I experienced a
momentary, half-aware sense of a faint, peculiar, disagreeable odor in
the passage; but it was not until the following night that I _realized_ I
had noticed a smell that offended me. You follow me? It is so often like
that--one suddenly knows a thing that really recorded itself on one's
consciousness, perhaps a year before.

"The next morning at breakfast, I mentioned casually to my mother that
she had 'dropped off,' and I had shut the door for her. To my surprise,
she assured me she had never been out of her room. I reminded her about
the two raps she had given upon the banister; but she still was certain I
must be mistaken; and in the end I teased her, saying she had grown so
accustomed to my bad habit of sitting up late, that she had come to call
me in her sleep. Of course, she denied this, and I let the matter drop;
but I was more than a little puzzled, and did not know whether to believe
my own explanation, or to take the mater's, which was to put the noises
down to the mice, and the open door to the fact that she couldn't have
properly latched it, when she went to bed. I suppose, away in the
subconscious part of me, I had a stirring of less reasonable thoughts;
but certainly, I had no real uneasiness at that time.

"The next night there came a further development. About two thirty a.m.,
I heard my mother's door open, just as on the previous night, and
immediately afterward she rapped sharply, on the banister, as it seemed
to me. I stopped my work and called up that I would not be long. As she
made no reply, and I did not hear her go back to bed, I had a quick sense
of wonder whether she might not be doing it in her sleep, after all, just
as I had said.

"With the thought, I stood up, and taking the lamp from the table, began
to go toward the door, which was open into the passage. It was then I got
a sudden nasty sort of thrill; for it came to me, all at once, that my
mother never knocked, when I sat up too late; she always called. You will
understand I was not really frightened in any way; only vaguely uneasy,
and pretty sure she must really be doing the thing in her sleep.

"I went quickly up the stairs, and when I came to the top, my mother was
not there; but her door was open. I had a bewildered sense though
believing she must have gone quietly back to bed, without my hearing
her. I entered her room and found her sleeping quietly and naturally; for
the vague sense of trouble in me was suffic