no dispute, that a certain quantity of alcohol taken into the human stomach will cause the drinker to fall into _delirium tremens_; and that in that state the patient will, with his waking eyes, see objects of a particular kind; in nine cases out of ten, the forms of rats and mice running over his bed, and about his person. There is no public delusion here, no popular mind possessed with a fixed idea of these appearances, to which the individual delusions might be referred; yet the swallower of the alcohol in Dublin, and the swallower of the alcohol in Calcutta, will both see exactly the same sorts of appearances, and will both express precisely the same horror and disgust at their supposed tormentors. Is it the case, then, that, as the forms of rats and mice come into the minds of men in one kind of mental sickness, the forms of men and women riding on goats and broomsticks through the air, and the other apparatus of the witch-sabbaths, may have been but the manifestations of another disordered state of the mental organism, a symptom merely and concomitant of an epidemical disease? It is easy enough to understand how symptoms so simple as the appearance of what are usually called "blue devils" should be constant in their attendance on a particular state of cerebral disorder; but when the hallucination becomes so complex as in the fantasies of witchcraft, it is difficult to suppose that that long train of appearances and imaginary transactions should follow on a merely pathological derangement of the brain. Between the two alternatives of referring these hallucinations to such a cause, on the one hand, or to a mesmeric sympathy, as above suggested, between the individual and the crowd of the possessed, on the other, it is hard to choose; but, perhaps, the latter will appear to offer the less amount of difficulty. In the present state of knowledge, however, it would be rash to say that a particular state of diseased cerebral action might not be attended with a perfect set of supposed phenomena as complex and constant in the minds of the sufferers, as those which existed among the victims of demonomania.