him--a terror akin to that which children experience
in the darkness. But he yet had a fair mastery of his emotions;
when--not suddenly, as is the way of a failing electric lamp--but
slowly, uncannily, unnaturally, the table-lamp became extinguished!

Darkness.... Cairn turned towards the window. This was a moonless
night, and little enough illumination entered the room from the court.

Three resounding raps were struck upon the door.

At that, terror had no darker meaning for Cairn; he had plumbed its
ultimate deeps; and now, like a diver, he arose again to the surface.

Heedless of the darkness, of the seemingly supernatural means by which
it had been occasioned, he threw open the door and thrust his revolver
out into the corridor.

For terrors, he had been prepared--for some gruesome shape such as we
read of in _The Magus_. But there was nothing. Instinctively he had
looked straight ahead of him, as one looks who expects to encounter a
human enemy. But the hall-way was empty. A dim light, finding access
over the door from the stair, prevailed there, yet, it was sufficient
to have revealed the presence of anyone or anything, had anyone or
anything been present.

Cairn stepped out from the room and was about to walk to the outer
door. The idea of flight was strong upon him, for no man can fight the
invisible; when, on a level with his eyes--flat against the wall, as
though someone crouched there--he saw two white hands!

They were slim hands, like the hands of a woman, and, upon one of the
tapered fingers, there dully gleamed a green stone.

A peal of laughter came chokingly from his lips; he knew that his
reason was tottering. For these two white hands which now moved along
the wall, as though they were sidling to the room which Cairn had just
quitted, were attached to no visible body; just two ivory hands were
there ... _and nothing more_!

That he was in deadly peril, Cairn realised fully. His complete
subjection by the will-force of Ferrara had been interrupted by the
ringing of the telephone bell But now, the attack had been renewed!

The hands vanished.

Too well he remembered the ghastly details attendant upon the death of
Sir Michael Ferrara to doubt that these slim hands were directed upon
murderous business.

A soft swishing sound reached him. Something upon the writing-table
had been moved.

The strangling cord!

Whilst speaking to his father he had taken it out from the drawer, and
when he