PHYSICAL EDUCATION. THE LAWS OF HEALTH.
If man is ever to be elevated to the highest and happiest condition which his nature will permit, it must be, in no small degree, by the improvement—I might say, the redemption—of his physical powers. But knowledge on any subject must precede improvement.—Alcott.
Physical and moral health are as nearly related as the body and the soul.—Hufeland's Art of Prolonging Life.
If the reader is persuaded that the views presented in the last chapter on the importance of physical education are truthful—and they are concurred in by physiologists generally—he will naturally desire to become acquainted with the laws of health, that, by yielding obedience to them, he may improve his physical condition, and most successfully promote his intellectual and moral well-being. I might, then, here refer to some of the many excellent treatises on this subject; but I shall probably better accomplish the object for which this work has been undertaken by presenting, within as narrow limits as practicable, a summary of these laws.
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 passes 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 passing 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 constituting 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]
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 distinguishing 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 circumstances 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 distinguishing 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 quantity 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 appetite, 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 quantity 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 appetite 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 appetite 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 constitute 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 constitute 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 illustration 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 constitution—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 deglutition 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 mass, called chyme; and the process by which this change is effected is called chymification. This is the second principal 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 quantity 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 passing 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 constituted 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 passage through the intestinal canal 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, passes into the general circulation, and contributes either to promote growth or to repair waste.
4. Evacuation.—This is the fourth and last principal step in the process of digestion. After the chyle is separated from the chyme and passes into the circulation, the indigestible and refuse portion of the food, which is incapable of nourishing the system, passes off through the intestinal canal. 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 pass off by evacuation, is reabsorbed, passes 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 canal, several principal conditions are necessary. These are, first, well-digested chyme and chyle; second, a due quantity 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 passage 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 passing 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 principal 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 shield 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 canal take in new materials, the skin forms one of the principal 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 analogy 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 quantity 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 glass 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 space 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 constitutions, 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, pass out through the skin. All physiologists agree that from twenty to forty ounces pass 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 accumulating 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 God.
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 diaphoretic 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 illustration of the exercise of the latter function in the vaccination of children and others, to protect them from small-pox. A small quantity 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 quantity 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 washing 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 assumed 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 quantity 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 coarse 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 coarse 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.
By an act of the Legislature of the commonwealth of Massachusetts, passed 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 sexes, 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.
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 constitutions; 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 circumstances, 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 diminishing 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 constitution 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 coarse 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 constitution; 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 principal 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 accumulated perspiration of the day to pass 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 institutions 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 accumulate in them, it may be reabsorbed, and, passing 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 unobjectionable. 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 accumulation of tartar, which so commonly incrusts neglected teeth. If suffered to remain, it gradually accumulates, 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 appetites 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 principal 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 constitutes 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.
The Bones.—The bones constitute the frame-work of the system. They consist of two substances, being formed of both animal and earthy matter. To the former belongs every thing connected with their life and growth, while the latter gives to them solidity and strength. The proportions of the animal and earthy elements of which the bones are composed vary at different ages. In childhood and early youth, when but little strength is needed, and great growth of bone is required, the animal part preponderates. As growth advances the animal part decreases, and the earthy part increases. In middle life, when growth is finished and the strength is greatest, and when nutrition is required only to repair waste, the proportions are changed, and the solid or earthy part exceeds the vital or animal; and in extreme old age, the earthy part so predominates as to cause the bones to become very brittle.
The bones, like other parts of the system, require exercise. If properly used, they increase in size and strength. But while a due degree of exercise is beneficial, it ought to be remarked that severe and continued labor should not be required of children and youth; for its tendency is to increase the deposition of earthy matter to a hurtful extent. It is by this means that many children are made dwarfs for life, their bones being consolidated by an undue amount of exercise and excessive labor before they have attained their full growth. Multitudes of children in our country, from this and kindred causes, fail of attaining the size of their ancestors. These remarks may be turned to a practical account in the family and in the school. At birth, many of the bones are scarcely more than cartilage; yet children are frequently urged to stand and walk long before the bones become sufficiently strong to sustain the pressure; and, as a consequence, their legs become crooked, and they are perhaps other ways deformed for life. Children ought always, when seated, to be able to rest their feet upon the floor. When they occupy a seat that is too high, and especially when they are unable to reach their feet to the floor, the thigh bones very frequently become curved. If, in addition to high seats, the back is not supported, children become round shouldered, their chests contract, their constitutions become permanently enfeebled, and they become peculiarly susceptible to pulmonary disease. The back to the seat should afford a pleasant and agreeable support to the small of the back, but it ought not to reach to the shoulder blades.
Parents and teachers should never forget that children are as susceptible to physical training as to intellectual or moral culture. And here, especially, they should be "trained up in the way they should go." Physical uprightness is next to moral. If children are allowed to contract bad physical habits, they are liable not only to grow crooked, but to become deformed in various ways. But so great is the power of education, that by it even the physically crooked may be made straight; the chest may be enlarged, the general health may be improved, and much may be done in many ways to fortify those who have inherited feeble constitutions against the attacks of disease. The benefits resulting from maintaining an upright form, and a free and open chest, have already been considered, and I shall have occasion to refer to them again. The chest of most adults, although incased with bone, may be increased several inches by drawing the arms back in the use of nature's own shoulder-braces, and at the same time taking deep inhalations of air, and filling the lungs to their utmost capacity. Hundreds of individuals in different parts of the country have borne testimony to the efficacy of this treatment in the improvement of their health. The good results of such discipline in childhood are still more manifest.
A stooping posture is frequently induced by sitting at tables and desks that are too low. It has been erroneously maintained by some that the top of the desk should be on the same plane with the elbow when the arm hangs by the side. When the desk is higher, it has been said the tendency is to elevate one shoulder, to depress the other, and to produce a permanent curvature of the spinal column. Although this may have been frequently the result of sitting at a high desk, yet it is not a necessary result. To prevent the projection of one shoulder, and the consequent spinal curvature, both of the arms must be kept on the same level. For this purpose, there should be room to support them equally; and care should be taken to see that this support is regularly sought. If this be not done, the right arm will be apt to rise above the left, from its more constant use and elevation. A physician, highly celebrated for the success that has attended his treatment for lung affections, after dwelling upon the injury to the health that frequently results from sitting at too low desks, remarks, that "every parent should go to the school-rooms, and know for a certainty that the desks at which his children write or study are fully up to the arm-pits, and in no case allow them to sit stooping, or leaning the shoulders forward on the chest. If fatigued by this posture, they should be called to stand, or go out of doors and run about." The height of table I find most conducive to comfort for my own use is midway between the two; that is, half way from the elbow (as the arm hangs by the side) to the arm-pit. It is necessary, however, to rest both arms equally upon the table. The secret of posture consists in avoiding all bad positions, and in not continuing any one position too long. The ordinary carriage of the body is an object worthy of the attention of every parent and instructor. The more favorable impression which a man of erect and commanding attitude is sure to make, should not be overlooked. But there is a greater good than this; for he who walks erect, enjoys better health, possesses increased powers of usefulness, realizes more that he is a man, and has more to call forth gratitude to a beneficent Creator, than he who adopts an oblique posture. It was just remarked that "physical uprightness is next to moral." Physical obliquity, it may be added, is akin to moral. If they are not German-cousins, there can be little doubt but that, considered in all its bearings, the tendency of the former is to induce the latter.
Important as an erect posture and a well-developed chest are to gentlemen, they are in some respects even more so to the fairer sex; for, in addition to the advantages already considered, which both enjoy in common, these impart to them a peculiar charm, that to men of sense is far greater than pretty faces, which Nature has not given to all. "For a great number of years, it has been the custom in France to give young females, of the earliest age, the habit of holding back the shoulders, and thus expanding the chest. From the observations of anatomists lately made, it appears that the clavicle or collar bone is actually longer in females of the French nation than in those of the English. As the two nations are of the same race, as there is no remarkable difference in their bones, and this is peculiar to the sex, it must be attributed, as I believe, to the habit above mentioned, which, by the extension of the arms, has gradually produced an elongation of this bone. Thus we see that habit may be employed to alter and improve the solid bones. The French have succeeded in the development of a part in a way that adds to health and beauty, and increases a characteristic that distinguishes the human being from the brute."[9]
The Muscles.—The muscles consist of compact bundles of fleshy fibers, which are found in animals on removing the skin. They constitute the red fleshy part of meat, and give form and symmetry to the body. In the limbs they surround and protect the bones, while in the trunk they spread out and constitute a defensive wall for the protection of the vital parts beneath. The muscles have been divided into three parts, of which the middle and fleshy portion, called the belly, is most conspicuous. The other two parts are the opposite ends, and are commonly called the origin and insertion of the muscle. The origin is usually fastened to one bone, and the insertion is attached to another. By the contraction of the belly of the muscle, the insertion, which is movable, is drawn toward the origin, which is fixed, and brings with it the bone to which it is attached. This any one can see illustrated in bending the arm. The muscle which performs this function lies between the elbow and the shoulder. It is attached to the shoulder by its origin, and to one of the bones of the fore-arm, just below the elbow, by its insertion. By grasping the arm midway between the shoulder and the elbow with the opposite hand, and then bending the arm, the enlargement of the belly of the muscle by the contraction will be at once perceived. Then, by moving the hand down on the inside of the arm toward the elbow, the lessening muscle may be readily traced until it terminates in a tendon, of much less size than the muscle, but of great strength, which is inserted into the bone just below the elbow. As the fore-arm is drawn up, and especially if there be a weight in the hand, the tendon may be felt just within the elbow-joint, running toward the point of insertion. Extend the arm at the elbow, and the muscle on the outside of the arm will swell and become firm, while the inside muscle, and its tendon at the elbow, will be relaxed. This example well illustrates the principle on which all the joints of the system are moved. Those who are acquainted with mechanics will readily perceive that the action just described is an example of the "third kind of lever," where the power is applied between the weight and the fulcrum. The elbow is the fulcrum, the hand contains the weight, and the tendon, inserted into the bone just below the elbow, is the power. This kind of lever requires the power to be greater than the weight, and acts under what is called a mechanical disadvantage. What is lost in power, however, is compensated in increased velocity.
There are upward of four hundred muscles in the human body. Some of these are voluntary in their motions, as those I have described, while others are involuntary, as the action of the heart and the respiratory muscles. Had the action of these depended upon the will, as does the action of the muscles of locomotion, the circulation of the blood and the process of breathing would cease, and life would become extinct whenever sleep or any other cause should overcome the attention. Here, then, we have another beautiful illustration of the wisdom and beneficence of the Creator in so ordering that those muscles which are essential to the continuation of life shall perform their functions without the control or attention of the individual.
The study of the muscular system involves an exposition of the principles by which exercise should be regulated, and can scarcely fail to excite the attention of the general reader, and especially of those who, as parents or teachers, are interested in the education of the young.
The muscles enable us to move the frame-work of the system. Their chief purpose obviously is to enable us to carry into effect the various resolutions and designs which have been formed by the mind. But, while fulfilling this grand object, their active exercise is, at the same time, highly conducive to the well-being of many other important functions. By muscular contraction, the blood is gently assisted in its course through the smaller vessels to the more distant parts of the body; and by it the important processes of digestion, respiration, secretion, absorption, and nutrition are promoted; and by it the health of the whole body is immediately and greatly influenced. The mind itself is exhilarated or depressed by the proper or improper use of muscular exercise. It thus becomes a point of no slight importance to establish general principles by which that exercise may be regulated.
In every part of the animal economy, the muscles are proportioned in size and structure to the efforts required of them. Whenever a muscle is called into frequent use, its fibers increase in thickness within certain limits, and become capable of acting with greater force and readiness. On the other hand, when a muscle is little used, its volume and power decrease in a corresponding degree.
In order to secure the most beneficial results from exercise, reference should be had to the time at which it is taken. Those who are in perfect health may engage in it at almost any hour except immediately after a meal; but those who are not robust ought to confine their hours of exercise within narrower limits. To a person in full vigor, a good walk, or other brisk exercise before breakfast may be highly beneficial and exhilarating, while to an invalid or delicate person it will be likely to prove detrimental. In order to prove beneficial, exercise must be resorted to only when the system is sufficiently vigorous to be able to meet it. This is usually the case after a lapse of from two to four hours after a moderate meal. The forenoon, then, will generally be found the best time for exercise for persons whose habits are sedentary. If exercise be delayed till the system feels exhaustion from want of food, its tendency will be to dissipate the strength that remains and impair digestion; while, if taken at the proper time, it will invigorate the system and promote digestion. The reasons are obvious; for exercise of every kind causes increased action and waste in the organ, and if there be not materials and vigor enough in the system to keep up that action and supply the waste, nothing but increased debility can reasonably be expected.
Active exercise immediately before meals is injurious. The reasons are apparent, for muscular exercise directs a flow of blood and nervous energy to the surface and extremities; and it is an established law in physiology, that energetic action can not be kept up in two distant parts of the system at the same time. Hence, whenever a meal is taken immediately after vigorous exercise, the stomach is taken at disadvantage, and, from want of the necessary action in its vessels and nerves, is unable to carry on digestion with success. This is very obviously the case where the exercise has been severe or protracted.
Active exercise ought to be equally avoided immediately after a heavy meal, for then the functions of the digestive organs are in the highest state of activity. If the muscular system be called into vigorous action under such circumstances, it will cause a withdrawal of the vital stimuli of the blood and nervous influence from the stomach to the extremities, which can not fail greatly to retard the digestive process. In accordance with this well-established fact, there is a natural and marked aversion to active pursuits after a full meal. A mere stroll, which requires no exertion and does not fatigue, will not be injurious before or after eating; but exercise beyond this limit is at such times hurtful. All, therefore, who would preserve and improve their health, will find it to their advantage to observe faithfully this important law, otherwise they will deprive themselves of most of the benefits that are usually attendant upon judicious exercise. All, then, who are forced to much exertion immediately after eating, should satisfy themselves with partaking of a very moderate meal. These remarks apply to both physical and mental exercise; for if the intellect be intently occupied in profound and absorbing thought, the nervous energy will be concentrated in the brain, and any demands made on it by the stomach or muscles will be very imperfectly attended to. So, also, if the stomach be actively engaged in digesting a full meal, and some subject of thought be presented to the mind, considerable difficulty will be felt in pursuing it, and most probably both thought and digestion will be disturbed.
Another law of the muscular system requires that relaxation and contraction should alternate; or, in other words, that rest should follow exercise. In accordance with this law, it is easier to walk than to stand; and in standing, it is easier to change from one foot to the other than to stand still. To require a child to extend his arm and hold a book in his hand, or even to keep the arm extended but a short time, is a violation of this law which should never be permitted. Akin to this is the very injudicious practice, which is sometimes resorted to in schools, of requiring a boy to stoop over, and, placing his finger upon a nail in the floor, "hold it in." Teachers who are disposed to inflict punishments like these ought first to try the experiment themselves. Such protracted tension of the muscles enfeebles their action, and ultimately destroys their power of contraction.
These remarks sufficiently explain why small children, after sitting a while in school, become restless. Proper regard for this organic law requires that the smaller children in school be allowed a recess as often, at least, as once an hour; and that all be allowed and encouraged frequently to change their position. I fully concur in the opinion expressed by Dr. Caldwell, who says, "It would be infinitely wiser and better to employ suitable persons to superintend the exercises and amusements of children under seven years of age, in the fields, orchards, and meadows, and point out to them the richer beauties of nature, than to have them immured in crowded school-rooms, in a state of inaction, poring over torn books and primers, conning words of whose meaning they are ignorant, and breathing foul air."
A change of position calls into action a different set of muscles, and relieves those that are exhausted. The object of exercise is to employ all the muscles of the body, and especially to strengthen those that are weak. It ought hence to be frequently varied, and always adapted to the peculiarities of individuals. Different kinds of exercise will therefore be found to suit different constitutions. Sedentary persons best enjoy, and will be most profited by, that kind of exercise which brings into action the greatest number of muscles.
To give exercise its greatest value, it should be taken at the same hour every day. This is well-nigh as important as the rule that requires meals to be taken regularly. If exercise be taken irregularly, one day in the morning, another day at noon, and another day at night, if at all, it is possible that good may result from it, but its beneficial effects would be greatly increased if the same amount of exercise were taken every day at the same hours. Give the system an opportunity of establishing good habits in this respect, and it will derive great advantage from them; but it is difficult for it to derive any benefit from a habit of irregularity, if such may be called a habit. Students, teachers, and all persons who lead sedentary lives, should have their regular times for exercise as well as for meals, and if they find it necessary to do without one, they will generally find it advantageous to dispense with the other also.
Walking, it has been said, agrees with every body. But as it brings into play chiefly the lower limbs and muscles of the loins, and affords little scope for the play of the arms and muscles of the chest, it is of itself insufficient to constitute adequate exercise. To render it most beneficial, the shoulders should be drawn back, and the chest should be enlarged by taking deep inspirations of pure air. The muscles of the chest, and of every part of the body, should be free to move and unconfined by tight clothing. Fencing, shuttlecock, and such other useful sports as combine with them free movements of the upper part of the body, are doubly advantageous, for they not only exercise the muscles of the whole body, but possess the additional advantage of animating the mind and increasing the nervous stimulus, by which exercise is rendered easy, pleasant, and invigorating. For the purpose of developing the chest, physiologists generally concur in recommending fencing as a good exercise for boys. Shuttlecock is a very beneficial exercise for females, calling into play, as it does, the muscles of the chest, trunk, and arms. It ought to be practiced in the open air. When played with both hands, as it may be after a little practice, it is very useful in preventing curvature, and in giving vigor to the spine. It is an excellent plan to play with a battledore in each hand, and to strike with them alternately. The graces is another play well adapted for expanding the chest, and giving strength to the muscles of the back, and has the advantage of being practicable in the open air. It is very important that the muscles of the back be strengthened by due exercise, for their proper use contributes to both health and beauty.
When managed with due regard to the natural powers of the individual, and so as to avoid effort and fatigue, reading aloud becomes a very useful and invigorating exercise. In forming and undulating the voice, not only the chest, but also the diaphragm and abdominal muscles are in constant action, and communicate to the stomach and bowels a healthy and agreeable stimulus. Where the voice is raised and the elocution is rapid, the muscular effort becomes fatiguing; but when care is taken not to carry reading aloud so far at one time as to excite a sensation of soreness or fatigue in the chest, and the exercise is duly repeated, it is extremely useful in developing and giving tone to the organs of respiration and to the general system.
"Vocal music is also very useful, by its direct effect on the constitution. It was the opinion of Dr. Rush, that young ladies especially, who, by the custom of society, are debarred from many kinds of salubrious exercise, should cultivate singing, not only as an accomplishment, but as a means of preserving health. He particularly insists that it should never be neglected in the education of females; and states that, besides its salutary operation in enabling them to soothe the cares of domestic life, and quiet sorrow by the united assistance of the sound and sentiment of a properly chosen song, it has a still more direct and important effect. 'I here introduce a fact,' he remarks, 'which has been suggested to me by my profession, and that is, that the exercise of the organs of the breast by singing contributes very much to defend them from those diseases to which the climate and other causes expose them. The Germans are seldom afflicted with consumption, nor have I ever known but one instance of spitting blood among them. This, I believe, is in part occasioned by the strength which their lungs acquire by exercising them frequently in vocal music, for this constitutes an essential branch of their education. The music-master of our academy has furnished me with an observation still more in favor of this opinion. He informed me that he had known several instances of persons who were strongly disposed to consumption, who were restored to health by the exercise of their lungs in singing.'"[10]
Bathing or ablution, when conducted as recommended on pages 60 and 61, is not only a means of cleanliness and of exciting a healthy action in the skin, but it constitutes, at the same time, a most admirable exercise. If a lodging-room has been properly ventilated by leaving open windows, or otherwise, so that the air is pure and healthful in the morning, ten or fifteen minutes spent in bathing and friction, with a proper exercise of the muscles of the back and abdomen, will contribute more to invigorate the system and promote the general health than twice the amount of exercise taken at any other time or in any other way.
From the foregoing remarks, it appears that the most perfect of all exercises are those which combine the free play of all the muscles of the body, mental interest and excitement, and the unrestrained use of the voice.