y is perfect which does not at some point ally itself
with the mysterious"; and he became suddenly aware that the presence of
the dog in this foggy, haunted room on the top of Putney Hill was
uncommonly welcome to him. He was glad to feel that Flame's dependable
personality was with him. The savage growling at his heels was a
pleasant sound. He was glad to hear it. That marching cat made him
uneasy.

Finding that Smoke paid no further attention to his words, the doctor
decided upon action. Would it rub against his leg, too? He would take it
by surprise and see.

He stepped quickly forward and placed himself upon the exact strip of
carpet where it walked.

But no cat is ever taken by surprise! The moment he occupied the space
of the Intruder, setting his feet on the woven roses midway in the line
of travel, Smoke suddenly stopped purring and sat down. It lifted up its
face with the most innocent stare imaginable of its green eyes. He could
have sworn it laughed. It was a perfect child again. In a single second
it had resumed its simple, domestic manner; and it gazed at him in such
a way that he almost felt Smoke was the normal being, and _his_ was the
eccentric behaviour that was being watched. It was consummate, the
manner in which it brought about this change so easily and so quickly.

"Superb little actor!" he laughed in spite of himself, and stooped to
stroke the shining black back. But, in a flash, as he touched its fur,
the cat turned and spat at him viciously, striking at his hand with one
paw. Then, with a hurried scutter of feet, it shot like a shadow across
the floor and a moment later was calmly sitting over by the
window-curtains washing its face as though nothing interested it in the
whole world but the cleanness of its cheeks and whiskers.

John Silence straightened himself up and drew a long breath. He realized
that the performance was temporarily at an end. The collie, meanwhile,
who had watched the whole proceeding with marked disapproval, had now
lain down again upon the mat by the fire, no longer growling. It seemed
to the doctor just as though something that had entered the room while
he slept, alarming the dog, yet bringing happiness to the cat, had now
gone out again, leaving all as it was before. Whatever it was that
excited its blissful attentions had retreated for the moment.

He realized this intuitively. Smoke evidently realized it, too, for
presently he deigned to march back to the firep