“No one will ever make me change my mind,” the man replied.  “This is my last word.”

Quest pointed a threatening finger at him.

“Your last voluntary word, perhaps,” he said, “but science is still your master, Craig.  Science has brought many criminals to their doom.  It shall take its turn with you.  Bring him along, French, to my study.  There is a way of dealing with him.”

* * * * *

Quest felt his forehead and found it damp.  There were dark rims under his eyes.  Before him was Craig, with a little band around his forehead and the mirror where they could all see it.  The Professor stood a little in the background.  Laura and French were side by side, gazing with distended eyes at the blank mirror, and Lenora was doing her best to soothe the terrified niece.  Twice Quest’s teeth came together and once he almost reeled.

“It’s the fight of his life,” he muttered at last, “but I’ve got him.”

Almost as he spoke, they could see Craig’s resistance begin to weaken.  The tenseness of his form relaxed; Quest’s will was triumphing.  Slowly in the mirror they saw a little picture creeping from outline into definite form, a picture of the Professor’s library.  Craig himself was there with mortar and trowel, and a black box in his hand.

“It’s coming!” Lenora moaned.

Quest stood perfectly tense.  The picture suddenly flashed into brilliant clearness.  They saw Craig’s features with almost lifelike detail.  From the corner of that room where the Professor was standing, came a smothered groan.  It was a terrifying, a paralysing moment.  Even the silence seemed charged with awful things.  Then suddenly, without any warning, the picture faded completely away.  A cry which was almost a howl of anger broke from Quest’s lips.  Craig had fallen sideways from his chair.  There was an ominous change in his face.  Something seemed to have passed from the atmosphere of the room, some tense and nameless quality.  Quest moved forward and laid his hand on Craig’s heart.  The girl was on her knees, crying.

“Take her away,” Quest whispered to Lenora.

“What about him?” French demanded, as Lenora led the girl from the room.

“He fought too hard,” Quest said gravely.  “He is dead.  Professor,—­”

They all looked around.  The spot where he had been standing was empty.  The Professor had gone.

CHAPTER XVI

JUSTICE CHEATED

The first shock was over.  Craig’s body had been removed, and the girls had taken Mary, half stunned with grief, to their room.  French and Quest were left alone.

“This is some disappointment,” the former remarked gloomily.

“It is a disappointment,” Quest said slowly, “which may clear the way to bigger things.”

“What’s in your mind now?” French enquired.

Quest shook his head.