Alicia has a round, snow-white chin, and when she tilts it the curve of her throat is distracting.

“On second thoughts,” said The Author, critically, “I discover that I do not wholly disapprove of you.  Come outside.  I wish to talk about the venerable, and yet common design that tops every outside window and door of this house.—­What do you call that design, may I ask?”

“Why, everybody knows the Greek fret!” said Alicia, staring at it.  “It’s as old as the hills.”

“Exactly,” agreed The Author.  “The Greek fret is as old as the hill.  And, with the single exception of the swastika, it is the design most universally known to man.  You may find it on a bit of ancient Greek pottery, or on a crumbling wall in Yucatan.  Many people refer to it as the Greek key.”

Something began to glimmer in my mind—­the vaguest, most tenuous shadow of an idea; a tantalizing, hide-and-seek phantom of a thought.

          “Turne Hellens Keye
          Three Tennes and Three,”

he quoted the doggerel verse.

We looked at him mutely.

“It is a tiresome truism,” he went on, reflectively, “that what lies close to the eye often escapes observation.  For instance, these windows have been staring at me daily, each with its nice little eyebrow of design, and I overlooked the design until my subconscious mind suggested to me that here, in all probability, lies Hellen’s Keye.”

I remembered the entry in Freeman’s diary, concerning the loss of a “Keye,” which hadn’t been found among his father’s papers, and of a secret which had died with the older man.

“I think I told you,” said The Author, “that this house was built by master masons, shortly after the Grand Lodge was established in London.  Thirty-three is rather a significant number.  Yet, how to apply it,” he paused, frowning.

“Without disturbing a Watcher in the Dark?” Alicia made light of The Authors itch for mystery.  “Aren’t you rather forgetting the Watcher in the Dark?  Teller of tales, isn’t it moon-stuff you’re trying to spin?”

“Who talks of a Watcher in the Dark?” asked a pleasant voice.  Accompanied by Mr. Johnson, Mr. Nicholas Jelnik had strolled up unperceived.

“The Author,” Alicia explained, mischievously, “is trying to make sense out of nonsense.”

“That,” said Mr. Jelnik, smiling, “is not an uncommon occupation.”

“It’s all about a bit of doggerel we found on a scrap of paper in the attic,” I told him.  And I quoted it, adding:  “There was a column of dots under it.  The Author laments that he lost it, before he had chance to unravel it.”

“I lost it, walking in my sleep,” said The Author, disagreeably.

“And now he’s trying to make us believe that the design in the brick-work above our windows, just because it’s the Greek fret, is Hellen’s Keye,” Alicia said, jestingly.

“Well, you know, if a thing means anything, it’s got to mean something,” put in Mr. Johnson.