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THE HUMAN MIND.
Tue mind of man has in all times ranked among the rent that the ordinary actions and labours of living most important subjects of human knowledge and in- beings, the things that are seen to attract, repel, or in quiry. Besides being a wonderfully-framed and highly, anyway influence them, their outward manifestations complicated piece of work-infinite in faculty and under every variety of circumstances, the innumerable noble in reason, the mirror of the vast universe with works that they are observed to engage in, or leave out-it is the only seat of human feeling and conscious traces of behind them, form an abundant source of the existence, the exclusive dwelling-place of joy or wo. knowledge now under our consideration; in a word,
There are three great distinct sources of knowledge the drama of human life, the transformations effected respecting the human mind, and these are also the on the face of the external world, the history of manavenues open to us for controlling its workings :- kind, and the entire aggregate of civilisation, combine
1. Outward appearances, actions, and works, and the to teach us what the mind of man is. traces and results of these that are permanently en- II. The second source of our knowledge of mind is graved upon the face of external nature. The inner one that has been too much looked upon by metaphyworkings of the mind are displayed to some extent in sicians as the main source-namely, consciousness, or the outward movements of the body, in the features, the immediate feeling of the mind's doings, which is a looks, utterance, gestures, and movements, or in what part of its nature. The works that a man leaves is called the natural language of man, But the acts behind him express a sum-total of desires, purposes, and operations directed upon external things are a still and capacities, rather than the detailed current more decided class of indications of the character of of emotion and thought. In order to reduce the the mind. The nature of the appetites is shown by trains of mental working to their smallest indiviwhat is visibly seized and devoured; the instincts are dual steps or links, we must attend to our own conmade known by the actions that each creature is ob- sciousness. The great results of the human underserred to perform on the material within its reach, as standing may be seen in the published thoughts, disthe capabilities of a machine are understood from the coveries, and transactions of thinking men; but the effects that it can produce; the various passions and ultimate laws that govern its operations cannot easily emotions may be studied through their various stages be traced from these, although, when discovered, they by noticing the object that excites them, the agitation may be confirmed and illustrated by such results. The and expression of the bodily frame, and the mode of structure of the imagination could not be so readily reaction upon the exciting cause. Anger, gratitude, derived from the ‘Paradise Lost' as from the comaffection, reverence, are all seen under external ap- parison of that great example with the consciousness pearances, and by these they may be distinguished that we have of the workings of the faculty in ourand described, and their causes and effects ascertained. selves. Hence we are to regard the impressions left The acquired habits, and the various characteristics by the mind of its own sensations, thoughts, emotions, of memory, reason, intelligence, belief, conscience, are actions, and volitions, and capable of being revived shown in the same outward way. A child is observed and considered like any other impressions, as one of one day attempting to repeat some act that it sees the means of ascertaining the laws and processes and others doing, the next day it has improved in its general structure of this part of our nature. attempts, and in a short time longer it succeeds in III. The last great source of our knowledge of mind the operation; in which we discern the capacities of is the anatomy and physiology of the human frameobserving, imitating, and acquiring new powers that work, or everything that can be ascertained respecting are inherent in human nature. All the processes and the structure of the human systein. A certain number works which are performed upon the material of the of the bodily organs are directly subservient to the world are so many signs or pieces of information as to operations of the mind, and the mechanism of such the powers of the human mind acting through the organs will therefore be in some measure a clue to bodily organs. The faculties of digging, house-build- these operations. The eye, the ear, the voice, the hand, ing, spinning, and of shaping tools to overcome the are all prominently associated with the susceptibilities powers and resistance of the inanimate world, the and activities of the mind; the whole of the movable adaptation of means to ends, and the application of members of the body, including the limbs, trunk, and the experience of the past to the guidance of the features, are employed in the varied play of thought future, can each be read in clear outward characters, and passion. Moreover, a deeper examination of the like the rising of the sun, the course of the seasons, or bodily frame has shown that the brain, and the innuthe flow of rivers to the sea. And in consequence of merable nervous cords and threads issuing from it to the permanence of many of the products of human every part of the body, are most intimately and indislabour, the purposes, capabilities, and employments of pensably allied with the workings and processes of the departed generations may be made apparent to the mind, and must, for that reason, have their conforview. The remains of cities, fortifications, temples, mation and structure adapted to the precise nature of sepulchres, market-places, and highways, are so many those workings and processes. Hence every discovery indications of the character and pursuits of the men relating to the structure of the brain and nervous who built and occupied them; and we never hesitate system, as well as in the organs of sense and motion, in inferring the one from the other. On the faith of is likely to be of importance in showing the manner of such relics we ascribe taste, imagination, genius, gran- working of the mind that they are expressly formed deur of design, and laborious perseverance to one
This class of fruitful discoveries has of late people, a low order of inventive power to another, and years been very extensive, and they promise to be of bervility under a despotic government to a third.' The the highest use in upravelling the complicated scheme creation of the industrial arts, the organisation of of human nature. As one striking example, it has armies, the building up of the institutions of civil been shown by Sir Charles Bell and others that the society, the worship of the supernatural powers, the nerves ramifying from the brain through the body are investigation of nature, the invention of literature and of two distinct sets or kinds, although both are often art, are all expressive of what is in man; and they joined in the same bundles; and that the nerves of hare always been referred to as examples and illustra- one of the kinds are exclusively employed in carrying tions of the wants, desires, capacities, and endowments impressions from the organs of sense and the different of the race. So that from the whole it must be appa- parts of the body inward to the brain, while the nerves No. 71,
of the other set are as exclusively employed in carry- Ition, the commencing stimulus of a third circle, which ing influences outward from the brain to the moving terminates in acting on a new class of muscles. These and other active organs of the system; the ingoing set contract the chest, and force the air through the nose, being commonly termed nerves of sense, the outgoing the impress of which act is the commencement of a nerves of motion. An impression of touch on the repetition of circle second, or of a circle of inspiration fingers is carried to the brain by one nerve, an influ- and suction; and the two processes of inspiration and ence to put the fingers in motion is carried from the expiration thenceforth go on alternately, until they are brain outward by another nerve; and the same division made to cease by the feeling of satiety. They are, in and distinctness of function are observed everywhere fact, a reinforcement of the breathing process, coupled throughout the system. The nervous framework is with the hold of the nipple by the child's mouth, and thus to be regarded as a series of going and returning the partial stoppage of the nose during the suction. conveyances between the brain and the different parts The action is at first purely of the reflex or unconscious of the body; or the mechanical arrangement that has kind; but, at a subsequent stage of growth, it is liable been adopted in connecting the mind with the bodily to come under the notice and control of the mind. organs is of a circular kind, like the course of the 2. The act of Swallowing.–After a morsel of food has blood. There is reason to believe that every impres- | been chewed under the influence of a conscious operasion made upon the senses, or anywhere upon the body, tion, it passes to the back-part of the tongue, and into and transmitted by the ingoing nerves, has a tendency the bag-like cavity of the pharynx; and by contact to excite in the brain an outgoing stimulus to some of with the surface of this cavity, it excites a movement the outgoing nerves, which ends in putting in motion of muscular contraction which forces it down the gulsome active member of the system. Every act of mind let, and it is carried along the tube of the æsophagus requires not merely a nervous centre, such as some to the stomach. The sensation of contact in each place portion of the brain, but a complete circle of brain, of the alimentary canal excites a contraction of that nerves, and bodily organs, the round of which is de- place which forces the food to the next; and by a scribed by the nervous influence at each operation series of reflex actions, it is conveyed through its whole This must be reckoned the first principle of nervous course. 3. The winking of the eyes is another reflex anatomy in its bearing upon the processes of mind, action, quite independent of our consciousness. Many
The collective recorded experience of mankind, de- of the motions of the lower animals are also reflex, and rived from these three leading sources, are the mate are to be distinguished from the instincts belonging to rials bequeathed to us for learning the character and these animals, which run through the mental life or mechanism of the human mind: these materials we consciousness. The motions of insects are in a great have to sift and compare with themselves, and with measure reflex, the rythmical regulation of them being our own independent observations, until we obtain a the only part that is under the cerebral or mental sysrigorous consistency in all our results. Among the in- tem. Decapitated flies execute movements of their direct helps to the study of mind, in addition to these legs, but of an irregular kind, unlike the rythmical and three great direct sources, are to be reckoned the orderly motions that enable them to walk. sciences that treat of the outer world.
In our exposition of the proper phenomena of mind, REFLEX ACTIONS.
we shall adopt the following divisions of the subject:
1. The SENSATIONS, APPETITES, and INSTINCTS, which There are certain actions performed by men and form an allied group, and make up a 'region of mind in animals which are so distinctly seen to arise from an so far complete in itself, outward stimulus reflected back from a centre in the II, The INTELLECT. form of a movement, that they have specially received III, The EMOTIONS, the name of Reflex Actions. This directness of return, IV. The Activities; meaning such as are of a higher however, is not their distinguishing character, but be- order than the Appetites and Instincts treated of in longs to many actions not so named. What really dis- the first division, and which connect themselves with tinguishes this class of movements, is their being per- the Intellect and Emotions. formed unconsciously, or their not passing through what is properly the mental system of the creature. Their effect is the same as some of the mental actions,
SENSATIONS, APPETITES, AND INSTINCTS. but they lie without the boundary of the true mental The region of Mind proper is defined or circumscribed life. Their exposition is, nevertheless, necessary as a by the peculiarity expressed by the term Consciousness, preliminary to the study of the proper mental pheno- which is an ultimate fact that may be described and
The following are some examples of them :- distinguished from other facts of body or mind, but 1. The act of sucking in infants, which may be said to which cannot be resolved into anything else. Its commence before the dawn of mind. The contact of leading property is as follows : the child's lips with the nipple is an impression of It is the unity, the consolidation, or the centrali. touch conveyed inwards by the nerves of the lips to a sation of the operations of mind. Under it all the ganglion in the spine, and causing a returning influence threads of mental ongoings and movements are reduced which contracts the ring of the mouth, so as closely to to one complex thread, whose course is indivisible. embrace the nipple. This completes one nervous circle, The reflex actions may go on apart and simultaneously, and makes one distinct act ; but it is not the only act. but all that are brought within the sphere of consciousThe muscular contraction of the lips must be assumed ness are rendered mutually dependent, and reduced to to yield a second sensation quite different from the act only by turns. The unity of the conscious thread is first, or from the sensation of contact, and capable of clenched by the fact, that a large portion of the muscular setting in operation a second circle. A nerve will have apparatus of the body is subservient to the operations to convey this second or muscular impression to a sepa- of the mind; and as no part can be used in two ways at rate ganglion, whose outgoing threads proceed to as the same instant, it becomes often a matter of necessity different quarter-namely, to a group of muscles in the that these operations should take their turn instead of back and breast, whose contraction swells out the chest, acting simultaneously. There being but one great exactly as is done in the act drawing in the breath; executive apparatus for the consolidated circles of the or we may imagine that the ganglion in question is mind, there can be as it were but one stream of execumade to connect with the nerves that ordinarily sus- tion, or of movements requiring the use of such appatain the act of inspiration. This act of inspiring air, ratus. But the union of many circles in one great in the present instance, causes a suction at the mouth conscious circle has the farther effect of making each on pneumatic principles, the nose being made partially dependent on all the rest ; anything that one is exclose at the same time, and as part of the same reflex cited to do may be arrested if a stimulus of an opposite act. The inspiration or suction yields a third sensa- | tendency happens to have been conveyed to any other
circle. In the sphere of the organized mind, or of con- stimulus awakened by the impressions of external ob. sciousness, there is a free communication between the jects on those surfaces. In general, we may say that separate centres, which permits of harmony or conflict, an act of Sensation supposes, Ist, A certain object, or mutual assistance or mutual resistance. If a certain influence acting upon the body either from without or motion is given to the arms, and if a motion is also within; 2d, A sensitive surface adapted to receive such given to the eyes, and if the two are in harmony, the impressions; 3d, A nerve whose termination ramifies in coincidence is felt within the system, and the one sen- the sensitive surface, and which proceeds to a central sibly ministers to the support of the other ; but if ganglion ; 4th, The ganglion itself, which is separate there be any incompatibility, a conflict arises, and one and special for each class of sensations; 5th, The nerve must succumb: such harmonies or conflicts are among proceeding from the ganglion in the direction of the the class of feelings resulting from the consolidation of parts excited; 6th, The muscles moved by such nerves the mind into one thread of conscious operations. The which are usually attached to the solid parts lodging more highly a creature is organized, the more perfect is the sensitive surface. In regard to the collateral conthis union of all the operations of the system into a nections of the circle of Sensation with other circles, central train of operations, which enables conflicts to there will also exist nervous communications between be suppressed at once, and tends to cause the various the ganglion and other ganglia, whose operation may processes of life to go on in perfect harmony. The sense occasionally modify the natural course of the primary of vivid mental existence depends on this great pecu-circle. Such collateral communications with other liarity of united action in one organized train. The circles, and especially with the general current of fact of consciousness, and the fact of the mutual con- mind, will have to be occasionally alluded to in the Dection and common understanding of all the more exposition of the Senses in detail.** important operations of the system, go together, if they We are commonly said to have five Senses--Sight, are not one and the same fact. In fine, consciousness Hearing, Touch, Taste, and Smell; but this enumerais mental existence. The various circles may be going tion is now generally admitted to be incomplete. In their rounds of operations; but if they impart no feeling, our present exposition we shall recognise seven different the mind is not awake; the circles are disconnected, and classes of Sensations, as follows :reduced to the mere reflex character. In the state of unconsciousness, any one circle is unable to agitate the
Inferior or Animal Sensations. Superior or Intellectual Sensa. whole frame to sympathise with or assist its movements; 2. Sensations of the Alimentary 5. Sensations of Touch;
1. Sensations of Organic Life; and in this case the pains and pleasures caused by it
6. Sensations of Hcaring; are for the time suspended. Such a state as this is ex
3. Sensations of Taste;
7. Sensations of Sight. emplified in sleep.
4. Sensations of Smell. The arrangement we have now described answers to what may be called General Consciousness, as distinct In this list we have not included the Muscular Feelfrom certain kinds of special consciousness, such as ings, although these are a very distinct class, having that named reflex attention to one's self, self-conscious- very much of the character of Sensations ; but our ness, and the like. The difference is the same as be- reason for so doing is, that the muscles form an essentween seeing and looking, or between the general vision tial part of each sense, and fulfil other functions of a of a wide range of objects and the special or concen- peculiar and distinct kind, which would not be extrated observation of some single object.
pressed by simply classing them among the senses. The three groups of Sensations, and Sensational Appe- They are a wholly unique part of the human system, tites and Instincts, make the inferior region of the true and must be described by themselves, and not as a or conscious mind. They occupy a very prominent, not member of any group whatsoever. We shall have to to say the predominant part of the mental life of the allude to the feelings arising from them in the course great mass of the inferior animals, and are a very con- of our description of the different senses, of each of siderable portion of the far more complicated thread of which they form a part. human consciousness. Of the three classes, the Sensa- The tests of a distinct sense are distinctness of extions are the primary phenomena, and form the starting- ternal object, distinctness of organ, and distinctness of point of the other two: an appetite or an instinct must internal feeling or consciousness. in all cases be preceded or accompanied by a sensation. We shall therefore commence with the Sensations.
1. Sensations of Organic Life.
By these we understand the feelings arising from SENSATIONS AND ORGANS OF SENSE,
the operations and processes for sustaining the life and With regard to Sensations in general, it is particu- vigour of the system; such as, the assimilation of nularly of importance that we should keep in view the tritious matter, the removal of waste, the circulation of fact, that a complete nervous circle is always described, the blood, the action of the various secreting and cornmencing with an impression on a sensitive surface, excreting organs and viscera. It is found that the and ending for the most part in a muscular action. process essential to organic life is the formation of The overlooking of this great and fundamental pro- cells, and the building up of all the tissues after perty of the nervous system has rendered nearly every- the proper fashion of each, which implies the other thing that has been said on the subject of Sensation processes of carrying the proper material to each part, radically incomplete. A Sensation, when allowed free and removing what is superfluous and waste. Bones, scope, never fails to go through the entire round al- joints, muscles, nerves, mucus-membrane, skin, celluready detailed, although, from its being subordinated to lar tissue, &c. must be renewed as fast as it is conthe general stream of mind, the latter part of the circle, sumed; and the acts both of consumption and renewal, or the returning stimulus, may be forcibly arrested, according to the manner that they go on, give rise to a or suspended, or turned into another direction ; but set of feelings or conscious impressions agreeable or nevertheless the phenomenon essentially includes the otherwise. From all parts of the body there would whole course of the completed circle. In describing seem to arise a class of nerves for conveying inward Each class of sensations, we must not merely point out some impression of the general well or ill-being of the the sensitive surface and the objects acting upon it, animal system for the time. Such impression makes but also the returning impulse peculiar to the class, part and parcel of the general consciousness, and of the and the muscles or other organs that are concerned in mental existence and happiness or unhappiness of the this responsive movement. În so doing, we shall gra- individual. It may come equally from the whole dually become acquainted with one leading function frame, or more intensely from some parts than from of the muscular apparatus of the body-namely, its being used to complete the circles of the senses, and to * For a further exposition of the anatomical or physiological move to and fro the parts of the body where the sensi- character of the subjects treated in the present sheet, the reader tire surfaces are lodged, in obedience to the ganglionic is referred to the No. entitled Animal Physiology' in Vol. I.
others, in consequence of some peculiar local influ. | carried to the appropriate central ganglion. This gan
In the case of a general impression of one even glion has not been specifically pointed out by anatomists. character, pleasurable or painful, the muscular response The immediate response of the impression is an is scen in the general attitude of the body, which action upou the general attitude and position of the chimes in with the character of the primary stimulus. body, much in the same way as in the response to the In one state the body assumes a serene, placid, repos- organic sensations. An agrecable stomach-feeling leads ing condition, so as to enable the collective sensation us to adopt an easy, resting, relaxed posture, that may of the system to be more intensely felt; in a different permit the digestive action to have its full sweep, and state, the circle is completed by a series of uneasy to be fully felt; whereas imperfect or obstructed digesmovements and forced attitudes, as if to erade the tion leads to an irritable, uneasy movement, to quench feelings of one's own fleshly existence, or to stifle dis- or suppress the disagreeable serisation. agreeable impressions. But unless the consciousness be In the general consciousness the alimentary feelings wholly engrossed by some other circles of operations, are very powerful, and communicate a decided cast to the well or ill-being of the animal system, as a whole, is the temper of the moment. Scarcely any of the other sure to be felt in the mind, and to carry out a par- sensations are so influential on the pleasurable or painticular stimulus, and impose a particular expression ful, cheerful or gloomy, turn of the thoughts and emoupon the muscular attitude of the body. Hence all tions. Some of the most horrible states of the systein the agents that promote or pervert the healthy action are connected with the stomach ---- as, for instance, of the systenı influence the consciousness through this nausea and sea-sickness. So, on the other hand, at source. "Pure air, wholesome nutriment, proper tem- good dinner is one of the most gladsome influences of perature, a congenial electrical state, all affect us human life. Nature has thus secured a high degree through this branch of our sensibility; and all disor- of attention to the proper choice and timing of the ders, diseases, lacerations, wounds, perverted or exces- matters supplied to the alimentary system, sive action of the assimilating, secreting, absorbing, or The Alimentary Sensations are the first steps or pri. circulating vessels or tissues, influence the inind and mary stimulus of one of the most powerful animal the bodily attitude through the same source. When a appetites, and of a very large amount of the general locality is specially affected, there is a muscular move- ains, purposes, and activity of life both in the lower ment imparted to the locality, such as would tend to creatures and in man. increase the pleasurable or diminish the painful action. Thus a painful wound in the foot keeps up a stimulus of the muscles attached to it, in the vain endeavour to This is a peculiar sense attached to the portal of the give it a position such as would ease the suffering; and alimentary canal, to be an additional help in discrimiit is this muscular endeavour that indicates to the nating what is proper to be taken as food, and an addimind the direction or locality of any special action of tional source of enjoyment in connection with the first an unusual kind in any part. We are often very much reception of nutritive material. agonized in disorders of the inward viscera, in being The substances used as food are more completely unable to direct a muscular movement specially to the distinguished by the taste than by the feelings of digespart, from its being out of reach of our muscles, but tion. The tastes of bodies are as widely different as is we nevertheless are urged to keep up a stimulus on their chemical composition. But in order to have a such as are nearest the disordered region.
taste, a substance must be either liquid or soluble in Compared with the bulk and massiveness of the en- the mouth. Taste is one of our principal means of distire body, the feelings of its well or ill-being are faint, criminating one material from another. There are proif we consider how intensely we are affected by such bably many thousands of different tastes in nature. small organs as the ear, the eye, or the nose. It seems The surface of Taste is the tongue and the overhang. intended merely that we should be sufficiently aware ing palate, which yield a glandular secretion to come of our general state of animal existence, to take an bine with the substance tasted; and the result of this interest in the preservation of our health and vitality, combination acts upon the gustatory nerves, and is without being wholly engrossed by caring for it. Its thence conveyed to the gustatory ganglion. sensations enter into the stream of consciousness with
The muscular response completing the round of a & view of requiring the other circles and activities of sensation of Taste, is directed to the muscles of the mind to do what is necessary for the support of life, mouth, jaws, and throat, and tends either to expel or and for the avoidance of injurious agencies; and we to receive more completely the substance tasted, accordare rewarded by their agreeable character, and by the ing to its character. If agreeable, the matter is kept cheerful cast they throw over our general consciousness, and conveyed to the stomach, in order that it may
be when their indications have been wisely attended to in enjoyed to the full. Many substances unsuitable for the provisions made for our healthy subsistence.
the alimentary canal are rejected by the ordeal of
Taste; but not all unsuitable substances, any more 2. Sensations of the Alimentary Canal.
than all substances unsuitable for organic nutrition It would seem that a special set of nerves is devoted are rejected by the alimentary feeling of the stomach. to receiving into the conscious train the states of the
To produce exquisite Tastes is one of the standing stomach and other parts of the alimentary canal, in endeavours of man, and constitutes the special art of addition to the nerves which give the sensations of or cookery, which, however, is apt to invert the order of ganic life. No other internal organ or viscus affects real importance of the three classes of wants-- of the mind so powerfully as the stomach.
Organic Life, Digestion, and Taste. The sensations are produced by the contact of all The sensations of taste are more distinguishable and kinds of food, and at every stage of its passage through clear in the general consciousness than the sensations the canal, in the mouth, pharynx, æsophagus, stomach, of digestion, but they have a far reaker influence upon und bowels. The character of the food in respect of the total temper and enjoyment of the system. materials and of mechanical consistency determines Taste is the foundation of an appetite distinct from the character of the feeling; hence the range of feel the alimentary appetites, although allied with them; ings is as wide as the range of different alimentary but the craving for objects of Taste does not arise within substances, but the distinction between distinct kinds the system in the same periodical and imperious form is not always very marked; the great characteristic as the craving for food to the stomach. being, how far it agrees with, or can be readily reduced by, the digestive action of the stomach.
The surface of contact is the mucous surface of the This sense is situated close by the sense of Taste, canal, which is covered with glands that secrete liquids and often co-operates with it; but properly the sense of to combine with the food. This act of combination or Smell is the guardian placed at the portal of the lungs mixture gives forth an infțuence to the nerves which is to test the purity of the breathed air,
Sensations of Heat.
The objects of Smell furnished by nature are innu- tially mechanical pressure, or compression of the parts. merable. Their essential conditions are to be volatile, This pressure affects the imbedded nervous fibres, and and to have an agency of a chemical or some other stimulates in them the influence that they carry to the kind on the liquid secreted from the lining membrane nervous centre of touch. The pressure may be of few of the nostrils. Solid bodies cannot have a smell unless points or of many; it may be gentle or heavy, and they possess some volatile ingredient.
accompanied more or less with adhesiveness, as in The surface of the sense is a membrane lining the clammy substances: the pattern of the surface or of complicated cavities, cells, and interior convolutions of its pressing-points may be various without end ; and the nose, which membrane is very extensive in conse- lastly, there may be movement or friction in innumerquence of this cavernous and convoluted arrangement. able degrees and modes; from all which we see the It is covered with mucous glands, which yield the liquor sources of the variety of influences, and the consequent that combines with the smelling emanations; the com- variety of possible sensations. bination producing an impression on the nerves, and The ganglion or central seat of Touch has not been these conveying it to the olfactory ganglion situated completely ascertained, but has been conjectured to within the skull above the cavities of the nose. be a certain portion of the base of the brain called by
The returning muscular influence that completes the anatomists the Thalamus Opticus. circle of a sensation of smell, bears upon the breathing The out-going nerves lead to the muscles of the action, and upon the opening or closing of the nose. organ touched, and the usual responsive action is to A pleasant smell stimulates an increased inhalation of grasp the object in contact; or if it be of a repulsive the breath; a repulsive smell inspires a strong expira- kind, to relax the grasp, and withdraw from it. tion to throw out the offensive matter. Animals have The qualities of body made known by Touch are such thus a timely warning of what is good or bad for the as hardness, roughness, solidity; and in combination breathing apparatus.
with the muscular movements that complete the nerSmells, like tastes, are very clear and distinguish- vous circle, it gives us the sensations of extent of surable, and very delicate tests for discriminating material face, size, and shape. Each muscular position assumed substances: they are therefore extremely valuable in an by the touching organs gives a distinct feeling, and a intellectual point of view; but their massiveness or in- series of muscular positions makes up one characteristic fluence on the temper or condition of the general complex feeling. The muscular part of this sense also consciousness is comparatively small; and only a small gives the feelings of force, strength, and resistance, as portion of human labour is employed in furnishing well as of physical contact. such of them as may be agreeable.
The sensations of Touch are the starting-points, and As giving origin to appetite, smells are more power the source of guidance to a large proportion of bodily ful in suggesting tastes and alimentary gratification movements, instructive, habitual, and voluntary, as in than on their own account.
many of the manual and mechanical operations. In the lower animals, smells are the first step in In the current of the general consciousness, these many appetites, instincts, and actions, which they do sensations are of great importance. not inspire in man. The pursuit of prey, and the desire for the opposite sex, are in many instances initiated by sensations of smell.
These are so very distinct and peculiar, that they
have been sometimes considered as an independent 5. Touch.
class: but there are reasons for believing that they are This we rank as the first of the higher or intellectual only a variety of Touch. They are felt by the surface senses: it being not merely a knowledge-giving sense, appropriated to Touch, and conveyed by the touching as all the senses are, but a means of forming the higher nerves; and the chief action of heat on any body is the combinations which are the instrumentality of intellect. mechanical effect of expansion; or its opposite, con
The great difference between the lower and higher traction. None of the ordinary sensations of Touch, senses is
, that the sensations of the higher are distinctly however, give so powerful a feeling or so energetic a recognised as made up of separate parts lying in diffe- stimulus as heat. The response to an agreeable warmth rent directions, and indicating that the object in contact is to keep up the exposure of the part heated. with the surface of sense is spread over space, and has Heat and cold in the internal parts of the body bedistinguishable portions that may be noticed separately, come mixed in their effect with the organic feelings and lead to a separate muscular response. The feeling and processes, on which they have a very powerful inof Taste or Smelì gives no indication of direction or sur- fluence. The formation of new cells, the oxidation of face, or of the external position, or even the external the tissues, the secretions and excretions, are all stimuexistence of its cause: the muscular response can have lated and controlled by temperature, and the sensation respect only to the sensitive surface as a whole, there of temperature comes to be felt through these. On the being no discrimination between one portion and an- whole, in proportion to the influence of heat on the other. But in Touch, each separate point sends in its system, is the effect of the feeling it gives on the geneseparate sensation, which may bring out a separate ral consciousness, and the craving or appetite founded muscular response, and a distinct act of attention from upon it; and likewise the exertions of human life that the mind at large. The higher sensations have there are set agoing on its account. fore form, shape, and distinctness of parts, and clearly The feeling of warmth combines, with the other senindicate extension in space by requiring the muscular sations of Touch, in discriminating the surfaces of organs of response to travel across the objects from one bodies and their qualities. point to another. Hence in them each nervous thread must have an independent ganglionic centre, and an
6. Sensations of Hearing. independent connection with the responding muscles. This sense is more special and local than Touch, but The lower sensations, on the other hand, are, if we agrees with it in being a mechanical sense, as distinmay so speak, shapeless and inarticulate.
guished from the chemical senses of Taste and Smell. The surface of Touch is the skin, which is unequally The action in the case of hearing is a very refined endowed with sensitiveness; being most sensitive at the case of touch, being the pressure of a liquid on an extips of the fingers, and on the lips and tongue; and panded membrane of great delicacy, into which the least so in the hollow of the back. The test of this nerves of hearing ramify. quality is the nearest distance of two distinguishable The ear consists of three cavities: the outer cavity is points. On the hollow of the back, the points of a open to the air and closed within by a tight membrane, compass three inches apart give only one sensation: on or drumhead, which is the outer wall of the second or the tip of the finger, two points distant by a very small middle cavity: in this middle cavity is contained a fraction of an inch are recognised as distinct.
crooked line of connected bones, one end of the line The kind of action on the touching surface is essen. I being lodged in the drum, and the other end on a hole