“Justice calls.”

It was the signal, and, at last, it had been given correctly. It came as a surprise to Frank, for he had begun to believe that De Villefort would fail to give it. Merry hesitated, for, even though the signal had been given, he felt a strange reluctance to part with the precious ball delivered into his hands by the dead Duke of Benoit de Sault.

The Frenchman lowered his eyes, and stood looking at the youth expectantly, commandingly. Slowly, Frank felt in his pocket for the precious ball. He felt a great desire to know what secret it contained that might serve to bring justice to the wretched prisoner of Devil’s Island.

Merry drew the metal ball from his pocket, and the eyes of De Villefort glittered strangely when he saw it. The man seemed to be holding himself in check.

“Here it is,” said Frank regretfully. “I have thought that I should be glad to get rid of it, but now I part with it most reluctantly, I confess.”

Then he looked up suddenly, and surprised that strange, crafty, triumphant look in the glittering eyes of the Frenchman. It gave Frank a shock. It was as if some one had shouted into his ears, “Beware—beware! He is fooling you!” Frank had been on the point of delivering up the mysterious ball, but now he hesitated.

De Villefort became aware that something had aroused the suspicions of the shrewd American. And then, like a flash, the Frenchman’s arm darted out, and his fingers snatched the ball from Frank! That act told Frank Merriwell as plainly as words that the man had no right to the tiny sphere.

“Thank you, Monsieur Merriwell!” cried Murat de Villefort triumphantly. “You have guarded the treasure well, and you may be consoled to know it has reached good hands at last.”

He laughed outright, and that laugh was as if he had struck Merriwell between the eyes. It removed the last doubt from Frank’s mind. Although the man had given the signal, he had no right to the metal ball. The precious sphere had fallen into the hands of the enemies of Dreyfus!

That ball had brought nothing but trouble and danger to Frank, and almost any other person would have felt gladness to get rid of it, especially as he could know he had fulfilled his promise to the dead duke. Not so Frank Merriwell. In an instant flashed before his eyes a vision of the poor wretch on the burning rock of Devil’s Island, doomed to spend the remainder of his days there, just because that tiny ball had fallen into hands for whom it was never intended!