“None.  It’s a blank wall on the left, and one door on the right—­the one opening into the Kazmah office.  There are other premises on the same floor, but they are across the landing.”

“What premises?”

“A solicitor and a commission agent.”

“The floor below?”

“It’s all occupied by a modiste, Renan.”

“The top floor?”

“Cubanis Cigarette Company, a servants’ and an electrician.”

“Nae more?”

“No more.”

“Where does yon back stair open on the topmaist floor?”

“In a corridor similar to that alongside Kazmah’s.  It has two windows on the right overlooking a narrow roof and the top of the arcade, and on the left is the Cubanis Cigarette Company.  The other offices are across the landing.”

Mary Kerry stared into space awhile.

“Kazmah and Mrs. Irvin could ha’ come down to the fairst floor, or gene up to the thaird floor unseen by the Spinker man,” she said dreamily.

“But they couldn’t have reached the street, my dear!” cried Kerry.

“No—­they couldn’a ha’ gained the street.”

She became silent again, her husband watching her expectantly.  Then: 

“If puir Sir Lucien Pyne was killed at a quarter after seven—­the time his watch was broken—­the native sairvent did no’ kill him.  Frae the Spinker’s evidence the black man went awe’ before then,” she said.  “Mrs. Irvin?”

Kerry shook his head.

“From all accounts a slip of a woman,” he replied.  “It was a strong hand that struck the blow.”

“Kazmah?”

“Probably.”

“Mr. Quentin Gray came back wi’ a cab and went upstairs, free the Spinker’s evidence, at aboot a quarter after seven, and came doon five meenites later sair pale an’ fretful.”

Kerry surrounded himself and the speaker with wreaths of stifling smoke.

“We have only the bare word of Mr. Gray that he didn’t go in again, Mary; but I believe him.  He’s a hot-headed fool, but square.”

“Then ’twas yon Kazmah,” announced Mrs. Kerry.  “Who is Kazmah?”

Her husband laughed shortly.

“That’s the point at which I got stumped,” he replied.  “We’ve heard of him at the Yard, of course, and we know that under the cloak of a dealer in Eastern perfumes he carried on a fortune-telling business.  He managed to avoid prosecution, though.  It took me over an hour tonight to explore the thought-reading mechanism; it’s a sort of Maskelyne’s Mysteries worked from the inside room.  But who Kazmah is or what’s his nationality I know no more than the man in the moon.”

“Pairfume?” queried the far-away voice.

“Yes, Mary.  The first room is a sort of miniature scent bazaar.  There are funny little imitation antique flasks of Kazmah preparations, creams, perfumes and incense, also small square wooden boxes of a kind of Turkish delight, and a stock of Egyptian mummy-beads, statuettes, and the like, which may be genuine for all I know.”