"What does he mean? Can he possibly suspect me?" thought Wolverton, fixing his eyes on Bob's face. "But no! I certainly didn't take any money from him."
"You may be right," he said aloud; "but that hasn't anything to do with my claim for interest. Whether your father was robbed of the money, or spent it, is all one to me. It wasn't paid to me, I can certify."
"Would you be willing to swear that the money was not paid to you that day, Mr. Wolverton?"
"Do you mean to insult me? Haven't I told you it was not paid?"
"Do you expect me to pay it to you, then?" asked Mrs. Burton.
"Widder, I am surprised you should ask such a foolish question. It lies in a nutshell. I'm entitled to interest on the money I let your husband have on mortgage. You admit that?"
"I'm glad you admit that. As your husband didn't pay, I look to you for it. I can say no more."
Mrs. Burton took a pocket-book from a pocket in her dress, and handed it to Robert. Bob opened it, and drew therefrom a folded paper.
"Mr. Wolverton," he said, quietly, "I hold in my hand a receipt signed by yourself for the interest--one hundred and fifty dollars--dated the very day that my poor father died. What have you to say to it?"
Mr. Wolverton sprang to his feet, pale and panic-stricken.
"Where did you get that paper?" he stammered, hoarsely.
[Illustration: BOB PRODUCES THE MISSING RECEIPT.]
"When my poor husband left your office this receipt was in his possession," answered Mrs. Burton.
"I deny it," exclaimed Aaron Wolverton, in a tone of excitement.
"Where else should it be?" inquired the widow, eying him fixedly.
"So you deny that the signature is yours, Mr. Wolverton?"
"I would rather not," said Bob, drawing back the receipt from Wolverton's extended hand.
"That's enough!" said Wolverton quickly. "You are afraid to show it. I denounce it as a base forgery."
"That will do no good," said the boy, un-terrified. "I have shown the receipt to Mr. Dornton, and he pronounces the signature genuine."
"What made you show it to him?" asked Wolverton, discomfited.
"Because I thought it likely, after your demanding the interest the second time, that you would deny it."
"Probably I know my own signature better than Mr. Dornton can."
"I have no doubt you will recognize it," and Bob, unfolding the paper, held it in such a manner that Wolverton could read it.