Now, in spite of their respective ages, it was the regular custom of these two to play together every night before sleep.  Smoke always made the advances, beginning with grave impudence to pat the dog’s tail, and Flame played cumbrously, with condescension.  It was his duty, rather than pleasure; he was glad when it was over, and sometimes he was very determined and refused to play at all.

And this night was one of the occasions on which he was firm.

The doctor, looking cautiously over the top of his book, watched the cat begin the performance.  It started by gazing with an innocent expression at the dog where he lay with nose on paws and eyes wide open in the middle of the floor.  Then it got up and made as though it meant to walk to the door, going deliberately and very softly.  Flame’s eyes followed it until it was beyond the range of sight, and then the cat turned sharply and began patting his tail tentatively with one paw.  The tail moved slightly in reply, and Smoke changed paws and tapped it again.  The dog, however, did not rise to play as was his wont, and the cat fell to parting it briskly with both paws.  Flame still lay motionless.

This puzzled and bored the cat, and it went round and stared hard into its friend’s face to see what was the matter.  Perhaps some inarticulate message flashed from the dog’s eyes into its own little brain, making it understand that the programme for the night had better not begin with play.  Perhaps it only realised that its friend was immovable.  But, whatever the reason, its usual persistence thenceforward deserted it, and it made no further attempts at persuasion.  Smoke yielded at once to the dog’s mood; it sat down where it was and began to wash.

But the washing, the doctor noted, was by no means its real purpose; it only used it to mask something else; it stopped at the most busy and furious moments and began to stare about the room.  Its thoughts wandered absurdly.  It peered intently at the curtains; at the shadowy corners; at empty space above; leaving its body in curiously awkward positions for whole minutes together.  Then it turned sharply and stared with a sudden signal of intelligence at the dog, and Flame at once rose somewhat stiffly to his feet and began to wander aimlessly and restlessly to and fro about the floor.  Smoke followed him, padding quietly at his heels.  Between them they made what seemed to be a deliberate search of the room.

And, here, as he watched them, noting carefully every detail of the performance over the top of his book, yet making no effort to interfere, it seemed to the doctor that the first beginnings of a faint distress betrayed themselves in the collie, and in the cat the stirrings of a vague excitement.

He observed them closely.  The fog was thick in the air, and the tobacco smoke from his pipe added to its density; the furniture at the far end stood mistily, and where the shadows congregated in hanging clouds under the ceiling, it was difficult to see clearly at all; the lamplight only reached to a level of five feet from the floor, above which came layers of comparative darkness, so that the room appeared twice as lofty as it actually was.  By means of the lamp and the fire, however, the carpet was everywhere clearly visible.