Apparently secure in the belief that the forts at Duala could successfully ward off the attacks of any enemy, the German commander at Boak had grown careless, and the lads could not see a single sign of soldiers or sentries. Frank glanced behind him and ordered softly: "Take down all flags!" The command was passed from one boat to another, and soon the little flotilla was moving up the river, looking more like a pleasure party than a hostile force, except for the uniforms of the men. However, these could not be plainly seen from the village, because of the shadow cast by the dense foliage that overhung the river. Now, through their glasses, the boys could see several German officers peering at them through long telescopes. "They've seen us," said Jack. "Yes," was Frank's reply. "But evidently they believe us friends, or they would open fire on us." "Perhaps their guns are not of the heavy caliber of those at Duala." "By Jove! I believe you have hit it!" exclaimed Frank. "In that case, with our rapid-firers, we should have little trouble taking the village." At the point where the stream widened out, Jack allowed two of the craft behind to come up even and thus, three abreast, the journey was continued. Every man was now at his post. The gunners were ready to open with the rapid-firers at a moment's notice. All held their rifles ready. Still the Germans did not fire, apparently uncertain of the identity of the newcomers--or rather, seemingly certain they were friends. Suddenly a squad of six German soldiers wheeled a small, old-fashioned cannon to the landing near the officers, and a moment later a solid shot plowed up the water in front of the first boat of the British flotilla. "A signal to show our colors," said Jack grimly. "What do you say, Frank? Are we ready to show them?"' "Yes!" cried Frank. An instant and the English Jack floated over each boat, while at the same time the first three boats in the battle line opened with their rapid-firers. At the distance, scarcely two hundred yards, the execution was terrible. The German officers and the entire gun squad, riddled with bullets, fell forward on their faces. But this was only the beginning. Swiftly moving German troops now came marching to the river front, steadily, in spite of the withering British fire, and sternly, to repel the foe. Slowly they came into position, and, dropping on their knees, poured a volley into the little flotilla. But, deadly as this fire was, that of the rapid-firers aboard the boats was more so. The British did not escape without considerable damage, but the German loss was far heavier. Steadily, in spite of the grilling German fire, the boats pressed on. Each man concealed himself as well as he could behind the low sides of the boats, exposing just enough of his head to take aim at the enemy.