None of the staff but Filch seemed to be stirring themselves to help her. Indeed, a week after Free and George’s departure Harry witnessed Professor McGonagall walking right past Peeves, who was determinedly loosening a crystal chandelier, and could have sworn he heard her tell the poltergeist out of the corner of her mouth, “It unscrews the other way.”

Harry Potter and the Order of the Phoenix – J.K. Rowling