“A good idea,” commented Narkom.  “Come on, Sir Horace.  Is this the way?”

“Yes, but you’ll have to tread carefully, and mind you don’t fall over anything.  A good deal of my paraphernalia—­bottles, retorts and the like—­is stored in the little recess at the foot of the staircase, and my assistant is careless and leaves things lying about.”

Evidently the caution was necessary, for a minute or so after they had passed on and disappeared behind the door leading to the kitchen stairway, Petrie and his colleagues heard a sound as of something being overturned and smashed, and laughed softly to themselves.  Evidently, too, the danger of the furnace had been grossly exaggerated by Sir Horace, for when, a few minutes later, the door opened and closed, and Narkom’s men, glancing toward it, saw the figure of their chief reappear, it was plain that he was in no good temper, since his features were knotted up into a scowl, and he swore audibly as he snapped the shutter over the bull’s-eye and handed it back to Petrie.

“Nothing worth looking into, superintendent?”

“No—­not a thing!” he replied.  “The silly old josser! pulling me down there amongst the coals and rubbish for an insane idea like that!  Why, the flues wouldn’t admit the passage of a child; and even then, there’s a bend—­an abrupt ’elbow’—­that nothing but a cat could crawl up.  And that’s a man who’s an authority on the human brain!  I sent the old silly back to bed by the way he came, and if—­”

There he stopped, stopped short, and sucked in his breath with a sharp, wheezing sound.  For, of a sudden, a swift pattering footfall and a glimmer of moving light had sprung into being and drawn his eyes upward; and there, overhead, was Miss Lome coming down the stairs from the upper floor in a state of nervous excitement, and with a bedroom candle in her shaking hand, a loose gown flung on over her nightdress, and her hair streaming over her shoulders in glorious disarray.

He stood and looked at her, with ever-quickening breath, with ever-widening eyes, as though the beauty of her had wakened some dormant sense whose existence he had never suspected; as though, until now, he had never known how fair it was possible for a woman to be, how fair, how lovable, how much to be desired; and whilst he was so looking she reached the foot of the staircase and came pantingly toward him.

“Oh, Mr. Narkom, what was it—­that noise I heard?” she said in a tone of deepest agitation.  “It sounded like a struggle—­like the noise of something breaking—­and I dressed as hastily as I could and came down.  Did he come?  Has he been here?  Have you caught him?  Oh! why don’t you answer me, instead of staring at me like this?  Can’t you see how nervous, how frightened, I am?  Dear Heaven! will no one tell me what has happened?”

“Nothing has happened, miss,” answered Petrie, catching her eye as she flashed round on him.  “You’d better go back to bed.  Nobody’s been here but Sir Horace.  The noise you heard was me a-grabbing of him, and he and Mr. Narkom a-tumbling over something as they went down to look at the furnace.”