He handed the negro a quarter, which was complete in its logic.

As he reached the floor, he waved to the elevator operator.  “Go on down, and don’t let any one else come up, for Mr. Greenough doesn’t want company.”

As the car slid down, Shirley fumbled along the familiar hall to the iron stairs which led to the roof of the building.  Up these he hurried, thence out upon the roof.  It was a matter of only four minutes before he had crossed to the next apartment building, opened the door of the roof-entry, found the stairs to the ninth floor, and taken this elevator to the street.

He walked out of the building, and turned toward Central Park West, to slyly observe the entrance of the building where waited the faithful hansom Jehu.  A young man was in conversation with the driver, and the big automobile could be seen on the other side of the street awaiting further developments.

“He has a long vigil there,” laughed Shirley.  “Now, for the real address.  I think I lost the hounds for this time.”

Another vehicle took him through the Park to the darkened mansion of the Van Clefts’.  Here, Shirley’s card brought a quick response from the surprised son of the dead millionaire.

“Why—­why—­I’m glad to see you, Mr. Shirley—­Who sent you?” he began.

Shirley registered complete surprise.  “Sent me, my dear Van Cleft?  Who should send me?  For what?  It just happened that I was walking up the Avenue, and to-morrow night I plan to give a little farewell supper to Hal Bingley, class of ’03, at the club You knew him in College?  I thought you might like to come.”

“Step in the library,” requested Van Cleft, weakly.  “Sit down, Mr. Shirley—­I’m upset to-night.”

He mopped his brow with a damp handkerchief, and Shirley’s big heart went out to the young chap, as he saw the haggard lines of horror and grief on his usually pleasant face.

“What’s the trouble, old man?  Anything I can do?”

“My father just died this evening, and I’m in awful trouble—­I thought it was the Coroner, or the police—­” he bit his tongue as the last words escaped him.  Shirley put his hand on Van Cleft’s shoulder, with an inspiring firmness.

“Tell me how I can help.  You’ve had a big shock.  Confide in me, and I pledge you my word, I’ll keep it safer than any one you could go to.”

Van Cleft groped as a drowning man, at this opportunity.  He caught Shirley’s hand and wrung it tensely.

“Sit down.  The doctor is still upstairs with mother and sister.  When the Coroner comes, I would like to have you be here as a witness.  It’s an ordeal—­I’ll tell you everything.”

Shirley listened attentively, without betraying his own knowledge.  Soothing in manner, he questioned the son about any possible enemy of the murdered man.

“There’s not one I know.  Dad is popular—­he’s been too gay, lately, but just foolish like a lot of rich men.  He wouldn’t harm any one.  He inherited his money, you know.  Didn’t have to crush the working people.  Like me, he’s been endeavoring to spend it ever since he was born, but it comes in too fast from our estates.”