Popular Education - BestLightNovel.com
You’re reading novel Popular Education Part 2 online at BestLightNovel.com. Please use the follow button to get notification about the latest chapter next time when you visit BestLightNovel.com. Use F11 button to read novel in full-screen(PC only). Drop by anytime you want to read free – fast – latest novel. It’s great if you could leave a comment, share your opinion about the new chapters, new novel with others on the internet. We’ll do our best to bring you the finest, latest novel everyday. Enjoy
In every department of nature, _waste_ is invariably the result of _action_. In mechanics, we seek to reduce the waste consequent upon action to the lowest possible degree; but to prevent it entirely is beyond the power of man. Every breath of wind that pa.s.ses over the surface of the earth, modifies the bodies with which it comes in contact. The great toe of the bronze statue of Saint Peter at Rome has been reduced, it is said, to less than half its original size by the successive kisses of the faithful.
In _dead_ or _inanimate_ matter, the destructive influence of action is constantly forced upon our attention by every thing pa.s.sing around us, and so much human ingenuity is exercised to counteract its effects that no reflecting person will dispute the universality of its operation. But when we observe shrubs and trees waving in the wind, and animals undergoing violent exertion, year after year, and continuing to increase in size, we may be inclined, on a superficial view, to regard _living_ bodies as const.i.tuting an exception to this rule. On more careful examination, however, it will appear that waste goes on in living bodies not only without intermission, but with a rapidity immeasurably beyond that which occurs in inanimate objects.
In the vegetable world, for instance, every leaf of a tree is incessantly pouring out some of its fluids, and every flower forming its own fruit and seed, speedily to be separated from, and lost to its parent stem; thus causing in a few months an extent of waste many hundred times greater than what occurs in the same lapse of time after the tree is cut down, and all its living operations are at a close.
The same thing holds true in the animal kingdom: so long as life continues, a copious exhalation from the skin, the lungs, the bowels, and the kidneys goes on without a moment's intermission, and not a movement can be performed which does not in some degree increase the circulation, and add to the general waste. In this way, during violent exertion, several ounces of the fluids of the body are sometimes thrown out by perspiration in a very few minutes; whereas, after life is extinguished, all the excretions cease, and waste is limited to that which results from ordinary chemical decomposition.[6]
[6] For the views presented in the preceding paragraph (as also in several that follow) I would acknowledge my indebtedness to Dr. Andrew Combe's treatise on the "Physiology of Digestion." From the "Principles of Physiology," by the same author, I have already quoted. These admirable works will prove an invaluable treasure to persons desirous of becoming acquainted with the laws of health.
So far, then, the law that waste is attendant on action applies to both dead and living bodies; but beyond this point a remarkable difference between them presents itself. In the physical or inanimate world, what is once lost or worn away _is lost forever_; but _living_ bodies, whether vegetable or animal, possess the distinguis.h.i.+ng characteristic of being able to _repair their own waste_ and add to their own substance. The possession of such a power is essential to their existence. But there is a wide difference between them in other respects. In surveying the respective modes of existence of vegetables and of animals, we perceive the fixity of position of the one, and the free locomotive power of the other. The vegetable grows, flourishes, and dies, fixed to the same spot of earth from which it sprang. However much external circ.u.mstances change around it, it must remain and submit to their influence. At all hours and at all seasons, it is at home, and in direct communication with the soil from which its nourishment is extracted. But it is otherwise with animals: these not only enjoy the privilege of locomotion, but are compelled to use it, and often to go a distance in search of food and shelter. The necessity for a constant change of place being imposed on them, a different arrangement became indispensable for their nutrition. The method which the Creator has provided is not less admirable than simple. To enable animals to move about, and at the same time to maintain a connection with their food, they are provided with a stomach. In this receptacle they can store up a supply of materials from which sustenance may be gradually elaborated during a period of time proportioned to their necessities and mode of life. Animals thus _carry with them_ nourishment adequate to their wants; and the small nutritive vessels imbibe their food from the internal surface of the stomach and bowels, where it is stored up, just as the roots or nutritive vessels of vegetables do from the soil in which they grow. The possession of a stomach or receptacle for food is accordingly a distinguis.h.i.+ng characteristic of the animal system.
The sole objects of nutrition being to repair waste and to admit of growth, the Creator has so arranged that within certain limits it is always most vigorous when growth or waste proceeds with the greatest rapidity. Even in vegetables this provision is distinctly observable. It is also strikingly apparent in animals. Whenever growth is proceeding rapidly, or the animal is undergoing much exertion and expenditure of material, an increased quant.i.ty of food is invariably required. On the other hand, where no new substance is forming, and where, from bodily inactivity, little loss is sustained, a comparatively small supply will suffice. In endowing animals with the sense of _appet.i.te_, including the sensation of hunger and thirst, the Creator has effectually provided against any inconvenience which might otherwise exist, and given to them a guide in relation to both the quality and quant.i.ty of food needful for them, and the times of partaking of it, with that beneficence which distinguishes all his works. He has not only provided an effectual safeguard in the sensations of hunger and thirst, but he has attached to their regulated indulgence a degree of pleasure which never fails to insure attention to their demands, and which, in highly-civilized communities, is apt to lead to excessive gratification. Their end is manifestly to proclaim that nourishment is required for the support of the system. When the body is very actively exercised, and a good deal of waste is effected by perspiration and exhalation from the lungs, the appet.i.te becomes keener, and more urgent for immediate gratification; and if it is indulged, we eat with a relish unknown on other occasions, and afterward experience a sensation of internal comfort pervading the frame, as if every individual part of the body were imbued with a feeling of contentment and satisfaction; the very opposite of the restless discomfort and depression which come upon us, and extend over the whole system, when appet.i.te is disappointed. There is, in short, an obvious and active sympathy between the condition and bearing of the stomach, and those of every part of the animal frame; in virtue of which, hunger is felt very keenly when the general system stands in urgent need of repair, and very moderately when no waste has been suffered.
We have seen that _waste_ is every where attendant upon _action_, and that the object of nutrition is to repair waste and admit of growth. We come now to consider the _Process of Digestion_.
All articles used for food necessarily undergo several changes before they are fitted to const.i.tute a part of the body. In the process of digestion, four different changes should be noticed. More might be specified.
1. MASTICATION.--The first step in the preparation of food for imparting nourishment to the system consists in proper mastication, or chewing.
Food should be thoroughly masticated before it is taken into the stomach. This is necessary in order to break it up and reduce it to a sufficient degree of fineness for the efficient action of the gastric juice. Besides, the action of chewing and the presence of nutrient food const.i.tute a healthful stimulus to the salivary glands, situated in the mouth. By this means, also, the food not only becomes well masticated, but has blended with it a proper amount of saliva, upon both of which conditions the healthy action of the stomach depends. We have here another ill.u.s.tration of the beneficence of the Creator, who has kindly so arranged that the very act of mastication gratifies taste, the mouth being the seat of this sensation. But if we disregard these benevolent laws, and introduce unmasticated food into the stomach, the gastric juice can act only upon its surface, and changes of a purely chemical nature frequently commence in food thus swallowed before digestion can take place. Hence frequently arise--and especially in children and persons of delicate const.i.tution--pains, nausea, and acidity, consequent on the continued presence of undigested aliment in the stomach.
2. CHYMIFICATION.--As soon as food has been thoroughly masticated and impregnated with saliva, it is ready for transmission to the stomach.
This interesting part of the process of digestion, called deglut.i.tion or swallowing, is most easily and pleasantly performed, when the alimentary morsel has been well masticated and properly softened, not by drink, which should never be taken at this time, but by saliva. When the food reaches the stomach, it is converted into a soft, pulpy ma.s.s, called _chyme_; and the process by which this change is effected is called _chymification_. This is the second princ.i.p.al step in digestion, and is effected immediately by the action of the _gastric juice_. This powerful solvent is secreted by the gastric glands, which are excited to action by the presence of food in the stomach. In health, the gastric secretion always bears a direct relation to the quant.i.ty of aliment required by the system. If too much food is taken into the stomach, indigestion is sure to follow, for the sufficient reason that the gastric juice is unable to dissolve it. This is true even when food has been well masticated; but it becomes strikingly apparent when a full meal has been hastily swallowed, both mastication and insalivation having been imperfectly performed.
The time usually occupied in the process of chymification, when food has been properly masticated, varies from _three to four hours_. Digestion is sometimes effected in less time, as in the case of rice, and pigs'
feet soused; but it more commonly requires a longer period, as in the case of salt pork and beef, and many other articles of food, both animal and vegetable.
By the alternate contraction and relaxation of the muscular coat of the stomach, which is excited to action by the presence of food, a kind of churning motion is communicated to its contents that greatly promotes digestion; for by this means every portion of food in turn is brought in contact with the gastric juice as it is discharged from the internal surface of the stomach. This motion continues until the contents of the stomach are converted into chyme, and conveyed into the first intestine, where they undergo another important change.
3. CHYLIFICATION.--As fast as chyme is formed, it is expelled by the contractile power of the stomach into the _duodenum_, or first intestine. It there meets with the _bile_ from the liver, and with the pancreatic juice. By the action of these agents, the chyme is converted into two distinct portions: a milky white fluid, called _chyle_, and a thick yellow residue. This process is called _chylification_, or _chyle-making_. The chyle is then taken up by the absorbent vessels, which are extensively ramified over the inner membrane or lining of the bowels. From the white color of the contents of these vessels, they have been named _lacteals_ or _milk-bearers_, from _lac_, which signifies milk. These lacteals ultimately converge into one trunk, called the _thoracic duct_, which terminates in the great vein under the clavicle or collar bone, hence called the _subclavian_ vein, just before that vein reaches the right side of the heart. Here the chyle is poured into the general current of the venous blood, and, mingling with it, is exposed to the action of the air in the lungs during respiration. By this process, both the chyle and the venous blood are converted into red, arterial, or nutritive blood, which is afterward distributed by the heart through the arteries, to supply nourishment and support to every part of the body. The change which takes place in the lungs is called _sanguification_, or _blood-making_. The chyle is not prepared to impart nourishment to the system until this change takes place. _Respiration_, then, is, in reality, _the completion of digestion_. This interesting and vital part of the process of digestion will be considered more fully in the following chapter.
Before pa.s.sing from this part of the subject, a few remarks of a more general nature seem called for. The _nerves of the stomach_ have a direct relation to _undigested_ but _digestible_ substances. When any body that can not be digested is introduced into the stomach, distinct uneasiness is speedily excited, and an effort is soon made to expel it, either upward by the mouth or downward by the bowels. It is in this way, says Dr. Combe, that bile in the stomach excites nausea, and that tartar emetic produces vomiting. The _nerves of the bowels_, on the other hand, are const.i.tuted in relation to _digested_ food; and, consequently, when any thing escapes into them from the stomach in an _undigested_ state, it becomes a source of irritative excitement. This accounts for the cholic pains and bowel-complaints which so commonly attend the pa.s.sage through the intestinal ca.n.a.l of such indigestible substances as fat, husks of fruits, berries, and cherry-stones.
The process of digestion, which commences in the stomach, is completed in the intestines. Physiologists have hence sometimes called the former part of the process, or chymification, by the more simple term _stomach digestion_; and the latter, or chylification, has been termed _intestinal digestion_. The bowels have distinct coats corresponding with those of the stomach. By the alternate contraction and relaxation of the muscular coat, their contents are propelled in a downward direction, somewhat as motion is propagated from one end of a worm to the other. It has hence been called vermicular, or _wormlike motion_.
Some medicines have the power of _inverting_ the order of the muscular contractions. Emetics operate in this manner to produce vomiting. Other medicines, again, excite the _natural_ action to a higher degree, and induce a cathartic action of the bowels. When medicines become necessary to obviate that kind of costiveness which arises from imperfect intestinal contraction, physicians usually administer rhubarb, aloes, and similar laxatives, combined with tonics. But when the muscular coat of the bowels is kept in a healthy condition by a natural mode of life, and is aided by the action of the abdominal muscles, it rarely becomes necessary to administer laxative medicines.
The inner or mucous coat of the stomach and bowels is generally regarded by physiologists as a continuation of the skin. They greatly resemble each other in structure, and they are well known to sympathize with each other. Eruptions of the skin are very generally the result of disorders of the digestive organs. On the other hand, bowel complaints are frequently produced by a chill on the surface. The mucous coat and the skin are both charged with the double function of _excretion_ and _absorption_. By the exercise of the _former_ function, much of the waste matter of the system, requiring to be removed, is thrown into the intestines, and, mingling with the indigestible portion of the food, forms the common excrement; while by the exercise of the _latter_ function the nutritive portion of their contents is taken up, and, as we have seen, pa.s.ses into the general circulation, and contributes either to promote growth or to repair waste.
4. EVACUATION.--This is the fourth and last princ.i.p.al step in the process of digestion. After the chyle is separated from the chyme and pa.s.ses into the circulation, the indigestible and refuse portion of the food, which is incapable of nouris.h.i.+ng the system, pa.s.ses off through the intestinal ca.n.a.l. In its course its bulk is considerably increased by the excretion of waste matter which has served its purposes in the system, and which, mingling with the innutritious and refuse part of the food, is thrown out of the body in the form of excrement. If the contents of the bowels are too long retained, uneasiness is produced.
Hurtful matter, also, which should pa.s.s off by evacuation, is reabsorbed, pa.s.ses again into the general circulation, and is ultimately thrown out of the system either by the lungs or through the pores of the skin.
This part of the process of digestion is _very important_, for it is impossible to enjoy good health while this function is imperfectly performed. To secure full and natural action in the intestinal ca.n.a.l, several princ.i.p.al conditions are necessary. These are, first, well-digested chyme and chyle; second, a due quant.i.ty and quality of secretions from the mucous or lining membrane of the bowels; third, a free and full contractile power of the muscular coat, and the unrestrained action of the abdominal and respiratory muscles; and, finally, a due nervous sensibility to receive impressions and communicate the necessary stimulus. The contractile power of the muscular coat, and the free pa.s.sage of the intestinal contents from the stomach downward, are greatly aided by the constant but gentle agitation which the whole digestive apparatus receives during the act of breathing, and from exercise of every description. By free and deep inhalations of air into the lungs, the diaphragm is depressed and the bowels are pushed down. But when the air is thrown out from the lungs, the diaphragm rises into the chest, and the bowels follow, being pressed upward by the contractile power of the abdominal muscles. During exercise, breathing is deeper and more free, which gives additional pressure to the bowels from above. The abdominal muscular contraction is also, in turn, more vigorous and extensive, and thus the motion is returned from below. Persons that take little or no exercise, or who allow the chest and bowels to be confined by tight clothing, lose this natural stimulus, and frequently become subjects of immense suffering from habits of costiveness. These should be removed if possible, and they generally can be by a proper course of discipline. This should have reference to both diet and exercise. Such articles of food should be used as tend to keep open the bowels. This should be combined with the free exercise of the lungs and the abdominal muscles. In addition to these, there should be a determination to secure a natural evacuation of the bowels at least once a day. This is regarded by physiologists generally as essential to health. Efforts should be continued until the habit is established. Some definite period should be fixed upon for this purpose. Soon after breakfast is, on many accounts, generally preferable.
TIME FOR MEALS.--Before pa.s.sing from the subject of digestion, I will submit a few thoughts in relation to the times for eating. It has already been observed that _three or four hours_ are generally necessary for the digestion of a simple meal. Usually, perhaps, a greater length of time is required. It is also an established doctrine, based upon the results of careful examination and experiment, that _the stomach requires an interval of rest_, after the process of digestion is finished, to enable it to recover its tone before it can again enter upon the vigorous performance of its function. As a general rule, then, _five or six hours should elapse between meals_. If the mode of life is indolent, a greater time is required; if active, less time will suffice.
Where the usages of society will allow the princ.i.p.al meal to be taken near the middle of the day, the following time for meals is approved by physiologists generally: breakfast at 7 o'clock, dinner at half past 12, and tea at 6. Luncheons and late suppers should be avoided; for the former will always be found to interfere with the healthful performance of the function of digestion, and the latter will induce restlessness, unpleasant dreams, and pain in the head. "A late supper," says the author of the Philosophy of Health, "generally occasions deranged and disturbed sleep; there is an effort on the part of the nerves to be quiet, while the burdened stomach makes an effort to call them into action, and between these two contending efforts there is disturbance--a sort of gastric riot--during the whole night. This disturbance has sometimes terminated in a fit of apoplexy and in death."
THE SKIN.--This membranous covering, which is spread over the surface of the body to s.h.i.+eld the parts beneath, serves also as an excreting and secreting organ. By the great supply of blood which it receives, it is admirably fitted for this purpose. The whole animal system, as we have seen, is in a state of transition, decay and renovation constantly succeeding each other. While the stomach and alimentary ca.n.a.l take in new materials, the skin forms one of the princ.i.p.al outlets by which particles that are useless to the system are thrown out of the body.
Every one knows that the skin perspires, and that checked perspiration is a powerful cause of disease and death; but few have any just notion of the extent and influence of this exhalation. When the body is overheated by exercise, a copious sweat breaks out, which, by evaporation, carries off the excess of heat, and produces an agreeable feeling of coolness and refreshment. The sagacity of Franklin led him to the first discovery of the use of perspiration in reducing the heat of the body, and to point out the a.n.a.logy subsisting between this process and that of the evaporation of water from a rough porous surface, so constantly resorted to in the East and West Indies, and in other warm countries, as an efficacious means of reducing the temperature of the air in rooms, and of wine and other drinks, much below that of the surrounding atmosphere. This is the higher and more obvious degree of the function of exhalation. But in the ordinary state of the system, the skin is constantly giving out a large quant.i.ty of waste materials by what is called _insensible perspiration_; a process which is of great importance to the preservation of health, and which is called _insensible_, because the exhalation, being in the form of vapor, and carried off by the surrounding air, is invisible to the eye. But its presence may often be made manifest, even to the sight, by the near approach of a dry cool mirror, on the surface of which it will soon be condensed so as to become visible. It is this which causes so copious deposits upon the windows of a crowded school-room in cold weather. A portion of these exhalations, however, proceed from the lungs.
There is an experiment that may be easily tried, which affords conclusive evidence that the amount of insensible perspiration is much greater than it is ordinarily supposed to be. Take a dry gla.s.s jar, with a neck three or four inches in diameter, and thrust the hand and a part of the fore-arm into it, closing the s.p.a.ce in the neck about the arm with a handkerchief. After the lapse of a few minutes, it will be seen, by drawing the fingers across the inside of the jar, that the insensible perspiration even from the hand is very considerable. Many attempts have been made to estimate accurately the amount of exhaled matter carried off through the skin; but many difficulties stand in the way of obtaining precise results. There is a great difference in different const.i.tutions, and even in the same person at different times, in consequence of which we must be satisfied with an approximation to the truth.
Although the precise amount of perspiration can not be ascertained, it is generally agreed that the cutaneous exhalation is greater than the united excretions of both bowels and kidneys. Great attention has been given to this subject. Sanctorius, a celebrated medical writer, weighed himself, his food, and his excretions, daily, for thirty days. He inferred from his experiments that _five pounds_ of every eight, of both food and drink, taken into the system, pa.s.s out through the skin. All physiologists agree that from twenty to forty ounces pa.s.s off through the skin of an adult in usual health every twenty-four hours. Take the lowest estimate, and we find the skin charged with the removal of _twenty ounces_ of waste matter from the system _every day_. We can thus see ample reason why checked perspiration proves so detrimental to health; for every twenty-four hours during which such a state continues, we must either have this amount of useless and hurtful matter acc.u.mulating in the system, or some of the other organs of excretion must be greatly overtasked, which obviously can not happen without disturbing their regularity and well-being. It is generally known that continued exposure in a cold day produces either a bowel complaint or inflammation of some internal organ. Instead of expressing surprise at this, if people generally understood the structure and uses of their own bodies, they would rather wonder why one or the other of these effects is not _always_ attendant upon so great a violation of the laws of health, _which are the laws of G.o.d_.
The lungs also excrete a large proportion of waste matter from the system. So far, then, their office is similar to that of the kidneys, the liver, and the bowels. In consequence of this alliance with the skin, these parts are more intimately connected with each other, in both healthy and diseased action, than with other organs. Whenever an organ is unusually delicate, it will be more easily affected by any cause of disease than those which are sound. Thus, in one instance, checked perspiration may produce a bowel complaint, and in another, inflammation of the lungs, and so on. Hence the fitness, in prescribing remedies, of adapting them not only to the _disease_ itself, but of taking into the account the _cause_ of the disease. A bowel complaint, for example, may arise either from overeating or from a check to perspiration. The thing to be cured is the same in both cases, but the _means_ of cure ought obviously to be different. In one instance, an emetic or laxative, to carry off the offending cause, would be the most rational and efficacious remedy; in the other, a diaph.o.r.etic should be administered, to open the skin and restore it to a healthy action. Facts like these expose the ignorance and impudence of the quack, who undertakes to cure every form of disease by one remedy.
It has already been remarked that the skin is charged with the double function of _excretion_ and _absorption_. We have a striking ill.u.s.tration of the exercise of the latter function in the vaccination of children and others, to protect them from small-pox. A small quant.i.ty of cow-pox matter is inserted under the external layer of the skin, where it is acted upon, and in a short time taken into the system by the absorbent vessels. In like manner, when the perspiration is brought to the surface of the skin, and confined there, either by injudicious clothing or by want of cleanliness, there is much reason to believe that its residual parts are again absorbed. It is established by observation that concentrated animal effluvia form a very energetic poison. We can, then, see why the absorption of the residual parts of perspiration produces fever, inflammation, and even death itself, according to its quant.i.ty and degree of concentration. This leads me to notice the importance of
BATHING.--The exhalation from the skin being so constant and extensive, and the bad effects of it when confined being so great, it becomes very important that we provide for its removal. This can be most easily and effectually accomplished by frequently bathing the whole body. This is a luxury within the reach of all, but one which is unappreciated by those who have not enjoyed it. An aged gentleman said to me recently, that in early life he "used to go a swimming frequently and enjoyed it much; but," he added, "I have not bathed or washed myself all over _for the last thirty years_!" This, it is believed, is an extreme case. But it is to be feared there are not wanting instances in which persons do not bathe the entire person once a month, or once a year even! When the residual parts of the perspiration are not removed by was.h.i.+ng or bathing, they at last obstruct the pores and irritate the skin. It is apparently for this reason that, in the Eastern and warmer countries, where perspiration is very copious, ablution and bathing have a.s.sumed the rank and importance of _religious observances_. Those who are in the habit of using the flesh-brush daily are at first surprised at the quant.i.ty of white dry scurf which it brings off; and those who take a warm bath for half an hour at long intervals can not have failed to notice the great amount of impurities which it removes, and the grateful feeling of comfort which its use imparts. It is remarked by an eminent physician, that the warm, tepid, cold, or shower bath, as a means of preserving health, ought to be in as common use as a change of apparel, for it is equally a measure of necessary cleanliness. Many, no doubt, neglect this, and enjoy health notwithstanding; but many more suffer from its omission; and even the former would be greatly benefited by employing it. Cleanliness, then, is as essential to health as to decency. Still more, it promotes not only physical health, but contributes largely to strengthen and invigorate the intellectual faculties, and to elevate and purify the affections. It comes, then, to be ranked among the _cardinal virtues_.
To secure the benefits of bathing or ablution, a great amount of apparatus is not necessary. A shower-bath, or plunge-bath, may not be best for all. Every one can procure a wash-bowl and one or two quarts of water, which are all that is necessary. To prevent the reduction of heat in the system by evaporation, and especially in cold weather, it will usually be found best to bathe the body _by sections_. It is generally agreed that the morning is the best time for bathing. Immediately on rising, then, the clothing being removed, let the head, face, and neck be washed as usual, and thoroughly dried by the use of a towel. Proceed to wash the chest and abdomen, which may be dried as before, after which a coa.r.s.e towel or a flesh-brush should be vigorously applied, until the skin is perfectly dry, and there is a pleasant glow upon the surface.
The back and limbs, in turn, should be washed, dried, and excited to a healthy and pleasant glow by friction. This last is of the utmost importance. If not easily secured, salt or vinegar may be added to the water, both of which are excellent stimulants to the skin.[7] When these are used, and care is taken to excite in the surface, by subsequent friction with a coa.r.s.e towel, flesh-brush, or hair glove, the healthful glow of reaction, it will be found to contribute largely to both physical and mental comfort. The beneficial results will be more apparent if, while bathing and rubbing the chest and abdomen, pains are taken to throw back the shoulders, expand the lungs, and enlarge the chest.
[7] It will frequently be found more convenient, and will be well-nigh as serviceable, to wash in soft water as usual, and excite a reaction in the skin in the use of a towel that has been dipped in brine and dried.
By an act of the Legislature of the commonwealth of Ma.s.sachusetts, pa.s.sed in April last, it is required that "physiology and hygiene shall hereafter be taught in the schools of that commonwealth, in all cases in which the school committee shall deem it expedient."
When physiology is not made a study in school, the teacher should not fail to give familiar and instructive lectures on the subject. I know of instances where, by this simple means, the habits of a whole school, composed of several hundred youth of both s.e.xes, have been radically changed; and the practice of daily ablution has ceased to be the luxury of the few, having become the necessity not only of teachers and scholars, but of the families in which they reside. There is the most satisfactory evidence that cleanliness is conducive to health.[8] How important it is, then, that _habits of cleanliness_ be formed at an early age.
[8] The friends of educational reform may well take courage from the increased attention which the subject of physical education is of late receiving from the _pulpit_ and the _press_, those mighty conservators of the public weal. Since the text was prepared for the press, the following remarks and pertinent inquiry have appeared in the Family Favorite for February, 1850. They are quoted from a Discourse by the editor, the Rev. James V. Watson, on the First Sabbath of the New Year:
"The true interpretation of the providence of G.o.d in Asiatic cholera perhaps has never yet fully been given. Is it not one of G.o.d's marked modes of rebuking intemperance, physical uncleanness, and social degradation--evils which result from perverted appet.i.te, wrong forms of government, and a want of Christian benevolence? The reformer, the philanthropist, and the Christian may learn a lesson here."
Dr. Weiss, a distinguished German physician, in his remarks on this subject, says, the best time, undoubtedly, for these ablutions, is the morning. They are to be performed immediately after rising from the bed, when the temperature of the body is raised by the heat of the bed. The sudden change favors in a great measure the reaction which ensues, and excites the skin, rendered more sensitive by the perspiration during the night, to renewed activity. Cold ablutions, he adds, are fitted for all const.i.tutions; they are best adapted for purifying and strengthening the body; for women, weak subjects, children, and old age. The room in which the ablution is performed may be slightly heated for debilitated patients in winter, to prevent colds in consequence of too low a temperature of the apartment; this exception is, however, only admissible for very weakly persons. Generally speaking, ablutions may be performed in a cold room, especially where persons get through the operation quickly, and can immediately afterward take exercise in the open air.
It is the opinion of Dr. Combe that bathing is a safe and valuable preservative of health, in ordinary circ.u.mstances, and an active remedy in disease. Instead of being dangerous by causing liability to cold, it is, he says, when well managed, so much the reverse, that he has used it much and successfully for the express purpose of diminis.h.i.+ng such liability, both in himself and in others in whom the chest is delicate.
In his own instance, in particular, he is conscious of having derived much advantage from its regular employment, especially in the colder months of the year, during which he has found himself most effectually strengthened against the impression of cold by repeating the bath at shorter intervals than usual. I shall conclude my remarks on bathing by presenting a paragraph from this transatlantic author.
If the bath can not be had at all places, soap and water may be obtained every where, and leave no apology for neglecting the skin. If the const.i.tution be delicate, water and vinegar, or water and salt, used daily, form an excellent and safe means of cleansing and gently stimulating the skin. To the invalid they are highly beneficial, when the nature of the indisposition does not render them improper. A rough and rather coa.r.s.e towel is a very useful auxiliary in such ablutions.
Few of those who have steadiness to keep up the action of the skin by the above means, and to avoid strong and exciting causes, will ever suffer from colds, sore throats, or similar complaints; while, as a means of restoring health, they are often incalculably serviceable. If one tenth of the persevering attention and labor bestowed to so much purpose in rubbing down and currying the skins of horses were bestowed by the human race in keeping themselves in good condition, and a little attention were paid to diet and clothing, colds, nervous diseases, and stomach complaints would cease to form so large an item in the catalogue of human miseries. Man studies the nature of other animals, and adapts his conduct to their const.i.tution; himself alone he continues ignorant of and neglects. He considers himself a being of superior order, and not subject to the laws of organization which regulate the functions of the lower animals; but this conclusion is the result of ignorance and pride, and not a just inference from the premises on which it is ostensibly founded.
CLOTHING.--The skin is very materially affected in the healthy performance of its functions by the nature and condition of the clothing. It is a very commonly received opinion that one princ.i.p.al object in clothing is to impart heat to the body. This, however, is an erroneous idea; the utmost that it can do is to _prevent the escape of heat_. All articles of clothing are not alike in this respect. Some conduct the heat from the body readily, and are hence much used in warm weather; as linen, for example. Others, again, have very little tendency to convey heat from the body, and are hence sought in cold weather. Of this nature are furs, and cloths manufactured from wool. I do not intend in this connection to speak of the merits of different kinds of clothing, but to remark simply upon the necessity of changing clothes often, or at least of ventilating them frequently. This remark applies particularly to all articles of clothing worn next to the skin, and to beds. Clothes worn next to the skin during the day should be removed on going to bed, and a fresh sleeping-gown should be put on. The former should be hung up in a situation that will allow the acc.u.mulated perspiration of the day to pa.s.s off by evaporation. By this means they will become sufficiently freshened and ventilated, by morning, to be worn another day, when the night-clothes, in turn, should be ventilated.
Beds also should be thrown open and exposed to fresh air with open doors, or at least windows, several hours before being made. In our best-regulated boarding schools, and literary and benevolent inst.i.tutions of all kinds, particular attention is now paid to this subject. In some instances, lodging rooms are furnished with frames for the express purpose of facilitating the ventilation of the bed-clothes.
Immediately on rising in the morning, the clothes are removed from the beds, and exposed upon these frames to a current of fresh air for several hours, the windows being opened for that purpose.
Notwithstanding care be taken to promote personal cleanliness by daily ablutions, if the ventilation of beds and clothing be neglected, and perspiration be suffered to acc.u.mulate in them, it may be reabsorbed, and, pa.s.sing again into the circulation, produce all the mischief of which I have before spoken.
THE TEETH.--I have already spoken of the relation the teeth sustain to digestion. Their use in the proper mastication of food is essential to the healthy and vigorous performance of this important function. The proper use of a good set of teeth contributes largely to both the physical comfort, and the intellectual and moral well-being of their possessor; but when neglected, they very commonly decay and become useless; nay, more, they are not unfrequently a source of great and almost constant discomfort for years. In order to preserve the teeth, they must be _kept clean_. After every meal, they should be cleaned with a brush and water. A tooth-pick will sometimes be found necessary in the removal of particles of food that are inaccessible to the brush.
Metallic tooth-picks injure the enamel, and should not be used. Those made of ivory, or the common goose-quill, are un.o.bjectionable. The brush should be used, not only after each meal, but the last thing at night and the first thing in the morning. This will prevent the acc.u.mulation of _tartar_, which so commonly incrusts neglected teeth. If suffered to remain, it gradually acc.u.mulates, presses upon the gums, and destroys their health. By this means the roots of the teeth become bare, and thus deprived of their natural stimulus, they prematurely decay. Food or drink either very hot or very cold is exceedingly injurious to the teeth. Sour drops, acidulated drinks, and all articles of food that "set the teeth on edge," are injurious, and should be carefully avoided.
Should it become necessary to take sour drops as a medicine, they should be given through a quill, and every precaution should be taken to prevent their coming in contact with the teeth. Even then the mouth should be well rinsed immediately after they are swallowed.
Disordered digestion is a great source of injury to the teeth both in childhood and in mature age. When digestion is vigorous, there is less deposition of tartar, and the teeth are naturally of a purer white.
Especially is this true when the general health is good, and the diet plain, and contains a full proportion of vegetable matter. This accounts for the fact that many rustics and savages possess teeth that would be envied in town. Tobacco is sometimes used as a _preservative_ of the teeth. It is, indeed, occasionally prescribed as a _curative_ by ignorant physicians, and those who are willing to pander to the diseased appet.i.tes of their patients. But there is the best medical testimony that the use of this _filthy weed_ "_debilitates the vessels of the gums, turns the teeth yellow, and renders the appearance of the mouth disagreeable._" Dr. Rush informs us that he knew a man in Philadelphia who _lost all his teeth_ by smoking. In speaking of the _moral effects_ of this practice, he adds, "Smoking and chewing tobacco, by rendering water and other simple liquors insipid to the taste, dispose very much to the stronger stimulus of ardent spirits; hence the practice of smoking cigars throughout our country has been followed by the use of brandy and water as a common drink." A dentist of extensive and successful practice in the Middle and Western States, after listening to the reading of this article, said to me, he had a patient, a young lady, two of whose front teeth had decayed through, laterally, in consequence of smoking. On removing the caries, he found it impossible to fill her teeth, because the openings continued through them. He thinks, as do many others, that the heat of the smoke is a princ.i.p.al cause of the injury.
Among the conditions upon which the healthy action of the voluntary organs depends is a due degree of _appropriate exercise_. This is a _general law_, and holds with reference to the _teeth_ as well as to any other organ or set of organs. The proper mastication of healthful and nutritious food const.i.tutes the appropriate exercise of the teeth, and is a condition upon which _their health_, and the healthy exercise of the function of _digestion_, alike depend. If from any cause the teeth of one jaw are removed, the corresponding teeth of the other jaw, being thus deprived of that exercise which is essential to their health, are pressed out of the jaw, appear to grow long, become loose in their sockets, and sometimes fall out. Hence the propriety and advantage of inserting _artificial teeth_ where the natural ones fail; an event which rarely happens when they are properly taken care of. I need hardly add that nuts, and other hard substances that break the enamel, are injurious to the teeth, and should be avoided.