de is ten
inches long, two inches broad at the base, and tapering to a rounded but
sharp point, rather peculiar. It is double-edged.

"The metal sheath is curious for having a crosspiece, which, taken with
the fact that the sheath itself is continued three parts up the hilt of
the dagger (in a most inconvenient fashion), gives it the appearance of a
cross. That this is not unintentional is shown by an engraving of the
Christ crucified upon one side, whilst upon the other, in Latin, is the
inscription: 'Vengeance is Mine, I will Repay.' A quaint and rather
terrible conjunction of ideas. Upon the blade of the dagger is graven in
old English capitals: I WATCH. I STRIKE. On the butt of the hilt there is
carved deeply a Pentacle.

"This is a pretty accurate description of the peculiar old weapon that
has had the curious and uncomfortable reputation of being able (either of
its own accord or in the hand of something invisible) to strike
murderously any enemy of the Jarnock family who may chance to enter the
Chapel after nightfall. I may tell you here and now, that before I left,
I had very good reason to put certain doubts behind me; for I tested the
deadliness of the thing myself.

"As you know, however, at this point of my investigation, I was still at
that stage where I considered the existence of a supernatural Force
unproven. In the meanwhile, I treated the Chapel drastically, sounding
and scrutinizing the walls and floor, dealing with them almost foot by
foot, and particularly examining the two tombs.

"At the end of this search, I had in a ladder, and made a close survey of
the groined roof. I passed three days in this fashion, and by the evening
of the third day I had proved to my entire satisfaction that there is no
place in the whole of that Chapel where any living being could have
hidden, and also that the only way of ingress and egress to and from the
Chapel is through the doorway which leads into the castle, the door of
which was always kept locked, and the key kept by Sir Alfred Jarnock
himself, as I have told you. I mean, of course, that this doorway is the
only entrance practicable to material people.

"Yes, as you will see, even had I discovered some other opening, secret
or otherwise, it would not have helped at all to explain the mystery of
the incredible attack, in a normal fashion. For the butler, as you know,
was struck in full sight of the Rector, Sir Jarnock and his son. And old
Bellett himself kn