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they who believe it will endure no error.” That Reinhard strenuously insisted on the atonement by a divine Saviour, and on faith in it as the indispensable condition of salvation, his discourses furnish abundant evidence. The longer he lived, so much the more evangelical became his style of address. His later sermons have less of the distinctively ethical, and more of the strictly religious character. His errors were those which the circumstances in which he wrote, would naturally incline him to adopt; and instead of complaining that he did not cordially defend some truths which we prize, we should rather be grateful that he emerged from the spiritual darkness of his age, and stood forth the champion of a down-trodden and essentially evangelical creed.
OF THE DEPENDENCE OF THE MENTAL POWERS UPON THE
By George 1. Chace, Prof. of Chemistry and Geology in Brown University.
Few subjects are fitted to awaken a more lively interest, than the mysterious connection subsisting between the body and the spirit. Though entirely distinct from one another, and constituted, as there is reason to believe, of essentially different elements, they are bound together by the closest ties, and sustain throughout the most intimate relations. Neither is able to withdraw itself from the other, or can act independently of the other, or has any power except through the other. Any disorder of the body immediately affects the mind, and any derangement of the mind as quickly extends its influence to the body. This wonderful union, and, as it would almost seem, blending of the material and spiritual in our naturcs, has commonly been regarded rather as a theme for the exercise of the imagination and fancy, than as a subject for sober investigation; and the ideas formed concerning it have been expressed more frequently in the vague and figurative language of poetry, than in the precise terms of philosophy. They have moreover been as various as the different aspects of the connection to which they relate.
Some of the ancients looked upon the complex frame of mind and body as a kind of musical instrument, and regarded the different nerves as so many keys to whose mysterious touch the soul gives out 1849.]
Organic Conditions of Mental Phenomena.
its beautiful harmonies. Others saw in the body a prison, in which the spirit is incarcerated, and from which it can look out upon the world only through the narrow windows of the senses. But for the barrier opposed by the dark walls, which shut it in on every side, they supposed the range of its perceptions and knowledge would be much wider. Remove that, and the soul would be all eye, and all ear, and the intellect pure intelligence. In the Second epistle of Paul to the Corinthians, and in the General epistle of Peter, we find the body spoken of under the figure of a tabernacle or house, fitted up indeed with various accommodations for the temporary residence of the spirit, but destined after a few years to be exchanged for a more glorious habitation, “ a house not made with hands, eternal in the heavens." In later times, since the structure and functions of the several parts of the bodily frame have been better understood, it has more commonly been regarded as a very complex machine, embracing numerous contrivances, adapting it on the one hand, to the powers and susceptibilities of spirit, and on the other, to the endowments and capacities of matter—a specially constituted medium through which these two forms of being, although in nature so widely removed from one another, may notwithstanding hold intercourse—a skilfully constructed instrument whereby the soul is enabled to impress its volitions upon outward existences, and these in turni can act upon the soul.
Within few years past, there have arisen those who suppose, that besides establishing a communication between the mind and the external world, the body also furnishes in the brain, organs through which the different mental powers are exercised. They believe that not only the intellectual faculties, but also the sentiments are dependent in their manifestation upon these organs, in the same manner as the several bodily functions are dependent upon the parts respectively ministering to them; and as in the latter case, they imagine the vigor of these faculties and sentiments to be proportional to the development of the particular regions of the brain, with which their manifestation is connected, and moreover capable of being determined by the external indications of such development.
Without stopping to inquire how much of truth there may be in these or any other ideas that have been advanced in respect to the relation subsisting between the spiritual and the corporeal nature of man, we proprose to trace the organic conditions of the several classes of mental phenomena so far as it may be done in the present state of physiological science, and see what light these throw upon the subject. We shall commence with the phenomena which are most immediately and most obviously connected with the body-the various forms of sensation. All of these, of whatever character they may be, whether pleasurable or painful, whether designed for the protection of the body or for the conveying of information to the mind, are directly dependent upon the nervous system, the only part of the organization in immediate relation to the spirit-the only part upon which the spirit is capable of acting, or through which it can receive impressions from the outward world. The connection of the other parts is solely through this. By themselves, the bones, muscles, and integuments, the organs of the several senses, the heart, lungs and stomach have no more lise, no more sensibility, no more power of motion than any foreign matter. It is the nerves alone that endow them with these properties—that put them in communication with the spirit, and thus render them available for the different purposes which they are designed to accomplish in the living economy. In prosecuting an inquiry, therefore, designed to throw light upon the organic conditions of the mental phenomena, we need not extend our researches beyond the nervous system, as all without this is necessarily excluded from any direct agency in their production.
All our sensations, have their remote origin in impressions made upon the outward senses. These impressions, however they may be produced, whether by the contact of solid bodies or by the vibration of aeriform fluids or by the impulses or undulations of still more subtle media, give rise to some kind of action-its precise nature has not been determined-which is propagated along the filaments of the nerves, until arriving at their termination in the brain, it passes to the spirit. By a law of our constitution, the sensations thus awakened although really in the mind, are referred either to the parts of the body where the impressions in which they originate are made, or else to the external objects which are the cause of these impressions. Such a reference of them is necessary in order that they may accomplish the objects for which they are intended—the protection of the body and the imparting of knowledge to the mind. Did not the pain occasioned by too great heat or too great cold or by undue pressure or by any of the other causes from which we are liable to suffer, direct our attention to the part affected, it would be of little service in enabling us to avoid the threatened injury. The same is true of the suffering attendant on disease. Did we conceive of this, only as an affection of the spirit, it would afford no indication as to the nature or situation of the disorder, and no guide as to the proper means for remedying it. The sensations connected with the eye and ear, on the other hand, being designed for the sole purpose of awakening in the mind a knowledge of external existences, are uniformly referred to objects without ourselves. 1849.]
Relation of the Brain to the Mind.
The different shades of color, whether from instinct or through the power of habit formed at a period too early for its origin to leave traces in the memory, are constantly regarded by us as attributes of the bodies which reflect the rays immediately producing them. Nay, we necessarily conceive of them not only as external to ourselves, but as having actual extension—as spread over the surface of those bodies, in the same way as the sensations designed to protect our corporeal frames seem to extend through the parts in which we imagine them to be situated. And yet, it is obvious upon a moment's reflection, that no two things can be more unlike than the state or affection of the spirit produced by the impinging of the different colored rays upon the optic nerve, and that physical condition of the surface of bodies which determines the reflection of those rays. They are as wholly dissimilar as the sensation of heat, and the substance which evolves the caloric producing it; or as the sensations of smell and the bodies which exhale the odors awakening them; or as those of touch and the material forms whose contact and pressure excite them. The same general observations apply to the ear. The sensations which we experience through this organ seem to be wafied from the distant body whose vibratory movements, propagated through the intervening air, are the immediate agent in their production. Neither the distant body, however, nor the atmospheric undulations proceeding from it, bear any resemblance to sound. . This, like color, is merely a sensation in the mind, which from long habit we have come to associate so closely with its outward cause, that we cannot even in imagination separate them. In a similar way, “ up,” and its correlative “down," although relating exclusively to the earth, and in reality changing in direction each inoment as that turns upon its axis, have become so intimately connected with our notion of space, that we cannot wholly exclude them, even when we endeavor to form the most absolute and unbounded conception of space, which our limited faculties will permit.
It might be supposed that the apparently local character of our bodily sensations, instead of being the result of a direct constitutional provision, is only the natural consequence of an extension of the sentient principle along the innumerable ramifications of the nerves to every part of the entire frame. Such an explanation, however, would not apply to the case of color and sound, which though equally sensations, we uniformly regard as the attributes of bodies situated wholly without and beyond ourselves. The supposition is moreover directly at variance with the teachings of observation and experiment. These show that the brain is the only part of the nervous system in immediate relation to the spirit. The other and remoter parts have their con
nection with it, through this. If a nerve of sensation be cut, it immediately loses its sensibility. So long as the parts remain separate, the paralysis continues; but when at length nature has effected their re-union, the nerve resumes its wonted properties. By a like separation from the great central organ of all the animal functions, the nerves of voluntary motion are equally disqualified for their proper office, and while the isolation continues, have no more power over the muscles to which they go, than so many threads of any foreign substance. Even the spinal marrow, which from its near resemblance to the brain in composition and structure might be supposed to perform a similar office, in ministering to sensation and voluntary motion serves only as a medium of communication between that and the remoter portions of the nervous system. When it is so far disordered at any point as to cause an interruption of the peculiar action that is propagated along it or the peculiar fluid which is transmitted through it, all the nerves that pass off below that point become paralyzed, and the several parts of the body to which they are distributed lose both their sensibility and their power of motion. By a careful and delicate dissection moreover, the nervous filaments, or rather tubes as they appear when exainined by the aid of the microscope, may be traced from the extremities through this organ up to the brain:
As a further proof that the local reference of our bodily sensations is due to a special organic provision, and not to a general diffusion of the sentient principle, it may be remarked that we do not always conceive of the pain attendant on injury and disease, as situated in the affected part. If a nerve going to the hand or the foot be irritated, the annoyance and suffering experienced are not felt at the point of irritation, but in the hand or foot where the nerve terminates. Every one is acquainted with the sensation produced in the little finger and along the inner edge of the forearm, by a blow on the ulnar nerve where it passes over the elbow. In the same way, the pain experienced after an amputation, from the irritated and inflamed state of the large nervous trunks severed in the operation, continues to be referred by the individual to the removed limb, until the painful certainty of its loss continually forced upon him by his other senses has at length broken up the association. So also after the rhinoplastic operation, performed by detaching, bringing down, and twisting over a portion of the skin of the forehead, until the edges of the flap have become united by vascular and nervous connections to the skin of the face, the sensations caused by touching the new organ are still referred to the forehead. It is well known that tumors generally give rise by their pressure upon adjacent nerves to sensations of uneasiness and