"Zig-zag, Chester!" cried Hal, and suited the action to the word. Chester followed his chum’s example and the first volley from behind failed to find a mark. By this time the lads were at the edge of the trench. "Up and over with you, quick!" cried Chester. Hal leaped to the top of the trench and toppled to the ground beyond even as half a score of bullets sang across the spot where his head had been a moment before. Chester also sprang for the top of the trench. But he had leaped too soon, and instead of reaching the top he fell short, and dropped down inside the trench again. Germans were almost upon him when he regained his feet. Chester realized that a second leap was out of the question at the minute, so guns in hand he turned and faced his foes. "Crack! Crack! Crack! Crack!" His automatics spoke angrily and all four bullets found human targets. Hal, meanwhile, safely over the trench, looked around for Chester. When he failed to see him he realized on the instant what had happened. "What shall I do?" he asked himself. "Duty says to hurry to a place of safety, but friendship says help Chester." He wasted little time in thought. He scrambled back to the top of the earthen embankment and took in the sight about him. There Chester stood at bay, his automatics held in steady hands. Hal drew his own weapons. "Jump up here quick, Chester!" he called. "I’ll cover you." "Don’t bother about me," Chester called back. "Get away from here. Remember you must get through. I’ll hold ’em off." "Don’t be a fool," shouted Hal, discharging his revolver at a big German who was about to shoot Chester down with his rifle. "Come up here." Chester paid no further heed to his chum. Hal gritted his teeth, dropped one revolver in his pocket, and reaching down grasped Chester by the shoulder. "Come on," he called. Chester shook off his chum’s hand. "Let me alone." he shouted angrily. "I’ll get a few of these boches before they down me." His revolvers spoke as he talked, and two Germans dropped. Meanwhile bullets were striking on all sides of the two lads, and it seemed a miracle that they were not touched. Hal considered the situation in a flash. "There’s one chance," he said. Deliberately he sheathed his other revolver, thus leaving himself unarmed in the face of his foes. Then, bracing himself as best he could on the embankment, he reached down and seized Chester by both shoulders. Putting forth all his strength, Hal heaved mightily, and drew his chum to the top of the embankment with him. There he released him and drew his revolvers again. Came a cry of rage from inside the trench as the Germans saw their prey about to escape. Two men dropped on their knees and sighted their rifles carefully. But before they could fire Hal had accounted for one and Chester for the other. Again a howl of rage went up from the German trench.