It was at this very moment that old Huang Chow, asleep in his cell-like apartment, was aroused by the tinkling of a bell set immediately above his head. He awoke instantly, raised his hand and stopped the bell. His expression, could anyone have been present to see it, was a thing unpleasant to behold. Triumph was in it, and cunning cruelty. His long yellow fingers reached out for his hornrimmed spectacles which lay upon a little table beside him. Adjusting them, he pulled the curtains aside and shuffled silently across the large room. Mounting the steps to the raised writing-table, he rested his elbows upon it, and peered down at that curious blotting-pad which had so provoked the curiosity of Durham. Could Durham have seen it now the mystery must have been solved. It was an ingenious camera obscura apparatus, and dimly depicted upon its surface appeared a reproduction of part of the storehouse beneath! The part of it which was visible was that touched by the light of an electric torch, carried by a man crossing the floor in the direction of the lacquered coffin upon the gilded pedestal! Old Huang Chow chuckled silently, and his yellow fingers clutched the table edge as he moved to peer more closely into the picture. “Poor fool!” he whispered in Chinese. “Poor fool!” It was the man who had come with the introduction from Mr. Isaacs--a new impostor who sought to rob him, who sought to obtain information from his daughter, who had examined his premises last night, and had even penetrated upstairs, so that he, old Huang Chow, had been compelled to disconnect the apparatus and to feign sleep under the scrutiny of the intruder. To-night it would be otherwise. To-night it would be otherwise. X THE LACQUERED COFFIN Durham gently raised the trap in the roof of Huang Chow's treasure-house. He was prepared for snares and pitfalls. No sane man, on the evidence which he, Durham, had been compelled to leave behind, would have neglected to fasten the skylight which so obviously afforded a means of entrance into his premises. Therefore, he was expected to return. The devilish mechanism was set ready to receive him. But the artist within him demanded that he should unmask the mystery with his own hands. Moreover, he doubted that an official visit, even now, would yield any results. Old Huang Chow was too cunning for that. If he was to learn how the man Cohen had died, he must follow the same path to the bitter end. But there were men on duty round the house, and he believed that he had placed them so secretly as to deceive even this master of cunning with whom he was dealing. He repeated his exploit, dropping with a dull thud upon the cushioned divan. Then, having lain there listening awhile, he pressed the button of his torch, and, standing up, crept across the room in the direction of the stairway.