He had discovered the emporium of a Shadwell live-stock dealer with whom Ah Fu had a standing order for newly fledged birds of all descriptions. Purchases apparently were always made after dusk, and Ah Fu with his birdcage was due that evening.

A scheme having suggested itself to Durham, he now proceeded to put it into execution, so that when dusk came, and Ah Fu, carrying an empty birdcage, set out from the house of Huang Chow, a very dirty-looking loafer passed the corner of the street at about the time that the Chinaman came slinking out.

Durham had mentally calculated that Ah Fu would be gone about half an hour upon his mysterious errand, but the Chinaman travelled faster than he had calculated.

Just as he was about to climb up once more on to the sloping roof, he heard the pattering footsteps returning to the courtyard, although rather less than twenty minutes had elapsed since the man had set out.

Durham darted round the corner and waited until he heard the door closed; then, returning, he scrambled up on to the roof, creeping forward until he was lying looking down through the skylight into the darkened room below.

For ten minutes or more he waited, until he began to feel cramped and uncomfortable. Then that happened which he had hoped and anticipated would happen. The place beneath became illuminated, not fully, by means of the hanging lamps, but dimly so that distorted shadows were cast about the floor. Someone had entered carrying a lantern.

Durham's view-point limited his area of vision, but presently, as the light came nearer and nearer, he discerned Ah Fu, carrying a lantern in one hand and a birdcage in the other. He could hear nothing, for the trap fitted well and the glass was thick. Moreover, it was very dirty. He was afraid, however, to attempt to clean a space.

Ah Fu apparently had set the lantern upon a table, and into the radius of its light there presently moved a stooping figure. Durham recognized Huang Chow, and felt his heart beats increasing in rapidity.

Clutching the framework of the trap with his hands, he moved his head cautiously, so that presently he was enabled to see the two Chinamen. They were standing beside the lacquered coffin upon its dragon-legged pedestal. Durham stifled an exclamation.

One end of the ornate sarcophagus had been opened in some way!