"Four days since," replied Robin dropping into a chair, "as if you didn't know! Why do you come here to exult over me?"
"Because I wish to tell you that you are wrong in thinking I put that cipher in the paper. As I wrote to you from Saxham I decided to let the matter rest. Whether your father was guilty or innocent I did not care so long as you and he left Marsh alone. The man who put that into the paper was Santiago."
"I do not believe it."
Herrick shrugged his shoulders. "As you please; but it is true for all that. I know the cipher, but I give you my word I did not insert it. You knew the cipher, and I am sure you did not use it to betray your father. The only other person who knew it was the Don, and he has left this last sting behind him out of revenge for losing the money."
Robin shook his head. "I might believe that," he said, "if I did not know it was you."
"But I tell you it was not!" cried Jim impatiently.
"It was. It was. Those private detectives who worked for you told me all about it. You told them to have my father arrested."
"Belcher and Kidd!" cried Herrick jumping up.
"Ah, you know the name. Yes. They gave notice to the police and had my poor father taken. I guessed it was their work and through you."
Dr. Jim stood for a moment in a brown study. He saw well enough what had occurred. The ferret had made use of Santiago to find out the business, and knowing of the reward had made use of the information extorted from Santiago. "I expect they let him leave England on condition that he told them the business and helped them to trap Frisco by means of the cipher. The scoundrels!"