morse, or even fear, in his
looks."

"Of course not. You are looking at the reflection of one of my men. Miss
Van Arsdale, do you recognize the place now under your eye?"

"I do not. You spoke of an arch in the hall, at the left of the carriage
entrance, and I see an arch in the window-pane before me, but--"

"You are looking straight through the alcove,--perhaps you did not
know that another door opened at its back,--into the passage which runs
behind it. Farther on is the arch, and beyond that arch the side hall
and staircase leading to the dressing-rooms. This door, the one in the
rear of the alcove, I mean, is hidden from those entering from the main
hall by draperies which have been hung over it for this occasion, but
it is quite visible from the back passageway, and there can be no doubt
that it was by its means the man, whose reflected image you saw, both
entered and left the alcove. It is an important fact to establish, and
we feel very much obliged to you for the aid you have given us in this
matter."

Then, as I continued to stare at him in my elation and surprise, he
added, in quick explanation:

"The lights in the alcove, and in the several parlors, are all hung with
shades, as you must perceive, but the one in the hall, beyond the arch,
is very bright, which accounts for the distinctness of this double
reflection. Another thing,--and it is a very interesting point,--it
would have been impossible for this reflection to be noticeable
from where you sit, if the level of the alcove flooring had not been
considerably higher than that of the main floor. But for this freak of
the architect, the continual passing to and fro of people would have
prevented the reflection in its passage from surface to surface. Miss
Van Arsdale, it would seem that by one of those chances which happen
but once or twice in a lifetime, every condition was propitious at the
moment to make this reflection a possible occurrence, even the location
and width of the several doorways and the exact point at which the
portiere was drawn aside from the entrance to the alcove."

"It is wonderful," I cried, "wonderful!" Then, to his astonishment,
perhaps, I asked if there was not a small door of communication between
the passageway back of the alcove and the large central hall.

"Yes," he replied. "It opens just beyond the fireplace. Three small
steps lead to it."

"I thought so," I murmured, but more to myself than to him. In my mind I
wa