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.

or brain

THE CEREBRUM,

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

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. T

versed, although it has been the subject many experimens quad evoolures,

THE CEREBRUM,

ad proper, is by far the most important of the suiit contains all the phrenological organs

a hovered, except one. The cerebrum is wil pety considered as consisting of three lobes a itere,

** AXATOR, occupying the forehead,

་་ ་

occupying the sides, and

et, in the back part of the skull.

kable agreement with the three columns the three eminences or columns of the the three true commissures, which

phrenologists have hitherto overst of the organs of mind into three

PNE BRAIN.

ve our cavities in the interior phere, called the great The de actan line, between the

was the third, and the

Cerebrum is the fourth.

*HQ*0/24pQt to deserve a parti

Key payer accidental spaces 105 arended to be any very impor

tant purpose: It is really surprising that they were ever dignified so much as to be classed with the great lateral ventricles. There is, therefore, in reality but one ventricle in each hemisphere; and even this is not strictly a cavity, as its upper and under surfaces are in contact. There is a thin membrane which lines the surfaces and prevents them from adhering to each other, and which at the same time supports a complicated tissue of blood-vessels that nourish the interior of the brain.

The mouth of each ventricle is towards the median line, so that when, in consequence of disease, water collects in one cavity, it flows out into the other of the opposite hemissphere; until in some extreme cases, the whole brain becomes distended like a bladder-the convolutions upon the surface are unfolded--the skull bones separate, and all the coverings of the head give way and grow larger to make room for the increasing contents, until the head assumes nearly twice the usual size.

The under surface, or floor of the ventricle, assumes a form, irregular and winding, in some measure corresponding to the three lobes. This appearance has been denominated tri-cornes, or three horns, on account of the ventricle extending its windings in three directions, anterior, middle and posterior.

In the fore part of the bottom of the ventricle is the corpora striata, or striped body-an eminence resembling half a pear with its largest end in the front lobe and its opposite end pointing outward and backward.

The optic thalami is another eminence larger than the striata and situated just behind it. It receives its name from the erroneous supposition that it is the origin of the optic nerve. Spurzheim considered the striata and thalami as composed of fibres on their way and expanding to form at last the convolutions at the surface of the brain. T

·

situation of these parts, concealed froni observation, renders their uses doubtful; the same is true of the fornix, a thin layer of medullary substance, that covers the thalami. There are also several other appearances, or parts in the ventricles which have received ridiculous and fanciful names, but nothing is known of their uses; such are the hippo-campus major and hippo-campus minor, &c.

SUBSTANCES OF THE BRAIN.

An examination of the surface of the brain shows it to be composed of a cineritious, or ashes colored substance, of a pulpy consistence, which seems to be almost entirely composed of a tissue of exceedingly minute blood vessels. If a cut is made so as to expose the internal substance of the brain it will appear of a cream color, or nearly white, and instead of being pulpy, like the cineritious substance, it is fibrous, and resembles in firmness and structure the nerves of the body. The cineritious substance is found in small quantities in the interior, but it is principally upon the outside, and surrounds the brain, as the bark surrounds a tree, and it has therefore been named the cortical or barklike substance.

The internal white fibrous substance is called the medullary substance.

It was the opinion of Spurzheim that the cortical substance was the nourisher of the medullary, but nothing is known with certainty on this subject.

CONVOLUTIONS OF THE BRAIN.

These are the folds, bounded by deep furrows, upon the external surface of the brain. It has been suggested that their use is to increase the surface of the brain without