“I did it.  Then I left.  The next morning I read of the case in the papers and I have followed it closely since.  I knew you were ostensibly on the wrong track and as a matter of self-preservation I determined to keep my mouth shut unless it happened that the wrong person was accused.  Had you charged someone else with the killing I assure you I would have come forward.  But meanwhile—­not even knowing the identity of the woman in the taxi—­there seemed no necessity for running the risk.  There was nothing save my own word to prove self-defense, you see.”

“There is now,” said Carroll.  Hazel started eagerly and he smiled upon her.  “The story of the woman who actually was in the taxicab substantiates yours, Gresham.  She had followed Warren into the yards to talk to him.  She saw the whole affair from a distance—­and then went back through the waiting room of the station and called the taxi in which you had placed Warren’s body.”

“Then Garry will be freed?” cried the girl hopefully:  “His plea of self-defense will acquit him?”

“Undoubtedly,” retorted Carroll.  “Don’t you think so, Leverage?”

“Surest thing you know,” returned the chief heartily.  “And I’m darned glad of it!”

Garry faced his sister.  “How did you know that I had killed him, Sis?”

“I didn’t,” she answered quietly.  “Not at first, anyway.  But, if you remember, you came in the house a little after eleven o’clock that night and seemed excited.  You came to my room—­”

“I was thinking then,” explained Garry, “that maybe you were eloping with Warren.”

“Then you came home again a little after one o’clock.  You waked me then—­and acted peculiarly.”

“I was reassuring myself,” he said, “that you really hadn’t left the house.”

“The next morning while you were taking your shower I was putting up your laundry,” Hazel went on.  “I found a revolver in your drawer.  I didn’t think anything of it then—­I hadn’t even read the papers about the—­the—­killing.  But later, I remembered it.  I went back to look for the revolver—­just why, I don’t know—­and it was gone.  I questioned you about it a couple of days later, and you denied that you had ever had a revolver in the house.  And I knew then, Garry—­I knew that you had done it.”

He squeezed her hand.  “We always did know more about each other than we were told, didn’t we, Little Sis?  Because at that moment, too, I knew that you knew!”

The young man turned back to the detectives—­“And what now?” he questioned.

“We’ll have to hold you, Gresham.  You’ll have to go through the form of a trial—­but you’ll get off, don’t worry!”

Sister and brother left the room hand-in-hand.  Alone again, the two detectives faced each other.  “You win, David,” said Leverage admiringly.  “Though darned if I know how you do it?”

“A combination of luck and common sense,” returned Carroll simply.  “This time it was principally luck.  It usually is in such cases—­but most detectives don’t admit it.  It is the wild-eyed reporter with the vivid imagination whom we can thank for this solution.  It was his fiction that brought about Miss Gresham’s ridiculous confession and that which caused me to know that she must be shielding her brother.  As to how matters stand—­I say Thank God!”