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them is another part called the infundibulum or funnel: the very names which these parts have received betray the total ignorance of anatomists concerning the offices which they perform.

SUBDIVISIONS OF THE HEMISPHERES.

The common subdivisions are into the CEREBRUM, the CEREBELLUM, the MEDULLA OBLONGATA, and the SPINAL CORD.

The spinal cord, (s. c. see plate 1st,) is contained within the vertebra, or back bone, and extends from the lower part of the back up to the medulla oblongata. It is considered by Mr. Charles Bell, as composed of three independent nervous columns, the ANTERIOR, the MIDDLE, and the POSTERIOR. (a, m, p.)

The anterior column Mr. Bell considers as the medium through which the brain acts upon the muscles to produce voluntary motion.

The middle column he denominates the respiratory column, because it sends branches to all the organs of respiration, and the other parts that must act in harmony with the lungs in speaking, laughing, crying, coughing, &c. He considers it as related to respiratory motion only, and not to sensation.

*

While I accord to Mr. Bell the merit of having first discovered that the spinal cord is composed of three columns,' I cannot admit that he has proved that the middle column is exclusively devoted to respiratory motions and the posterior to sensation. I doubt not that the principles unfolded in this work will lead to a more philosophical view of the true functions of these three columns and their relations to the brain and the body.

*See Eclectic Journal of Medicine for June, 1838.

Mr. Bell says that the "middle column stops short in the medulla oblongata, not being in function related to the brain," &c., (see Bell on the Nerves,) but I contend that it is as intimately and extensively related to the brain as either of the other columns; it being the medium of communication between the middle lobe of the brain and the digestive and respiratory organs. It not only, in my opinion, communicates motion to the respiratory organs, but it also communicates sensations of hunger, thirst, and suffocation to the brain.

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The posterior column, according to Bell, is composed of fibres that convey sensations to the brain. Thirty-one pairs of nerves are sent off from the spinal cord to different parts of the body, each of which has two roots, one in the anterior, or column of voluntary motion, and the other in the posterior, or column of sensation. As soon as these two roots leave the spinal cord they unite into one nerve and proceed on their way to the different parts of the body to which they are destined. These thirty-one pairs of nerves are remarkably regular in their origin, their succession, and their distribution; but none of their fibres, proceed from the middle column. Besides, there are ten pairs of what Bell calls irregular nerves, making in all, forty one pairs of nerves that proceed from the spinal cord.

The spinal cord, during the whole of its length, is about the size of a man's finger, but when it enters the skull, through the occipital hole, it gradually becomes larger until it reaches the brain; this part, therefore, between the occipital hole and the brain, is called the

MEDULLA OBLONGATA,

on account of its oblong form. This oblongata is considered as the grand centre of communication between all parts of the nervous system. It is the top or capital of the spinal

cord and joins it to the brain. It is the point where all the phrenological organs concentrate their united fibres.

If the brain may be compared to a rose, and the phrenological organs to its leaves, then the medulla oblongata will represent the top of the stem, where all the leaves originate and the spinal cord the rest of the stem.

The medulla oblongata has three prominences; one in the anterior part, corresponding with the anterior column of the spinal cord; these are named the pyramids, on account of their form; (the plural number is used to include both. hemispheres, as there is in reality but one in each hemisphere.)

These pyramids, Dr. Spurzheim considered as the origin of the organs of intellect, in the anterior lobe of the brain; and he traced the fibres by dissection, from the anterior column, or pyramids of the oblongata, to the anterior lobe of the brain. In the middle column of the oblongata are two eminences, (one in each hemisphere) which, on account of their fancied resemblance in shape to olives, have received the name of olivary bodies. I consider them as the origin of the fibres that constitute the middle lobe of the brain, and by dissection they may be traced into it.

In the posterior column of the oblongata are the two restiform bodies, (one in each hemisphere) so named on account of their resemblance to cords; these give origin to the cerebellum, and posterior lobe of the brain.

THE CEREBELLUM,

or little brain, occupies in the adult, about one seventh of the skull, and is situated in the lower back part, in such a manner as, when large, to give fullness to the upper part of the neck. It is entirely separated from the rest of the brain by a thin membrane called the tentorium, but is joined to the medulla oblongata by the fibres of the restiform bodies. The

cerebellum, is by phrenologists considered the organ of Amativeness, and notwithstanding its size would seem to proclaim its importance, no other use for it has been discovered, although it has been the subject of many experiments and conjectures.

THE CEREBRUM,

or brain proper, is by far the most important of the subdivisions, as it contains all the phrenological organs that have been discovered, except one. The cerebrum is with great propriety considered as consisting of three lobes in each hemisphere,

The ANTERIOR, occupying the forehead,

The MIDDLE, occupying the sides, and

The POSTERIOR, in the back part of the skull.

This is in remarkable agreement with the three columns of the spinal cord, the three eminences or columns of the medulla oblongata, and the three true commissures, which have been described.

Is it not strange that phrenologists have hitherto overlooked this evident division of the organs of mind into three classes?

VENTRICLES OF THE BRAIN.

Anatomists commonly reckon four cavities in the interior of the brain; one in each hemisphere, called the great lateral ventricles, and two in the median line, between the hemispheres, the foremost of which is the third, and the space between the cerebellum and cerebrum is the fourth. The third and fourth are too unimportant to deserve a particular description, as they are evidently mere accidental spaces and are probably not intended to subserve any very impor

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