The power of reproducing hallucinations by an effort of the will has been described by numerous observers.

* Conolly, p. 119, op. cit.

On this subject, Jerome Cardan thus expresses himself: "Video quae volo, oculis, non vi mentis."*

One of the most curious cases of this nature is that of the painter mentioned in the early part of this work. He only needed to seek in his brain for the image of the model which he wished to see, than it was reproduced in the arm-chair, with all the vividness of life. Blake, the Seer, conversed tranquilly with the various dead who came to visit him, and described to the surprised witnesses their costume, physiognomy, and conversation. Talma, by the force of his will, metamorphosed the spectators of his immense talent into skeletons.

M. Michea writes as follows: "A monomaniac of a cultivated and ardent mind instantaneously converted all the ideas which passed through his mind into false visual perceptions. He had only to imagine a thing or a person, when it immediately assumed a material form. One day," said M. Michla, "we found him with eyes fixed, a smiling mouth, and in the act of clapping his hands in sign of applause. He did not hear us open the door of his room. To our question: 'What does this mean? What are you doing?' 'I am,' he replied, 'like the fool that Horace speaks of: I am seeing an imaginary play. I was wearied by my fireside; I am fond of the beauties of the opera, and have been playing to myself the ballet of The Sylphide; and when you touched me on the shoulder, I was applauding Taglioni, with whose graceful and noble dancing I had never before been so much charmed."†

A young man, said M. Baudry, was much engaged in projects of canal constructing. One day, after having deeply concentrated his attention on this subject, he marked on a map the line of a canal which was to pass through his country. Suddenly he saw a pamphlet, in a yellow covering, with this inscription: Project for opening a Canal through the Plain of Sologna (when proofs thus are read, it is evident what is passing in the mind); for some minutes, he read in it ideas which confirmed

* Do Rerum varietate, Lugd. t. viii. de 43, p. 410. See also Maisonneuve (Re'cherches et Observations sur l'Epilepsie, p. 295). This author speaks of a young epileptic, who sometimes amused himself by wishing to see some grotesque object, and scarcely did his imagination form it than it was faithfully pictured to his eyes.

† Du de1ire des Sensations, p. 94. Paris, 1846. 24 his own; the fanciful pamphlet then disappeared, and he resumed his work.*

M. Moreau, of Tours, has given in the Gazette des Hopitaux, the case of one of his patients who could instantaneously obtain hallucinations of sight; to effect which, he had only to incline his head a little forward. A very learned physician, who is a fresh example to us of the truth of the proverb: 'All is luck, or ill luck in this world,' relates that, being a prey to a nervous affection, which however left him the free exercise of his faculties, he became subject to occasional hallucinations of sight; but he perceived that they came when his mind dwelt on them. Curious to study this singular phenomenon, he several times daguerreotyped, as it were, the elements of his thoughts. They exhibited themselves to him in all the colors of reality, and remained an indefinite time. Having remarked that the constant repetition of these hallucinations caused him real uneasiness, he threw them off by an energetic effort of resolution.

Dr. M. M., whose intelligence and learning none can dispute, in referring to a communication on hallucinations, made known to the Medical Society of the twelfth arrondissement (at a meeting of the 6th February, 1847) that he could invoke hallucinations at will. At first the object was confused, like a cloud; by degrees it became more decided, and terminated in a very distinct apparition. In his lectures to his pupils, he could never so well describe the parts under observation as when, by a concentration of thought, he could give them the form of reality, and make them subjective, and his descriptions have much less lucidity when they are not thus naturally placed before him. He can easily dispel these colored impressions.

To these different facts we may add the hallucinations of ecstatics, of men who have concentrated their thoughts with great intenseness on one object; they are then evidently meditation perfected; and to suppose, as has been done, that in this case they succeed also the loss of attention, is certainly to be drawn into an error by a systematic idea. The opinion of Meister on the intermediate state between waking and sleep, establishes, however, a very important distinction, namely, that this state may be the occasion of deeds of the greatest consequence. Let us add, that a great number of hallucinations take place as well in the day as during the night. After all, if the weakening of attention be favorable to hallucinations, this explanation cannot apply to all cases, and in particular to hallucinations compatible with reason.

* Baudry, Essai sur lea Hallucinations, These, Paris, 1833, p. 17.

Tension of mind may, in a sphere much less elevated, and exercised under certain conditions, such as darkness, the silence of night, and complete solitude, create fantastic figures, and give a frightful aspect to trifles. We have already called attention to this fact. In nervous and impressible persons, whom education has not preserved from fearful and superstitious ideas, the brain is assailed with painful conceptions, which occasion them a sentiment of fear, sometimes even of terror. If, in this state, the eye be fixed on indecisive forms, instantly the phantoms of their imagination assume a bodily shape, and are transformed into real apparitions, which strike them with terror. How often, in the flickering light of a fire nearly extinguished, have we seen affinities to well-known forms, the resemblance to which have become more perfect in proportion as we have concentrated attention upon them! There is no doubt that the apparitions of persons long deceased are owing to this disposition of mind. The great doctors of divinity have rejected the reality of these visions, which are thus explained by hallucinations.

St. Athanasius maintains that when souls are disincumbered of their tenement of clay, they have no more communication with mortals. St. Augustine has remarked that if the souls of the dead could visit their friends, he was convinced that his mother, who had followed him by land and by sea, would appear to tell him what she had learned in the other world, and to give him good counsel.

It is easy to believe that when the brain is in this condition, imagination exerts its influence. Hallucination, adopts, in most individuals, the impress of their habitual ideas, and also rarely has for its object sensations entirely unknown to those who experience them. "Imagination," says Bernardin, "usually gives to them forms of which the person had already acquired a first idea, either by reading, tradition, or some other means. In some cases hallucinations are the exaggeration of the faculty which certain men possess of representing by thought images seen at an anterior period, or of clothing those images with new attributes.

How often, in fact, do we think we are hearing a melody which has impressed us agreeably !*

This opinion is upheld by M. Eusebe Salverte. "Imagination," says he, "combines received impressions, but creates none. In the phantoms of sleep, and the delirium of waking, nothing is presented which has not been seen, or felt, or heard. Terror, sadness, inquietude, and preoccupation, easily produce that intermediate state between sleeping and waking, in which dreams become real visions. Cassius Parmensis, proscribed by the triumvirs, fell asleep, a prey to fears which were but too well justified by his position. A man of frightful aspect appeared to him, telling him that he was his evil genius. Accustomed to believe in superhuman beings, Cassius doubted not the reality of the apparition. To superstitious minds, such a vision is the presage of a violent death, which a banished man could not long expect to avoid.

An analogous explanation will apply to the vision of Brutus on the eve of the Battle of Philippi.

Plutarch relates this celebrated apparition as follows: -