the 'water circle.' And
now I had my first protective barrier complete.

"Now, anyone, except you who know something of my methods of
investigation, might consider all this a piece of useless and foolish
superstition; but you all remember the Black Veil case, in which I
believe my life was saved by a very similar form of protection, whilst
Aster, who sneered at it, and would not come inside, died. I got the idea
from the Sigsand MS., written, so far as I can make out, in the 14th
century. At first, naturally, I imagined it was just an expression of
the superstition of his time; and it was not until a year later that it
occurred to me to test his 'Defense,' which I did, as I've just said, in
that horrible Black Veil business. You know how _that_ turned out. Later,
I used it several times, and always I came through safe, until that
Moving Fur case. It was only a partial 'defense' therefore, and I nearly
died in the pentacle. After that I came across Professor Garder's
'Experiments with a Medium.' When they surrounded the Medium with a
current, in vacuum, he lost his power--almost as if it cut him off from
the Immaterial. That made me think a lot; and that is how I came to make
the Electric Pentacle, which is a most marvelous 'Defense' against
certain manifestations. I used the shape of the defensive star for this
protection, because I have, personally, no doubt at all but that there is
some extraordinary virtue in the old magic figure. Curious thing for a
Twentieth Century man to admit, is it not? But, then, as you all know, I
never did, and never will, allow myself to be blinded by the little cheap
laughter. I ask questions, and keep my eyes open.

"In this last case I had little doubt that I had run up against a
supernatural monster, and I meant to take every possible care; for the
danger is abominable.

"I turned-to now to fit the Electric Pentacle, setting it so that each of
its 'points' and 'vales' coincided exactly with the 'points' and 'vales'
of the drawn pentagram upon the floor. Then I connected up the battery,
and the next instant the pale blue glare from the intertwining vacuum
tubes shone out.

"I glanced about me then, with something of a sigh of relief, and
realized suddenly that the dusk was upon me, for the window was grey and
unfriendly. Then 'round at the big, empty room, over the double barrier
of electric and candle light. I had an abrupt, extraordinary sense of
weirdness thrust upon me--in the ai