, and a volley of bullets that came singing over their heads and about the boat told them that they offered a good target. But it was not this group of enemies that gave them the greatest concern. A more serious peril threatened them. For in that green flare of the star shell they saw two boats between them and the shore they sought. And the guttural shouts that had come from these boats at their discovery told the Americans that the occupants were Germans. They grasped the situation at once. These were the boats whose oar strokes had been heard by Tom. There were half a dozen men in each boat and their errand on the American side had been the same as that of the Army Boys among the Germans. It was a time for quick thinking, and the corporal was equal to the emergency. His party was outnumbered three to one by the men in the enemy boats, to say nothing of their comrades on the farther shore. The first star shell had faded, but others followed in quick succession, so that there was no chance to slip between the enemy boats in the darkness. “Turn her head upstream,” ordered Wilson, and the boat swung round. “Now, pull for your lives,” the corporal commanded. “Our only chance is to get far enough ahead of those fellows to cut into the shore. When you fellows are tired, Waldon and I will take the oars. Pull, now, pull!” Frank and Tom obeyed, putting every ounce of strength into their strokes, until it seemed as though the oars must snap. The boat sprang forward like a live thing, while the corporal and Billy, with their bodies concealed as much as possible, sent shot after shot from their revolvers at the men in the German boats. The enemy had grasped the purpose of the turning upstream, and both boats raced on, trying to keep on a line with the Americans and prevent them turning in to shore. At the same time, the German patrol on the further bank ran along the shore with a constant crackling of rifle fire. Bullets whistled about the boat, some of them penetrating the side. One of them went through the corporal’s sleeve, grazing his arm and bringing blood. Another knocked Tom’s oar from his hand, but he recovered it in a desperate grab before it got out of reach, and the boat kept on with only a momentary lessening of its speed. Suddenly Billy gave an exclamation of alarm as a dark wall of what appeared to be solid rock loomed up before them. “Back water!” he shouted. “The boat will be smashed!”