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1850.]

Organology of the Brain.

Over the location of each convolution the amount of Nervaura evolved or amount of effect produced by it, makes it easy for the impressible to recognize the spot: where instead of these convolu tions the intervening space and its membranes alone are subjacent, it is easy to recognize the absence of that influence. In this manner I have often had the location and boundaries of convolutions pointed out upon the head by tracing carefully the lines of no impression or course of the membranes which line the sulci between the convolutions.

Where the head is covered with hair it is difficult to learn these lines and boundaries, although it is not impracticable to trace them. I have often wished and designed to induce some bald person, or some one who would submit to shaving off the hair, to sit for examination and have these lines-the boundaries of the convolutionstraced and marked upon the head; I still expect to do it.

In this manner we might make an anatomical or convolutional arrangement of the organs, which would be very good, but as this has not been done we have other considerations to guide us.

The number of the organs or divisions recognized should not be greater than necessary, for they would fatigue the memory and obscure the subject. It is difficult to obtain a good periscopic view of a science unless we generalize and reduce the number of details. But if the number of organs is too much reduced, many important facts will be kept out of view and the recognized functions will be inadequate to explain the varieties of character and temperament. When we generalize too much, we cannot find adequate terms. The names of organs will not cover half of their functions. Thus if we had so large an organ as to occupy entirely the old location of Cautiousness, we could not find a word to express all its functions-Sanity, Restraint, Coldness, Cautiousness, Sleep, &c., are ideas which no one word could express.

In arranging our organs, we should pay regard to the natural division of our faculties and passions as they are already recognized by mankind, and to the arrangement of the English language. If any faculty or passion is a matter of universal remark, and a simple word has been devised to express it, that faculty and word should not pass unnoticed. It would be a great omission, for instance, if we did not find an organ of Memory and fix its proper place on the bust. So we may say of Sagacity, Judgment, Reason, Imagination, Hope, &c.

Whenever we find a word sufficiently generic to comprehend all the manifestations of the different fibers of a portion of the brain, we deem it proper to recognize that region as one organ, and express its function by that name. The word Language, for instance, will comprehend all the manifestations of one small convolution, and "Calculation" will comprehend all the powers of another. Thus our names may be comprehensive and convenient, being

nearly the same as would be adopted if we took the divisions of convolutions for the basis of our arrangement.

In our nomenclature we have no technicalities. We find the current English language entirely sufficient without coining new terms. For language is the expression, the embodiment of huma nity-the utterance of all that is common to the human race. It is the representative of the common stock of mentality. And if there be any idea not sufficiently distinct or familiar to have demanded expression, if there be any passion so rare and uncertain as never, among countless millions of beings, to have been the subject of observation and conversation to many, and hence never to have found its way into language, it cannot be a matter of great importance in the history and philosophy of the race.

Language, the representative of thought and character, is the picture, or rather the shadow, of man-the brain is the center of the man. Language then corresponds to the brain as the shadow to its cause. If we transfer the English language back to its origin in the brain, we will find an appropriate location for every word expressive of human passions or faculties. We will find that ele ments of character which have at all times attracted attention and comment, such as Hope, Pride, Courage, Reason, Memory, Anger, Justice, &c., belong to definite and easily ascertained portions of the brain. Thus the whole anthropological vocabulary will be

located on the convolutions.

The names of our organs then will need no definitions or explanatory essays, for the exact meaning and whole force of such terms are well settled and well known. Formerly the names of phrenological organs were continually misleading from their inadequacynow the names can be made to embody and give precision to the science. The great increase of our knowledge, instead of rendering Phrenology more complicated, renders it more simple. Thus it is with all sciences. Complete and accurate knowledge is easily comprehended. It is only superficial and fragmentary knowledge which wearies the learner and appears tediously obscure. The unfinished sketches of a tyro in drawing may be difficult to comprehend, but the pictures of a master strike every eye at a glance, and need no explanation. Science is a picture of Nature-the partial and misty glimpses, which are first sketched in cultivating any science, are far more embarrassing to the memory and understanding, than the full, bright, diversified view which we obtain when all the clouds are removed and everything is distinctly seen.

The convolutions are generally composed of groups of fibers of congenial functions, easily classed together, and much more conge nial than those of any two distinct convolutions. The arrangement which we have adopted corresponds, it is believed, to anatomy. On the side of the head, instead of making a few large organs which run from the front backward across several ranges of convolutions, our organs run down from the coronal region in a

somewhat oblique manner, as you see the convolutions do in the brain.

I was not led into this arrangement by anatomy, but by finding that it was the only rational mode of classifying the functions, and the fact that it corresponded to anatomy gave additional assurance of its propriety.

Before I discovered cerebral impressibility I entertained similar views to those which I have just stated, and therefore dissented from the Gallian system of Phrenology.

Whoever would reason well upon this subject might arrive at such conclusions a priori. Let me rehearse the views and arguments which I publicly presented, long before I had made any experiments upon the brain.

"It is a simple and undeniable principle, that whatever we believe in regard to the physiology of the brain must be in harmony with its anatomy. Every part of the body that has a distinct and peculiar function has a distinct and peculiar structure. A muscle is different from a nerve-a bone is different from both, a tendon is different from either, and a mucous membrane is different from a serous membrane; a vein is different from an artery in structure and position; the lungs differ from the liver, and the heart is still more different from each. Each nerve also has a peculiar structure in itself, and whenever a nerve is different in its function from any other nerve, the microscope will show that the structure is different. But when we find the structure the same, we conclude the function to be the same-thus bone is bone all over the body. It has nearly the same appearance and answers about the same purposes; voluntary muscular fiber is nearly the same thing all over the body, and is very similar in different animals-its function is to contract forcibly, and this is the only function that it ever has, anywhere. The dif ferent parts of a muscle present the same appearance having precisely the same function. So when we look along the cord of any one nerve we find its structure the same all along its course. But if we examine parts of different nerves we find their structure and connections different.

"Anatomists, therefore, when they find two parts of the body with precisely the same minute structure, know that their functions are about the same whenever the structure is evidently different, they know that the functions must be different.

"In the encephalon, for instance, the structure of the cerebrum is very different from that of the cerebellum, and it is, therefore, very evident that they must perform different functions. The structure of the front and that of the posterior lobes are different-the fibers constituting the intellectual organs are more delicate than those of the animal organs. This is just what we should expect. The intellectual organs are delicate and rapid in their action. In one second I can look round a room and conceive distinctly twenty persons-we can look over a landscape in a moment and conceive

instantly at least 1000 objects-on a clear starlight night we can at one glance of the eye see more stars than we could count in the whole night. The action of thought is thus quicker than lightning. The action of our animal passions is much slower-if we get angry we are slow in recovering, all our feelings are slow, it is natural then that they should act by organs of a coarser texture.

"The great regions of the brain lie in different positions and have different forms-hence we may easily conceive that the great divisions of the head, laid down in Phrenology, will be the organs of different faculties. But when we come to very minute divisions and organs accurately defined, we find that the brain is not divided in a corresponding manner. We find that the convolutions run about in an irregular style, like the intestines, and run together in every direction, without any precision. We find that the develop ments which modify the form of the skull are often quite different from the forms of the organs laid down on the bust-the develop ments of the head occur in so promiscuous and irregular a manner, that it is evident Nature is not subject to that exact arrangement and division which phrenologists adopt.

"Omitting the cerebellum we cannot take any part of the cere brum and there pick out a particular organ from the mass-we cannot trace exactly the boundaries of any one organ, because every organ is connected with its neighbors. We cannot by the nicest inspection of a convolution say at what point one organ terminates, or at what point another begins. It is true there are furrows or sulci between the convolutions, but these do not correspond to the present divisions of organs. An organ consists sometimes of one convolution, but generally of more, and in all cases the convolu tions so run together that the idea of division between them is alto gether arbitrary. Now portions of the brain thus almost identical -with fibers mingled together, running parallel and of essentially the same structure, as far as we can discover, must have similar functions. If we assert that two similar and equal fibers running parallel in the center of an organ have the same function, we have equally good reason for believing that similar fibers, lying together parallel and contiguous in another part of the same convolution, are equally identical in function.

"If we take any one convolution it would be presumptuous for us to assert that there is a total difference of function in any of its adjacent parts, unless we could trace the line of distinction, or discover some difference of structure. It was probably some such view as this that led Dr. Spurzheim to say, 'The organs of analogous powers are regularly in each other's vicinity; the convolutions that compose them even run into each other.'

"If then we view the brain anatomically, we find reason to consider it an organ of blending functions-we find that all the organs run into each other in the most insensible manner, and there is no point at which we can draw the line of distinction between its

parts. Physiologically we have a still stronger certainty. It is a law of physiology, that similar organs sympathize in their functions. and that the whole body has a sympathy together. The parts that most resemble have the strongest sympathy, and those that are nearest have a still stronger sympathy, called the sympathy of continuity. In the brain the adjacent fibers have the sympathy of similarity, and also the sympathy of continrity. No portion ever becomes excited without the adjacent parts immediately participating in that excitement-the action must extend, and action in the brain is always diffusive. Any vigorous impression upon the brain of the sleeper, through the senses, diffuses itself until the whole brain is waked up. And whenever action is thus set up in any part of the brain an increased determination of blood immediately occurs. Now adjacent portions are supplied by expansions of the same artery, and by continuations of the same capillary vessels; in their action then they must go together, for whenever an increased determination occurs to one, the other receives it also, and must be in the same manner stimulated to increased action. Whenever any organ is excited we thus excite all its neighbors and develope similar faculties to co-operate in the act.

"The brain, then, is so situated that if we put our finger upon it at any one point, and find a particular function, we may pass along the convolution and find the function gradually changing into one of a different character, which, as we progress, continues to change. until a character or function totally opposite is found in the opposite quarter of the brain. If we take any two positions in the brain, of distinct functions, the point between them will present a function of intermediate character. The functions of the various parts are then like colors of the prismatic spectrum, capable of being classified into certain distinct species, but all so blended that it is difficult to draw an accurate line between them."

This beautiful blending of functions, like the colors of the rainbow, which I thus inferred from the truths of anatomy and physiology, is now established by experiment. Yet to my mind the argument in its favor is so complete a demonstration, that nothing but experiment could have increased my confidence. So far as I have yet examined this subject it appears that this blending of function takes place along the range of each convolution, but not in passing from one convolution to another. In crossing the sulcus the change appears more abrupt and decided.

In grouping the organs we may consult our convenience. The division of moral, intellectual, and selfish is common and proper, but we cannot draw any division lines that will be unobjectionable, for the blending of functions along the boundary lines is such that many organs appear to occupy a neutral ground and cannot be decidedly classed with either of the divisions that we make.

A very convenient division may be made by drawing a line between the organs which are decidedly good in their tendency and

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