Cautiously, and with his revolver ready for instant action, Sergeant Archer, accompanied by two of the crew, descended into a dug-out, the entrance of which was not blocked sufficiently to prevent squeezing through. Within were half a dozen dead Huns--killed instantly by the concussion of a high-explosive shell, yet without a wound on them. Apparently, the dug-out formed the engineers' store, for there were tools in plenty, including mattocks, spades, sectional ladders, and ropes. Returning with his find, the sergeant was about to report upon his success when a bomb hurtled through the air. Instantly the three men threw themselves flat on their faces, while a second later the missile exploded without doing them harm beyond covering them with mud and dust. Starting to his feet, Archer levelled his revolver. He was at a loss to discover the whereabouts of the thrower. It seemed as if the missile had been projected from the Tank, until a burst of machine-gun fire leapt from her side into the wall of earth within three feet from the muzzle of the gun. The landship had come to a stop immediately opposite the mouth of a dug-out which had been so badly battered that the timber props were leaning together like an inverted V. Within a desperate Hun still lurked, and finding Archer and the two men in the open he had hurled a bomb in the hope of strafing the Englishmen. "Hands up!" shouted Archer, flattening himself against the bank of earth by the entrance of the dug-out and firing a couple of shots into the cavernous recess by way of adding weight to his words. There was no reply. "That Maxim laid the blighter out, sergeant," suggested one of the men. "I won't chance my arm on that," declared Archer. "Hand me that spade." Removing his steel helmet, the non-com. placed it on the handle of the spade and thrust it carefully in front of the partly blocked tunnel. Again there was no response to the silent invitation. Archer repeated the tactics, this time exposing a little more of his metal head-dress. A rifle-shot rang out. The helmet was completely perforated by the bullet. "All right, Fritz," exclaimed the sergeant. "If you won't give in like a sensible fellow we'll have to rout you out. I've a smoke-bomb ready." "Is that an English officer who speaks?" enquired the lurking German. "A British sergeant--quite good enough for a Boche to argue with," retorted Archer. "So you speak English? Come out and surrender. That's plain enough, and you know it." "What's happening, sergeant?" asked Setley, who, screened by the immense bulk of his Tank from the Hun's lair, had been conversing with Danvers. "There's a Boche in this dug-out, sir," reported the non-com. "Be careful, sir; he chucked a bomb out just now. I believe he's an officer, because he enquired if he was chewing his rag to a British officer." "I officer am," interposed the unseen. "To you I make surrender." "Right-o," replied Ralph. "Out you come."