wide, carpeted stairs. Next he turned his attention to the lacquered
coffin which occupied the corresponding recess to that filled by the
couch. It was an extraordinarily ornate piece of lacquer work and
probably of great value.

The lid appeared to be screwed on, and Durham stood staring at the
thing, half revolted and half fascinated. He failed to discover any
means of opening it, however, and when he tried to move it bodily found
it very heavy. He came to the conclusion that all the portable valuables
were contained in locked cases or cabinets, and out of this discovery
grew an idea.

The case containing the snuff bottles stood too close to the wall to
enable him to test his new theory, but a square case near the office
door, in which were five of six small but almost priceless pieces of
porcelain, afforded the very evidence for which he was looking.

Thin electric flex descended from somewhere inside the case down one
of the legs of the pedestal, and through a neatly drilled hole in the
floor, evidently placed there to accommodate it.

"Burglar alarm!" he muttered.

The opening of this case, and doubtless of any of the others, would
set alarm bells ringing. This was not an unimportant discovery, but it
brought him very little nearer to a solution of the chief problem which
engaged his mind. Assuming that Cohen had opened one of the cases and
had alarmed old Huang Chow, what steps had the latter taken to deal with
the intruder which had resulted in so ghastly a death? And how had he
disposed of the body?

As Durham stood there musing and looking down through the plate-glass at
the delicate porcelain beneath, a faint sound intruded itself upon the
stillness. It gave him another idea. Part of the floor was stone-paved,
but part was wood.

Upon a portion of the latter, where no carpet rested, Durham dropped
flat, pressing his 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 unpleasa