The Tracer turned in his chair, picked up the daily detective report, and scanned it until he came to the name Hollis.  It appeared that the daily routine of Rosalind Hollis had not varied during the past three weeks.  In the mornings she was good to the poor with bottles and pills; in the afternoons she tucked one of Lamour’s famous sixteen volumes under her arm and walked to Central Park, where, with democratic simplicity, she sat on a secluded bench and pored over the symptoms of Lamour’s Disease.  About five she retired to her severely simple apartments in the big brownstone office building devoted to physicians, corner of Fifty-eighth Street and Madison Avenue.  Here she took tea, read a little, dined all alone, and retired about nine.  This was the guileless but determined existence of Rosalind Hollis, M.D., according to McConnell, the detective assigned to observe her.

The Tracer refolded the report of his chief of detectives and pigeonholed it just as the door opened and a tall, well-built, attractive young man entered.

Shyness was written all over him; he offered his hand to Mr. Keen with an embarrassed air and seated himself at that gentleman’s invitation.

“I’m almost sorry I ever began this sort of thing,” he blurted out, like a big schoolboy appalled at his own misdemeanors.  “The truth is, Mr. Keen, that the prospect of actually seeing a ‘Carden Girl’ alive has scared me through and through.  I’ve a notion that my business with that sort of a girl ends when I’ve drawn her picture.”

“But surely,” said the Tracer mildly, “you have some natural curiosity to see the living copy of your charming but inanimate originals, haven’t you, Mr. Carden?”

“Yes—­oh, certainly.  I’d like to see one of them alive—­say out of a window, or from a cab.  I should not care to be too close to her.”

“But merely seeing her does not commit you,” interposed Mr. Keen, smiling.  “She is far too busy, too much absorbed in her own affairs to take any notice of you.  I understand that she has something of an aversion for men.”

“Aversion!”

“Well, she excludes them as unnecessary to her existence.”

“Why?” asked Carden.

“Because she has a mission in life,” said Mr. Keen gravely.

Carden looked out of the window.  It was pleasant weather—­June in all its early loveliness—­the fifth day of June.  The sixth was his birthday.

“I’ve simply got to marry somebody before the day after to-morrow,” he said aloud—­“that is, if I want my legacy.”

“What!” demanded the Tracer sharply.

Carden turned, pink and guilty.  “I didn’t tell you all the circumstances of my case,” he said.  “I suppose I ought to have done so.”

“Exactly,” said the Tracer severely.  “Why is it necessary that you marry somebody before the day after to-morrow?”

“Well, it’s my twenty-fifth birthday—­”

“Somebody has left you money on condition that you marry before your twenty-fifth birthday?  Is that it, Mr. Carden?  An uncle?  An imbecile grandfather?  A sentimental aunt?”