ke to water, pretended to bark, and ran to and fro
on the carpet. So far there was no actual fear in his manner, but he was
uneasy and anxious, and nothing would induce him to go within touching
distance of the walking cat. Once he made a complete circuit, but always
carefully out of reach; and in the end he returned to his master's legs
and rubbed vigorously against him. Flame did not like the performance at
all: that much was quite clear.

For several minutes John Silence watched the performance of the cat with
profound attention and without interfering. Then he called to the animal
by name.

"Smoke, you mysterious beastie, what in the world are you about?" he
said, in a coaxing tone.

The cat looked up at him for a moment, smiling in its ecstasy, blinking
its eyes, but too happy to pause. He spoke to it again. He called to it
several times, and each time it turned upon him its blazing eyes, drunk
with inner delight, opening and shutting its lips, its body large and
rigid with excitement. Yet it never for one instant paused in its short
journeys to and fro.

He noted exactly what it did: it walked, he saw, the same number of
paces each time, some six or seven steps, and then it turned sharply and
retraced them. By the pattern of the great roses in the carpet he
measured it. It kept to the same direction and the same line. It behaved
precisely as though it were rubbing against something solid.
Undoubtedly, there was something standing there on that strip of carpet,
something invisible to the doctor, something that alarmed the dog, yet
caused the cat unspeakable pleasure.

"Smokie!" he called again, "Smokie, you black mystery, what is it
excites you so?"

Again the cat looked up at him for a brief second, and then continued
its sentry-walk, blissfully happy, intensely preoccupied. And, for an
instant, as he watched it, the doctor was aware that a faint uneasiness
stirred in the depths of his own being, focusing itself for the moment
upon this curious behaviour of the uncanny creature before him.

There rose in him quite a new realisation of the mystery connected with
the whole feline tribe, but especially with that common member of it,
the domestic cat--their hidden lives, their strange aloofness, their
incalculable subtlety. How utterly remote from anything that human
beings understood lay the sources of their elusive activities. As he
watched the indescribable bearing of the little creature mincing along
the