"Oh, you're only a boy and don't understand the trick," growled the lieutenant, who was in a bad humor generally. "I don't see why they let you come along." "Our boat is doing about as well as any of them," answered Larry, bound to defend himself. "Two boats are aground to our left and three behind us." "See here, don't talk back to me! You tend to business and keep us out of the mud," roared the lieutenant, in worse humor than before. An angry retort arose to Larry's lips, but he checked it. "A quarrel won't do any good," he thought. "But what a bulldog that fellow is--as bad as Quartermaster Yarrow, who caused me so much trouble on the trip out here." On went the cascos once more, around a tortuous bend and past a bank fringed with bushes and reeds. The mosquitoes were numerous, likewise the flies, and everybody began to wish the journey at an end. "We'd better make a charge on the insects," growled one old soldier. "They are worse nor the rebels ten times over," and, just then, many were inclined to agree with him. Tobacco was scarce or smoking would have been far more plentiful than it was. Midnight came and went, and found the expedition still some distance from the lake. A few of the soldiers were sleeping, but the majority remained wide awake, fighting off the marshland pests, and aiding in keeping the cascos and launches from running high and dry in the mud. Had it not been for the tinclads it is doubtful if the Laguna de Bay would have been gained at all by more than half of the craft composing the turnout. But they came to the rescue time and again, and so the expedition crawled along, until, at four o'clock, the clear sheet of water beyond was sighted. They were making the last turn before the lake was gained when the casco ahead of that steered by Larry went aground once more, dragging Larry's craft behind it. The youth did all he could to back water, but in vain, and once more they heard the unwelcome slish of mud under their bottom. "Now you've done it again!" howled the lieutenant, leaping up from his seat. "You numskull! give me that oar." And he tried to wrench the blade from Larry's hand. "It was not my fault," began the youth, when the officer forced the blade from him and hurled him back on one of the soldiers. Then the lieutenant tried to do some poling for himself, and got the oar stuck so tightly in the mud that he could not loosen it. Burning with indignation, Larry felt himself go down in a heap, and at once tried to get up again. At the same time the soldier beneath him gave him a shove which pitched him several feet forward. He landed up against the lieutenant with considerable force, and in a twinkle the officer went overboard, head first, into the water and mud where the casco had stuck fast. CHAPTER IV THE GAP IN THE FIRING LINE "Hullo, Lieutenant Horitz has fallen overboard!" "Pull him out of the mud, before he smothers or drowns!"