"Exactly. Now, Mrs. Pitman, this knife. Can you identify it positively?"
"I can."
"But isn't it true that this is a very common sort of knife? One that nearly every housewife has in her possession?"
"Yes, sir. But that knife handle has three notches in it. I put the notches there myself."
"Before this presumed crime?"
"Yes, sir."
"For what purpose?"
"My neighbors were constantly borrowing things. It was a means of identification."
"Then this knife is yours?"
"Yes."