writer of eminence, in Europe, maintains, that the brain is the organ of the mind, and that injuries of it impair the mental functions. Or does Antiphrenologist mean one who admits the brain to be the organ of the mind, but contends that the whole of it is essential to every mental act? then I request of him to reconcile with his theory the phenomena of dreaming, partial genius, partial idiocy, partial insanity, partial lesion of mental functions arising from partial injuries of the brain, and the successive development of the mental powers in youth. If Antiphrenologist means a person who admits the mind to manifest a plurality of faculties by a plurality of organs, but denies that Phrenologists have ascertained any of them, I ask him, Whether he disputes the three grand propositions, first, That dissection alone does not reveal functions; second, That reflection on consciousness does not reveal organs; and, thirdly, That mental manifestations may be compared with development of brain? If he denies these principles, then he is beyond the reach of reason; while, if he admits them, I would ask him to state what forms of brain, and what mental manifestations he found concomitant in his observations? because, until he shall make such a statement, his denial of the correctness of the observations of others is entitled to no consideration. But an Antiphrenologist, in any of these senses, has never yet appeared. The word, in its common signification, seems to indicate only an individual who is pleased to deny that Phrenologists are right, without knowing either their principles or facts, or having any pretensions to advance the cause of truth, by propounding sounder data or correcter observations of his own.

GENERAL VIEW OF THE FUNCTIONS OF THE SPINAL MARROW AND NERVES.

BEFORE entering on the discussion of the Brain, it may be useful to give a brief account of Mr CHARLES BELL'S discoveries of the functions of the Nerves. Dr SPURZHEIM, and many authors before him, very early published the conjecture, that there must be different nerves for sensibility and motion, because one of the powers is occasionally impaired, while the other remains entire. Mr BELL has furnished demonstrative evidence of this being actually the fact. He has also given due prominence to the philosophical principle, so urgently insisted on by Phrenologists, That, in all departments of the animal economy, each organ performs only one function; and that wherever complex functions appear, complex organs may be safely predicated, even anterior to the possibility of demonstrating them. The present section is derived from Mr BELL'S Anatomy and Physiology of the Human Body, vol. ii., 7th edition, 1829; and, in as far as possible, I have adhered to his own expressions. My object is to introduce general readers to a knowledge of his discoveries, which form parts of an extensive System of Anatomy, or of Philosophical Transactions, or of professional publications, which they seldom peruse. I shall omit all details necessary only for medical students, as Mr BELL's work is the proper source of instruction for them. Even the general reader will probably resort to Mr BELL's pages, after being informed of their interesting contents; he will find them clear, instructive, and most ably supported by evidence. Any errors or inaccuracies in the following condensed abstract, are chargeable against myself; for although in general I have followed Mr BELL's own expressions, the arrangement is greatly altered, and, occasionally, sentences of my own are introduced.

A nerve, says Mr BELL, is a firm white cord, composed of nervous matter and cellular substance. The nervous matter exists in distinct threads, which are bound together by the cellular membrane. They may be likened to a bundle of hairs or threads, inclosed in a sheath composed of the finest membrane.

The figure represents a nerve greatly magnified, for the sake of illustration, and consisting of distinct filaments; A, the nerve, enveloped in its membranous sheath; B, one of the threads dissected out. The nerves in thickness vary from the diameter of a small thread to that of a whip-cord. They are dispersed through the body, and extend to every part which enjoys sensibility or motion, or which has a concatenated action with another part.

The matter of a nerve in health, and in the full exercise of its influence, is of an opaque white; it is soft and pulpy, betwixt fluid and solid, and drops from the probe. When putrid, it acquires a green colour; when dried it is transparent. Corrosive sublimate and muriate of soda harden it; alkalis dissolve it. Each fibril of a nerve is convoluted, and runs not in a straight line, but zig-zag, like a thread drawn from a worsted stocking, which has by its form acquired elasticity that it would not otherwise have possessed. By want of use, the matter of a nerve is either not secreted in due proportion, or it changes its appearance; for the nerve then acquires a degree of transpa

rency.

There is no evidence that any fluid or spirit circulates in the nerves; nor is there any that the nervous fibrils are tubes.

Nerves are supplied with arteries and veins, and their dependence on the supply of blood is proved by the fact, that if a limb be deprived of blood, the nerves lose their powers, and sensibility is lost. If a nerve be partially compressed, so as to interrupt the free entrance of the blood into it, both the power over the muscles and the reception of sensation through it are interrupted; and when the blood is admitted again, painful tingling accompanies the change. It is not the compression of the tubes of a nerve, but the obstruction of its bloodvessels, which produces the loss of power consequent on tying it. The brain, the nerve of the eye, the ear, the nerves of sense and motion, are all affected by the change of circulation; and each organ, according to its natural function, is variously influenced by the same cause -the rushing of blood into it, or the privation of its proper quantity.

A nerve consists of distinct filaments; but there is nothing perceptible in these filaments to distinguish them from each other. One filament serves for the purpose of sensation; another for muscular motion; a third for combining the muscles, when in the act of respiration. But the subserviency of any of all these filaments to its proper office, must be discovered by following it out, and observing its relations, and especially its origin in the brain and spinal marrow. In their substance there is nothing particular. They all seem equally to contain a soft pulpy matter, enveloped in cellular membrane, and so surrounded with a tube of this membrane as to present a continuous track of pulpy nervous matter, from the nearest extremity in the brain to the extremity which ends in a muscle or in the skin.

The key to the system will be found in the simple proposition, that each filament or track of nervous matter has its peculiar endowment, independently of the others which are bound up along with it; and that it continues to have the same endowment throughout its whole length. There is no interchange of powers betwixt the different filaments;

but a minute filament of one kind may be found accompanying a filament of a different kind, each giving a particular power to the part in which it is ultimately distributed. Some nerves give sensibility; but there are others, as perfectly and delicately constituted, which possess no sensibility whatever. Sensibility results from the particular part of the brain which is affected by the nerve. If the eye-ball is pressed, the outward integuments feel pain, but the retina gives no pain, only rings of light or fire appear before the eye. In the operation of couching the cataract, the needle must pierce the retina; the effect, however, is not pain, but to produce, as it were, a spark of fire; and so, an impression on the nerve of hearing, the papillæ of taste, or any organ of sense, does not produce pain. The sensation excited has its character determined by the part of the brain to which the nerve is related at its root. But there are nerves which have no relation to outward impression. There are nerves purely for governing the muscular frame, these being constituted for conveying the mandate of the will, do not stand related to an organ of sense in the brain; hence no sensibility and no pain will be produced by them. Each of these may be said to be a nerve of exquisite feeling in one sense, that is, it may be a cord which unites two organs in intimate sympathies, so as to cause them to act in unison; yet, being bruised or injured, it will give rise to no perception of any kind, because it does not stand related to a part of the brain, whose office it is to produce either the general impression of pain, or heat, or cold, or vision, or hearing: It is not the office of that part of the brain to which it is related to produce perception at all.

At the conflux of the nervous filaments, small reddish tumours appear, which are named GANGLIONS (See D in fig. p. 61). A ganglion resembles in form the circular swellings which appear on the stalk of a straw or of a cane; but ganglions do not rise at regular intervals on the nerves