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SEAT OF PARTICULAR FACULTIES.

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To mental operations, the cerebrum and the cerebellum. To the senses of hearing, seeing, smell, and taste, the medulla oblongata. To voluntary motion and general feeling, including the sense of touch, the medulla spinalis. To the thoracic and abdominal viscera, the sympathetic nerve.

Des Cartes, in his treatise on the passions, gives it as his opinion that the mind exercises its functions in a small gland, placed over the communication between the cavities of the brain-that the slightest movement in this gland affects the animal spirits, and that it is equally susceptible of the movements of these spiritsthat the mind has as many different perceptions as there are different movements in this gland--that, by the influence of the mind exerted upon it, the animal spirits are impelled into the pores of the brain, whence, by the nerves, they are carried to the muscles, or contractile parts of the body. Des Cartes founds his opinion upon the fact, that all the other parts of the brain are like the organs of the senses, double; and as we can have but one single idea of any object at one and the same moment, it is necessary that there should be one part in which both images, coming from double organs of the senses, meet or unite, before reaching the mind, to prevent the confusion of ideas which the receipt of two objects, instead of one, would produce; and that there is no other part in the whole body where it is possible for them to be so united, except in this very gland.

The other theories on this subject, that may be

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SEAT OF PARTICULAR SENSES.

briefly alluded to, are those of La Peyronie, who places the seat of the mind in the fornix; Richerand, in the annular protuberance; Willis, in the corpora striata; Sömmering, in the fluid of the ventricles; Digby, in the septum lucidum; Lancisi, in the corpus callosum; and Van Helmont, in the pylorus ventriculi. D'Assigny, in his treatise on memory, conceives the seat of this faculty to be the cerebellum, because persons who have a capacious memory, have the hinder part of the head larger than ordinary; and that the lateral ventricles are the seat of imagination. and reason.

Camper, about the year 1770, appears first to have considered the intellectual faculties to be connected with the anterior portions of the brain, and he states the two extremes, of what he has termed the facial angle, to be 70° and 100°; namely, from that of the Negro, to the fully-developed forehead of the Grecian Apollo.

Gall, from observing prominence of the eyes to be connected with excellence of memory, conceived that other mental faculties might have external indications also; and that the manifestation of these faculties, and the influence of appetites and passions, are connected with the comparative proportions of the different parts of the convolutions of the brain-that these convolutions are to be considered the expansions of internal nervous bundles, the size of which he thought could be ascertained, although the organs be not confined to the surface-and that the greater or less

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energy of those faculties and propensities, were indicated by the proportions of corresponding parts of the skull. He pointed out, in the brain of man and of other animals, the organ of each propensity, feeling, and intellectual power, amounting, according to him, in man, to thirty-three in each hemisphere. Some of his disciples, however, have added considerably to this number.

Walker, on the other hand, says that he can discover no vestige of any corresponding organization for the thirty or forty little functions of the craniologists. According to him, memory and association are connected with the convolutions; the combining faculties, chiefly with the anterior and superior part of the brain; the comparing faculties, with the middle and inferior part; and the determining faculties, with the posterior portion of the brain and cerebellum.

Dr. Scipio Pinel has lately published a work, in which he contends that the sensations (the source of the other mental faculties) are impressed, or engraved on the lamellæ, or leaves of the convolutions of the whole surfaces of the hemispheres, in such a way as to be capable of being found again, and revived, even after the lapse of many years that they are engraved on these lamellæ, on which they remain like the images on plates subjected to the daguerreotype process, and perhaps by means of a very analogous mechanism. The cineritious portion, he regards as simply an organ of nutrition of nervous substance.

In reference to all these preceding opinions, I would

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observe, that it seems, at first sight, a probable-enough conclusion, that divisions so well marked as those of the cerebrum, cerebellum, and medulla oblongata, may be appropriated to perform distinct functions. Even this, however, as far as I am aware, has not yet been satisfactorily proved. And, although we have not any reason to consider it improbable that the different modes of manifestation of the mind, may be more connected with certain portions of the brain than with others; yet, in all the opinions respecting phrenology, much more is assumed than there are sufficient data to authorize; the propositions in which they are conveyed are vague and indistinct, and they will not bear that strict and logical analysis, which has been considered indispensable in philosophical inquiries.

CHAPTER IV.

THE INTELLECTUAL FACULTIES.

THE phenomena of mind have been variously arranged into those of

INTELLECT AND VOLITION.

INTELLECTUAL AND ACTIVE POWERS.

SENSATIONS, THOUGHTS, AND EMOTIONS.
INTELLECT, SENTIMENTS, AND PROPENSITIES.
ANIMAL POWERS, INTELLECTUAL FACULTIES,
AND MORAL POWERS.

FACULTIES OF UNDERSTANDING, ELECTION,
EMOTION, &C., &c.

The difficulty of forming a satisfactory arrangement will appear from the variety that has been proposed. The first of the above, and the oldest, is, I believe, the one most generally adopted; and for that reason, although open to objections, is here followed.

Before entering upon the consideration of the mental faculties, it may be as well to remind you, that the external senses are the media through which impressions are conveyed to the brain, where an idea, or

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