at about nine o’clock on the same evening, a man stood at a large window which overlooked piccadilly and the green park. the room to which the window belonged was justly considered one of the notable sights of london and doubtless would have received suitable mention in the “blue guide” had the room been accessible to the general public. it was, on the contrary, accessible only to the personal friends of mr. nicol brinn. as mr. nicol brinn had a rarely critical taste in friendship, none but a fortunate few had seen the long room with its two large windows overlooking piccadilly.

the man at the window was interested in a car which, approaching from the direction of the circus, had slowed down immediately opposite and now was being turned, the chauffeur’s apparent intention being to pull up at the door below. he had seen the face of the occupant and had recognized it even from that elevation. he was interested; and since only unusual things aroused any semblance of interest in the man who now stood at the window, one might have surmised that there was something unusual about the present visitor, or in his having decided to call at those chambers; and that such was indeed his purpose an upward glance which he cast in the direction of the balcony sufficiently proved.

the watcher, who had been standing in a dark recess formed by the presence of heavy velvet curtains draped before the window, now opened the curtains and stepped into the lighted room. he was a tall, lean man having straight, jet-black hair, a sallow complexion, and the features of a sioux. a long black cigar protruded aggressively from the left corner of his mouth. his hands were locked behind him and his large and quite expressionless blue eyes stared straight across the room at the closed door with a dreamy and vacant regard. his dinner jacket fitted him so tightly that it might have been expected at any moment to split at the seams. as if to precipitate the catastrophe, he wore it buttoned.

there came a rap at the door.

“in!” said the tall man.

the door opened silently and a manservant appeared. he was spotlessly neat and wore his light hair cropped close to the skull. his fresh-coloured face was quite as expressionless as that of his master; his glance possessed no meaning. crossing to the window, he extended a small salver upon which lay a visiting card.

“in!” repeated the tall man, looking down at the card.

his servant silently retired, and following a short interval rapped again upon the door, opened it, and standing just inside the room announced: “mr. paul harley.”

the door being quietly closed behind him, paul harley stood staring across the room at nicol brinn. at this moment the contrast between the types was one to have fascinated a psychologist. about paul harley, eagerly alert, there was something essentially british. nicol brinn, without being typical, was nevertheless distinctly a product of the united states. yet, despite the stoic mask worn by mr. brinn, whose lack-lustre eyes were so unlike the bright gray eyes of his visitor, there existed, if not a physical, a certain spiritual affinity between the two; both were men of action.

harley, after that one comprehensive glance, the photographic glance of a trained observer, stepped forward impulsively, hand outstretched. “mr. brinn,” he said, “we have never met before, and it was good of you to wait in for me. i hope my telephone message has not interfered with your plans for the evening?”

nicol brinn, without change of pose, no line of the impassive face altering, shot out a large, muscular hand, seized that of paul harley in a tremendous grip, and almost instantly put his hand behind his back again. “had no plans,” he replied, in a high, monotonous voice; “i was bored stiff. take the armchair.”

paul harley sat down, but in the restless manner of one who has urgent business in hand and who is impatient of delay. mr. brinn stooped to a coffee table which stood upon the rug before the large open fireplace. “i am going to offer you a cocktail,” he said.

“i shall accept your offer,” returned harley, smiling. “the ‘n. b. cocktail’ has a reputation which extends throughout the clubs of the world.”

nicol brinn, exhibiting the swift adroitness of that human dodo, the new york bartender, mixed the drinks. paul harley watched him, meanwhile drumming his fingers restlessly upon the chair arm.

“here’s success,” he said, “to my mission.”

it was an odd toast, but mr. brinn merely nodded and drank in silence. paul harley set his glass down and glanced about the singular apartment of which he had often heard and which no man could ever tire of examining.

in this room the poles met, and the most remote civilizations of the world rubbed shoulders with modernity. here, encased, were a family of snow-white ermine from alaska and a pair of black manchurian leopards. a flying lemur from the pelews contemplated swooping upon the head of a huge tigress which glared with glassy eyes across the place at the snarling muzzle of a polar bear. mycenaean vases and gold death masks stood upon the same shelf as venetian goblets, and the mummy of an egyptian priestess of the thirteenth dynasty occupied a sarcophagus upon the top of which rested a basrelief found in one of the shrines of the syrian fish goddess derceto, at ascalon.

arrowheads of the stone age and medieval rapiers were ranged alongside some of the latest examples of the gunsmith’s art. there were elephants’ tusks and mexican skulls; a stone jar of water from the well of zem-zem, and an ivory crucifix which had belonged to torquemada. a mat of human hair from borneo overlay a historical and unique rug woven in ispahan and entirely composed of fragments of holy carpets from the kaaba at mecca.

“i take it,” said mr. brinn, suddenly, “that you are up against a stiff proposition.”

paul harley, accepting a cigarette from an ebony box (once the property of henry viii) which the speaker had pushed across the coffee table in his direction, stared up curiously into the sallow, aquiline face. “you are right. but how did you know?”

“you look that way. also—you were followed. somebody knows you’ve come here.”

harley leaned forward, resting one hand upon the table. “i know i was followed,” he said, sternly. “i was followed because i have entered upon the biggest case of my career.” he paused and smiled in a very grim fashion. “a suspicion begins to dawn upon my mind that if i fail it will also be my last case. you understand me?”

“i understand absolutely,” replied nicol brinn. “these are dull days. it’s meat and drink to me to smell big danger.”

paul harley lighted a cigarette and watched the speaker closely the while. his expression, as he did so, was an odd one. two courses were open to him, and he was mentally debating their respective advantages.

“i have come to you to-night, mr. brinn,” he said finally, “to ask you a certain question. unless the theory upon which i am working is entirely wrong, then, supposing that you are in a position to answer my question i am logically compelled to suppose, also, that you stand in peril of your life.”

“good,” said mr. brinn. “i was getting sluggish.” in three long strides he crossed the room and locked the door. “i don’t doubt hoskins’s honesty,” he explained, reading the inquiry in harley’s eyes, “but an a1 intelligence doesn’t fold dress pants at thirty-nine.”

only one very intimate with the taciturn speaker could have perceived any evidence of interest in that imperturbable character. but nicol brinn took his cheroot between his fingers, quickly placed a cone of ash in a little silver tray (the work of benvenuto cellini), and replaced the cheroot not in the left but in the right corner of his mouth. he was excited.

“you are out after one of the big heads of the crook world,” he said. “he knows it and he’s trailing you. my luck’s turned. how can i help?”

harley stood up, facing mr. brinn. “he knows it, as you say,” he replied, “and i hold my life in my hands. but from your answer to the question which i have come here to-night to ask you, i shall conclude whether or not your danger at the moment is greater than mine.”

“good,” said nicol brinn.

in that unique room, at once library and museum, amid relics of a hundred ages, spoil of the chase, the excavator, and the scholar, these two faced each other; and despite the peaceful quiet of the apartment up to which as a soothing murmur stole the homely sounds of piccadilly, each saw in the other’s eyes recognition of a deadly peril. it was a queer, memorable moment.

“my question is simple but strange,” said paul harley. “it is this: what do you know of ‘fire-tongue’?”