"Not a chance," he affirmed. "All these windows are protected with iron bars and nothing could get between them. Those fellows seem to have just melted away." At that instant a report rang out, and the flashlight was knocked from his hand by a bullet. "Down, fellows!" he shouted, setting the example, and the next moment all four were lying flat on the ground. They were just in time, for there was a crackling of guns, and other bullets sped over their heads. "After them, boys!" yelled Frank, leaping to his feet. "They're at the mouth of the alley. I saw the flash from their guns." He sped for the street with his comrades close upon his heels, their pistols drawn and ready for instant use. CHAPTER II WRAPPED IN MYSTERY The Army Boys looked eagerly about them when they reached the street, but could see no one. It was as though the earth had opened and swallowed the men who had sought their lives. They scattered and ran in every direction, searching all hallways and side streets for blocks around, but nothing rewarded their endeavors, and it was a bedraggled and exasperated quartette that finally came together again to compare notes and report failure. "Never saw anything like it in my life!" snorted Tom. "It's as though we were all bewitched. Somebody's wished a jinx on us. Some ghosts are putting up a job on us." "There was nothing ghostly about that bullet that knocked the flashlight out of my hand or those other bullets that came singing over our heads while we were hugging the ground," said Frank grimly. "If I don't get to the bottom of this, you can call me a Chinaman." "It gets my goat to think of those Heinies chuckling to themselves because they put one over on us," gritted Billy between his teeth. "They laugh best who laugh last," growled Bart. "They'll laugh on the other side of their mouth when we lay hands on them." "If we ever do," muttered pessimistic Tom. "But here comes our relief," he continued, as the light of a lantern hanging on the arm of the foremost man revealed a group coming toward them. "High time, too! I got drenched to the skin while I was lying on the ground in that alley." "Of course we'll have to report the whole thing to the corporal, shan't we?" inquired Bart. "I suppose we shall," Frank acquiesced, though reluctantly. "Personally, I'd like to keep the whole thing up my sleeve until we've solved the mystery. But there's danger abroad to-night, and it wouldn't be fair to the boys who are going to take our places not to put them on their guard." The corporal of the guard now had come so close that the light of his lantern fell upon the group of Army Boys. "You fellows are all here, I see," said the corporal, who was the boys' old friend, Wilson. "What was that shooting going on here? None of you hurt, I hope." "Dripping wet but right as a trivet," Frank replied with a smile, and then went on to make his report of the occurrences of the night while the corporal listened with close attention.