lights.  One realised then that this was a man of taste.  The furniture and appointments of the room were of dark oak.  The panelled walls were hung with a few choice engravings.  There were books and papers about, a piano in the corner.  A door at the further end led into what seemed to be a sleeping-apartment.  Quest drew up an easy-chair to the wide-flung window, touching a bell as he crossed the room.  In a few moments the door was opened and closed noiselessly.  A young woman entered with a little bundle of papers in her hand.

“Anything for me, Laura?” he asked.

“I don’t believe you will think so, Mr. Quest,” she answered calmly.

She drew a small table and a reading lamp to his side and stood quietly waiting.  Her eyes followed Quest’s as he glanced through the letters, her expression matched his.  She was tall, dark, good-looking in a massive way, with a splendid, almost unfeminine strength in her firm, shapely mouth and brilliant eyes.  Her manner was a little brusque but her voice pleasant.  She was one of those who had learnt the art of silence.

The criminologist glanced through the papers quickly and sorted them into two little heaps.

“Send these,” he directed, “to the police-station.  There is nothing in them which calls for outside intervention.  They are all matters which had better take their normal course.  To the others simply reply that the matter they refer to does not interest me.  No further enquiries?”

“Nothing, Mr. Quest.”

She left the room almost noiselessly.  Quest took down a volume from the swinging book-case by his side, and drew the reading lamp a little closer to his right shoulder.  Before he opened the volume, however, he looked for a few moments steadfastly out across the sea of roofs, the network of telephone and telegraph wires, to where the lights of Broadway seemed to eat their way into the sky.  Around him, the night life of the great city spread itself out in waves of gilded vice and black and sordid crime.  Its many voices fell upon deaf ears.  Until long past midnight, he sat engrossed in a scientific volume.

CHAPTER II

THE APARTMENT-HOUSE MYSTERY

1.

“This habit of becoming late for breakfast,” Lady Ashleigh remarked, as she set down the coffee-pot, “is growing upon your father.”

Ella glanced up from a pile of correspondence through which she had been looking a little negligently.

“When he comes,” she said, “I shall tell him what Clyde says in his new play—­that unpunctuality for breakfast and overpunctuality for dinner are two of the signs of advancing age.”

“I shouldn’t,” her mother advised.  “He hates anything that sounds like an epigram, and I noticed that he avoided any allusion to his birthday last month.  Any news, dear?”

“None at all, mother.  My correspondence is just the usual sort of rubbish—­invitations and gossip.  Such a lot of invitations, by-the-bye.”