THE EDUCATION OF THE FIVE SENSES.

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 Institution and Massachusetts 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 associating them with the immaterial soul. In this life the senses constitute 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 God 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 class 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 class of persons Laura Bridgman and Oliver Caswell. Laura has been several years connected with the institution.

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 illustrate 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 principally 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 institution 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 constitute, 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 substituted for spoken language. In communicating with one another, by means of the manual alphabet, they substitute positions of the hand, which they can both make and see, for letters and words, which they can neither pronounce 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, 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 substituted for spoken language.

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 assuredly 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 destitute 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 cumbrous 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 assumed 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 illustrate 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 passing 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 analogically. 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, destitute 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 illustrated 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 illustrate, 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 substitutes for both eyes and ears. I will mention one or two instances which strikingly illustrate the acuteness of Laura’s sense of touch. When I was at the institution 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 space 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. 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 institution 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.”

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 spaces, 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 unobserved. Fear and grief diminish the impressibility of this tissue, while hope and joy increase it. The quantity and quality of the blood also influence sensation. If this vital fluid becomes impure, or its quantity 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 destitute 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 passing their fingers over raised letters, the sense of touch being substituted 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 passing 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 principal agent in tasting, though the lips, the palate, and the internal surface of the cheeks participate in this function, as does the upper part of the oesophagus. The multitude of points called papillae, scattered over the upper surface of the tongue, constitute 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, butter, 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, assist 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 illustrated 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 illustrated in thousands of instances all over our country by persons who were once accustomed to use strong drink, but who have substituted for it sparkling water, a beverage prepared by God 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-passages 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 canal leading from the eyes to the nose, through which a fluid, that also forms tears, is constantly passing when the passage 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 canal 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-passages 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-passages of the nose are furnished with hairy appendages, which are less or more abundant according to the size of these passages. 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.

It is true that man can accustom himself to nearly all kinds of odor, even to those that at first are very disagreeable. He indeed not unfrequently so vitiates the sense of smell as actually to prefer those scents which, to persons who have preserved the integrity of this sense, are regarded as exceedingly offensive, and even filthy. But why, let me ask, did the Creator give us the sense of smell? Was it to be thus perverted? No, indeed: it was, without doubt, that we might enjoy the refreshing fragrance of flowers and herbs, of food and drink; and also that we might distinguish between air that is pure and healthful, and that which is impure and infectious. As most articles of food which are agreeable to the smell are wholesome, and as those which are disagreeable are generally unwholesome, so, also, those states of the atmosphere which are grateful to this sense are salubrious, and those odors which are pleasant are healthful, while air which is ungrateful will generally be found injurious to health, as will also all those odors which are unpleasant to this sense when in a healthful state. He who has had occasion to enter a crowded court-room, lecture-room, church, or assembly-room of whatever kind, which has been occupied for a considerable time without adequate ventilation, can not fail to remember the unwelcome impression made upon his nasal organs when first he inhaled the vitiated atmosphere within, though by degrees he might have become accustomed to it, did he remain, so as ultimately to become well-nigh insensible to its noisome influence. But let such and all others be well assured that, however offensive such a fetid atmosphere may be to the smell, it is equally injurious to the health. And let those who, having returned from a morning walk or healthful exercise in a salubrious atmosphere, have had occasion to revisit the small and unventilated lodging-room in which they spent a restless night without refreshing sleep, perceive, in the sickening smell, a sufficient cause for all their pains and aches, and wonder how they survived such a gross violation of the organic laws.

All of the senses may be improved by education. The sense of smell constitutes no exception to this rule. Let none be discouraged, then; for the more we accustom our lungs and nasal organs to pure air, the more will they require it, and the more readily will they detect the presence of the least impurity.

This sense becomes very acute in deaf persons, and even more so in the case of those that are blind. The reason is obvious; for, as they are led of necessity to rely upon it more than persons who have all the senses, it becomes thereby developed, and is enabled more accurately to judge of the properties of whatever is submitted to its scrutiny. Seeing persons rarely partake of any article of food, and especially of any thing new, without first smelling it, and blind persons never; for this is the only means by which they can judge of its wholesomeness or unwholesomeness without tasting it.

Whatever stupefies the brain, impairs the healthy action of the nerve of smell, or thickens the membrane that lines the nasal cavities, and thus diminishes the sensibility of the nerves ramified upon it, injures this sense. All these effects are produced by the habitual use of snuff, which, when introduced into the nose, diminishes the sensibility of the nerves, and thickens the lining membrane. By its use the air-passages through the nostrils sometimes become completely obstructed. It is on this account that most habitual snuff-takers are compelled to open their mouths in order to breathe freely. It has been well said, that if Nature had intended that the nose should be used as a snuff-hole, she would doubtless have put it on the other end up.

THE SENSE OF HEARING. The external ear, although curiously shaped, is not the most important part of the organ whose function it is to take cognizance of sounds. In the transmission of sound to the brain, the vibrations of the air produced by the sonorous body are collected by the external ear, and conducted through the auditory canal to the drum of the ear, which is so arranged that it may be relaxed or tightened like the head of an ordinary drum. That its motion may be free, the air contained within the drum has free communication with the external air by an open passage, called the Eustachian tube, leading to the back of the mouth. This tube is sometimes obstructed by wax, when a degree of deafness ensues. But when the obstruction is removed in the effort of sneezing or otherwise, a crack or sudden noise is generally experienced, accompanied usually with an immediate return of acute hearing.

The ear-drum performs a two-fold office; for while it aids in the transmission of sound from without to the internal ear, it at the same time modifies the intensity of sound. This softening of the sound is effected by the relaxation of a muscle when sounds are so acute as to be painful; but when listening to low sounds, the drum is rendered tense by the contraction of this muscle, and the sounds become, by this means, more audible. The vibrations made on the drum are transmitted by the tympanum an irregular bony cavity to the internal ear, which is filled with a watery fluid. In this fluid the filaments of the auditory nerve terminate, which receive and transmit the sound to the brain.

The ear has the power of judging of the direction from which sound comes, as is strikingly exemplified in the fact that when horses or mules march in company at night, those in front direct their ears forward, and those in the rear turn them backward, while those in the center turn them laterally or across, the whole troop seeming to be actuated by a feeling to watch the common safety. This is also illustrated by four or six horse teams, and is a fact with which coachmen are familiar. It is further illustrated by the dog, and many other animals. The external ear of man is likewise furnished with muscles; and savages are said to have the power of moving or directing their ears at pleasure, like a horse, to catch sounds as they come from different directions; but few men in civilized life retain this power.

The acuteness of this sense in men and animals, other things being equal, depends upon the size of the ear. In timid animals, as the hare and the rabbit, the ear is very large. They are thus apprized of the approach of an enemy in time to flee to a place of safety.

The ear-trumpet which is a tube wide at one end, where the sound enters, and narrow at the other, where the ear is applied is constructed on this principle, its sides being so curved that, according to the law of reflection, all the sound which enters it is brought to a focus in the narrow end. It thus increases many fold the intensity of a sound which reaches the ear through it, and enables a person who has become deaf to common conversation to mix again with pleasure in society. The concave hand held behind the ear answers in some degree the purpose of an ear-trumpet.

The Ear of Dionysius, in the dungeons of Syracuse, was a notorious instance of a sound-collecting surface. The roof of the prison was so formed as to collect the words, and even whispers, of the unhappy prisoners, and to direct them along a hidden conduit to where the tyrant sat listening.

Acuteness of hearing requires the healthy action of the brain, and particularly of that portion of it from which the auditory nerve proceeds, combined with perfection in the structure and functions of the different parts of the ear. The best method, then, of retaining and improving the hearing, is to observe well the general laws of health, and particularly to avoid every thing that will in the least impair the structure or healthy action of the parts immediately concerned in the exercise of this function. Inflammatory fevers, affections of the brain, and injuries upon the head, are among the more common causes of imperfect hearing. Hence the impropriety of striking children upon the head in correcting them, whether in the family or in the school. The instances are not few in which deafness, and the impairing of the mental faculties, have resulted from that barbarous practice familiarly known as “boxing the ears.” This inhuman practice is likely to result in injury to the drum of the ear, either in thickening this membrane, or in diminishing its vibratory character. Inflammation of the ear-drum, either acute or chronic, is the common cause of its increased thickness. How often this is produced by blows, the reader may judge. Diminution of the vibratory character of the ear-drum may result from an accumulation of wax upon its outer surface. In such cases chronic inflammation of the parts is not unfrequently the result of the injudicious practice of attempting its removal by introducing the heads of pins into the ear.

This wax, it should be known, is designed to subserve an important end; for the tube leading from the external ear, being, like the nose, constantly open, is liable to the entrance of foreign bodies, such as dust, insects, and the like. But, fortunately, it is not left without the means of defense; for on its inside there are numerous fine bristles, which, interlacing each other, interpose a barrier to the entrance of every thing but sound. Moreover, between the roots of these hairs there are numerous little glands, that secrete a nauseous, bitter wax, which, by its offensiveness, either deters insects from entering, or entangles them and prevents their advance in case they do enter. This wax, then, is very serviceable. But its usefulness does not stop here. When the ear becomes dry from a deficiency of it, the hearing becomes imperfect, as also when it is thin and purulent. This wax not unfrequently becomes hard and obstructs the tube, causing less or more deafness. But this form of deafness may be easily cured, even though it has existed for years; for, having softened the accumulations of viscid wax by dropping animal oil into the ear, they may be removed by the injection of warm soap-suds, which is an effectual and safe remedy.

The sense of hearing is perhaps as susceptible of cultivation as any of the senses. The Indian in the forest, who is accustomed to listen to the approach of his enemies or of his prey, acquires such acuteness of hearing as to be able to detect sounds that would be inaudible to persons living amid the din of civilized life. The blind, also, who of necessity are led to rely more upon this sense than seeing persons, excel in the acuteness of their hearing. They recognize their acquaintances by the exercise of this sense as readily as persons usually do by that of sight, an attainment which very few seeing persons make, and yet one that is perhaps within the reach of ninety-nine persons in every hundred. The blind judge with great accuracy the distance of persons in conversation, of carriages in motion, and of all sonorous bodies whose vibrations reach their ears. They even estimate with remarkable correctness the distance and height of buildings by the reflection or interception of sound. It is in consequence of the acuteness of this sense, acquired by careful cultivation, that the blind, as a class, have become so generally and justly distinguished for their pre-eminence in instrumental music. This enables them also to cultivate vocal music with more than ordinary success.

The due cultivation of the sense of hearing will contribute vastly to promote our intellectual and moral well-being. If it be true, as we are told it is by those who have been engaged in teaching both the deaf and the blind, that the absence of hearing is even a more formidable impediment to the communication of knowledge than that of sight, we must infer that all imperfections of the organ of hearing itself, or in the manner of using it, must correspondingly lessen the accuracy of the knowledge we receive through that organ. The meaning of language very often is conveyed not so much by the words themselves as in the tones of voice in which the words are uttered. If, therefore, the hearing be indistinct, or there be no habit formed of careful attention to the inflections of sound, the impressions received from what we hear must often be inaccurate. Our speech, too, will be far less agreeable, and be inefficient, even if it be not positively inarticulate. We owe it to others, no less than to ourselves, then, to cultivate the powers of the voice the common instrument that God has given us for the interchange of thought, sentiment, and feeling, and which, though so common, is the most perfect of all instruments for the transmission of sound. Yet how deplorably is it neglected! how shamefully is it misused! It can be fully developed and made what it is capable of being only through the influence of the ear. If this organ be neglected, the voice must needs be imperfect. And the voices of many persons are through life imperfect and disagreeable, because they were not carefully trained in early life to articulate distinctly, much less to utter musical sounds. The opinion is confidently expressed by those who are best qualified to decide the matter, that nearly all children might be taught to sing, if proper attention were paid early enough to the use they make of their ears and their organs of sound. The careful training of these should be considered an indispensable part of a school-teacher’s as well as of a parent’s duty.

The ear will find appropriate discipline in distinguishing, without aid from the eye, the causes of various sounds, as the opening of a door, the shutting of a knife, the dropping of various coins, the moving of different articles of furniture, etc. It may also find appropriate exercise in determining the direction from which various sounds proceed; in recognizing acquaintances by their natural voices, and in detecting the counterfeit voices of companions; in arranging and classifying the elementary sounds of the language, and in determining all the different musical tones; in judging of the genus and species of birds by their chirping, of the distance and nature of sonorous bodies of various kinds, etc., etc. These are some of the direct means of improving this sense: others will suggest themselves to the thoughtful reader.

THE SENSE OF SIGHT. The sense of sight, which is the most refined and admirable of all the senses, still remains to be considered. The senses generally serve as interpreters between the material universe without and the spirit within. But it is more especially by the sense of sight that we are enabled to hold converse with the external world. Without it we should be deprived of a large portion of the pleasures of life not only, but even of the means of maintaining our existence. It is through the sense of vision that the wisdom, power, and benevolence of the Deity are chiefly manifested to us.

I shall describe the apparatus of vision only so far as is necessary in order to subserve my leading object, which is the preservation and improvement of this sense, and the means of rendering it tributary to intellectual and moral culture. The eye, which is the organ of vision, is an optical instrument of the most perfect construction. It is surrounded by coats, which contain refracting mediums, called humors. There are three coats, called the sclerotic, the choroid, and the retina; and three humors, called the aqueous, the crystalline, and the vitreous.

The sclerotic or outer coat, called also the white of the eye, is an opaque, fibrous membrane. It has almost the firmness of leather, possesses little sensibility, and is rarely exposed to inflammation or other diseases. It invests the eye on every side except the front, and besides maintaining its globular form and preserving its internal and delicate structure, serves for the attachment of those muscles which move this organ. The opening in the fore part of this opaque coat is filled by the transparent cornea, which resembles a watch crystal in shape, and is received into a groove in the front part of the sclerotic coat in the same manner that a watch-glass is received into its case. But for this arrangement light could not gain admission to the eye.

The choroid coat, which constitutes the second investing membrane of the eye, is of a dark brown color upon its outer surface, and of a deep black within. The internal surface of this membrane secretes a dark substance resembling black paint, upon which the retina is spread out, and which is of great importance in the function of vision, as it seems to absorb the rays of light immediately after they have struck upon the sensible surface of the retina.

The retina, which is the third and innermost membrane of the eye, is the expansion of the optic nerve, and constitutes the immediate seat of vision. Such is the arrangement of the humors of the eye, and so perfectly are they adapted to the functions they are called upon to perform, that in the healthy state of this organ, the light entering the pupil is so refracted as to paint upon the retina an exact image of the objects from which it proceeds. The optic nerve, whose expansion forms the retina, receives this image and transmits it to the mind.

Arnott has well remarked, that “a whole printed sheet of a newspaper may be represented on the retina on less surface than that of a finger nail; and yet not only shall every word and letter be separately perceivable, but even any imperfection of a single letter. Or, more wonderful still, when at night an eye is turned up to the blue vault of heaven, there is portrayed on the little concave of the retina the boundless concave of the sky, with every object in its just proportions. There a moon in beautiful miniature may be sailing among her white-edged clouds, and surrounded by a thousand twinkling stars, so that to an animalcule supposed to be within and near the pupil, the retina might appear another starry firmament with all its glory.”

Besides these three coats, and the cornea which constitutes about one fifth of the anterior portion of the outer coat, it is necessary to notice the iris, so called from its variety of color in different persons, and upon which alone the color of the eye depends. The iris is a circular membrane situated just behind the cornea, and is attached to one of the coats at its circumference. In its center is a small round hole, called the pupil; and sometimes spoken of familiarly as the sight of the eye, as no light can enter the eye except through it. The iris possesses the power of dilating and contracting, so as to admit more or less light, as it may be needed. This change in the size of the pupil is effected by two sets of muscular fibers. The first set converge from the circumference of the iris to the circular margin of the pupil, and constitute the radiated muscle. The outer ends of these fibers are attached to the sclerotic coat, which is unyielding; hence, when they contract, the pupil enlarges to receive more light. The other set is composed of circular fibers, which go round in the iris from the border to the pupil, and constitute the orbicular muscle, the contraction of which diminishes the size of the pupil. When too much light enters the eye, the excited and sensitive retina immediately gives warning of the danger, and the nerves, which are plentifully distributed to the iris, stimulate the orbicular muscle to contract, and the radiated one to relax, by which the size of the pupil is lessened. But when the light which enters the pupil is insufficient to transmit a distinct image of objects to the brain, the orbicular muscle relaxes, and the radiated one contracts, so as to enlarge the pupil. The contraction of the pupil is readily seen when a person passes from a darkened room into a bright sunlight, or when a light is first brought into a room in the twilight of evening. Any person may notice this contraction in his own eye by beholding himself in a glass immediately after passing from a dark to a well-lighted room. So, also, when a person looks at an object near the eye, the pupil contracts, but when he looks at an object more remote, it dilates. The muscles of the iris are somewhat under the control of the will; for most persons can contract or dilate the pupil, in some degree, at pleasure. Some persons possess this faculty to a great extent.

The three humors of the eye have been compared to the glasses of a telescope, and the coats to the tube, which keeps them in their places. The aqueous humor is situated in the fore part of the eye, and is divided by the iris into what are called the anterior and posterior chambers of the eye. The crystalline humor, or lens, is situated immediately behind the aqueous humor, a short distance back of the pupil, and is a perfectly transparent double convex lens, closely resembling in shape the common burning glass. This resemblance does not stop here; for this lens, like the burning glass, possesses the property of converging the rays of light which fall upon it, and bringing them to a focus. When this lens becomes so opaque as to obstruct the passage of light, either partially or entirely, a person is said to have a cataract. This can be cured only by a surgical operation. The vitreous humor, situated back of the other two, forms the principal part of the globe of the eye. It differs from the aqueous in one important particular. When that is discharged in extracting the crystalline lens for cataract or otherwise, it will be restored again in a few hours, and the eye will continue to perform its function. But if this be discharged by accident, the eye is irrecoverably lost. This, however, does not often occur; for, as we shall presently see, the eye is admirably fortified.

The eye is a perfect optical instrument, infinitely surpassing all specimens of human skill. This is true, view it in what light we may. It not only possesses the power of so adjusting its parts as to adapt it to the examination of objects at different distances, and in light of different degrees of intensity, but we are enabled to direct it at will to objects above, beneath, or around us.

The various motions of the eye are produced by six little muscles. These are attached at one extremity to the immovable bones of the orbit, while at the other extremity they are inserted into the sclerotic coat, four of them near its junction with the cornea, by broad, thin tendons, which give to the white of the eye its pearly appearance. These muscles are so arranged by the matchless skill of the Architect as to enable the beholder to direct the eye to any object he chooses, and to hold it there for any length of time that is compatible with the laws by which muscular exercise should be regulated. By the slight or intense action of four of these, called the straight muscles, the eye is less or more compressed, and the relative positions of its humors are by this means so nicely adjusted as to enable us to view objects near by or at a distance. The other two are called oblique muscles, one of which, with its long tendon passing through a cartilaginous loop, acts upon the principle of the fixed pulley, and turns the eye in a direction contrary to its own action. When the external muscle becomes too short, the eye turns out; but if the internal muscle is unduly contracted, the eye turns inward, toward the nose. One eye is sometimes turned up or down, but this is of less frequent occurrence.

It would be interesting to notice the protecting organs of the eye, consisting of the orbit, which is a deep bony socket, in which the eye securely rests; of the eye-brows, which are two projecting arches, covered with hair, and so arranged as to prevent the moisture that accumulates upon the forehead, in free perspiration, from flowing into the eye; of the eye-lids, which are two movable curtains for the protection of the eye, and which secrete a fluid that moistens and lubricates it; of the lachrymal gland, with its ducts, which keeps the eye constantly moist, and whose secretions go on while we wake and when we sleep, etc., etc.; but the preceding must suffice.

With this brief description of the apparatus of vision, we proceed to the consideration of the means of preserving and improving this sense, and of rendering it tributary to intellectual and moral culture.

The rule requiring that action should alternate with rest, which has been so often stated, and which applies to all the organs of both body and mind, should be especially observed in relation to the eye. This organ requires exercise, and light is its appropriate stimulus; but injury is the inevitable consequence of keeping it too constantly employed, or too intently fixed for a long time on any object. Whenever the eye is fixed for any length of time upon an object which it distinguishes with difficulty, it experiences a painful sensation, which is a sure indication that it has been overtaxed. The sight is also impaired when the eye is too little used, or when its natural stimulus is shut out, as is strikingly illustrated in the case of persons confined in dungeons. A distinguished oculist has said that many men daily impair or destroy their eyes by immoderate use, and that not a few have done the same by too little use of them.

The exposure of the eyes to sudden transitions from weak to strong light is very injurious. This may be regarded as one of the must prolific causes of weakness of sight. The injury is generally gradual, it is true, but it is none the less fatal on that account. The immediate sensation of pain, when a strong light is brought into a dark room, should be a sufficient warning to avoid such sudden extremes. The iris dilates and contracts, and thus enlarges or diminishes the size of the pupil as the light that fails upon the eye is faint or strong; but this dilation and contraction are not instantaneous. There are numerous instances on record in which total blindness has resulted from a sudden transition from darkness to the brilliancy of day. The habit of looking at a bright light of any kind, and especially of watching flashes of lightning, which is practiced by many, is exceedingly dangerous. The practice which many students and others indulge in, of resting their eyes as the twilight of evening advances, and allowing the pupil to dilate until it is quite dark, and then suddenly introducing a bright light, is a palpable violation of this rule, and one that is sure, sooner or later, sensibly to injure the eyes. The exposure of the eyes suddenly to a strong light upon waking from sleep, and all sudden changes of whatever kind from darkness to intense light, should be carefully avoided by persons who would preserve their sight unimpaired.

The strength of light used should be regulated according to the powers of the eye. This is a general, though a very important rule. Both the amount and the distribution of light should be such as to produce no unpleasant sensations. The eye possesses a certain degree of adaptation to light, according as it is intense or feeble. Some eyes require a stronger light than others, but all eyes are injured by being used in light that is too intense or too feeble. Reading by a strong sunlight, and by moon or star light, may be adduced as illustrations which are alike painful and injurious.

Too little light is well-nigh as injurious as too much, as he can not fail to have noticed who has had occasion to travel a difficult road in a dark night. The injury, in such cases, is two-fold; for while, on the one hand, the radiated muscle of the iris is unduly contracted for a length of time, in order sufficiently to enlarge the pupil to render objects visible, the sensitive retina, on the other hand, is overtaxed to gain a knowledge of them in too feeble light. The pain which the strained eye thus experiences is only an indication and a warning to the individual of the permanent injury he is inflicting upon this delicate organ.

Rooms should be well and evenly lighted. The irregular and flickering light of common lamps and candles is very injurious, and should be avoided in the study, and in all mechanical pursuits where the eye is much taxed. The best oculists concur in the opinion that reflected and concentrated light are highly injurious. Several cases of actual blindness are recorded as having occurred within a few years from exposure to concentrated light, and weakness of sight that has unfitted the individual for usefulness through life has often been thus produced. The rays of the sun are considered as peculiarly injurious when reflected from an opposite building or wall, or even when they pass through a window, and, descending to the floor, are thence reflected to the eyes. What, then, shall we say of the habit of constructing school-rooms in such a manner that perhaps a majority of the scholars are obliged to write and study at desks upon which the direct rays of the sun shine for a considerable portion of the day unbroken unless it be by a passing cloud! And yet thousands of school-houses are situated in such a manner as to create this very necessity all over our country. At a moderate estimate, the eyes of one hundred thousand children are taxed in this manner in the schools of the United States every passing year. A vast amount of discomfort and unhappiness is produced in this way that might easily be avoided, would parents and teachers take the trouble. Any exposure of this kind should be immediately obviated, either by blinds, or by curtains of some soft color. A few newspapers are much better than nothing. The desks and furniture should be of such a color that the eye may repose upon them with agreeable sensations. Nature is clothed with drapery whose color is refreshing to the eye; and it is false taste, as well as false philosophy, which attempts to dazzle in order to please it.

The use of side lights is injurious. The eye will accommodate itself to light of different degrees of intensity within a limited range, but both eyes should be exposed to an equal degree of light. The sympathy between the eyes is so great, that if the pupil of one eye is dilated by being kept in the shade, as must, of course, be the case where the light is on one side, the eye which is exposed can not contract itself sufficiently for protection, and is almost inevitably injured.

When viewing objects, we should avoid, as far as possible, all oblique positions of the eye. By neglecting this rule, an unnatural and permanent contraction of the muscle is liable to be produced, as is illustrated in the numerous instances of strabismus, or cross-eye, which are every where too common.

We should accustom the eye to viewing objects at different distances. The muscles upon which the form of the eye and the size of the pupil depend are subject to the general laws of muscular action. Their strength and flexibility, which are increased by healthful exercise, are impaired by disuse. Hence students who have neglected this rule, and have accustomed themselves for a long time to view objects near by, lose the power of adjusting the eye so as to view things at a distance. As a consequence, they become near-sighted, and put on glasses, when, by a proper use of the eye, their vision might have been preserved unimpaired many long years. I know some students upon whom this habit became so firmly fixed before they were twenty years of age, that they felt compelled to put on glasses, but who, unwilling to contract so pernicious a habit in early life, commenced a course of discipline in accordance with the suggestions here given. By perseverance, their eyes not only recovered their former healthful action, but became so improved that they now possess the sense of vision unimpaired not only, but in a very high state of cultivation.

Persons become near or long sighted as the objects to which they are accustomed to direct the eye are near or remote. This is illustrated in the case of students, watch-makers, and engravers, who are accustomed to examine minute objects near the eye, and, as a consequence, become near-sighted; and of surveyors, hunters, and sailors, who, being accustomed to view objects at a distance, become long-sighted. By a proper discipline of the eye, persons may attain and retain the power of viewing objects near by and at a distance, as is illustrated in the case of those gunsmiths who are accustomed to manufacture guns, and to try them in shooting at a mark at a great distance. The preceding principles being borne in mind in their various applications. I need, perhaps, state but one more rule.

He who would secure clear and distinct vision, must observe all those rules which are necessary to keep the body in health. The sympathy of the eyes with all the other organs of the body is wonderful and intimate. There is no other organ whose strength depends so much on the general vigor of the system. Strict temperance in eating and drinking may be regarded as an indispensable requisite for the preservation of healthy eyes. To this may be attributed the clear heads of the ancient philosophers, who, unlike most students of the present day, exercised their bodies and limbs as well as their minds. Their works are not the production of congested brains, for these were not oppressed with blood belonging to other parts of the body. They studied and thought, and exercised both body and mind in the open air, and thus observed the laws of health. But among the multitudes of close students of the present day, who complain of weakness of the eyes, the misfortune is generally attributable to an almost total neglect of the first principles of health.

While we reproach and loathe the man whose eyes are red and weeping with the effects of intemperate drinking, we cordially pity purblind students, as in some sense martyrs to the cause of learning. Dr. Reynolds, a distinguished American oculist, administers a rebuke to such which we fear is too often merited: “A closer examination of their history presents a very different result. Our sympathy may grow cool if we regard them with a physiologic eye. It is a love of the flesh, more than a love of the spirit, that too often clouds their vision. It is too much food, crowding with unnecessary blood the tender vessels of the retina. It is too little exercise, allowing these accumulated fluids to settle down into fatal congestion. It is positions wholly at variance with the freedom of the circulation, and various other imprudences, which are the results of carelessness or unjustifiable ignorance. ’The day laborer may eat what he will, provided it is wholesome, and his eyes will not suffer. But let the student, who is called upon to devote not only his eyes, but his brain, to severe labor, live upon highly nutritious food, and such as is difficult of digestion, and we shall soon see how his vision will be impaired, through the vehement and persevering determination of blood to the head, which such a course must inevitably occasion.’ So speaks Beer, whose extensive opportunities of observation have perhaps never been exceeded. The daily practice of every observing oculist is filled with coincident experience.”

Among the prevalent habits of students by which the eyes are injured, the same writer mentions the irritation produced by rubbing them on awaking in the morning, a practice which has in some cases occasioned permanent and incurable disease; reading while the body is in a recumbent position; using the eyes too early after the system has been affected with serious disease; exercising them too much in the examination of minute objects; the popular plan of using green spectacles, and the use of tobacco.

Light which is sufficient for distinct vision, and which falls over the shoulder in an oblique direction, from above, upon the book or study table, is generally regarded, and with great propriety, as best suited to the eyes. Some oculists prefer to have the light fall over the left shoulder.

The acuteness of this sense and the extent of its cultivation are very much greater in some individuals and classes of men than in others. This is a fact that has been remarked by observing persons. Its consequences should not be overlooked, for they are neither few nor unimportant. Those persons who have been long accustomed, either by the necessity of their situation, the example of those about them, or the judicious care of parents and teachers, to observe attentively the relations of parts, the symmetry of forms, or the shades of color, have eyes that are perpetually soliciting their minds to notice some beautiful or grand perceptions. Wherever they turn, they espy some new, and, therefore, curious arrangement of the elements of shape, some striking combination of light and shade, or some delicious peculiarity of coloring. The multiplicity and variety of their perceptions must and do increase the number of their thoughts, or give to their thoughts greater compass and definiteness. Such persons are likely to become poets, or painters, or sculptors, or architects. At any rate, they will appreciate and enjoy the productions of others who have devoted themselves to these delightful arts. And will not such persons be most readily awakened to descry and adore the power, the skill, and the beneficence of the Great Architect who reared the stupendous fabric of the universe, who devised the infinite variety of forms which diversify creation, and whose pencil has so profusely decked every work with myriads of mingling dyes, resulting all from a few parent colors? To an unpracticed eye, the beauties and wonders of creation are all lost. The surface of the earth is a blank, or, at best, but a confused and misty page. Such an eye passes over this scene of things, and makes no communication to the mind that will awaken thought, much less enkindle the spirit of devout adoration, and fill the soul with love to Him “whose universal love smiles every where.”

Mr. May speaks no less sensibly than eloquently when he says, “I may be extravagant in my estimation of the importance of the culture of the eye and the ear, but so it is, that while I have been reading the writings of the Hebrew Prophets, and of those other gifted bards who communed so intently with nature and with nature’s God, it has seemed to me impossible that any one could enter fully into all the tenderness, beauty, and sublimity of their language, or receive into his heart all its peculiarity of meaning, unless his own eye had been used to trace the skill of that hand which framed and fashioned every thing that is, and to descry the delicacy of that pencil which has painted all the flowers of the field, nor unless his own ear has learned to perceive the melody and harmony of sounds.”

We can discipline the sight directly, and to a very great extent; and we can have the satisfaction of perceiving the progressive improvement of the faculty. For this purpose, every school should be furnished with appropriate apparatus. A set of measures is indispensable. I will illustrate by an example. For the benefit of the primary department connected with a seminary of learning that was formerly for several years under my supervision, I constructed a set of rules for linear measurement. Their breadth and thickness were uniform, each being an inch wide and half an inch thick. The set consisted of nine rules, whose lengths were as follows: four were each one foot long; one, a foot and a half long; two, two feet; one, two and a half feet; and one, three feet. Every rule had a small hole bored through each end. I had also a number of small pins turned just the right size to fit these holes. I have since submitted to several hundred teachers, in institutes and elsewhere, my mode of combining and using these measures; and from the deep interest which a large number of intelligent parents and teachers in different localities have manifested in the subject, I venture to refer to it in this connection. I first tried the experiment ten years ago, with a class of about twenty children from four to seven years of age. Several of these could not read, and some of them had not learned the alphabet. The children were first led to observe carefully the length of these several rules, until they could determine at sight the length of each. For several of the first lessons some of them would misjudge. They would, for instance, call a two foot rule one and a half or two and a half feet long. In such cases their judgments were immediately corrected by the application of two one foot rules. They were then led to observe with care, tables, desks, etc., and to estimate their length, and were afterward permitted to measure them, and discover the degree of accuracy in their decisions. After obtaining the opinions of the children in relation to the length or height of an object, I would measure it myself in the presence of the class. When the class became a little experienced, we examined the length, breadth, and height of rooms, of houses, and of churches; and then the distance of objects less or more remote, correcting or confirming their estimates by the application of the rule or measure, which gave a permanent interest to the exercise. By exercising the class in this manner, not to exceed half an hour a day, they would, at the end of the first quarter, judge of each other’s height, of the height of persons generally, of the length of various objects, of the size of buildings, and of the dimensions of yards, gardens, and fields, with greater accuracy than the average of adult persons, as was tested by actual measurement in some instances where there was a disagreement in opinion.

By holding these rules in different positions, the children readily became familiar with the meaning and practical application of the terms perpendicular, horizontal, and oblique. They would also tell which term is applicable to the different parts of the stove-pipe; to the different parts of the furniture of the school-room; to the floor, sides of the room, roof, etc.; and to all objects with which they were familiar.

But the reader may inquire, what is the use of the holes and the pins? By pinning two rules together, one resting upon the other, and then turning one of them around, the class will readily gain a correct idea of the use of the term angle; also of the terms acute angle, right angle, and obtuse angle. By pinning three of these rules together at their ends, the children not only see, but can handle the simplest form of geometrical figures. When this figure is defined, they are enabled permanently to possess themselves of the meaning of the word triangle, by the simultaneous exercise of three senses. By combining rules of the same and different lengths, they become familiar with equilateral, isosceles, scalene, right, and obtuse angled triangles. By combining, in this way, such a set of rules as I have described, the child readily becomes familiar with the names and many of the properties of more than half a score of geometrical figures, with less effort on the part of the teacher than would be required to teach the child the names of the same number of letters. These exercises, then, may well precede the learning of the alphabet, or, at least, proceed simultaneously with it. By this means the child’s interest in the school is increased; his senses are cultivated; he is enabled better to fix his attention; he progresses more rapidly and thoroughly in his juvenile studies, and at the same time lays the foundation for future excellence in penmanship and drawing, and other useful arts.

The child may also be taught to discriminate the varieties of green in leaves and other things; of yellow, red, and blue, in flowers and paints; and to distinguish not only the shades of all the colors, but their respective proportions in mixtures of two or more. Many persons, for want of such early culture, have grown to years without the ability of distinguishing between colors, as others have who have neglected the culture of the ear without the ability of distinguishing between tunes.

Drawing, whether of maps, the shape of objects, or of landscapes, is admirably adapted to discipline the sight. Children should be encouraged carefully to survey and accurately to describe the prominent points of a landscape, both in nature and in picture. Let them point out the elevations and depressions; the mowing, the pasture, the wood, and the tillage land; the trees, the houses, and the streams. Listen to their accounts of their plays, walks, and journeys, and of any events of which they have been witnesses. In these and all other exercises of the sight, children should be encouraged to be strictly accurate; and whenever it is practicable, the judgment they pronounce and the descriptions they give should, if erroneous, be corrected by the truth. Children can not fail to be interested in such exercises; and even where they have been careless and inaccurate observers, they will soon become more watchful and exact.

It is by the benign influences of education only that the senses can be improved. And still their culture has been entirely neglected by perhaps the majority of parents and teachers, who in other respects have manifested a commendable degree of interest in this subject. That by judicious culture the senses may be educated to activity and accuracy, and be made to send larger and purer streams of knowledge to the soul, has been unanswerably proved by an accumulation of unquestionable testimony. Most persons, however, allow the senses to remain uneducated, except as they may be cultivated by fortuitous circumstances. Eyes have they, but they see not; ears have they, but they hear not; neither do they understand. It is not impossible, nor perhaps improbable, that he who has these two senses properly cultivated will derive more unalloyed pleasure in spending a brief hour in gazing upon a beautiful landscape, in examining for the same length of time a simple flower, or in listening to the sweet melody of the linnet as it warbles its song of praise, than those who have neglected the cultivation of the senses experience during their whole lives!

This subject commends itself to all who regard their individual happiness, or who desire to render their usefulness as extensive as possible. Upon parents, teachers, and clergymen, who are more immediately concerned in the correct education of the rising generation, its claims are imperative. Let them be met, in connection with other appropriate means now in use and hereafter to be put in requisition, and our schools can not fail to become increasingly attractive; truancy, hence, will be less frequent, and the benign influences resulting from the correct education of the whole man will inspire the benevolent and philanthropic to renewed and increased efforts to secure the right education of all men, a condition upon which the maximum of human happiness depends.