this breath of
decay rising to his nostril, Cairn found something fearsome. He opened
the door, stepped out on to the landing, and closed the door behind
him.

At an hour close upon midnight, Dr. Bruce Cairn, who was about to
retire, received a wholly unexpected visit from his son. Robert Cairn
followed his father into the library and sat down in the big, red
leathern easy-chair. The doctor tilted the lamp shade, directing the
light upon Robert's face. It proved to be slightly pale, and in the
clear eyes was an odd expression--almost a hunted look.

"What's the trouble, Rob? Have a whisky and soda."

Robert Cairn helped himself quietly.

"Now take a cigar and tell me what has frightened you."

"Frightened me!" He started, and paused in the act of reaching for a
match. "Yes--you're right, sir. I _am_ frightened!"

"Not at the moment. You have been."

"Right again." He lighted his cigar. "I want to begin by saying
that--well, how can I put it? When I took up newspaper work, we
thought it would be better if I lived in chambers--"

"Certainly."

"Well, at that time--" he examined the lighted end of his
cigar--"there was no reason--why I should not live alone. But now--"

"Well?"

"Now I feel, sir, that I have need of more or less constant
companionship. Especially I feel that it would be desirable to have a
friend handy at--er--at night time!"

Dr. Cairn leant forward in his chair. His face was very stern.

"Hold out your fingers," he said, "extended; left hand."

His son obeyed, smiling slightly. The open hand showed in the
lamplight steady as a carven hand.

"Nerves quite in order, sir."

Dr. Cairn inhaled a deep breath.

"Tell me," he said.

"It's a queer tale," his son began, "and if I told it to Craig Fenton,
or Madderley round in Harley Street I know what they would say. But
you will _understand_. It started this afternoon, when the sun was
pouring in through the windows. I had to go to my chambers to change;
and the rooms were filled with a most disgusting smell."

His father started.

"What kind of smell?" he asked. "Not--incense?"

"No," replied Robert, looking hard at him--"I thought you would ask
that. It was a smell of something putrid--something rotten, rotten
with the rottenness of ages."

"Did you trace where it came from?"

"I opened all the windows, and that seemed to disperse it for a time.
Then, just as I was going out, it returned; it seemed to envelop me
like a filthy mia