n the fifth story of a house, bound, helpless, I knew, too, that a
second mystic guardian of the slipper was come to accomplish the
task in which the first had failed!

I began to pray fervently.

Neither of the windows were closed; and now through the intense
darkness I heard one of them being raised up--up--up...

The sacking was pulled aside inch by inch.

Silhouetted against the faintly luminous background I saw a hunched,
unnatural figure. The real was more dreadful even than the
imaginary--for some stray beam of light touched into cold radiance
a huge curved knife which the visitant held between his teeth!

My fear became a madness, and I twisted my body violently in a wild
endeavour to free myself. A dreadful pain shot through my left
shoulder, and the whole nightmare scene--the thing with the knife
at the window--the low-ceiled room-began to fade away from me. I
seemed to be falling into deep water.

A splintering crash and the sound of shouting formed my last
recollections ere unconsciousness came.

I found myself lying in an armchair with Bristol forcing brandy
between my lips. My left arm hung limply at my side and the pain
in my dislocated shoulder was excruciating.

"Thank God you are all right, Mr. Cavanagh!" said the inspector.
"I got the surprise of my life when we smashed the door in and
found you tied up here!"

"You came none too soon," I said feebly. "God knows how Providence
directed you here."

"Providence it was," replied Bristol. "From the roof of Wyatt's
Buildings--you know the spot?--I saw the second yellow devil
coming. By God! They meant to have it to-night! They don't value
their lives a brass farthing against that damned slipper!"

"But how--"

"Along the telegraph-wires, Mr. Cavanagh! They cross Wyatt's
Buildings and cross this house. It was a moonless night or we
should have seen it at once! I watched him, saw him drop to this
roof--and brought the men around to the front."

"Did he, that awful thing, escape?"

"He dropped full forty feet into a tree--from the tree to the
ground, and went off like a cat!"

"Earl Dexter has escaped us," I said, "and he has the slipper!"

"God help him!" replied Bristol. "For by now he has that hell-pack
at his heels! What a case! Heavens above, it will drive me mad!"

CHAPTER XIX

A RAPPING AT MIDNIGHT

Inspector Bristol finished his whisky at a gulp and stood up, a tall,
massive figure, stretching himself a