"Nine A.M." came the reply. "And what's the idea of calling me at home in the middle of the night to ask a question like that?"
"Not until nine A.M.?" the man asked in a disappointed voice.
"No, not till nine A.M.!" the librarian said. "Why do you want to get in before nine A.M.?"
"Who said I wanted to get in?" the man sighed sadly. "I want to get out."