The material of raving thought is chiefly the objects upon which the mind ordinarily dwells: the bricklayer’s mind wanders amidst bricks; the medical man commonly wishes to visit his patients. But maidens do not mutter their lovers’ names nor men their liaisons in preference to anything else. Delirium is but a modification of our ordinary thought; frequently it is little more than incoherent thought.The unstable brain is easily perturbed; and if the eye sees but imperfectly, then a flood of erroneous ideas is inaugurated.