risp
sound of boots upon gravel. The steps passed along the path on
the other side of the wall under which I crouched. Looking over,
I saw the naturalist pause at the door of an out-house in the
corner of the orchard. A key turned in a lock, and as he passed
in there was a curious scuffling noise from within. He was only a
minute or so inside, and then I heard the key turn once more and
he passed me and re-entered the house. I saw him rejoin his
guest, and I crept quietly back to where my companions were
waiting to tell them what I had seen.

"You say, Watson, that the lady is not there?" Holmes asked, when
I had finished my report.

"No."

"Where can she be, then, since there is no light in any other
room except the kitchen?"

"I cannot think where she is."

I have said that over the great Grimpen Mire there hung a dense,
white fog. It was drifting slowly in our direction, and banked
itself up like a wall on that side of us, low, but thick and well
defined. The moon shone on it, and it looked like a great
shimmering ice-field, with the heads of the distant tors as rocks
borne upon its surface. Holmes's face was turned towards it, and
he muttered impatiently as he watched its sluggish drift.

"It's moving towards us, Watson."

"Is that serious?"

"Very serious, indeed--the one thing upon earth which could have
disarranged my plans. He can't be very long, now. It is already
ten o'clock. Our success and even his life may depend upon his
coming out before the fog is over the path."

The night was clear and fine above us. The stars shone cold and
bright, while a half-moon bathed the whole scene in a soft,
uncertain light. Before us lay the dark bulk of the house, its
serrated roof and bristling chimneys hard outlined against the
silver-spangled sky. Broad bars of golden light from the lower
windows stretched across the orchard and the moor. One of them
was suddenly shut off. The servants had left the kitchen. There
only remained the lamp in the dining-room where the two men, the
murderous host and the unconscious guest, still chatted over
their cigars.

Every minute that white woolly plain which covered one half of
the moor was drifting closer and closer to the house. Already the
first thin wisps of it were curling across the golden square of
the lighted window. The farther wall of the orchard was already
invisible, and the trees were standing out of a swirl of white
vapour. As we watched it the fog-wreaths