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The ANATOMY of the Brain, with a General View of the
Nervous System, by G. SPURZHEIM, M.D. &c., translated from an unpublished French MS. by R. Willis, Member of the Royal College of Surgeons in London, with eleven plates, pp. 233.-London, Highley; Edinburgh, Hill and Son.
We are glad to inform our readers, that Dr Spurzheim has at last presented the English public with an account of the anatomy of the brain in the very accessible form of a moderate-sized octavo, written in their own language, and illustrated by numerous excellent lithographic plates, many of them reduced copies of those which have contributed so much to the celebrity and usefulness of the great French work published under the joint names of Dr Gall and himself, and which has given not only an immense impulse but A RIGHT DIRECTION to the examination of the structure and functions of the nervous system in general. On the continent of Europe the result of their labours is now everywhere conspicuous in the silent adoption of their anatomical views by the most distinguished teachers and authors of the present day, and in the increasing attention which is everywhere paid to the discovery of the functions of the brain. There, as here, the real authors of the change may industriously be kept out of view, or the change itself be imputed to a different cause, by those who prefer appropriating the discoveries and ideas of others to the magnanimity of avowing the source from which they have derived them; but the great object is attained, the range of science is extended, and, sooner or later, history will pronounce judgment, and give the honour to whom it is really due.
As an anatomist, Dr Spurzheim ranks among the highest authorities of the present day. His labours have contributed
in no ordinary.degree to unfolding the true structure of the brain, and to the discovery of the successive additions which it receives as we ascend in the scale of the animal creation. We wish we could stop to particularize what he has accomplished apart from Dr Gall; but for the present our limits oblige us to confine ourselves to the following quotation from his preface, and to pass on without comment to the subject matter of his treatise.
“Having completed my studies in 1804, I was associated with “ Dr Gall, and devoted myself especially to anatomical inquiries. “ At this period Dr Gall, in the Anatomy, spoke of the decussa“ tion of the pyramidal bodies, of their passage through the pons “ varolii, of eleven layers of longitudinal and transverse fibres in " the pons, of the continuation of the optic nerve to the anterior
pair of the quadrigeminal bodies, of the exterior bundles of the
crura of the brain diverging beneath the optic nerves in the di“ rection which Vieussens, Monro, Vicq d'Azyr, and Reil had “ followed, the first by means of scraping, the others by cutting the “ substance of the brain. Dr Gall showed further the continuation “ of the anterior commissure across the striated bodies ; he also “ spoke of the unfolding of the brain that happens in hydrocephalus. “ The notion he had conceived of this, however, was not correct; “ for he thought that the convolutions resulted from the duplica“ ture of a membrane, believing that the cerebral crura entered the “ hemispheres on one side, expanded there, and then folded back
on themselves by the juxta-position of the convolutions. The “ true structure of the convolutions, and their connexion with the “ rest of the cerebral mass, were not described until our joint Me“ moir was presented to the French Institute in 1808.
“ The mechanical direction which the anatomical investigations “ had taken did not appear to me satisfactory. Guiding myself in
my inquiries by physiological views, always comparing structure « with function, I discovered the law of the successive additions to the “ cerebral parts; the divergence in every direction of the crural "bundles towards the convolutions; the difference between the “ diverging fibres and those of union; the generality of commis
sures; the true connexion of the convolutions with the rest of the “ cerebral mass, and the peculiar structure which admits of the “ convolutions being unfolded (an event which occurs in hydroce“ phalus of the cavities), whilst the mass lying at their bottoms, “ and belonging, for the most part, to the apparatus of union, or of " the commissures, is pushed by the water between the two layers “ composing them; lastly, I 'demonstrated the structure of the “ nervous mass of the spine, and I flatter myself with having ar“ rived at the best method of dissecting the brain, and exposing its “ parts."-P.11.
The first section of Dr Spurzheim's work is occupied with the consideration of the two substances of which the nervous system is composed. The one is gelatinous or pulpy, and usually of a greyish or brownish hue, and is generally called the cortical or cineritious substance; the other is fibrous, and of a more or less perfect white colour, and is called the white, medullary, or fibrous substance. Pulpiness, and not colour, is the distinguishing character of the former, and, from inattention to this, some anatomists have maintained that the white or fibrous substance may exist without the pulpy. There are animals, for instance, whose humours or blood is white; but the existence of a circulating fluid is not on that account altogether denied. In the same way the pulpy substance varies in complexion in different species of animals and even in the same species. It is very pale in those who die of consumption or dropsy.
In the mammalia the pulpy substance occurs on the surface of all the convolutions of the brain and cerebellum, in the striated bodies and optic thalami, in the interior of the crura cerebri, annular protuberance, corpus dentatum, cerebellum, medulla oblongata, and spinal cord, and in all the ganglions of the body, and is always in connexion with the fibrous substance. It has an immense quantity of bloodvessels distributed through it, but its true structure is still unknown.
The white or nervous substance is essentially fibrous, as was maintained by Lewenhoeck, Vieussens, and Steno. This may be made evident by scraping a recent brain, or by maceration in alcohol or acids. From the uniform concomitance and proportion observable between the two substances, and from the pulpy preceding in existence the fibrous matter, Drs Gall and Spurzheim were led to consider the former as the source of the latter. By this they do not mean to assert that the one grows out of the other, but only to announce the fact of a gelatinous and greyish state of the brain preceding its fibrous and white condition, in the same way as bone begins by being gelatinous, then cartilaginous, and ultimately solid and earthy. The essential circumstance, however, is the fact that the fibrous does not exist without the pulpy, and that the one is proportioned to the other. As to the distinctive uses of each little is known.
After showing that the brain does not give origin to all other parts of the nervous system, Dr Spurzheim lays it down as a first and most important anatomical principle, that the nervous system IS NOT AN UNIT, BUT CONSISTS OF
MANY ESSENTIALLY DIFFERENT PARTS, WHICH HAVE " THEIR OWN INDIVIDUAL ORIGINS, AND ARE MUTUALLY IN
COMMUNICATION;" and, in relation to this principle, he proceeds to treat, Ist, Of the mode in which the individual parts of the nervous system are formed. 2d, Of the order of development of these parts; and, 3d, Of their reciprocal relations.
Dr Spurzheim proceeds in his second section to prove that, in accordance with the above principle, the nervous system must be divided into different masses, and to show that the division most in harmony with nature is that adopted by Dr Gall and himself; comprehending, 1st, The nervous masses essential to motion and to the five senses; and, 2d, Those composing the organs of the affective and intellectual functions. All these parts are independent of and not proportioned to each other, and any one may exist or be wanting without affecting the remainder ; and this is the only test of nature having erected the limits.
The third section, therefore, treats of the nervous masses of voluntary motion, and of the external senses, including the spinal cord, with its nerves, and those of the head commonly styled cerebral.
The spinal nerves are destined to the functions of feeling and voluntary motion; the cerebral, or more properly the cranial, are less voluminous, and subserve not only voluntary motion, but taste, hearing, sight, and smell. Dr Spurzheim often insisted on the necessity of sensation, motion, and every other primitive function having a distinct apparatus, however much they may apparently be confounded together; and he instanced the case of the three branches of the fifth pair, all seeming to arise from one root, and yet one being the nerve of taste and the others of motion. Since that time Mr Charles Bell endeavours to prove, by the force of facts, that every part receiving more than one nerve performs more than one function, and that a new nerve is supplied for every additional function. He has shown also, that the portio dura, or facial nerve, long supposed to minister to sensation in common with other nerves, conveys no impression of pain when cut or torn, but serves only to place the parts on which it is ramified under the influence of the respiratory motions. Lesions of the fifth pair, on the contrary, produce pain, and the parts on which it is ramified become insensible when its branches are cut across.
After noticing the experiments of Magendie and others in proof of sensibility depending on the dorsal, and motion on the abdominal roots of the spinal nerves, Dr Spurzheim says, “I do not believe that the only office of the spinal cord, with its “ nervous roots, is to establish a communication between external
impressions and the brain, and between the brain and the instru“ments of motion, the muscles. To me it seems probable that a « very small part of the spinal cord suffices for these purposes ; " the particular portion, or organ, however, cannot, in the present * state of our knowledge, be specified.” “I rather conceive that “they (the spinal cord and nerves) aid in maintaining the powers * of those parts to which they are distributed; for instance, that the “muscles, or instruments of motion, acquire their power, in fact, “ through the influence of their nerves, whilst the will to make the “ muscles act resides in the brain."-P. 46. But the subject, he adds, is still involved in much obscurity.
In regard to the structure of the spinal cord, Dr Spurzheim remarks, that it is composed of two similar halves, one on each side of the mesial plane. These halves are parted to a certain depth by two longitudinal clefts, the one deep, but not conspicuous, on the dorsal, and the other shallow, but conspicuous, on the abdominal surface, and are united between these fissures by a commissure or apparatus of union.