animals, but also quite as well, or at least less horribly, by disease. Any nerve connected with the anterior of divided, the will can no longer Any nerve attached to the pos

the spinal chord being act through that nerve. terior of the chord being divided, the mind can no longer perceive through that nerve. Hence the latter kind of nerves are called nerves of sensation, and the former, nerves of volition. Recent observation, however, has proved that volition and emotion exercise a constant influence, more or less marked, according to circumstances, even over those vital operations which we usually consider quite involuntary, such as breathing. This fact had been acted on by physicians long before the physiological rationale was discovered. They have been accustomed to force those persons who have swallowed large doses of opium, for instance, to walk about, and they have used violent means to excite the action of the will, because they well knew that unless the mind was roused to exertion, breathing would soon cease. But irrespective of volition, the muscles, subservient to the act of breathing, may be excited by impressions on the sentient nerves; thus, cold water, and other sudden or powerful excitants, occasionally applied, either in narcotic poisoning, or in mere faintness, rouse the latent nervous power, and keep the blood in motion until the cause of vital depression be removed.

Motion in an animal gives us the idea of the will being engaged to effect it, according to some demand made upon its feelings. Every act seems to imply an intention, and we have seen that will acts on the muscles

through the medium of appropriate nerves. But the same set of muscles may be caused to contract, even in the dead body, therefore it is plain that sensation and volition are not essential to their action. There is something in the muscle and nerve, ready to act when excited by a suitable stimulus, and this stimulus is directed into the muscle by the mind, or else the mind acts directly on the stimulus proper to each part.

Consciousness and will are both connected with the brain, and their influence on the spinal system of nerves in the human body is effected by the substance of the brain-matter being prolonged into the spinal chord, and mixed with its centre. Of course it follows from this fact that any disturbance in the connecting nervous organization, proportionally interferes with perception and volition. This may be strongly illustrated by experiments on the torpedo. If the brain of this creature be entirely removed, it does not attempt to protect itself, but if the smallest portion of brain be attached to the spinal cord it perceives the presence of any object near it, and becomes not only conscious of any injury, but is able to discharge its electrical battery the instant it is touched. Yet however sound the brain may be, if the continuity between it and the nerves supplying its galvanic apparatus be broken, it can no longer excite it or give a shock. A very small portion of brain is sufficient for the purpose of consciousness and determination, and even the absence of the entire brain does not hinder the manifestation of will and appetite. It is, however, necessary that the peculiar development of nervous matter

forming the summit of the spinal chord, called from its shape the medulla oblongata, should be preserved. The connexion of this substance with several of the nerves is of course essential, because the consciousness of objects and the action by which consciousness is evinced, require that the mental or perceiving power should be put in relation to the instruments of sensation and will. Some physiologists, however, have taken away the brains of animals slice after slice, destroying sense after sense, until they have removed the whole apparatus by which the muscles are actuated and the senses connected in subserviency to the mind, and when they have completed this mangling of God's creatures, finding that these no longer endeavour to resent the outrage or complain of the philosophic cruelty, the anatomists have complacently persuaded themselves that bit by bit they have discovered the being that felt, and pared it away with the scalpel till none remained; as if mind could continue to manifest itself without means. We see from M. Flouren's experiments, that as long as a single sense remained intact, with its nerve in connexion with a centre of action, so long perception and will were evinced, and surely, the existence of consciousness in any degree as plainly proves the presence of a conscious being as if all the instruments of speech and reason were in use, and the suffering subject of experiment or philosophic amusement could inform the groping dissector of all its feelings.

It appears that the perceiving and willing principle when impressed, operates upon a certain form of nervematter, which is of a grey colour and arranged in vesicles.

or little hollow grains in contact with the nerves, which consist of a white substance, forming a vast multitude of exquisitely fine tubes. We shall perceive how slight a derangement in the nervous apparatus is sufficient to disturb its functions, when we consider that a nerve-tube has a place in almost every visible fibre of the body, and that it is not larger than a silk-worm's thread, and may be distinctly traced in an unbroken line from the foot, for instance, up through the spinal chord to the base of the brain. Each nerve-tube is distinct and isolated, never transferring its stimulus to another of any kind, and experiments indicate that a nerve being impressed on any part of its course, it is equally affected throughout. Thus a man who has lost his leg will imagine he feels a sensation in his toe whenever the nerve which was once connected with it is irritated. The nervous power which traverses the nerve-tube is alike arrested by pressure on any part of it. Some theorists, who proceed in their visions beyond the region of bodily eye-sight, have propounded an explanation of nervous operation, which, as it originated in an endeavour to explain ghost-seeing in keeping with physiology, so, probably, it better comports with the imaginary than the real. They assert that a nerve-spirit pervades the body and acts as the direct medium of connexion between the soul and the nerves. Kerner, and other German physicians, account for some of the marvels of mesmerism by this intermedium, which, say they, is the power by which ordinary volition, sensation, and perception are effected. Ecstatic patients are reported to have seen this nerve-spirit pro

jected from an amputated limb, and occupying its place in all the plumpness of healthy proportion, so that as regards this luminous fluid there was no loss,-the spirit-limb, so to say, was still present. Since the rational experiments of Baron Von Reichenbach are before the public, we dare not ridicule the ideas thus suggested. But still this inconceivable organic power, taking the shape of the body, not being demonstrable to any sight but that of a very sensitive person- a ghost-seer, we may be excused from further reference to the matter, as it belongs to a department to which we do not yet aspire. The nerves are formed for the purpose of maintaining currents of power, and they are, in fact, circles of tubes that have no termination, but bend to return upon themselves, either in loops, or by forming a beautiful and continuous network. Each of these inconceivably delicate tubes is in some part of it invested by the grey vesicular matter before mentioned, and the nervous energy of any creature is generally in exact ratio with the quantity of this grey granulated substance in contact with its nerves, because, as it appears, this matter separates something from the blood, which is communicated to the nerves, or in some inscrutable manner energizes them. Man has more of this grey substance than any other creature in proportion to the size of his nerves, and it seems that he is indebted to this larger development, and abundance of vascular brain, for his power of maintaining attention in such a manner as is consistent with his moral and mental superiority, for by the will this matter is excited to convey stimulus to the