ear to the floor.
A faint swishing and trickling sound was perceptible from some place beneath.
'Ah!' he murmured.
Remembering that the premises almost overhung the Thames, he divined that the cellars were flooded at high tide, or that there was some kind of drain or cutting running underneath the house.
He stood up again, listening intently for any sound within the building. He thought he had detected something, and now, as he stood there alert, he heard it again-a faint scuffling, which might have been occasioned by rats or even mice, but which, in some subtle and very unpleasant way, did not suggest the movements of these familiar rodents.
Even as he perceived it, it ceased, leaving him wondering, and uncomfortably conscious of a sudden dread of his surroundings. He wondered in what part of this mysterious house Lala resided, and recognizing that his departure must leave traces, he determined to prosecute his inquiries as far as possible, since another opportunity might not arise.
He was baffled but still hopeful. Something there was in the smell of the place which threatened to unnerve him; or perhaps in its silence, which remained quite unbroken save when, by acute listening, one detected the dripping of water.
That unexplained scuffling sound, too, which he had failed to trace or identify, lingered in his memory insistently, and for some reason contained the elements of fear.
He crossed the room and began softly to mount the stair. It creaked only slightly, and the door at the top proved to be ajar. He peeped in, to find the place empty. It was a typical Chinese apartment, containing very little furniture, the raised desk being the most noticeable item, except for a small shrine which faced it on the other side of the room.
He mounted the steps to the desk and inspected a number of loose papers which lay upon it. Without exception they were written in Chinese. A sort of large, dull white blotting-pad lay upon the table, but its surface was smooth and glossy.
Over it was suspended what looked like a lampshade, but on inspection it proved to contain no lamp, but to communicate, by a sort of funnel, with the ceiling above.
At this contrivance Durham stared long and curiously, but without coming to any conclusion respecting its purpose. He might have investigated further, but he became aware of a dull and regular sound in the room behind him.
He turned in a flash, staring in the direction of two curtains draped before what he supposed to be a door.
On tiptoe he crossed and gently drew the curtains aside.
He looked into a small, cell-like room, lighted by one window, where upon a low bed Huang Chow lay sleeping peacefully!
Durham almost held his breath; then, withdrawing as quietly as he had approached, he descended the stair. At the foot his attention was again arrested by the faint scuffling sound. It ceased as suddenly as it had begun, leaving him wondering and conscious anew of a chill of apprehension.
He had already made his plans for departure, but knew that they must leave evidence, when discovered, of his visit.
A large and solid table stood near the divan, and he moved this immediately under the trap. Upon it he laid a leopard-skin to deaden any noise he might make, and then upon the leopard-skin he set a massive chair: he replaced his torch in his pocket and drew himself up on to the roof again. Reclosing the trap by means of the awl which he had screwed into it, he removed the awl and placed it in his pocket.
Then, sliding gently down the sloping roof, he dropped back into the deserted court.
VIII. A CAGE OF BIRDS
'No,' said Lala, 'we have never had robbers in the house.' She looked up at Durham naively. 'You are not a thief, are you?' she asked.
'No, I assure you I am not,' he answered, and felt himself flushing to the roots of his hair.
They were seated in a teashop patronized by the workers of the district; and as Durham, his elbows resting on the marble-topped table, looked into the dark eyes of his companion, he told himself again that whatever might be the secrets of old Huang Chow, his daughter did not share them.
The Chinaman had made no report to the authorities, although the piled up furniture beneath the skylight must have afforded conclusive evidence that a burglarious entry had been made into the premises.
'I should feel very nervous,' Durham declared, 'with all those valuables in the house.'
'I feel nervous about my father,' the girl answered in a low voice. 'His room opens out of the warehouse, but mine is shut away in another part of the building. And Ah Fu sleeps behind the office.'
'Were you not afraid when you suspected that Cohen was a burglar? You told me yourself that you did suspect him.'
'Yes, I spoke to my father about it.'
'And what did he say?'
'Oh'-she shrugged her shoulders-'he just smiled and told me not to worry.'
'And that was the last you heard about the matter?'
'Yes, until you told me he was dead.'
Again he questioned the dark eyes and again was baffled. He felt tempted, and not for the first time, to throw up the case. After all, it rested upon very slender data-the mysterious death of a Chinaman whose history was unknown and the story of a crook whose word was worth nothing.
Finally he asked himself, as he had asked himself before, what did it matter? If old Huang Chow had disposed of these people in some strange manner, they had sought to rob him. The morality of the case was complicated and obscure, and more and more he was falling under the spell of Lala's dark eyes.
But always it was his professional pride which came to the rescue. Murder had been done, whether justifiably or otherwise, and to him had been entrusted the discovery of the murderer. It seemed that failure was to be his lot, for if Lala knew anything she was a most consummate actress, and if she did not, his last hope of information was gone.
He would have liked nothing better than to be rid of the affair, provided he could throw up the case with a clear conscience. But when presently he parted from the attractive Eurasian, and watched her slim figure as, turning, she waved her hand and disappeared round a corner, he knew that rest was not for him.
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.
