"I got the picture," he clipped, "but we're going to have to work fast. The police probably are on their way here now. Vance caught me in the act of stealing the painting." He still was panting from the exertion of his race here. "Then clip it to this frame quickly!" The professor indicated an arrangement like an oversize drawing board. He hurried to assist the younger man. In a moment their work was done. There, at last, was "Elaine Duchard's Escape." Mark for the first time studied it carefully. * * * * * Four people were shown. The central figure was that of the first Elaine Duchard. She was in the act of entering a carriage, her lovely face alive with panic. Beside her a young man--his face in the shadows--held a horse pistol on another man. This second man's features were twisted with hate; Mark thought he never had seen such malevolent eyes. "Baron Morriere" the professor explained. "The younger man is Jacques Rombeau, Elaine Duchard's lover." Mark nodded. Turned to scrutinize a third man, unidentifiable, who was clambering to the driver's seat of the coach. The next instant the laboratory was re-echoing with the sound of heavy blows upon the door. "Open up!" roared a muffled voice. "It's the law!" "The police!" Mark's face went pale. Professor Duchard darted to the bench which lined one wall. Seized a strange-looking helmet which stood there. Rushed with it to Mark. "The insulator-helmet!" he explained hastily, his blue eyes feverish with excitement. "Strap it on! Quickly!" "Open up!" the alien voice roared again. "We want in!" And then the angry accents of Adrian Vance: "Break it down, officer! Don't let them get away!" Mark hauled the frame on which the painting was stretched to a position in front of the mirror. Whirled back. Gripped his companion's hand. "Will it work, professor? Will the mirror take me back through time?" "That I cannot tell you, my boy. But it should. You know the formula I worked out. You understand the process by which it was constructed." A second's pause. "Actually, I believe it should work far better than the previous time mirror. The one Vance gave Elaine was very old, very crude. This one is the product of modern science, modern workmanship. It creates a tremendously larger rift in the space-time continuum--" A shot rang out. At the other end of the laboratory, the outside door burst open, lock shattered. Uniformed police rushed in, Adrian Vance at their head. "Mark! Quickly! I shall hold them!" With a savage jerk, Elaine's fiance ripped aside the cloth that veiled the new time mirror. The reflection of Jerbette's painting sprang across its silver surface. Mark's jaw went hard with tension. He glued his eyes to the figure of Jacques Rombeau, Elaine Duchard's lover. Behind him, Adrian Vance charged down the laboratory, struggling to shake off the frail, tenacious figure of Professor Duchard. He brought up his heavy Magnum.