In his relations with Smoke he was always absurdly gentle; also he was fatherly; and at the same time betrayed a certain diffidence or shyness.  He recognised that Smoke called for strong yet respectful management.  The cat’s circuitous methods puzzled him, and his elaborate pretences perhaps shocked the dog’s liking for direct, undisguised action.  Yet, while he failed to comprehend these tortuous feline mysteries, he was never contemptuous or condescending; and he presided over the safety of his furry black friend somewhat as a father, loving, but intuitive, might superintend the vagaries of a wayward and talented child.  And, in return, Smoke rewarded him with exhibitions of fascinating and audacious mischief.

And these brief descriptions of their characters are necessary for the proper understanding of what subsequently took place.

With Smoke sleeping in the folds of his fur coat, and the collie lying watchful on the seat opposite, John Silence went down in his motor after dinner on the night of November 15th.

And the fog was so dense that they were obliged to travel at quarter speed the entire way.

* * * * *

It was after ten o’clock when he dismissed the motor and entered the dingy little house with the latchkey provided by Pender.  He found the hall gas turned low, and a fire in the study.  Books and food had also been placed ready by the servant according to instructions.  Coils of fog rushed in after him through the open door and filled the hall and passage with its cold discomfort.

The first thing Dr. Silence did was to lock up Smoke in the study with a saucer of milk before the fire, and then make a search of the house with Flame.  The dog ran cheerfully behind him all the way while he tried the doors of the other rooms to make sure they were locked.  He nosed about into corners and made little excursions on his own account.  His manner was expectant.  He knew there must be something unusual about the proceeding, because it was contrary to the habits of his whole life not to be asleep at this hour on the mat in front of the fire.  He kept looking up into his master’s face, as door after door was tried, with an expression of intelligent sympathy, but at the same time a certain air of disapproval.  Yet everything his master did was good in his eyes, and he betrayed as little impatience as possible with all this unnecessary journeying to and fro.  If the doctor was pleased to play this sort of game at such an hour of the night, it was surely not for him to object.  So he played it, too; and was very busy and earnest about it into the bargain.

After an uneventful search they came down again to the study, and here Dr. Silence discovered Smoke washing his face calmly in front of the fire.  The saucer of milk was licked dry and clean; the preliminary examination that cats always make in new surroundings had evidently been satisfactorily concluded.  He drew an arm-chair up to the fire, stirred the coals into a blaze, arranged the table and lamp to his satisfaction for reading, and then prepared surreptitiously to watch the animals.  He wished to observe them carefully without their being aware of it.