someone in connection with
so small a box) had been concealed inside, and had killed Professor
Deeping whilst he was actually engaged in endeavouring to force it
open. This inconceivable creature had then searched the study for
the slipper--or for the key of the safe. Interrupted and trapped
by the arrival of the police, the creature had returned to the box,
re-closed it, and had actually been there when the study was
searched!

For a creature so small as the murderous thing in the box to slip
out during the confusion, and at some time prior to Bristol's
arrival, was no difficult matter. The inspector and I were certain
that these were the facts.

But what was this creature?

I turned to the chapter in "Assyrian Mythology"--"The Tradition
of the Hashishin."

The legends which the late Professor Deeping had collected relative
to this sect of religious murderers were truly extraordinary. Of
the cult's extinction at the time of writing he was clearly certain,
but he referred to the popular belief, or Moslem legend, that, since
Hassan of Khorassan, there had always been a Sheikh-al-jebal, and
that a dreadful being known as Hassan of Aleppo was the present
holder of the title.

He referred to the fact that De Sacy has shown the word Assassin
to be derived from Hashishin, and quoted El-Idrisi to the same
end. The Hashishin performed their murderous feats under the
influence of hashish, or Indian hemp; and during the state of
ecstasy so induced, according to Deeping, they acquired powers
almost superhuman. I read how they could scale sheer precipices,
pass fearlessly along narrow ledges which would scarce afford
foothold for a rat, cast themselves from great heights unscathed,
and track one marked for death in such a manner as to remain unseen
not only by the victim but by others about him. At this point of
my studies I started, in a sudden nervous panic, and laid my hand
upon my revolver.

I thought of the eyes which had seemed to look up from the black
well of the staircase--I thought of the horrible end of this man
whose book lay upon the table ... and I thought I heard a faint
sound outside my study door!

The key of Deeping's safe, and his letter to me, lay close by my
hand. I slipped them into a drawer and locked it. With every
nerve, it seemed, strung up almost to snapping point, I mechanically
pursued my reading.

"At the time of the Crusades," wrote Deeping, "there was a story
current of this aw