The sentry idly watched the supposed workman, who slouched along gazing at the ground in front of him in the most stolid fashion. Just as he was on the point of passing the sentry, however, he shot out a hand, seized the man's rifle, and tore it from his grasp. Simultaneously a hand appeared from behind, and a cloth was clapped over the soldier's nose and mouth and held firmly in position, while another hand and arm grasped him round the middle. [Illustration: A CLOTH WAS CLAPPED OVER THE SOLDIER'S NOSE AND MOUTH] Noiselessly grounding the captured rifle, Max in his turn sprang upon the sentry and wound both his arms about him, crushing his arms to his side and preparing to subdue his wildest struggles. Almost immediately, however, the man's muscles relaxed, as the chloroform, with which the cloth had been sprinkled, took effect, and Max and Dale lowered him to the ground. "Now, Dale, off with his tunic and helmet and put them on," cried Max rapidly. "Then take his rifle and stand on guard. All is well, and I believe we shall win through without a hitch." Dale did as he was bidden. The soldier's tunic and helmet were removed, and his body was dragged into the shadow close to the wall of the building. Then Max walked quickly back to the spot where the shells had been deposited. Here Dubec crouched in readiness. "Bring them along," whispered Max. "The sentry is disposed of, and we ought to meet with no interruption." "'Twas splendidly done," replied Dubec with enthusiasm. "The man seemed to be overcome as though by magic, and I heard scarce a sound." In three trips the shells were transported to the power-house and laid along the wall. Then Max went to one of the windows and looked in. The power-house was largely underground, and the windows, which ran around all sides on a level with the ground at intervals of about six feet, were high above the great boilers. In fact, as Max gazed down he had a bird's-eye view of the interior, and could see workmen flitting to and fro, stoking the great furnaces in blissful ignorance of the fact that a bolt which might destroy them with their engines was on the point of being shot. Drawing back his head, Max drew a bomb of his own manufacture from his pocket and lit the fuse. Then he leaned through the window, and, shading his mouth with his hands so that his words might carry downwards and be heard above the roar of the engines, cried in quick, urgent, warning tones: "Fly for your lives--the engine-house is being blown up! Fly! fly! fly!" The workmen looked up, startled, and into their midst Max flung his bomb. The men scattered to right and left, and a second or two later it burst with a splutter, sending out a great puff of white, pungent smoke. It was quite harmless, but the men did not know that, and a great cry of alarm went up and a terrific stampede began towards the nearest exit.