"'It's only Carlo, my mastiff. I call him mine, but really old Toller, my groom, is the only man who can do anything with him. We feed him once a day, and not too much then, so that he is always as keen as mustard. Toller lets him loose every night, and God help the trespasser whom he lays his fangs upon. For goodness' sake don't you ever on any pretext set your foot over the threshold at night, for it is as much as your life is worth.'"