If the eye be obstructed, the ear opens wide its portals, and hears your very emotions in the varying tones of your voice; if the ear be stopped, the quickened eye will almost read the words as they fall from your lips; and if both be close sealed up, the whole body becomes like a sensitive plant--the quickened skin perceives the very vibrations of the air, and you may even write your thoughts upon it, and receive answers from the sentient soul within.--ANNUAL REPORT _of the Trustees of the Perkins Inst.i.tution and Ma.s.sachusetts Asylum for the Blind_, 1841.

He who formed man of the dust of the earth, and breathed into his nostrils the breath of life, has honored his material organs by a.s.sociating them with the immaterial soul. In this life _the senses_ const.i.tute the great conveyances of knowledge to the human mind. It then becomes not only a legitimate object of inquiry, but one which commends itself to every human being, and especially to every parent and teacher, Can these senses be improved by human interference? And if so, how can that improvement be best effected?

The senses are the interpreters between the material universe without and the spirit within. Without the celestial machinery of sensation, man must have ever remained what Adam was before the Almighty breathed into his form of clay the awakening breath of life. The dormant energies of the mind can be aroused, and the soul can be put into mysterious communion with external nature only by the magical power of sensation.

The possession of all the corporeal senses, and their systematic and judicious culture by all proper appliances, are necessary in order to place man in such a relation to the material universe and its great Architect as most fully and successfully to cultivate the varied capabilities of his nature, and best to subserve the purposes of his creation. He who is deprived of the healthful exercise of one or more of his senses, or, possessing them all unimpaired, has neglected their proper culture, is, from the nature of the case, in a proportionate degree cut off from a knowledge of G.o.d as manifested in his works, and from that happiness which is the legitimate fruit of such knowledge.

Much light has been thrown upon this subject within a few years by the judicious labors of that cla.s.s of practical educators who have devoted their lives to the amelioration of the condition of persons deprived of one or more of the senses. It is difficult to conceive the real condition of the minds of persons thus situated, and especially while they remain uneducated. He who is deprived of the sense of sight has the windows of his soul closed, and is effectually shut out from this world of light and beauty. In like manner, he who is deprived of the sense of hearing is excluded from the world of music and of speech. What, then, must be the condition of persons deprived of both of these senses? How desolate and cheerless! Yet some such there are.

While on a visit to the Asylum for the Blind, in Boston, a few months ago, I met two of this unfortunate cla.s.s of persons--Laura Bridgman and Oliver Caswell. Laura has been several years connected with the inst.i.tution.

LAURA BRIDGMAN, _the Deaf, Dumb, and Blind Girl_.--So remarkable is the case of this interesting girl, so full of interest, so replete with instruction, and in every way so admirably adapted to ill.u.s.trate the subject of this chapter, that I proceed to give to my readers a sketch of the method pursued in her instruction, together with the results attendant upon it. My information in relation to her is derived from both personal acquaintance and the reports of her case, though princ.i.p.ally from the latter source.

Laura was born in Hanover, New Hampshire, on the 21st of December, 1829.

She is described as having been a very sprightly and pretty infant.

During the first years of her existence she held her life by the feeblest tenure, being subject to severe fits, which seemed to rack her frame almost beyond the power of endurance. At the age of four years her bodily health seemed restored; but what a situation was hers! The darkness and silence of the tomb were around her. No mother's smile called forth her answering smile. No father's voice taught her to imitate his sounds. To her, brothers and sisters were but forms of matter which resisted her touch, but which hardly differed from the furniture of the house save in warmth and in the power of locomotion, and not even in these respects from the dog and the cat. But the immortal spirit implanted within her could not die, nor could it be maimed or mutilated; and, though most of its avenues of communication with the world were cut off, it began to manifest itself through the others. As soon as she could walk, she began to explore the room, and then the house. She thus soon became familiar with the form, density, weight, and heat of every article she could lay her hands upon. She followed her mother, and felt of her hands and arms, as she was occupied about the house, and her disposition to imitate led her to repeat every thing herself. She even learned to sew a little and to knit.

Her affections, too, began to expand, and seemed to be lavished upon the members of her family with peculiar force. But the means of communication with her were very limited. She could be told to go to a place only by being pushed, or to come to one by a sign of drawing her.

Patting her gently on the head signified approbation, on the back disapprobation. She showed every disposition to learn, and manifestly began to use a natural language of her own. She had a sign to express her idea of each member of the family, as drawing her fingers down each side of her face to allude to the whiskers of one, twirling her hand around in imitation of the motion of a spinning-wheel for another, and so on. But, although Laura received all the aid a kind mother could bestow, she soon began to give proof of the importance of language in the development of human character. By the time she was seven years old the moral effects of her privation began to appear, for there was no way of controlling her will but by the absolute power of another, and at this humanity revolts.

At this time, Dr. Samuel G. Howe, the distinguished and successful director of the asylum, learned of her situation, and hastened to see her. He found her with a well-formed figure, a strongly-marked nervous-sanguine temperament, a large and beautifully shaped head, and the whole system in healthy action. Here seemed a rare opportunity of trying a plan for the education of a deaf and blind person, which the doctor had formed on seeing Julia Brace at Hartford. The parents readily consented to her going to the inst.i.tution in Boston, where Laura was received in October, 1837, just before she had completed her eighth year. For a while she was much bewildered. After waiting about two weeks, and until she became acquainted with her new locality, and somewhat familiar with the inmates, the attempt was made to give her a knowledge of arbitrary signs, by which she could interchange thoughts with others. One of two methods was to be adopted. Either the language of signs, on the basis of the natural language she had already commenced herself, was to be built up, or it remained to teach her the purely arbitrary language in common use. The former would have been easy, but very ineffectual. The latter, although very difficult, if accomplished, would prove vastly superior. It was therefore determined upon.

The _blind_ learn to read by means of raised letters, which they gain a knowledge of by the sense of feeling. _The ends of the fingers_, resting upon the raised letters, thus const.i.tute, in part, _the eyes of the blind_. This, although apparently difficult, becomes comparatively easy when the blind person possesses the _sense of hearing_, and is thus enabled to become acquainted with spoken language. On the contrary, the _deaf_, and consequently _dumb_, are unable to acquire a knowledge of spoken language so as to use it with any degree of success. In their education, hence, the _language of signs_, which can be addressed to the eye, is subst.i.tuted for spoken language. In communicating with one another, by means of the _manual alphabet_, they subst.i.tute positions of the hand, which they can both make and see, for letters and words, which they can neither p.r.o.nounce nor hear.

To be deprived of either sight or hearing was formerly regarded as an almost insuperable obstacle in the way of education. Persons deprived of both these senses have heretofore been considered by high legal authorities,[23] as well as by public opinion, as occupying, of necessity, a state of irresponsible and irrecoverable idiocy. By the education of the remaining senses, however, this formidable and heretofore insuperable barrier has been overleaped, or, rather, the obstacle has been met and overcome. The experiment has been successfully tried, once and again, in our own country. The deaf and blind mute has not only acquired a knowledge of reading and writing, and of the common branches of education, but has been enabled successfully to prosecute the study of natural philosophy, of mental science, and of geometry. The accomplishment of all this has resulted from the successful cultivation of the sense of touch or of feeling. The raised letter of the blind has been used for written language, and the manual language of the mute, taken by the _finger-eyes_ of the blind, has been successfully subst.i.tuted for spoken language.

[23] A man is not an idiot if he hath any glimmering of reason, so that he can tell his parents, his age, or the like matters. But a man who is born deaf, dumb, and blind, is looked upon by the law as in the same state with an idiot, he being supposed incapable of any understanding, as wanting all the senses which furnish the human mind with ideas.--_Blackstone's Commentaries_, vol. i., p. 304.

Laura's mind dwelt in darkness and silence. In order, therefore, to communicate to her a knowledge of the arbitrary language in common use, it was necessary to combine the methods of instructing the blind and the deaf. The first experiments in instructing her were made by taking articles in common use, such as knives, forks, spoons, keys, etc., and pasting upon them labels with their names printed in _raised letters_.

These she felt of very carefully, and soon, of course, distinguished that the crooked lines ~_spoon_~ differed as much from the crooked lines ~_key_~, as the spoon differed from the key in form. Small detached labels, with the same words printed upon them, were then put into her hands, and she soon observed that they were similar to those pasted on the articles. She showed her perception of this similarity by laying the label ~_key_~ upon the key, and the label ~_spoon_~ upon the spoon. When this was done she was encouraged by the natural sign of approbation--patting on the head.

The same process was then repeated with all the articles which she could handle, and she very easily learned to place the proper labels upon them. After a while, instead of labels, the individual letters were given to her, on detached bits of paper. These were at first arranged side by side, so as to spell ~_book_~, ~_key_~, &c. They were then mixed up, and a sign was made for her to arrange them herself, so as to express the words ~_book_~, ~_key_~, etc., and she did so.

The process of instruction, hitherto, had been mechanical, and the success attending it about as great as that in teaching a very knowing dog a variety of tricks. The poor child sat in mute amazement, and patiently imitated every thing her teacher did. Presently the truth began to flash upon her; her intellect began to work; she perceived that here was a way by which she could herself make up a sign of any thing that was in her own mind, and show it to another mind, and at once her countenance lighted up with a human expression! her immortal spirit eagerly seizing upon a new link of union with other spirits! Dr. Howe says he could almost fix upon the moment when this truth dawned upon her mind and spread its light to her countenance. He saw at once that nothing but patient and persevering, but judicious efforts were needed in her instruction, and that these would most a.s.suredly be crowned with success.

It is difficult to form a just conception of the amount of labor bestowed upon Laura thus far. In communicating with her, spoken language could not be used, for she was dest.i.tute of hearing. Neither are signs of any use when addressed to the eyes of the blind. When, therefore, it was said that "a sign was made," we are to understand by it that the action was performed by her teacher, she feeling of his hands, and then imitating the motion. The next step in the process of her instruction was to procure a set of metal types, with the different letters of the alphabet cast upon their ends; also a board, in which were square holes, into which she could set the types so that the letters on the end could alone be felt above the surface. Then, on any article being handed to her whose name she had learned--a pencil or a watch, for instance--she would select the component letters and arrange them on her board, and read them with apparent pleasure.

When she had been exercised in this way for several weeks, and until her knowledge of words had become considerably extensive, the important step was taken of teaching her how to represent the different letters by the position of her fingers, instead of the c.u.mbrous apparatus of the board and types. This she accomplished speedily and easily, for her intellect had begun to work in aid of her teacher, and her progress was rapid.

Six months after Laura had left home her mother went to visit her. The scene of their meeting was full of interest. The mother stood some time gazing with overflowing eyes upon her unfortunate child, who, all unconscious of her presence, was playing about the room. Presently Laura ran against her, and at once began feeling of her hands, examining her dress, and trying to find out if she knew her; but, not succeeding in this, she turned away as from a stranger, and the poor woman could not conceal the pang she felt at finding her beloved child did not know her.

She then gave Laura a string of beads which she used to wear at home.

These were at once recognized by the child, who gave satisfactory indications that she understood they were from home. The mother now tried to caress her; but Laura repelled her, preferring to be with her acquaintances.

Other articles from home were then given to Laura, and she began to look much interested; she examined the stranger much closer, and gave the doctor to understand she knew they came from Hanover; she now even endured her mother's caresses, but would leave her with indifference at the slightest signal. After a while, on the mother taking hold of her again, a vague idea seemed to flit across Laura's mind that this could not be a stranger; she therefore felt of her hands very eagerly, while her countenance a.s.sumed an expression of intense interest; she became very pale, and then suddenly red; hope seemed struggling with doubt and anxiety, and never were contending emotions more strongly painted upon the human face. At this moment of painful uncertainty, the mother drew Laura close to her side, and kissed her fondly, when at once the truth flashed upon the child, and all distrust and anxiety disappeared from her face. With an expression of exceeding joy, Laura nestled to the bosom of her parent, and yielded herself to her fond embraces. After this the beads were all unheeded, and the playthings which were offered to her were utterly disregarded. Her playmates, for whom she but a moment before left the stranger, now vainly strove to pull her from her mother. The meeting and subsequent parting showed alike the affection, the intelligence, and the resolution of the child as well as of her mother.

The following facts are drawn from the report made of her case at the end of the year 1839, after she had been a little more than two years under instruction. Having mastered the manual alphabet of the deaf mutes, and having learned to spell readily the names of every thing within her reach, she was then taught words expressive of positive qualities, as hardness and softness. This was a very difficult process.

She was next taught those expressions of relation to place which she could understand. A ring, for example, was taken and placed _on_ a box; then the words were spelled to her, and she repeated them from imitation. The ring was afterward placed _on_ a hat, desk, etc. In a similar manner she learned the use of _in_, _into_, etc. She would ill.u.s.trate the use of these and other words as follows: She would spell ~_on_~, and then lay one hand _on_ the other; then she would spell ~_into_~, and inclose one hand _within_ the other.

Laura very easily acquired a knowledge and use of active verbs, especially those expressive of _tangible action_, as to walk, to run, to sew, to shake. In acquiring a knowledge of language, she used the words with which she had become acquainted in a general sense, and according to the order of _her sense of ideas_. Thus, in asking some one to give her bread, she would first use the word expressive of the leading idea, and say, _Bread, give, Laura_. If she wanted water, she would say, _Water, drink, Laura_.

Having acquired the use of substantives, adjectives, verbs, prepositions, and conjunctions, it was thought time to make the experiment of trying to teach her to _write_, and to show her she might communicate her ideas to persons not in contact with her. It was amusing to witness the mute amazement with which she submitted to the process; the docility with which she imitated every motion, and the perseverance with which she moved her pencil over and over again in the same track, until she could form the letter. But when at last the idea dawned upon her that by this mysterious process she could make other people understand what she thought, her joy was boundless! Never did a child apply more eagerly and joyfully to any task than she did to this; and in a few months she could make every letter distinctly, and separate words from each other.

At this time Laura actually wrote, unaided, a legible letter to her mother, in which she expressed the idea of her being well, and of her expectation of going home in a few weeks. It was, indeed, a very rude and imperfect letter, couched in the language which a prattling infant would use. Still, it shadowed forth and expressed to her mother the ideas that were pa.s.sing in her own mind. She had attained about the same command of language as common children three years of age. But her power of expression was, of course, by no means equal to her power of conception; for she had no words to express many of the perceptions and sensations which her mind doubtless experienced. In the spring of 1840, when she had been under instruction about two and a half years, returning fatigued from her journey home, she complained of a pain in her side, and on being asked what caused it, she replied as follows: "Laura did go to see mother, ride did make Laura side ache, horse was wrong, did not run softly." Her improvement in the use of language was very rapid, and she soon became, in some respects, quite a critic. When one of the girls had the mumps, Laura learned the name of the disease; soon after she had it herself, but she had the swelling only on one side; and some one saying to her, "You have got the mumps," she replied quickly, "_No, no; I have mump._"

About this time Laura learned the difference between the present and past tense of the verb. And here her simplicity rebukes the clumsy irregularities of our language. She learned _jump, jumped_--_walk, walked_, etc., until she had an idea of the mode of forming the imperfect tense of regular verbs; but when she came to the word _see_, she insisted that it should be _seed_ in the imperfect; and upon going down to dinner, she asked if it was _eat, eated_; but being told it was _eat_, ATE, she seemed to try to express the idea that this transposition of the letters was not only wrong, but ludicrous, for she laughed heartily. She continued this habit of forming words a.n.a.logically. When she had become acquainted with the meaning of the word restless, she seemed to understand that _less_ at the end of a word means without, dest.i.tute of, or wanting, as rest-less, fruit-less; also that _ful_ at the end of a word expresses abundance of what is implied by the primitive, as bliss-ful, play-ful. This is clearly ill.u.s.trated in the following expressions. One day, feeling weak, she said, "I am very strongless." Being told this was not right, she said, "Why, you say restless when I do not sit still." Then she said, "I am very weakful."

My primary object in referring to Laura has been to ill.u.s.trate, in a striking manner, the practicability of the education of the senses to an extent not heretofore generally known. To such an extent has the sense of touch been cultivated in her, that her fingers serve as very good subst.i.tutes for both eyes and ears. I will mention one or two instances which strikingly ill.u.s.trate the acuteness of Laura's sense of touch. When I was at the inst.i.tution a few months ago, she was told a person was present whom she had never met, and who wished an introduction to her. She reached her hand, expecting to meet a _stranger_. By mistake (for her teachers design never to allow her to be deceived), she took the hand of another gentleman, whom she recognized immediately, though she had never met him but twice before. She recognizes her acquaintances in an instant by touching their hands or their dress, and there are probably hundreds of individuals who, if they were to stand in a row, and hold out each a hand to her, would be recognized by that alone. The memory of these sensations is very vivid, and she will readily recognize a person whom she has once thus touched.

Many cases of this kind have been noticed; such as a person shaking hands with her, and making a peculiar pressure with one finger, and repeating this on his second visit, after a lapse of many months, being instantly known by her. She has been known to recognize persons with whom she had thus simply shaken hands but once, after a lapse of six months. But this is hardly more wonderful than that one should be able to recall impressions made upon the mind through the organ of sight, as when we recognize a person of whom we have had but one glimpse a year before; but it shows the exhaustless capacity of those organs which the Creator has bestowed, as it were, in reserve against accidents, and which we too commonly allow to lie unused and unvalued.

OLIVER CASWELL.--Had I not devoted so much s.p.a.ce to this subject already, it would be interesting to consider the case of Oliver, who, like Laura, is deaf, dumb, and blind. His experience is full of interest, though less striking than that already presented. His progress in learning language, and in acquiring intellectual knowledge, is comparatively slow, because he has not that fineness of fiber and that activity of temperament which enable Laura to struggle so successfully against the immense disadvantages under which they both labor. Oliver is a boy of rather unfavorable organization; he had been deaf and blind from infancy; he received no instruction until he was twelve years old, and consequently lost the most precious years for learning; he has nevertheless been taught to express his thoughts both by the finger language and by writing; he has also become acquainted with the rudiments of the common branches of education, and is intelligent and morally responsible. His case proves, therefore, very clearly, that the success of the attempt made to instruct Laura Bridgman was not owing solely to her uncommon capacity.

Oliver's natural ability is small, and his acquired knowledge very limited; but his sense of right and wrong, his obedience to moral obligations, and his attachment to friends, are very remarkable.[24] He never willfully violates the rights or injures the feelings of others, and seldom shows any signs of temper when his own seem to be invaded. He even bears the teasing of little boys with gentleness and patience. He is very tractable, and always obeys respectfully the requests of his teacher. This shows the effect which kind and gentle treatment has had upon his character, for when he first went to the inst.i.tution in Boston he was sometimes very willful, and showed occasional outbursts of temper which were fearfully violent. "It seems hardly possible," says Dr. Howe, "that the gentle and affectionate youth, who loves all the household and is beloved by all in return, should be the same who a few years ago scratched and bit, like a young savage, those who attempted to control him."

[24] I have omitted much in the case of Laura that I should have retained but for want of room. The moral qualities of her nature have developed themselves most clearly. She is honest to a proverb, having never been known to take any thing belonging to another. That she is a Christian there can be no doubt. It is said in the report of her case for 1846, that "on the last occasion of her manifesting any impatience, she said to Miss Wight, her teacher, '_I felt cross, but in a minute I thought of Christ, how good and gentle he was, and my bad feelings went away._'"

We regard it as a fact fully established that the sense of touch may be cultivated to a much greater extent than most persons are aware of. The same remark will apply to the cultivation of all the senses. We shall consider them separately.

THE SENSE OF TOUCH.--The remarks already made apply chiefly to this sense. The nerves that supply it proceed from the anterior half of the spinal cord. This sense is most delicate where there are the greatest number of nervous filaments, and those of the largest size. The hands, and especially the fingers, have a most delicate and nice sense of touch, though the sense is extended over the whole body, in every part of which it is less or more acute. In this respect, then, this sense is unlike the others, which are confined to small s.p.a.ces, as we shall see when we come to consider them. The action of the sensitive nerves depends upon the state of the brain, and the condition of the system generally. In sound and perfect sleep, when the brain is inactive, ordinary impressions made upon the skin are un.o.bserved. Fear and grief diminish the impressibility of this tissue, while hope and joy increase it. The quant.i.ty and quality of the blood also influence sensation. If this vital fluid becomes impure, or its quant.i.ty is diminished, the sensibility of the skin will be impaired thereby. Whatever affects the general health affects the healthy action of this sense. It is also much affected by sudden changes in temperature. If the skin is wounded while under the influence of cold, the pain will be slight. By carrying this chilling influence too far, the surface becomes entirely dest.i.tute of sensation. This is produced by the contraction of the blood-vessels upon the surface. On the contrary, when the chilled extremities are suddenly exposed to heat, the rapid enlargement of the contracted blood-vessels excites the nerves unduly, which causes the pain experienced on such occasions.

The sensibility of the nerves depends much upon the habits of persons.

Suppose two boys go out to play when the thermometer stands at the freezing point, and that one of them has been accustomed to exercise in the open air, and to practice daily ablution, while the other one has been confined most of the time to a warm room, and has been accustomed to wash only his hands and face. The skin of the former, other things being equal, will be active and healthy, while that of the latter will be enfeebled and diseased. The organs of touch diffused over the body at the surface will be very differently affected in these two boys, and the perceptions of their minds will be alike dissimilar. One will be roused to action, and will feel just right for some animating game. Both body and mind will be elastic and joyous. He will bound like the roe, make the welkin ring with his merry shout, and return to the bosom of his family with a gladdened heart, ready to impart and receive pleasure, while the other boy will be too keenly affected by the contact of the air, and think it too cold to stay out of doors. He will thrust his hands into his pockets, and curl himself up like one decrepit with age.

His teeth will chatter and his whole frame tremble. Of course, very different reflections will be awakened in his mind. He will hurry back to the fireside, thinking winter a very dismal season, and will be apt to fret himself and all about him, because of the confinement from which he has not the resolution to break out.

The sensibility of the cutaneous nerves in these two cases depends upon the habits of the persons. If the latter would practice frequent ablutions, and excite a healthy action in the skin by friction and exercise, and conform to other laws of health, he would experience all that gladness of heart, and elasticity of body and mind, which the other is supposed to enjoy. Hence the advantages resulting from a strict conformity to the laws of health in this particular as well as in others that are generally regarded as more important.

The general law that the exercise of a faculty increases its power is applicable to the senses. We have referred to the blind, who read as rapidly as seeing persons by pa.s.sing their fingers over raised letters, the sense of touch being subst.i.tuted by them for that of vision. Nor is the education of this sense useful to the blind merely. It may frequently be appealed to with great advantage by all who have cultivated it. The miller, for example, can judge more accurately of the quality of flour and meal, by pa.s.sing some between his fingers than by the exercise of vision. The cloth-dresser, also, by the aid of this sense, not only marks the nicest shades of texture in examining cloths of different qualities, but in many instances learns to distinguish _colors_ by the sense of touch with perhaps greater accuracy than is common with seeing persons.

THE SENSE OF TASTE.--The sense of taste bears the greatest resemblance to the sense of feeling. The upper surface of the tongue is the princ.i.p.al agent in tasting, though the lips, the palate, and the internal surface of the cheeks partic.i.p.ate in this function, as does the upper part of the oesophagus. The mult.i.tude of points called papillae, scattered over the upper surface of the tongue, const.i.tute the more immediate seat of this sense. It is in these sensitive papillae that the ramifications of the gustatory or tasting nerves terminate. When fluids are taken into the mouth, and especially those whose taste is pungent, these papillae dilate and erect themselves, and the particular sensation produced is transmitted to the brain through the medium of the minute filaments of the gustatory nerves.

In order fully to gratify the taste in eating dry, solid food, it is necessary that the food be first reduced to a liquid state, or, at least, that it be thoroughly moistened. Nature has made full provision for this in furnishing the mouth with salivary glands, whose secretions are most abundant when engaged in masticating dry, hard substances.

These quickened secretions contribute to gratify the taste and increase the pleasure of eating, and, at the same time, materially aid in the important processes of mastication and digestion. Nature, also, with her accustomed bounty, has furnished man with a great variety of articles for food. By this means the various tastes of different persons may be gratified, although, in many instances, those articles of food which are most agreeable to some persons are extremely disagreeable to others.

Many persons can not eat the most nourishing food, as fruits, b.u.t.ter, etc., because to them the taste of these articles is disagreeable. But this is very easily accounted for, as in the mouth the food mixes with various fluids that differ in different persons, and in the same person at different times. These fluids, and particularly the saliva, a.s.sist in the formation and change of taste. This accounts not only for the different tastes of different persons, but also for the varying taste of the same persons, and for that fickleness of taste which is so common in sickness, when the fluids of the mouth, in a disordered and deranged state, mix with the food, and produce the disagreeable taste so often complained of at such times, and which, moreover, occasionally create a permanent dislike for food that was previously much relished.

This sense was given to men and animals to guide them in the selection of their food, and to enable them to guard against the use of articles that would be injurious if introduced into the stomach. In the inferior animals, the sense of taste still answers the original design of its bestowment; but in man, it has been abused and perverted by the use of artificial stimulants, which have created an acquired taste that, in most persons, is very detrimental to health. This sense is so modified by habit, that, not unfrequently, articles which were at first exceedingly offensive, become, at length, highly agreeable. It is in this manner that many persons, whose sense of taste has been impaired or perverted, have formed the disgusting and ruinous habits of smoking and chewing tobacco, and of using stimulating and intoxicating drinks. But these pernicious habits, and all similar indulgences, lessen the sensibility of the gustatory nerve, and ultimately destroy the natural relish for healthful food and drink. By this means, also, the digestive powers become disordered, and the general health is materially impaired.

All persons, then, should seek to preserve the natural integrity of this sense, and to restore it immediately to healthy action when at all depraved, for upon this depends much of health and longevity, of happiness and usefulness.

This sense may be rendered very acute by cultivation, as is ill.u.s.trated by persons who are accustomed to taste medicines, liquors, teas, etc. It ought, however, to be chiefly exercised in partaking of those simple articles of food and drink which are most conducive to health. In its natural state it prefers these, and if depraved it will soon recover a healthy tone, if not continually tempted by stimulating substances. This is beautifully ill.u.s.trated in thousands of instances all over our country by persons who were once accustomed to use strong drink, but who have subst.i.tuted for it sparkling water, a beverage prepared by G.o.d himself to nourish and invigorate his creatures, and beautify his footstool.

THE SENSE OF SMELL.--The sense of taste has received a faithful companion in that of smell. The beneficent Creator, with that wisdom which characterizes all his works, has very wisely placed the organ of this sense just above the mouth, in order that the scent of many things that are hurtful may warn us from partaking of them before they reach the mouth. The air-pa.s.sages of the nose, in which this sense is located, are lined with a thin skin, called the mucous membrane, which is continuous with the lining membrane of the parts of the throat and of the external skin. Upon this membrane the olfactory nerve ramifies. The odoriferous particles of matter that float in the air come in contact with these fine and sensitive nerves as the air rushes through the nostrils, and the impression is conveyed to the brain by the olfactory nerve. The mucous membrane, upon which this ramifies, is of considerable extent in man. In the lower animals it is less or more extensive, according to the degree of acuteness of this sense. This membrane is full of little glands that are continually giving off thick mucus, and especially when the membrane is inflamed. There is a small ca.n.a.l leading from the eyes to the nose, through which a fluid, that also forms tears, is constantly pa.s.sing when the pa.s.sage is clear. It is the office of this fluid to moisten and thin the mucus of the nose. When this mucous is too abundant, as in some stages of a cold, and especially if it becomes dry from the closing of the ca.n.a.l leading from the eyes, or from any other cause, as fever, the sense of smell will be greatly impaired, if not entirely suspended. It is, indeed, not unfrequently permanently injured in this way, and sometimes is irrecoverably lost.

The sensation of smell, it should be borne in mind, is produced by a kind of odoriferous vapor, very fine and invisible, that flies off from nearly all bodies. The air which contains this vapor is drawn into the nose, and is in this way brought into contact with the very delicate nerves of smell that ramify the membrane which lines the air-pa.s.sages of this organ. It is only when the exceedingly small particles of which the odor of various bodies is composed come in contact with the minute ramifications of the olfactory nerve that this sensation is produced. In order to protect these sensitive nerves, as well as to prevent the introduction into the lungs of injurious substances, the air-pa.s.sages of the nose are furnished with hairy appendages, which are less or more abundant according to the size of these pa.s.sages. These intercept any foreign substances that enter the nose, and thus irritate the mucous membrane, and cause a quick and powerful contraction of the diaphragm, by which the offending matter is immediately expelled. This phenomenon, which is called sneezing, depends upon a connection of the olfactory with the respiratory nerves.

This sense not only comes in to the aid of taste in enabling man and the lower animals to select proper food, and avoid that which is injurious, but it also gives us positive and varied pleasure by the inhalation of agreeable odors, while, at the same time, it enables us to avoid an infectious atmosphere, and all objects whose odors are offensive and hurtful.