have seen angels and devils. The deaf will repeat conversations in which they profess to have just taken a part. A single hallucination may exist, or several at the same time; all the senses are liable to be affected by them.

In the third section are classed those hallucinations which are associated with another error of the senses, to which the name of illusion has been given; both these states consist of false impressions of the senses. In the first case there is a vision without the presence of any material object to produce it, while in the second the object, exists, but it produces an impression different to the reality—a man assumes the appearance of a woman; a piece of wood becomes a hideous monster. Illusions sometimes appear in the manner of an epidemic. The occurrence of these epidemics is not rare in history. Every sense is subject to illusions, and all of them may be so at the same time. Not unfrequently illusions are accompanied by reprehensible and dangerous acts.

Hallucinations are especially frequent in insanity. The fourth section contains those which are combined with monomania and other forms of insanity. The kinds of monomania most liable to this complication are lypemania, delirium tremens, demonomania, erotomania, nostalgia, &c. A species of demonomania formerly prevailed to a considerable extent, in which the persons who were attacked imagined they had relations with demons who were termed Incubi and Succubi. To this division belong those hallucinations which show themselves in that particular form of insanity which is known as stupidity.

The fourth section also contains the hallucinations which accompany mania; they are very frequently combined with illusions, or these two conditions may occur alternately. The hallucinations which show themselves in delirium tremens, and in the frenzy arising from narcotic poisons, form the subject of the fifth section. We have considered it right to separate the hallucinations

which arise from the use of these substances, because they are not necessarily accompanied by insanity; they are spoken of in that part of our work which treats of the causes of hallucinations.

In the sixth section are arranged those hallucinations which are complicated with catalepsy, epilepsy, hysteria, hypochondriasis, &c.

The hallucinations of night-mare and dreams form the seventh section. It is evident that night-mare, in certain respects, resembles insanity, and that it is observed in this disorder. It is the same with regard to dreams, which bear a strong analogy to hallucinations. The study of the physiology of dreams has supplied us with certain facts of peculiar interest; the presentiments which happen in this state are, we conceive, explained in most instances by the existence of hallucinations. Nevertheless, presentiments do not occur exclusively in dreams, nor can they always be explained by hallucinations. Lastly, we have shown that nocturnal hallucinations have sometimes occurred in the form of an epidemic.

There is a singular condition of the mind, known under the name of ecstasy, which has justly attracted the attention of allobservers. The hallucinations which are one of its distinctive characters we have placed in the eighth section. The concentration of the mind upon one particular object for a long time may give rise to an ecstatic condition of the brain, in which an image of the object is produced, and reäcts upon the mind as if it really existed. It is to this mental state that the visions of celebrated men are to be referred. We have several times noticed the occurrence of ecstasy in children, and have also seen it in catalepsy, hysteria, exaggerated states of mysticism, and in insanity.

Certain peculiar phenomena, such as prevision, clairvoyance, second-sight, animal magnetism, and somnambulism, seem to us to be commonly due to a state of ecstasy. The effect of cold may be to produce this state of the nervous system. The ecstatic

state has been observed in all ages, and lately occurred in several thousand persons in Sweden. The hallucinations observed in these different conditions of the nervous system, especially in somnambulism, may give rise to conduct which would entail a grave responsibility on the individual.

The ninth section contains those hallucinations which are complicated with febrile disorders, or with acute, inflammatory, chronic, or other diseases, and with certain conditions of the atmosphere.

Lastly, in the tenth section we have associated the epidemic hallucinations and illusions to which we have previously referred.

This classification includes all the varieties of hallucinations which have come under our own notice, and to it we think may be referred all that are likely to occur.

The numerous divisions we have established show that hallucinations arise from different causes. Their primary division into moral and physical, as indicated at the commencement of this chapter, are the centres to which converge a number of secondary causes. As in insanity, the dominant ideas have considerable influence on the nature of the hallucination; thus when a belief in demonology, sorcery, magic, lycanthropy, or vampirism prevails, men see devils, sorcerers, were-wolves, vampires, &c. The character of the hallucinations also varies with the kind of civilization; thus, with the Greeks, they assumed the form of pans, fauns, and naïads; with the Romans, that of genii; and in the Middle Ages, that of angels, saints, and devils. In our own times every possible combination of the ideas may lay the foundation of them. When physical causes give rise to hallucinations, the latter will have corresponding characters.

Properly speaking, only the secondary causes of hallucinations are treated of in the preceding paragraph; it is necessary that they should be considered from a more elevated point of view; and this has been attempted in a chapter especially devoted to

their physiological, historical, moral, and religious aspect. In the first part of this chapter we have endeavored to show that the primary cause of hallucinations lies in the violation of certain leading principles, and in an ill-regulated condition of the ideas, which ultimately result in an abnormal reproduction of their sensible signs. After entering upon a more extended consideration. of the nature of ideas, of their subdivisions, of the principal operations of the mind which are concerned in the production of hallucinations, we have shown that these ought frequently to be regarded as occurring in an almost normal state of things, as we have pointed out when speaking of physiological ecstasy. This mode of regarding hallucinations enables us to explain how it is that many celebrated men have been subject to them, and yet must not be looked upon as having been insane. The examples of Loyola, of Luther, of Joan of Arc, are decisive proofs of the correctness of this opinion.

All our arguments are especially intended to show that these illustrious persons were the impersonation of an epoch, of some special idea; that they fulfilled some useful and necessary mission, and that their hallucinations were altogether different from those which are observed in the present day. In this chapter we have also endeavored to distinguish between the apparitions of Scripture and those of profane history, as well as those of many Christians. If we are not mistaken, we have thus presented. the doctrine of hallucinations in a more complete form than has hitherto been done.

Examinations after death of the bodies of the insane afford no satisfactory information with respect to hallucinations; and we participate in the opinion of most medical men on this point, that the pathological anatomy of hallucinations is still to be accomplished.

Until lately, any special treatment for hallucinations can scarcely

be said to have existed. Leuret, in protesting against this error, has proved that the hallucinated, when properly managed, are capable of being cured. While acknowledging the talents of this practitioner, we have found it necessary to restrict the employment of his method; at the same time, we can refer to facts in justification of the treatment we have proposed, and which seems to us to be capable of a more general application.

Our task would not have been completed unless we had examined the subject of hallucinations in their relation to our civil and criminal institutions. It is shown by numerous examples that the hallucinated may, under the influence of their false impressions, commit dangerous and even criminal acts. This fact is placed beyond a doubt in the course of this work. It was therefore most important to establish characters which should serve to distinguish true cases of hallucination from those which are simulated. These characters are obtained by inquiring into the history of the case, by interrogating, by examining the writings, and by prolonged observation of the individual. By the use of these means we consider that magistrates, as well as medical men, have the power of distinguishing between the hallucinated and criminals. The question of confinement is previously discussed when speaking of the treatment, but it is there reconsidered. Useful in a great number of cases, especially when the person is dangerous, it could not be enforced in others without great injury to the individual. Lastly, we have terminated this chapter by proving that the capability of making a will remains in those cases where the hallucinations do not influence the acts of the individual. But we have shown that this is no longer the case where the affections of the hallucinated have become perverted-as, for example, when he believes a relative is transformed into the devil, or that he charges himself with electricity for the purpose of poisoning his food or of tormenting him, &c.