She thrust the keys into the hand of Inspector Kelly, pointing to one of them, and: "That is the key!" she said. "Have your pistol ready. Do not touch anything in the room and do not go in if I tell you not to. Come!" They pressed along the passage, came to the stair and were about to ascend, when there ensued a dull reverberating boom, and Miska shrank back into Stuart's arms with a stifled shriek. "Oh! Chunda Lal!" she moaned--"Chunda Lal! It is the trap!" "The trap!" said Inspector Kelly. "The cellar trap. He has thrown him down ... to the ants!" Inspector Kelly uttered a short laugh; but Stuart repressed a shudder. He was never likely to forget the skeleton of the Nubian mute which had been stripped by the ants in sixty-nine minutes! "We are too late!" whispered Miska. "Oh! listen! listen!" Bells began to ring somewhere above them. "Max and Dunbar are in!" said Kelly. "Come on, sir! Follow closely, boys!" He ran up the stairs and along the corridor to the door at the end. A muffled shot sounded from somewhere in the depths of the house. "That's Harvey!" said one of the men who followed--"Our man must have tried to escape by the tunnel to the river bank!" Inspector Kelly placed the key in the lock of the door. It was at this moment that Gaston Max, climbing up to the front balcony by means of the natural ladder afforded by the ancient ivy, grasped the iron railing and drew himself up to the level of the room. By this same stairway Chunda Lal had ascended to death and Miska had climbed down to life. "Mind the ironwork doesn't give way, sir!" called Dunbar from below. "It is strong," replied Max. "Join me here, my friend." Max, taking a magazine pistol from his pocket, stepped warily over the ledge into the mysterious half-light behind the great screen. As he did so, one of the lacquer doors was unlocked from the outside, and across the extraordinary, smoke-laden room he saw Inspector Kelly enter. He saw something else. Seated in a strangely-shaped canopied chair was a figure wearing a rich mandarin robe, but having its face covered with a green veil. _"Mon Deiu!_ at last!" he cried, and leapt into the room. "'The Scorpion'!" Even as he leapt, and as the Scotland Yard men closed in upon the chair also, all of them armed and all half fearful, a thing happened which struck awe to every heart--for it seemed to be supernatural. Raising a metal hammer which he held in his hand, Fo-Hi struck the bronze bell hung beside the chair. It emitted a deep, loud note.... There came a flash of blinding light, and intense crackling sound, the crash of broken glass, and a dense cloud of pungent fumes rose in the heated air. Dunbar had just climbed in behind Gaston Max. Bother were all but hurled from their feet by the force of the explosion. Then: "Oh, my God!" cried Dunbar, staggering, half blinded, _"look--look!"_