At the last stroke both their hands shot out. Guerchard's fell heavily on the case which held the coronet. The Duke's fell on the brim of his hat; and he picked it up.

Guerchard gasped and choked. Then he cried triumphantly:

"I have it; now then, have I won? Have I been fooled this time? Has Lupin got the coronet?"

"It doesn't look like it. But are you quite sure?" said the Duke gaily.

"Sure?" cried Guerchard.

"It's only the weight of it," said the Duke, repressing a laugh. "Doesn't it strike you that it's just a trifle light?"

"What?" cried Guerchard.

"This is merely an imitation." said the Duke, with a gentle laugh.

"Hell and damnation!" howled Guerchard. "Bonavent! Dieusy!"

The door flew open, and half a dozen detectives rushed in.

Guerchard sank into a chair, stupefied, paralyzed; this blow, on the top of the strain of the struggle with the Duke, had broken him.

"Gentlemen," said the Duke sadly, "the coronet has been stolen."

They broke into cries of surprise and bewilderment,