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immediately employed in the conservation of the body, or in instructing or perfecting the higher senses. To the second class we may attribute the senses which more particularly afford ideas, which the faculties of the mind employ in their operations. Feeling, tasting, and smelling, may be referred to the first class; and to the second belong the senses of seeing and hearing. The sense of touch, which imply those senses which depend upon the absolute contact of bodies with the organs, watches over the safety of the body, and instructs the more refined senses: from this sense we acquire a knowledge of situation, magnitude, and distance; and a capability of judging of these relations by the sense of seeing. All these species, therefore, of the sense of touch are employed in the conservation of the body, and in perfecting the judgment. The sense of seeing, though it is employed as an instrument to watch over the preservation of the body, as well as the sense of touch, yet deserves more particular attention, since it affords those ideas of the mind by which her powers are unfolded, and supplies the materials on which she can operate. The eye affords us infinite pleasure, by enabling us to contemplate visible nature: the reason of the superiority of this pleasure to that which a sense of touch affords, appears to arise chiefly from the conjoint influence of two causes. The sense of touch is greatly confined in its exertions, and to a mind conscious of unlimited space, must always be accompanied with an idea of the petty space into which its power is contracted: the sense of seeing, again, can comprehend a space almost unlimited, when compared with that which our other senses are capable of imparting to the mind. The mind, therefore, when employed in the exercise of the sense of seeing, is conscious of a degree of power and exertion vastly superior to that which she enjoys when occupied in the exercise of any of the other senses, and particularly the sense of touch, whose power is most limited. The employment of the sense of touch again, requires a greater degree of bodily exertion: the impressions by which it is made capable of attaining an accurate idea, are of a stronger and grosser nature than those requisite to impart ideas of visible objects to the eye. But it corrects and determines the truth of ideas formed by the sense of sight. Yet, as this sense seenis only to be wanting in doubtful cases, it is sooner exhausted, and the same degree of pleasure is not affixed to it. The pleasure we derive from the exercise of the sense of seeing, is both more intense than that arising from the sense of touch, and can be longer protracted. Indeed, so little fatigue do the organs of seeing suffer from exercise, that they are continually employed throughout the day, without imparting the least uneasiness arising from fatigue. The ideas which the eye affords are vastly more numerous than those imparted to the mind by the sense of touch, since the space which the eye is capable of occupying, is vastly more extensive than that to which the exercise of touch

is confined. We shall not, however, extend these preliminary remarks, but take up the senses seriatim, according to the simple classification we have adopted.

OF THE SENSE OF TOUCH AND FEELING.

The mechanism of touch is remarkably simple; the skin, which is the organ, is continually submitted to the contact of external bodies, consequently this membrane must incessantly develop the impressions. Feeling is effected without the slightest action being observable in the organ, which is the instrument of the function: thus it is impossible to say in what it consists, and we only know that the sense itself is in the mind. By touch we are enabled to appreciate weight, consistence, motion, extent, and particularly the temperature of bodies; in fact, it is by touch alone, that we experience the sensations of heat and cold; but the judgment we form of these two qualities in bodies, is not precisely connected, as might be supposed by the quantity of caloric they either yield or absorb, because we always compare their temperature with that of the atmosphere in which we live, and to which our body is accustomed. Touch, by the hand itself, is an active feeling effected by a spinal organ, constructed in such a manner as to enable it to seize the surfaces of bodies, and adapt itself to their forms. The hand possesses every favourable condition for the accomplishment of this function. The mechanism of touch is the same as that of feeling, but is more perfect, because the contact itself is more complete. Some philosophers have given touch the name of the geometrical sense; Condillac and Buffon allowed it to have a superiority over the other senses; but, as has been shown, it is rather one that assists the intellect in its judgments. It, however, may be improved by practice to an astonishing degree, and is never sufficiently cultivated by the Educator. Children ought frequently to be led to determine blindfold the qualities of bodies by the touch alone; recognizing confirming, or correcting their impressions afterwards, by means of the cther senses. The perfection of this sense may be useful in passing through life, and there are many circumstances on which a delicate touch will convey information, that can be acquired in no other way; all of which show the great importance of its exercise. Infants in particular, should be very early taught to employ the hand in touching bodies presented to their notice; for it is by this, they obtain a knowledge of their nature and properties, and eventually of form and distance. Children, who have a variety of things put into their hands, have been noticed for a more equitable development of mind than others, and their judgment has been more precocious; therefore the parent will be careful not only to let the little one see an object, but to handle it also.

• How remarkably delicate is the sense of touch in the blind.

THE SENSE OF TASTE.

That the sense of taste is more serviceable to nutrition than intelligence, will be easily seen. We are totally unacquainted with the conditions requisite to make integral particles sapid. Authors have, at times, resorted to geometrical forms to account for the variety of savours; it has been said, that a rounded form was productive of a sweet sensation; that a sour one proceeded from an angular form; that a bitter one is from a square one, &c. The different savours of substance are now generally attributed to the chemical nature of their particles. It is impossible to classify savours, because their numbers are almost unlimited, and because they do not produce the same impression upon every individual. Savours, however, may with respect to every individual, be divided into the agreeable, disagreeable, and mixed. Of all our senses, taste is that which, by the simplicity of its mechanism, approaches the nearest to touch. The phenomena of taste is this:-the tongue, which by meeting, or what is more generally the case, by receiving sapid bodies, brings its nervous papillæ in contact with these substances: from that very moment impression takes place, and the perception of this impression is transmitted to the brain, through the medium of the lingual nerve. Now, the education of the sense of taste is of the utmost importance. The use of all kinds of stimuli, applied to the palate, are to be deprecated; not only from their being almost certain to engender the most dangerous habits; but because they are equally certain to produce disease. The intimate connection between the stomach and the brain is well known. The gratification of the palate leads to the overloading of the stomach: when this is distended, or its tone becomes impaired by improper stimulants, the action of the heart and lungs is interfered with, and congestion in the vessels of the brain is the consequence: the intellectual and moral powers become thus affected; peevishness and irritability are manifested; an inaptitude for study is induced; and the young subject, instead of growing up with the full development of the faculties of his mind, becomes convinced, not that he should eat only to live, but that he lives only to eat.

With these truths before him, the Educator, whether parent or teacher, will be anxious to form for his children a simple taste. If the organs of taste become depraved, which they will do by improper stimulants, the next stage is absolute intemperance; and this is followed by disease both of mind and body. The child should never know, from its sensations after dinner, that it has a stomach, and never be convinced from sweetmeats, brandy balls, or sugar candy, that he has a mouth. Simple diet and pure water are the great ingredients to health, longevity, intellectual power, and even moral conduct.

OF THE SENSE OF SMELLING.

As by the tongue we make ourselves acquainted with savours, so by the olfactory membrane of the nose, and its nerve, do we make ourselves acquainted with odours, which are the minute particles of bodies dissolved, or in a state of suspension in the air, after having been volatalized by caloric. Odours may be classified in the same manner as savours-into the pleasant, the disagreeable, the mixed. The mechanism of the sense of smelling is very simple. In order to reveal the whole mystery, it will suffice to bear in mind, that the olfactory apparatus is situated in the course which air most frequently takes to enter the chest, and that this air is the vehicle by which odours are wafted. In the act of respiration, the nose, by reason of its direction, draws up into the superior part of the nasal fossæ, the air which is loaded with odoriferous particles, and by which these particles are deposited upon the papillæ of the olfactory mucous surface; by this contact, smell is immediately developed, and is instantly propagated along the ethmoidal nerve to the brain, and from thence to the mind, which perceives the impression.

Little need be said of the work of education on this sense: its principal province will be rather to blunt its acute sensibilities, and to remedy those antipathies which it unfortunately occasionally contracts. Instances have occurred, in which the smell of even, apparently, very simple bodies, have produced unexpected and powerful effects upon the nervous system-fainting, hysterical paroxysms, and other morbid phenomena: cases also have occurred in which the most violent aversions have been contracted and kept up through the medium of the nose under these circumstances it will be the part of education to diminish the acuteness of the one state, and to conquer the intensity of the other; and these objects are to be accomplished by graduated, but persevering and habitual exposure, and by the aid of the understanding. Many very foolish people pretend to a great acuteness of this sense, and fancy that nothing should come betwixt the wind and their nobility; and like Hotspur's fop, have their pouncet box ever at hand. Others attempt to enliven themselves, and to raise their spirits by stimuli, in the shape of snuff, which is a compound of ammoniac, salt, orrice root, and tobacco. Ladies, who are not quite so vulgar as to use snuff, think to ward off unpleasant sensations by the use of the smelling bottle, and pyroligneous acid and hartshorn are thrown upon the brain by means of the olfactory apparatus, to its permanent and irremediable injury: the disease of nervousness creating itself an appetite by which it feeds on. The Educator should,

therefore, endeavour to impress upon his pupils the ill effects of these kinds of stimuli; and above all things, the abominable habit of devouring smoke-to the ruin of the breath, eyes, nose, mouth, and teeth. Let the parent and teacher early open the

understanding of the child to these abuses of the organs of smelling, and he will do more for them than by any process specifically directed to the organs themselves.

OF THE SENSE OF HEARING.

We have treated of the senses which are principally corporeal; and we pass on to those that are especially intellectual. Of these, the sense of hearing first claims our attention: sound is the sensation felt when the vibrations communicated to a sonorous body strike the ear; all the forces, in fact, which are received by a body, create a vibratory motion in the molecules of that body which are communicated to the layers of air successively, till they reach the ear, where they determine the nature of sound. We cannot precisely specify what are the physical properties required for a body to be sonorous; all we know is, that the sound, generally speaking, is in a proportional ratio with the solidity and the elasticity of the sonorous body. The mechanism of hearing is extremely beautiful; but physiologists are not agreed on the specific uses of its various parts; and it would be useless to enter into the particulars of the mechanism; but of this we are certain, that the sense of hearing is one of the most indispensable to intelligence: a few metaphysicians have placed vocal language and music among its attributes. Without, however, being the source of these faculties it certainly is materially subservient to them. Similar to every other sense, it admits of perfection by practice, and may be exercised either passively or actively; that is to say, by hearing or listening, being like them, under the control of the will.

In the efforts to cultivate this sense, it is desirable to teach children at first simple sounds; and by degrees those which are more complicated, or at least compounded of several simple tones, together with their several relative distances, and the precise spot whence they come. It is extraordinary how little we are able to determine the exact direction in which sounds lie, or whether they are approaching or receding. Who has not been strangely deceived in his estimate of the distance and the direction of a coach, heard along the road in a still night. But an ostler who has, by habit, perfected this sense, will tell you within a few yards its distance, and whether it is approaching or not. In the farther improvement of hearing, it is desirable to teach children to recognise persons and things, by certain appropriate sounds; to become acquainted with the footsteps of individuals, the different cries of animals, and indeed every variety of sonorous vibration; in order to give a greater degree of accuracy and energy to the organic impressions. Children often endeavour to do this themselves, by the game called Hoop, in which they are guided to the hidden individual by sound alone. In effecting these objects, the first thing to be taught, is the faculty of attention, the direction of the organ towards

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