The strainer for a milk-pail is preferably made of cheesecloth, since this can always be easily boiled between milkings, and so sterilized. A wire strainer through which the milk has to pass, and where the milk is often stirred by the finger of the milker to make it pass through more rapidly, is in no sense as satisfactory as cheesecloth.

The straining should be performed as soon as each pail is filled with milk, and pails of milk should never be allowed to stand around in the barn back of the cows, but rather should be taken at once to the milk-room, where it can be strained before any further contamination takes place.

Then the milk should be cooled, and this, to be effective, must be done in such a way that the temperature of the milk shall at once fall to fifty degrees or less. It is well known that a forty-quart can of milk lowered into spring water cools slowly on the outside, but that hours will pass before the inside of the can has its temperature lowered appreciably. Meanwhile, bacterial growth has started, and that milk can never be as good as when cooled quickly throughout. Special apparatus is made in which the milk is spread out in very thin sheets over a surface cooled by ice or cold water to a low temperature. In this way all the milk is at once lowered in temperature and may then be kept in spring water until time for shipment. Many examples can be given of the value of this kind of cooling. A few years ago, the Cornell University Agricultural Experiment Station determined that a certain milk when fresh contained, about 4000 bacteria per c.c., and fifteen hours later at room temperature had 270,000, and twenty-seven hours later had soured with an innumerable number of bacteria. Another part of the same milk, however, kept at fifty degrees Fahrenheit, showed absolutely no increase in bacteria for twenty-seven hours, and was still sweet with only 12,000 bacteria at the end of three days.

City milk.

The value of pure milk is not a matter of individual opinion on the part of the farmer, but it is a vital point with thousands and millions who are dependent upon the farmer for this life-giving food. Unfortunately, to-day the relation between the consumer and the milkman is so remote that it is almost lost sight of, and in place of the personal relationship which formerly existed, which made the milkman proud of his milk and the consumer proud of her milkman, there is to-day an absolute disregard of the interests of the other side in almost all cases. Even in the smaller cities, consolidated milk companies are being established by which the former independent milkmen are bringing milk to the central station in large cans, where it is dumped into vats along with the milk from a dozen other milkmen. Some may be good and some bad, but what is the use, each one says, of my taking particular pains when my neighbor produces milk of such poor quality? The result is that it is all far from good and likely to deteriorate rather than to improve. To be sure, at the central station it is bottled and distributed to the consumer in apparently clean glass jars, but this is not the same cleanliness that one gets when the bottling is done five minutes after the milk comes from the cow.

When the milk supplied to the larger cities is furnished as in New York, the impossibility of controlling the quality of the supply becomes apparent. The farmer brings to the shipping station his two or three large cans of milk, representing the night's and morning's milkings. These are loaded on a train along with hundreds of others, a few chunks of ice are thrown on top, and the train is started for New York, from points as far as two hundred and fifty miles away, reaching the city in the early evening. There it is received and hauled to milk stations, where it is distributed in different-sized cans and bottles, and the next morning, thirty-six hours old, distributed to the babies of the city as fresh milk. Thanks to the energetic inspection practiced by the officers of the Department of Health of New York City, who have emptied hundreds of quarts of milk into the city gutters merely because the temperature of the milk was higher than that prescribed, the quality of the milk is not so bad as it might be. In fact, the writer has bought apparently good milk on Long Island, shipped down from New York City, because the local supply was deficient in quantity and inferior in quality, although the latter would naturally be supposed to be fresh and the other was certainly forty-eight hours old on its receipt.

Cleanliness and care are the two watchwords for good milk, and both practices ought to be observed faithfully by the milk producer, whether he has in mind the health of his own family or the health of the dwellers in the city hundreds of miles away.

Dangers of diseased meat.

Next to milk, the product of the farm which has most to do with the health of those to whom farm products are sent is the meat which comes from the cows, sheep, and pigs, and makes a large part of the farmer's produce. To be sure, the amount of meat thus sent to market from the farm is by no means as great as in former years, since even the smallest village to-day has representatives of Swift and Co., Schwartzman and Sulzenberger, Jacob Dold, and others of the great western packing houses. There is still, however, a great deal of local butchering, and it is important that the farmer himself should know the characteristics of meat and should be so impressed with the dangers of diseased meat that the temptation to unload a bad carcass on the unsuspecting public may be overcome. There is nothing more certain in sanitary science than that the application of heat destroys animal parasites and micro-organisms, so that, except for diminishing the nutritive value, there is comparatively little real danger in eating diseased meat when cooked, and the fearful ravages of bad ham have been largely due to occasions where the ham has been eaten raw or semi-raw.

There are two points to be noted in an animal about to be killed, namely, whether the animal is healthy, that is, free from disease,—and whether it is in proper condition, neither too young nor too old, is well-grown and well-nourished. Among the diseases to which animals are subject, some are objectionable because of the possibility of the direct transmission of their disease to those eating the flesh, while others are objectionable because the flesh is spoiled and so causes irritation in the stomach and intestines of those eating it. Among the former diseases may be mentioned trichinosis, tuberculosis, and measles of pigs. In the latter category are animals suffering from such diseases as epidemic pneumonia, foot-and-mouth disease, Texas fever, anthrax, hog cholera, and others in which a general toxic condition of the animal's system results from the disease. Toxins are thus formed in the body which may pass to the human being eating the flesh, and in this way poisons called ptomaines are produced, resulting in so-called toxic poisoning. It is not the function of this book to describe the symptoms peculiar to each of these diseases, and it is here sufficient to say that the flesh of no animal apparently suffering from any disease should be used for food.

The unhealthy animal can usually be recognized by a casual examination, without undertaking to define the specific disease from which the animal is suffering, characterized by such an examination. When sick, according to Parkes, the coat of the animal is rough or standing, the nostrils are dry or covered with foam, the eyes are heavy, the tongue protrudes, the respiration is difficult, the movements are slow and uncertain, and the various organs of the body perform their functions abnormally. On the other hand, the healthy animal moves freely, has a bright eye and moist nostril and a clear skin, the respiration is not hurried and the breath has no unpleasant odor, the circulation is tranquil, and the appetite good, thirst not excessive, and, if ruminant, when in repose, chews the cud.

There is, however, one exception to this general rule, and that is in the case of tuberculosis, since the most scientific observations have failed to trace any connection between the inception of tuberculosis in man and the eating of meat from tuberculous animals, or to show any evil effects to man from eating the flesh of cows affected in the first stages of tuberculosis. The regulations of the United States Department of Agriculture on this point are as follows:——

"All carcasses affected with tuberculosis and showing emaciation shall be condemned. All other carcasses affected with tuberculosis shall be condemned, except those in which the lesions are slight, calcified, or encapsulated, and are confined to certain tissues ... and excepting also those which may ... be rendered into lard or tallow."

The regulations referred to say in substance that when the lesions occur in a single part of the body, as in the neck, liver, lungs, or in certain specified combinations, the meat may be used; but that where the lesions affect more than one or two parts of the body, the carcass must be rendered at a temperature of not less than 220 degrees Fahrenheit for four hours into lard or tallow.

This really means that an animal only slightly affected with tuberculosis, where the lesions are slight and are confined to the tissues of certain organs only, may be used for food. This has been decided only after very careful reading of all known facts, and is particularly important in view of the opposition to the use of milk of tuberculous cows. The tuberculin test, on which depends the determination of tuberculosis in cows, is so delicate that a very slight lesion is sufficient to cause a reaction. The lesions are so slight as in many cases to be entirely overlooked by the ordinary butcher. The United States regulations allow such a carcass to be butchered and used for food after the cow has been condemned by the tuberculin test as a milk-producing animal. This does not mean, of course, that those parts of the body affected by the tuberculosis lesions shall be used, but, since these lesions are usually segregated, they can readily be cut out without reference to the rest of the body.

The other point to be noted in selecting or rejecting animals for slaughter is their general condition. This means that they should be of the proper weight,—that is, not emaciated, but with a proper amount of fat,—that the flesh should be firm and elastic and the skin supple. Nor should they be either too young or too old. A prominent example of the first error is in the sale of calves under three weeks old, known as "bob-veal," and while some sanitarians will not object to eating calves under three weeks old, the consensus of opinion is that to be fit for food a calf should be at least that age. Fortunately, it is for the interest of the butcher to hold the calf until it has arrived at a certain weight, and the stringent laws of most states prohibiting the sale of bob-veal make it dangerous and expensive for the farmer to slaughter young calves unless they are of the right age.

The most common example of the direct transmission of disease from animals to men is through the development of the parasite in a pig, known as "trichinosis." This disease is due to a minute worm scarcely visible to the naked eye which lives in the muscles of men, dogs, swine, and other animals, and also under other conditions in their intestines. Millions of the young trichinae may live in the flesh of a pig without producing any particular difference in the appearance of the flesh. After four or five weeks, they become incased in small white spherical capsules which later, after a year or so, become entirely calcified. In this form they live for years in the flesh of the pig and do no harm in that condition. If, however, this flesh be eaten by man without being cooked so thoroughly as to destroy the little worm (about one twenty-fifth of an inch long) which has been living in these capsules, then they become distributed around the stomach of the person eating that flesh, enter the intestines, and attach themselves to the membranes there. They grow very rapidly, and broods of from 500 to 1000 young worms are produced from each one of the entering worms, and, since there may be a quarter of a million or more in an ounce of pork, it is not surprising that the total number deposited in the intestines from a single meal of raw pork is enough to produce great distress, characterized by vomiting and diarrhea. Fortunately, the disease is not necessarily serious, since after the development of the young worms (and it is at this period when the suffering of the human patient is at its height), the worms begin to form capsules again, as in the pig, and when inclosed, are again inocuous. Professor Sedgwick says that persons in robust health may be able to survive the attack of half a million or more of these flesh worms and recover, but there is a limit to human endurance, and the numbers often contained in the muscles of man from this source are almost incredible. In some severe cases, the numbers contained in human bodies have been estimated by reliable authorities to be as high as forty to sixty millions. Not long ago, the writer was impressed with the severity of this disease by having brought to his attention an epidemic in a herd of swine caused, presumably, by feeding waste which contained rinds of Western pork, infected with trichinae and many examples may be found of regular epidemics caused by persons eating raw ham infected with this disease. Fortunately the means of prevention is very simple and implies merely the thorough cooking of the meat. If persons will avoid eating raw or underdone swine flesh in any of its varieties, no danger need be apprehended.

In general, it should be remembered that any animals dying of diseases are not fit for food, and this applies to all animals, from the largest to the smallest. Animals dying by accident, of course, are exceptions, but if diseased animals, animals dying a natural death, and animals out of condition are eliminated, the quality of food supplied from any individual farm may be approved so far as the animal itself is concerned.

The slaughter-house.

There is, however, the further question of the sanitary condition of the slaughter-house and the care of the meat after being dressed. It may be that one gets accustomed to the sight of the filthy barns or out-houses so often used for slaughtering. Places infected with flies and other insects, overrun with rats, and the effluvia of which is easily noticeable at a distance of half a mile, are not uncommon and suggest their own condemnation. While it is not possible to directly associate any particular disease with such a condition of the slaughter-house, yet such conditions must result in a rapid development of putrefactive bacteria, in the deposit by flies of different micro-organisms brought from the festering heaps of offal and manure in the vicinity, and must prevent the maintenance of the flesh in the clean and wholesome condition in which it may have been up to the time of hanging in such a place. A well-kept slaughter-house will have the ceilings, side walls, and partitions frequently painted, or else scrubbed and washed. The floor of the building, particularly, should be made water-tight, with proper drains so that the blood shall not remain on the floor to saturate the wood and develop decay. An abundance of clean water should be provided, so that the area may be thoroughly washed as often as used, with proper drains provided for carrying away the dirty water. The ventilation of the building should be complete, and provision should be made for lifting and moving carcasses without handling.

In most small slaughter-houses, the obnoxious practice prevails of maintaining a herd of swine to consume the entrails of the slaughtered animals, and a more fearsome and disgusting spectacle than a dozen lean, active hogs fighting over recently deposited entrails and wallowing up to their bellies in filth can hardly be imagined. Nor is this any fanciful picture. The writer has seen it over and over again, the income from the hogs thus fed being one of the principal assets of the establishment. Such hog meat is not fit for food. The refuse from the slaughter-house ought to be carried away and buried; its fertilizing value will not be lost if it be put in the garden, and the effect of the prompt removal of this refuse will be to improve the character of the entire slaughter-house.



CHAPTER XII

FOODS AND BEVERAGES

Before discussing the question of suitable foods for individual needs or the ill-health which is so likely to follow an unrestrained or unwise diet, it will be well to trace briefly the passage of food through the human body, with the various changes which take place in its mass from the time it enters the mouth until it is absorbed by the stomach.

The human mechanism.

In a little book by Hough and Sedgwick entitled "The Human Mechanism," the authors point out that in many respects the human body is like any machine developing energy by the conversion of certain kinds of raw material. Thus, as the steam engine will use up coal in the development of mechanical energy, so the human body will absorb food and convert it into vital energy, and it is quite as important that the human body shall have its source of energy properly adjusted to its needs as that the steam engine shall be fired with coal possessing a reasonable amount of heat-producing particles.

The human body requires this supply of raw material for several different purposes. In the first place, the very fact of living uses up each minute a number of cells of various kinds in various organs. Each breath taken, each heart beat, each muscular motion, all tend to the destruction of tissue and involve its reconstruction. Violent exercise uses up cell tissue very rapidly, so much so that a football player will commonly lose from five to ten pounds in weight during a well-contested game. It is a fundamental principle of training for any athletic event involving hard exercise, that suitable food in large quantities must be provided, and a young man training for football or rowing will eat beefsteak, eggs, and other hearty food to an astonishing amount, all of it going chiefly to repairing worn-out and used-up tissue.

In the second place, food is needed to supply material for growth, and so it is that a growing boy eats out of all proportion to his size, and the fact that he seems to be, as it is said, hollow clear to his feet, is only his rational endeavor to supply the material needed for his growing body.

In the third place, food must be supplied for the work to be done by the body, as distinguished from the loss of tissue due to the performance of the work, and finally, food must be provided in order to maintain the bodily temperature, a larger amount being naturally required where the difference between the temperature of the body and the outside air is very great, as in the Arctic regions.

The human body being a special kind of machine, the raw material supplied must be adapted to the needs of the machine, and while a lump of coal admirably supplies energy for a steam boiler, no one would think of feeding a lump of coal to a human being, simply because, by experience, we know that suitable energy is not thereby developed. In the matter of suitability of foods, much depends upon the local supply. It is not to be supposed, for example, that the Eskimos eat meat and fat altogether because it is the best article of food for them, but rather because it is the only food available. It would be foolish to prescribe fresh fruit or even white bread for the Eskimos because it is out of the question for them to get such food. But, in general, it is possible for the average individual to choose his supply of raw material in accordance with the needs which his experience has pointed out and with the teachings of scientific investigators on this subject. Raw material, however, is not converted into energy by any simple operation. The human body is made capable of taking raw material of most varied kinds and transforming it into nutriment capable of being absorbed by the system and made over into cell tissue. It will be worth while to indicate the steps of this complex process.

Digestive processes.

The mouth plays the first part in the scheme of transformation, and here two operations are performed. First the food is crushed and ground by the teeth, exactly as when, in some chemical processes, a fine grinding is essential for the subsequent transformation. In this country, this preliminary process is often sadly neglected, so much so that a distinguished investigator, named Horace Fletcher, has, within the last few years, established a school for the cultivation of the habit of chewing, with the idea that if this practice could be encouraged and at least twenty chews taken with every mouthful, the health of the individual would be vastly improved and sick persons even cured merely through this practice.

The other function of the mouth is to mix with the food the saliva which drops from small glands in the back of the mouth into the food. The action of the saliva is partly to lubricate the food, so that it will slip down easily, and no better proof of this can be found than trying to eat a cracker rapidly without chewing. But it also acts on starch which is not digested easily unless mixed with this ferment. The action of the saliva on starch is to convert it into sugar, which is easily absorbed later on. Curiously enough, most persons would be more apt to chew a piece of meat thoroughly than to chew a piece of bread, and yet the meat contains practically no starch and therefore does not need the action of the saliva, whereas bread is chiefly made up of starch and therefore needs the saliva as an essential for digestion.

The food then passes down into the stomach, which is a sort of storehouse, preparatory to the really important steps in digestion. Here, the food is acted upon by another element known as gastric juice, which is supplied by small glands found in the membrane of the stomach. The mixture of food and gastric juice is made very thorough by the continual agitation of the food, so that the mass is softened as well as thoroughly mixed. The effect of the gastric juice is to act upon that portion of food known as proteids. Examples of almost pure proteids are found in the fiber of beef and other meat, in the yolk of eggs, and in cheese. Some vegetables, such as peas, also contain large quantities, and coarse flour and oatmeal contain considerable percentages. The effect of the gastric juice on this proteid matter is to break up the complex molecules into small molecules which then pass into solution, making the mass leaving the stomach a uniformly mixed semiliquid substance of about the consistency of thick pea soup. The food then enters the smaller intestine, at the beginning of which the juices from the pancreas are added. The pancreas is a gland which furnishes a strongly alkaline liquid neutralizing the acid of the gastric juice, so that the gastric agent, pepsin, loses its power. From this gland comes a material which can act on all kinds of food and which is by far the most important of the digestive juices.

When thoroughly mixed with the bile and pancreatic juice, the contents of the intestine are gradually absorbed, in so far as their condition allows, by the surface of that organ and are carried away by the ducts designed for that purpose to the various organs, while that part not suited for absorption is eliminated.

Teachings of the digestive operations.

The matter of hygienic eating, therefore, consists in supplying the various organs, the mouth, the stomach, and the smaller intestine with proper food in proper quantity, so that the body itself may be properly nourished from the food supplied. A great deal of scientific investigation in this connection has been made to ascertain any relation which may exist between the different kinds of food and their availability for the body. Scientists have divided all food into four classes, namely, proteids, carbohydrates, fats, and inorganic salts, and they have agreed on the following general statements with reference to these four classes. Examples of almost pure proteids have already been given, and it may here be added that carbohydrates are typically shown by the starchy particles found in potatoes or wheat. Chemically, the difference consists in the fact that proteids contain nitrogen whereas carbohydrates do not. Fats are self-explanatory, and the group of inorganic salts includes such material as salt, lime, phosphates, and other minerals needed by the body but not requiring digestion.

Just what function each one of these four groups plays in the nutrition of the human body is not definitely understood, but it seems that the proteids are particularly useful in building up cell tissue, that the carbohydrates are particularly useful in providing for muscular energy, that the fats are particularly useful in keeping up the normal warmth rather more by laying on a blanket of fat over the bones than in actually consuming the food in the creation of heat. These statements are not absolute, since experiments have shown that some tissue-building can go on even if proteids are rigorously excluded from the diet, and on the other hand that muscular work, while accompanied by a large consumption of carbohydrates in the body, may come from proteids entirely. This may explain why men can live and even do a reasonable amount of work eating meat and fat altogether, as in the Arctic regions, or dry bread and fruit in other regions, the above facts being complicated by the influence of muscular exercise on the activity of the digestive system.

No principle of hygiene is better established than that men undergoing hard physical exercise need and will take care of a larger amount of coarse food than those occupied in sedentary work. In cold weather what is required is not really more fat as food, but more food. It has been found that there is a limit to the amount of meat food which the body can absorb, and, further, that the excess is not easily disposed of, as with starchy food, and tends to load up the liver and other organs with the waste products, resulting in general disturbances of the whole body. It is commonly known, for instance, that high-livers, as they are called, are likely to be troubled with diseases like indigestion, rheumatism, or gout,—diseases which are the result of overburdening those organs just mentioned.

Balanced rations.

TABLE XVI

================================+==================================== WEIGHT IN GRAMMES CONDITION + - - Proteid Fat Carbohydrates - - Child up to 1-1/2 years (average) 0.71-1.27 1.06-1.59 2.12-3.18 Child from 6 to 15 years (average) 2.47-2.82 1.30-1.76 8.82-14.10 Man (moderate work) 4.16 1.98 17.63 Woman (moderate work) 3.24 1.55 14.10 Old man 3.53 2.40 12.34 Old woman 2.82 1.76 9.18 Atwater (man, light exercise) 3.70 3.70 13.3 Chittenden (man, light exercise) 2.16 2.83 13.0 ================================================================

A well-designed food ration, therefore, will be one which will provide the body with the proper amount of food material wisely adjusted to the occupation and the digestive ability of the individual. It has been, in the past, a matter of very exact computation to determine how many ounces of proteid food, how many ounces of starchy food, and how many of fatty foods should be consumed during the day, and experiments have been made in asylums, prisons, and on companies of soldiers with a view to proving the theoretical figures.

It has always been found that an overdose of proteids results in inability to absorb the excess, and it has been assumed that a ratio of proteids to carbohydrates of one to four is approximately the proper proportion. For instance, Koenig (1888) shows the minimum daily need of food stuffs at different ages and two American authorities, Atwater and Chittenden, have also laid down standards; all three being shown in the preceding table.

The following table taken from Rough and Sedgwick's book, already referred to, gives the percentage composition of some of the more common foods:—

TABLE XVII

========================================= Water Proteid Starch Sugar Fat Salts - - - Bread 37 8 47 3 1 2 Wheat flour 15 11 66 4.2 2 1.7 Oatmeal 15 12.6 58 5.4 5.6 3 Rice 13 6 79 0.4 0.7 0.5 Peas 15 23 55 2 2 2 Potatoes 75 2 18 3 0.2 0.7 Milk 86 4 5 4 0.8 Cheese 37 33 24 5 Lean beef 72 19 3 1 Fat beef 51 14 29 1 Mutton 72 18 5 1 Veal 63 16 16 1 White Fish 78 18 3 1 Salmon 77 16 5.5 1.5 Egg 74 14 10.5 1.5 Butter 15 83 3 =========================================

It will be noted that meats, cheese, and such vegetables as peas are high in proteids, while certain other vegetables, as rice and white flour, are high in starch or carbohydrates. According to the table given above, a man at moderate work requires 4.1 ounces of proteids and 17.5 ounces of carbohydrates per day. If, then, the carbohydrates were to be made up entirely from potatoes, 18 per cent of which is starch and he should need 17.5 ounces, he must have 100/18 of 17.5 or 97 ounces of potatoes per day, an amount equal to about 6 pounds. If, however, with the potatoes, he should eat half a pound of bread, of which about half is carbohydrates or 8 ounces, the amount of potato necessary would be cut down, and so on with as many combinations as one might choose to make.

It is curious, however, that when different kinds of food are available, one naturally combines different articles of food, so as to make up the well-balanced daily ration, so that the different parts may have the proper proportion. For instance, butter is always used with bread in order to add to the proteid and starch of the bread the necessary fat. With potatoes or rice, either butter or gravy or meat is always used because potatoes and rice are lacking in proteids as well as in fats which the meat supplies. Bread and cheese are well known to make up a good combination, and the table shows why: the bread furnishing the starch and the cheese the proteid and fat. Eggs alone are a very poor article of diet since no starch at all is present, and therefore it is that when eggs are eaten for breakfast, as is so generally the custom to-day, either a generous helping of cereal ought to be given with the egg or else a generous supply of bread or toast ought to be included in the breakfast. Milk is generally considered an ideal article of food, and yet it contains no starch, and it is undoubtedly because of this fact that milk and bread is more palatable as well as more nutritious than milk alone.

Human appetite.

One other factor needs to be considered in this matter of selecting one's daily food, and that is the respect which must be paid to the appetite. The most carefully balanced ration will fail to satisfy the ordinary human being unless it is served attractively and unless sufficient variety is provided. To be sure, soldiers in the army are furnished a carefully computed ration consisting of so much meat, either fresh or salt, so much bread, and so much vegetable food, and the variety being small, the soldier has to put up with his dislike to the same food day after day. The need of fresh vegetables has been proved by the results of a continuous diet of salty food on certain classes of men, such as sailors.

It is well known that a failure to provide fruit or fresh vegetables results in the disease known as scurvy, for which, practically, the only cure is a changed diet. The writer has no doubt but that in many farmhouses a very similar condition, perhaps not so pronounced, exists on account of this very lack of variety in the daily menu. He remembers to this day a week's experience in the house of a well-to-do farmer in the early spring when the winter vegetables were exhausted and before summer vegetables appeared, when the dishes offered three times a day throughout the week were salt pork in milk sauce and boiled potatoes.

Providence intended the different digestive organs of the human body to work, and there is no possibility of condensed or concentrated foods taking the place of ordinary victuals, as has been suggested. The stomach must have some bulky material on which to work, and similarly the intestine must be comfortably filled in order to exert its forward movements. It is in the same way intended that each organ shall supply the necessary digestive juices to take care of the different kinds of foods taken into the system. It is just as important that the liver should be called upon to act on a certain amount of fat as that the gastric juice should break up the molecules of the proteid, and just as important as both of these is the fact that the saliva should flow freely to decompose the starch before it enters the stomach. It is not intended, however, that the healthy individual should deliberately overload any part of the digestive system.

If a child, in a hurry to get to school, swallows bread and milk without chewing and without allowing the starch to be acted upon in the mouth, then an overburden is placed on the pancreatic gland, making that organ less capable of its regular work. And if, again, the food is drenched in fat, if everything is fried, or if butter is used in large quantities, the liver becomes overworked and cannot keep up with the demands, and digestive troubles follow.

Effect of individual habits.

Assuming that the amount and quality of food have been properly adjusted, that each of the several constituents is in proper proportion, and that a suitable variety is maintained, there are still other phases to be considered before the nourishment of the individual may be considered satisfactory. Nature has furnished man with a guide both to the quantity and quality of food that should be taken into the system,—that is, his desire for food, or his appetite,—and, in general, this guide may be safely trusted both as to the quantity and quality, although, in the latter, the appetite is not so trustworthy as that of the lower animals.

Unfortunately, the appetite is easily distracted by the general conditions of health, and when once the healthy tone of the system has been relaxed, the appetite becomes misleading. For instance, a person not indulging in muscular exercise, but sitting still all day and eating candy or other sweets, has no desire for food, and the lack of appetite in this case indicates, not a failure of the need of food, but abnormal conditions of the system. Also the conditions of housing, lack of ventilation, excessive heat, excess in the use of stimulants or of food, all affect and interfere with the guidance of a normal appetite. Some persons go to the other extreme, and, having been in their earlier years accustomed to heavy exercise and generous feeding, forget that in a more quiet life, less breaking down of the tissue occurs and therefore less food is required. Their appetite is a poor guide since it leads them to immoderate eating, resulting in time in an overloading of the organs and the probable poisoning of the system.

Cooking.

Good cooking is as important as any other part of the process of digestion, and, in fact, cooking may be said to be the first step, since there the breaking down of the food tissue occurs, whereby subsequent action by the juices of the body is made easier. For instance, beef may be cooked so long and in such a way as to dry and harden the fibers, making it almost impossible for subsequent digestion; and on the other hand, it is possible to so stew or boil or steam tough meat as to make it quite easily absorbed by the stomach. Cereals, if properly boiled at the right temperature, and for the right length of time, will have the starch granules so broken up that the saliva will act easily on the broken granules. Raw vegetables containing starch are not acted upon in the mouth and are digested afterwards only with great difficulty, while cooked vegetables are a most desirable article of diet.

A great deal is said nowadays about overeating, and Horace Fletcher affirms that the average man would be much healthier and much stronger if he ate not more than two meals and generally only one meal a day. The relation between the amount of food eaten or the amount of food absorbed or utilized and the need for food cannot be determined for the average but only for the individual. There is no doubt but that men or women doing muscular work require greater amounts of food than those not so engaged. It is a common practice to increase the amount of oats which a horse consumes when the horse has hard work to do and to cut down the amount of grain when the horse stands in the stable. It is curious that this practice, so well known to give good results, is not applied to the human animal as well. But very few men will be found voluntarily to diminish the amount of their breakfast or dinner because on that day or on the following day they are going to stay in the house instead of engaging in vigorous outdoor labor.

No discussion on foods would be complete without a repetition of the frequently given warning, against fried meats and vegetables. Frying coats the outside of the food with a layer of fat not easily penetrated by the digestive juice and not acted on in the stomach. Therefore, all fried food, unless thoroughly chewed and then only when the frying is done in very hot fat so that it remains on the outside of the whole piece, will pass through the stomach without being acted upon. Frying is a quicker process than roasting, an advantage which appeals to the American notion of haste, but it is better to begin the preparation of the meal earlier and cook the meat by roasting or stewing and the vegetables by boiling or baking rather than to postpone the preparation of the meal until ten minutes before the hour and then fry everything.

Muscular and psychic reactions.

Another factor in the power of the body to utilize the food values is the condition of the body at the time of the meal. If the individual is exhausted or even tired, no complete digestion is possible, and particularly is this true if the exercise has involved excessive perspiration. So in hot weather, a heavy meal should not be eaten until after a half hour's rest and after copious water drinking to compensate for that loss of perspiration.

Studies on the digestion of foods and on other matters pertaining thereto have shown that the smell of food, or the mere suggestion of food, stimulates the organs for the production of the digestive juices. It is directly and literally correct, therefore, to say that one's mouth waters for this or that food because the thought or anticipation of the food, if pleasant, will actually cause the saliva to form and flow in the mouth. This is true of the other digestive juices as well, so that an appetizing fritter, for instance, showing the rich, brown crust will stir up the bile, and when the fried cake reaches the opening into the intestine, the bile will be there ready to act. This has been demonstrated by putting into the stomach of sleeping dogs various kinds of foods and finding that no digestive juices whatever were produced, although with the dog awake and seeing the food before eating, the juices began to flow in the usual fashion.

It follows, then, that the enjoyment of food is quite as important as any other digestive function, and on the contrary, the eating of all sorts of foods with no interest or attention is the best way to induce subsequent indigestion. The fact, then, that a business man eating at a quick-lunch counter does not get the full enjoyment and benefit from his meal as compared with those who sit leisurely over a well-appointed table does not result altogether from the difference in the viands, but rather in the different attitude toward the meal. It would undoubtedly be a great gain in every household if more attention could be given to a cheerful intercourse at meal times—not for the better relationship which would follow, but merely for the effect on the digestion.

After meals, violent exercise is not desirable because thereby vitality is taken away from the muscles of the stomach and intestines and is used up in the other muscles; but it is vigorous exercise after heavy meals only that is condemned, since moderate exercise after ordinary meals is not objectionable. Nor is there any evidence, unless the meal has been excessive, that mental exercise after a meal does any harm. The amount of mental tissue used up in the ordinary processes of mental work is not great enough to call for any large diminution of the supply of blood to other parts of the body.

Consumption of water.

A move in the right direction to-day undoubtedly is the tendency to increase the quantity of water to drink. The body is nine-tenths per cent water, and while a large part of the water in the tissues is made chemically by combinations of hydrogen and oxygen, there must be a constant replenishing of the liquids of the body.

The ordinary person ought to drink, or consume with his food in some way, at least two quarts of water a day, and many difficulties with the liver, kidneys, and other organs would be avoided if this amount of water daily were imbibed. Probably the contention that water should not be taken at meals is not particularly tenable except as the continual swallowing of water increases the tendency to swallow food without chewing, a childish habit sure to lead to distress later. But, to eat one's dinner or part of one's dinner and then drink a glass of water cannot reasonably be assumed to interfere with any digestive process. It is quite likely, in fact, that the greater dilution of the mass in the stomach will tend to easier absorption later on.

Condiments and drinks.

There are certain kinds of foods which, though not strictly included in the four elements of food already named, yet are so common as to deserve special mention. Chief among these are the condiments and drinks, particularly coffee and tea. So far as the nutritive value of such materials as salt and pepper, vinegar or spices, goes, they are practically negligible, and yet, undoubtedly, these flavors play an important part in the suggestion of pleasure and therefore in the excitement leading to the excretion of the digestive juices. If one ate salt pork and boiled potatoes always, eating would be a tiresome affair, and it is quite likely that such a sameness of food would fail to excite subsequent digestion, merely from the monotony of the affair. Salt, however, has a particular role in that the human body craves this mineral, and, while its exact value in the body is not clearly known, a certain amount of it must always be provided. The wild tribes of Africa, for instance, away from deposits of salt consider it their most valuable possession and will go to great lengths to procure it. Animals, in the same way, go great distances for a supply of salt.

Coffee and tea are generally consumed merely for the pleasure which the warm drink gives. Both, however, have a certain stimulating effect on the nervous system, and when a tired woman refuses food but drinks cup after cup of strong tea, the exhilarating effect can be produced only at the expense of nerves and muscular tissue which must be later atoned for. Similarly, when a man under stress drinks strong black coffee to keep up, he must pay the penalty for the stimulant. The natural forces of the human body are able to do normally a certain amount of work, their ability to perform this work being directly proportioned to the energy derived from the food-supply taken into the body.

No amount of tea, coffee, or alcohol will add to the living tissue of the system; it merely goads the nerves and muscles to further action, however tired and unwilling they may be. When the stimulant is stopped, or after a time in spite of the stimulant, the exhausted nerves and muscles refuse to continue, and the depleted body stops work and may even die. A certain amount of stimulants at infrequent intervals for particular occasions may do no harm, but the pity of it is that the habit once started, the ultimate effects are forgotten in the apparent relief of the moment. In the case of tea, besides the stimulating effect, a certain substance known as tannin is developed, particularly when the tea is boiled, and this substance is really harmful on account of its strong astringent property, which acts injuriously on the membrane of the stomach. The bitter taste of the tannin is disguised when milk is used with the tea, and it has been pointed out that tea used without milk or cream is safer than tea with milk, because without the milk the bitter taste would prevent the tea being boiled so long.

Alcohol is stimulating in its nature, because of its setting free from their usual control by the will the unconscious elements of the brain; while the effect of alcohol on the system as a whole is, as has been carefully proved by scientific investigation, unfortunate in every respect. Whether the alcohol be in the form of whisky or brandy or gin or in such milder forms as wines, beers, and hard cider, the continued use of even a small quantity acts adversely on the memory, on the will, on the intellect, on the inventive power, and on all the mental processes. It has a deteriorating effect on all the muscular tissue throughout the body, and while this is sufficiently deplorable, its effect on the mind is by far the more serious. No idea is more false than that a small amount of alcohol aids in the performance of work of any sort, and experience in the army, navy, and in exploring expeditions all go to show that the use of alcohol in any form reduces the capacity, both for activity and endurance. As a protection against cold, it is worse than useless, and the feeling of warmth which drinking alcohol in any form produces, does not manufacture heat in the body, but is rather a source of danger on account of the reaction of the whole system.

Tobacco.

The use of tobacco may or may not be injurious to the human system, and it is said by those accustomed to its use that it is for them a source of great enjoyment and comfort. The essential poison of tobacco is known as nicotine, and experiments are very readily made with this substance, extracted from the plant, to show its deadly character on the heart and nerve cells of animals. It is easy to demonstrate that the use of tobacco affects the heart, since the common "out-of-breath feeling" which comes to users of tobacco when climbing hills or running is well known. No young man training for an athletic event would think of smoking, on account of the danger to his wind.

No boy should smoke, because nothing should be allowed to interfere with the fullest development of the heart and nervous system, and without question tobacco is a potent factor in influencing both. In many individual cases it has been shown that the use of tobacco in excess has a bad effect on digestion, while in other cases the trembling hand and inattentive mind indicate the result on the nervous system. No general law or rule can be laid down, and each man must act as his own individual constitution seems to require.

The drug habit.

The use of drugs is, in some cases, so persistent and leads to such dire results that it is well worth while to enter a protest against such practices. The poor creatures who have become fast victims of the morphine habit or the opium habit or the cocaine habit, or of any one of a dozen which might be named, will not be affected by anything that may be said here. But a word of warning may serve to restrain those who are only at the beginning of this downward path of which the end is positive and certain. The use of drugs once begun is sure to increase until, stupefied by their action, the victim becomes a sot, unfitted for work and a burden to himself, his relatives, and his friends.

Not less dangerous is the use of so-called patent medicines. In most cases, patent medicines are swindles, pure and simple, containing no remedial ingredients and acting only as stimulants. An advertisement some time since, which claimed to cure not only tuberculosis but also cancer, falling of the womb, hair, or eyelids, insanity, epilepsy, drunkenness, disorderly conduct, and pimples was printed in many newspapers. This remarkable remedy was found by analysis to contain ninety-nine parts of water to one part of harmless salts. Many of the vaunted remedies contain morphine or alcohol in such large quantities as to be dangerous, the more so because their presence is not suspected. Such remedies as Dr. Bull's Cough Syrup, Boschees German Sirup, Dr. King's New Discovery for Consumption, Shiloh's Consumptive Cure, Piso's Consumptive Cure, Peruna, Duffy's Malt Whisky, Warner's Safe Cure, and Paine's Celery Compound are all by analysis said to contain large amounts of morphine, chloroform, or alcohol.

Consumptives cannot be cured by any drug now known, and any person who believes it is mistaken. Cancer still baffles the skill of the most clever and the best-trained scientists. It is perfect folly to believe that any drug or man can cure either disease by a few pills or by a few bottles of medicine. The wise man or woman will avoid patent medicines unless they carry their formula on their label and unless they are prescribed by some reputable physician.



CHAPTER XIII

PERSONAL HYGIENE

Whatever the conditions under which one lives, or whatever his abstract knowledge of foods and sanitation, the health of the individual resolves itself at last into a question of his personal habits; and some of these personal questions must be considered in a book of this character.

Exercise.

One of the commonly accepted facts of hygiene is that, for the best development and for the perfect health of the human body, a certain amount of exercise should be taken by each part of the body. This is true not only for the larger muscles, such as those of the arms and legs, but also for the muscles of those internal organs less frequently considered. Experiments have been made by tying up some part of the body, such as the forearm, with the result that, in the course of a few weeks, its functions have been so lessened that its usefulness is temporarily at an end. But the general effect of exercise on the body, aside from the beneficial results on the particular muscles engaged, is to promote the building up of new lung tissue. Oxygen is received from the lungs through the blood and is carried to the different parts of the body, where it serves the useful purpose of carrying off the waste products of the different organs. If the lung action is inadequate, if deep breathing in fresh air is not practiced, or if, through laziness, no exercise is taken, then the amount of oxygen supplied will be deficient and the body will be loaded up with the toxic products resulting from decomposition. The exact effect of exercise upon the lung action may be seen from the fact that under ordinary circumstances a man breathes about 480 cubic inches of air per minute. If he is walking at the rate of 4 miles an hour, he inhales air at 5 times this rate, and if he is walking at the rate of 6 miles an hour, inspiration increases to seven times this rate, or 3360 cubic inches of air passes through his lungs per minute instead of 480, as when at rest.

Of course, it is assumed that in the country a person has no lack of exercise, and that of all men the farmer is in least need of exercise. But, as a matter of fact, the exercise which he gets is irregular and confined to certain sets of muscles, rather than to the development of the whole body. Agility, for instance, quickness of action and immediate control of the muscles, is far less common in the country than is supposed, although there is probably no lack in the actual power of the muscles. It is common observation that among farmers an erect carriage is less frequently seen than an awkward, shuffling gait. The fact is, that exercise, to be beneficial, should affect not one set of muscles, but all the muscles of the body, because the continuous exercise of one set, while leading first to growth, results later in demolition and waste. When, however all the muscles of the body are exercised, there is no demolition or waste, but a healthy growth throughout. Regular exercise is beneficial, not merely to the muscles involved, but also to the other organs of the body. Exercise sharpens the appetite, makes digestion more perfect, and increases the absorptive power of the intestinal membranes; conversely, lack of exercise, which is found in the country in the winter, lessens both the digestive power and the appetite.

Clothing.

Little need be said on this subject, since the amount of clothing needed varies so greatly with the vitality of the individual. It has already been pointed out that in rural communities the death-rate from pneumonia, bronchitis, and similar respiratory troubles is much higher than in urban communities, and it is quite possible that deficient or unsuitable clothing is practically responsible for this.

The object of clothing is twofold: to protect the body against the weather, particularly against changes in the weather, and secondly, to protect the body against injury. Included in the former are the defenses against the elements of cold, wet, and heat; while the protection against injury is chiefly a matter of shoes. As has been pointed out, a large part of the food consumed by the body is utilized in the production of heat, whereby the body temperature is maintained at about 98 degrees Fahrenheit. A large part of this heat is continually being lost from and through the skin by radiation and evaporation, and evidently some regulating influence must be provided so that the amount of heat given off may be adjusted to variations of the external temperature. To be sure, the skin itself acts as a regulator, since a rise in temperature causes the blood vessels on the surface to distend so that a larger quantity of blood is distributed over the surface and thereby more freely evaporated. Fall of temperature, on the contrary, causes a contraction of the blood vessels and therefore a reduction in the evaporation. But this is not sufficient where external temperature undergoes wide variations, as in the northern and central parts of the United States, and a modification of the clothing is a necessary supplement. The main object of clothing, then, is not to keep out cold or heat, but to preserve and make uniform the evaporation from the body. It is an agent of the same sort as food in so far as the body temperature is concerned, and without doubt light clothing requires a greater amount of food; while, on the other hand, warm clothing will make possible a lighter diet.

The best non-conductor of heat is still air, and if one could always remain in quiet air, no clothing of any sort would be necessary, even in the most severe weather, because the air itself would serve as a garment and would prevent radiation from the body. Therefore, loose, porous garments containing air in their folds and pores are much warmer than a single, tightly woven garment, and the same material made up in three or four thicknesses will give the body far more warmth than an equal weight of texture made up in a single thickness. Similarly, a tight garment is much less warm than a loose one. A practical demonstration of this fact is found in the comparative lack of warmth in an old, much-washed, quilted, bed blanket which is very heavy but quite lacking in warmth compared with a light fluffy woolen blanket, newly purchased.

Much has been written on the advantages of woolen underwear, on the ground that since clothing is intended to retain the body heat and since wool acts as a more effective non-conductor of heat than either cotton or linen, therefore the woolen undergarment is of the greatest value. Another argument urged in favor of woolen undergarments is that they check the chill resulting from excessive perspiration, since the non-conducting power of wool prevents any rapid evaporation of perspiration responsible for the lower temperatures. For this reason, woolen undergarments are always recommended for those climbing mountains or in occupations where violent exercise is likely to be followed by rest or quiet in cold air. The objection to woolen undergarments at all times is that with sensitive skins irritation may take place, and the odd saying of Josh Billings becomes pertinent, namely, that "the only thing that a wool shirt is good for is to make a man scratch and forget his other troubles." Underwear woolen only in part may take the place of all-wool garments and have the further advantage of being less expensive. The amount of clothing worn in winter depends, or should depend, on the character of the occupation of the wearer.

Formerly, heavy woolen underclothes were almost universally worn throughout the winter without regard to the employment of the individual. When an out-of-door occupation was pursued a large part of the time or when the temperature indoors was hardly above freezing, then heavy clothing was essential; but now that much time is spent in a well-heated house or office, heavy clothing is as objectionable as overheated rooms, and the comfort and health of the body will be much better preserved by not increasing the weight of clothing except when exposed to the outer air. It must be remembered, however, that old persons, whose circulation is impaired and who are forced to lead sedentary lives, will always have difficulty in maintaining the body heat unless the outer temperature is high, and for such, woolen undergarments are very useful. The outer garments in winter, to be efficient, must have two qualities, namely, an impervious surface so that winds may not penetrate and a loose open weave in which air may be held so that warmth may be secured.

Rubber boots, although very common in the country, are not desirable as a foot covering, because they do not allow the perspiration to evaporate, but rather hold the foot in a moist condition very detrimental to it. Rubber-cloth overshoes or arctics are much better than rubber boots, and felt overshoes are equally satisfactory. Chilblains are fostered by the use of rubber boots, and cloth shoes are a great relief when the feet are thus affected.

Ventilation of bedroom.

Since the agitation for fresh air has become so extensive and the knowledge of the dangers of tuberculosis so widespread, much more attention has been given to the ventilation of bedrooms, and whereas formerly the night air was religiously excluded from a sleeping room, it is not at all uncommon now for a window to be kept wide open, even through the coldest nights of winter. From what has already been said on the subject of ventilation, it is plain that to breathe over and over one's expired air is not healthy, and while it is possible that a bedroom may be so large that the concentration of the organic matter in the air may not affect an individual sleeping in the room, yet in most cases it must be admitted that the bedroom is so small or the number of people in the bedroom so large that this possibility does not exist. It is, again, possible that the structure of the house may be so poor that it is not necessary to open a window to get plenty of fresh air; the writer remembers sleeping in rooms where, with the windows shut, paths of snow across the floor in the morning showed the intimate connection between the inside and the outside of the room.

But the tendency nowadays is to build better houses, to cover the walls with paper, to put on double windows, and even to paste up the cracks to make the room as air-tight as possible. To sleep in such a room without a window open may not be committing suicide, but it is a deliberate method of reducing the vitality, of insuring a headache or a numbed and stupid mental condition, and of loading up the system with poisons which ought to be eliminated by the oxygen which fresh air supplies. It would add many years to the lives of the people of this country if, from childhood up, the habit was formed of sleeping with the window open. Nor need one fear that a cold would result from such exposure. A cheesecloth screen in the window prevents any draft and yet allows perfect ventilation. The face is trained to all kinds of exposure without any danger of catching cold, and there is no reason why, if the bed clothing be sufficient, the night air should not be thoroughly enjoyed without danger. Of course, the bed clothing must be sufficient; two lightly woven blankets are always better than one heavy one. Wool is better than cotton; if a cotton quilt is used, it should be loose and not tied tightly.

Bathing.

An important function of the skin is to expel objectionable elements coming from the breaking down of the cells and from digestive processes; the skin is quite as important a factor in getting rid of this waste matter as those other processes more commonly considered in this connection. This action goes on most energetically when the secretion of perspiration is abundant and when the temperature of the surrounding air is so high that perspiration does not evaporate as rapidly as discharged. All these secretions contain more or less solid material which, unless removed, accumulates on the surface of the skin to clog up the glands and, in some cases, to putrefy and decay. It is this decay of organic matter on the surface of the skin which causes the odors plainly noticeable in a crowd, particularly in the winter time. This accumulation can be prevented only by frequent bathing and by wearing clean clothes, and there is no surer indication of a proper self-respect than the habit of cleanliness, both as to one's person and one's clothes. There is also the very practical feature that cleanliness is an effective method of discouraging infection and disease, partly by the removal of scurf and partly by the greater healthfulness of the skin thereby induced.

Baths have always served as therapeutic agents, and evidences of their use may be found in Roman paintings and in Egyptian sculpture to-day. But from our standpoint it is their hygienic importance that is insisted upon. Ordinarily, the temperature of the bath should be between 90 and 100 degrees, and enough soap should be used to counteract the oily nature of the deposits on the skin.

Unfortunately, facilities for bathing, except in summer, have not been generally supplied to detached houses in the country. Plumbing in most houses has been lacking, but in these days bath-rooms are being installed with surprising rapidity, and the conveniences resulting are enjoyed as soon as they are understood. Only a few days ago, the writer was told of a small village of perhaps two or three hundred persons where this last summer one house, the first in the village, was provided with a bath-room, to the great interest of all the villagers. The convenience and comfort involved were immediately appreciated, and the plumber, who came in from a neighboring city twenty miles away, secured contracts for and installed twelve bath-rooms in twelve houses before he was allowed to leave the village. This same interest is everywhere noticeable, and the lack of bathing throughout the winter, formerly, alas, so common, is now giving way to a greater cleanliness, thereby improving the health and character of the inhabitants.

A great deal has been written about the value of a cold bath, particularly in the morning, and many people, from a sense of duty, suffer what is almost torture taking a shower bath or a cold plunge bath on rising. When a cold bath (which should not last more than a few seconds) is followed by a good reaction, that is, when after drying, a distinct glow is felt, there is no objection to its use, and undoubtedly it has a tonic effect for those whose vitality is able to endure the shock. But cold baths for their tonic effect are desirable only when the individual is assured of their lasting benefits. Nor must one judge of the effects by the immediate results, inasmuch as the splendid feeling which follows may be succeeded by a period of depression lasting the rest of the day; in which case, the total effect of the cold bath is bad rather than good. Baths for cleanliness are everywhere desirable, and their frequency should depend upon the individual, his constitution, habits, and work; upon the season and temperature; and on the conveniences for bathing in the house. Baths for tonic effect are not necessary, and if not a pleasure, may very properly be omitted.

One other point to be noted is that no practice is of more value in reducing the ravages of contagious diseases than a frequent and conscientious washing of one's hands. For germs are most certainly transmitted from one person to another, and it is accomplished more frequently by the hands than by any other part of the body.

The invitation, therefore, to a guest to wash his hands before dinner is really an invitation for him to disinfect himself or to get rid of the germs which he is carrying, in order that the host and his family may not be infected during the meal. The guest owes it to his host always to accept the invitation, whether he thinks he needs it or not. Doctors recognize the necessity, and it is surprising to observe how many times during the day a doctor washes his hands, even though he may not come in contact with any particularly infectious disease. An ordinary man, on the other hand, washes his hands only when he thinks they are dirty, although his daily occupation may expose the skin of his hands to infection many times worse than that which the doctor experiences.

Mouth breathing.

Children have sometimes wondered why they were made with both mouths and noses, since they could breathe equally with either, and many years have gone by before they realized that breathing through the mouth was not intended, but that the exclusive province of the nose was to furnish air to the lungs. The reason for nose breathing rather than mouth breathing is twofold. In the first place, no provision for removing or filtering out germs from the air is made in the mouth, whereas in the nose the crooked passages, the moist surfaces, and the hairlike growths all tend to strain out any germs normally in the inspired air.

Further, breathing through the mouth has a tendency to induce inflammation in the tonsils and in the air passage connecting with the ear. This inflammation develops into those growths known as adenoids, which, when enlarged sufficiently, close the nostril entirely and prevent its normal use. A recent examination made by the New York Board of Health of 150 school children, all in some way abnormal, showed that 137 had either adenoids or enlarged tonsils. Example after example could be given of school boys and girls whose mental and moral development has been markedly retarded because of mouth breathing. One need only look at a child or adult who constantly keeps his or her mouth open to be impressed by the listless, vacant, inert appearance of the face thus disfigured. Figure 74 shows a photograph of a schoolgirl just before an operation and the characteristic expression due to adenoids is plainly marked. Earache is largely due to adenoids or to inflammation that rapidly leads to adenoids, and Mr. William H. Allen, Secretary of the Bureau of the New York Municipal Research, reports that in 415 villages of New York State, 12 per cent of the children living there were found to be mouth breathers. Whenever a child is unable to breathe through his nose, is slow in talking, and then speaks with a stuffy accent, calls "nose" "dose," has a narrow upper jaw, and is either deaf or has inflamed eyes, it is practically certain that enlarged tonsils and a well-developed growth of adenoids are present and should be removed. Not merely do these growths interfere with the mental and physical development of the child, but they also make him more susceptible to contagious diseases, particularly those of the lungs and bronchial tubes.



The removal of adenoids is a simple operation, lasting not over a minute, and the result of the operation is in some cases almost miraculous. The medical inspectors of the New York City schools consider the removal of adenoids as a most important part of their work, and groups of children are regularly taken from the schools by the principal to the clinic at the hospital, where one after another tonsils are cut off or adenoids are removed, all fright and commotion being avoided by the gift of five cents as a reward.

Eyes.

Another evidence of advancing knowledge in matters pertaining to sanitary hygiene is shown in the greater attention given to the eyes, particularly of children. Such incidental troubles as headache, sleeplessness, or biliousness are frequently due to weak or strained eyes, and in the case of school children a great deal of the alleged insubordination, backwardness, and truancy of the children is caused by their being unable to see written instructions or explanations.

It is not likely that this increased difficulty with the eyes is a new thing, but rather that both physicians and laymen are more careful as well as more expert in diagnosing the trouble. The New York State Board of Health in the fall of 1907 sent out cards for testing the eyes of school children to 446 incorporated towns. The results of using these cards in 415 schools were returned and showed clearly that nearly half the children of school age in the state had optical defects. A similar test in Massachusetts recently discovered 22 per cent of the school children with defective vision, and this knowledge in itself is an advance inasmuch as it suggests to each individual or to all parents that deficient vision is common and that good eyesight is not a thing to be assumed.

In the country it is more difficult, perhaps, to realize these deficiencies, because the constant outdoor life acts as an offset to the strain during the time when close work is required, and perhaps the distance from a competent oculist serves to postpone the time of consultation, but no greater folly can be indulged in than to suffer inflamed eyes, persistent headache, and imperfect vision, if it is possible in any way to secure the services of an oculist.

Never is it worth while to buy from a jeweler, a grocer, or a hardware store a pair of spectacles, much less to buy them from an itinerant peddler, since an oculist, with his particular apparatus, can measure the seeing ability of each eye and fit each eye with the necessary lens to restore normal vision. It is better to have no glasses than to have glasses that are wrong.

Teeth.

A curious result of the recent studies among school children with defective eyes and ears has been the discovery that bad teeth were quite as important in their relation to general health as either bad eyes or ears. One eye specialist went so far as to say that the teeth of school children should be attended to first, because thus many of the eye troubles would disappear.

As has already been pointed out, the first, step in digestion is taken in the mouth, and careful chewing is not less important than the other parts of the digestive process. If one's teeth are not adapted to chewing, if they are bunched, crowded, loose, or isolated, the appearance of the teeth is the least objectionable feature. The real importance comes from the fact that with such teeth perfect mastication is impossible. The teeth themselves harbor germs which actually infect the food and favor its putrefaction. With decayed teeth, infectious diseases find a ready entrance to the lungs, nostrils, stomach, glands, ears, nose, and membranes. At every act of swallowing, germs are carried into the stomach. Mouth breathers cannot get one breath of uncontaminated air, and dental clinics, organized and conducted in the interests of the health of school children, have been altogether too little inaugurated. The use of a toothbrush should be encouraged in children as soon as they are four years old, and its habitual use twice a day is most desirable for every one.

Only regular examination by the dentist can keep the teeth in good condition, and periodic visits at least once a year to a dentist's office, not to the kind advertised by Indians where they are willing to extract teeth without pain, free, but where a regularly qualified dentist practices, should be the habit. Armenian children, who prize and covet beautiful teeth, are taught to clean their teeth always after eating, if only an apple or a piece of bread between meals, and while probably our American customs would hardly make this possible, there is no question but that a persistent and frequent use of the toothbrush will help much in reducing dentist bills.

Sleep.

From many standpoints sleep is the most wonderful attribute of the human body. Our familiarity, from our earliest years, with sleep, closes our eyes to its strange, its awful power. We know that every human being, once in twenty-four hours, will normally close his eyes and for a certain length of time be as oblivious to things present as if already in the sleep of death. It is a common belief that sleep is nature's provision for restoring tired muscles and jaded nerves, and for building up new tissue in cell and corpuscle. Excessive exertion produces a numbness and exhaustion so that the body becomes "dead tired," and sleep brings back life and elasticity. And yet some parts of the body, some muscles and some organs, do not stop work during sleep, and apparently feel no bad results for their continuous lifelong exertion. Thus, the lungs, whose muscular action is estimated at the rate of one thirtieth of a horse power, have no rest day or night, seemingly without weariness. Similarly, the heart is continually forcing blood under a pressure of about three pounds through the arteries without cessation from birth to death.

Why do the muscles of the arm and leg tire and need sleep as a restorer, while those of the heart and lungs are independent of sleep? Dr. W. H. Thomson, in his book on "Brain and Personality," finds an answer to this question in the fact that the latter do their work independently of the human consciousness, while the former are stimulated and directed by the will. He points out that fatigue comes in proportion to the intensity of the mental effort expended. A baby, to whom everything is strange, whose consciousness is absolutely zero at birth, however well developed his body, sleeps five sixths of the time because of the mental efforts needed in his simplest bodily acts. Brain work, the most absorbing task of consciousness, is always the most compelling in the matter of sleep. Not the muscles themselves but the attention, the skill, the mental effort required to direct those muscles, Dr. Thomson says, constitute the reason for sleep, a reason which, to those who labor only with their hands, must seem unutterably sad. He says that while muscle work is the commonest and the simplest, so it is also the most poorly paid and the most degrading, and that while brain work is ennobling and the highest type of labor, it is so difficult of attainment and produced only by such grievous toil that most of us shirk it, even while reproaching ourselves at our lack of capacity and purpose. The pathetic burden of unfulfilled possibilities, he says, is the curse of labor, and only in sleep does man have temporary oblivion through which, for a time, he forgets his work and, as it were, uses sleep as an anaesthetic for the pain of labor, to rise therefrom each morning ready to carry his burdens for another day.

Lack of sleep, to those whose brains are active, speedily brings nervous disaster, and the consciousness, from being the active superintendent of the body, becomes inert, and the body drifts like a boat without a pilot. Lack of sleep to those whose work is muscular means a numbness in the nerve cells which guide those muscles, so that they disobey the will or act unreasonably and without direction. But too much sleep, like over-indulgence in any anaesthetic, is only shirking that duty and avoiding that effort to which the higher life calls us, and the sluggard who sleeps more than the tired nerves need is allowing himself to sink deeper and deeper into a slough of despond. He forgets his toil in sleep, but it is only by active, conscious effort when awake that his work may be lifted to the higher plane where the brain is active, where work ceases to be mechanical and a burden, and where that greatest reward of personal satisfaction can be obtained.



CHAPTER XIV

THEORIES OF DISEASE

Disease may be defined as an abnormal condition of the human body, and since there is no one condition of the human body which can be satisfactorily described as normal, there is, therefore, no exact definition of disease.

What is disease for one person because of a departure from his normal health might not be recognized as disease in another person of different normal vitality. Nor is it possible to assign any particular and special cause for disease since the condition recognized as disease is the result, usually, not of one but of a series of causes or circumstances more or less connected and linked together, and in many cases not obviously associated with the resulting disease. Thus, in records of death, it is very common to see reported pneumonia as the cause underlying and fundamental, when the cause was really typhoid fever, the patient yielding to the former disease because of the enfeebled condition due to the latter. Again, many children contract diseases like measles or whooping cough because of reduced vitality due to insufficient nourishment, lack of clothing, and neglect, and their illness is said to be due to measles or whooping cough when under proper conditions of care and attention they would not have the disease at all. The causes of disease therefore may be divided into two classes, direct and indirect. In the latter class are to be included such causes as environment, heredity, age, and occupation. In the former class are to be found such causes as the introduction of disease germs into the system; the action of poisons, whether introduced into the alimentary canal or into the lungs, and such external conditions as excessive heat and cold and accident.

Effects of dirt.

At one time it was thought that diseases could spring up in the midst of dirt, and one of the strong arguments for keeping houses clean, for removing manure piles, and cleaning up back yards, was the fear that without such care diseases might be induced in those living near by. This is possible in a certain sense, but unless the seed or germ of the disease is present in a pile of dirt there need be no fear of the disease being developed. There is, however, a probability that by the organic decay and the consequent pollution of the atmosphere the vitality, energy, and resistance of the individual in the vicinity may be weakened.

It is well known, for instance, that prisoners confined in damp dark cells lose vitality, and when released, have but little of their former physical strength. In the chapter on Ventilation, it has been shown that persons confined in a small room and breathing their own exhaled air may in time become unconscious and die, and therefore it is reasonable to believe that persons living in the immediate vicinity of decaying animal or vegetable matter will suffer a loss of vitality and will have less resistance to disease.

Blood resistance.

It is well known that there are present in the body certain agencies which act as guardians of the body against disease; that there are certain corpuscles of the blood and certain liquids circulating through the system which immediately attack and if in sufficient numbers or strength drive out the advancing enemy, so that "taking a disease" in most cases means that the activity of these resisting organisms is not forceful enough to successfully combat the germs of the disease. These agencies, whether circulating liquids or cells or corpuscles, are most active in the healthy body, and anything that tends to reduce the general health, such as exposure, overexertion, imperfect nourishment, overeating or overdrinking, or lack of sleep, tends to diminish their activity and so makes the individual more susceptible to disease.

Cell disintegration.

Although disease is caused by the attacks of germs, another and far more important cause of disease is the breaking down or overstimulation of some particular organ. This is very plainly seen in diseases involving the stomach or intestines, where habitual excesses in eating lead, sooner or later, to consequent inflammation, disease, and death. This is also true of the lungs; merely living in an atmosphere full of dust will irritate the lungs to such a degree as to cause inflammation. Cancer is presumably the result of local inflammation, although the cause of the original suppuration is unknown. Similarly, appendicitis starts from some irritating cause, resulting in inflammation and the formation of pus. In very many cases the cell-disintegration seems to be a matter of heredity.

Heredity.

Heredity, the second of the indirect causes of disease seems to be assuming less importance as it is more studied. Probably in but few cases is heredity more than a chance factor in the causation of disease. Heredity, formerly considered to be the most important cause of consumption, is now understood to have little to do with this widespread epidemic, although it is agreed that children brought up in the family with a consumptive mother and father are more likely to contract the disease than if they were segregated.

It is a providential arrangement that children inherit the tendencies of both father and mother, and that the good qualities of one parent are known to offset the bad qualities of the other; probably for this very important physiological reason marriage between near relatives, where both parents would be inclined to the same weaknesses, has always been proscribed. However, even with the characteristics of the father offsetting peculiarities of the mother, it is possible for the traits of a parent to be reproduced in children, and this applies to mental traits as well as to physical. In some families there exist tendencies toward nervous diseases, such as epilepsy and insanity, although it is not accurate to say that either disease is naturally inherited. It has been observed that a tendency to cancer, to scrofula, and to rheumatism runs in certain families, but this is hardly more than saying that in certain families, where the predisposition in this direction by one parent is not offset by the tendencies of the other parent, the physical condition of the child is such as to encourage the development of diseases.

Age and sex.

As indirect causes of disease, age and sex cannot be overlooked. It is well known, for instance, that certain diseases belong essentially to childhood, measles and scarlet fever being markedly prevalent among children under ten years of age. In fact, it has been said by experts that if measles could be kept from children under five years old, the disease would be practically stamped out, since beyond that age they are less susceptible and the course of the disease is much milder. No greater mistake can be made than in exposing children to so-called "children's diseases" because of a desire "to have it over with." Not only is such exposure foolish, since it is quite possible to escape the disease altogether if in the first few years of life it is avoided, but also inviting death, since the mortality of the disease becomes markedly less and less as the age of the patient advances.

Many of the diseases of children are due to imperfect and incomplete development; either the lungs or the stomach or some other organ is not equal to its work, and the child remains an invalid or dies. Many children die from imperfect nutrition, especially in the second summer, when teething is at its height, on account of the ignorance of the mother and on account of unsanitary surroundings. No movement is more promising in the way of prolonging the lives of children than that recently inaugurated in New York which undertakes to teach mothers, of foreign nationality in particular, how to dress, bathe, feed, and bring up their children.

Another reason why disease occurs more frequently among children is, as will be seen later, that one attack of a disease frequently confers immunity upon the patient, so that, for example, a child having scarlet fever is not likely to have the disease later on in life; but this is no argument for exposing one's self to contagion, since it is quite possible that even the first attack may be avoided. Tuberculosis or consumption is preeminently a disease of youth, as is also typhoid fever. It is very rare for the latter disease to appear in children or in adults over forty-five, and for the former to develop until maturity.

In old age, diseases occur due to the gradual failure of the different organs to perform their normal functions. Some of these diseases are connected with the heart and the circulation, others with the liver or with the mucous membranes, so that among those advanced in life, rheumatism, gout, cancer, and diseases of the kidneys are very apt to occur.

One of the objects of sanitation is to eliminate disease due to bacteria and to prolong the normal life, so far as is possible, past the early period when diseases are easily contracted. It is not hoped that death can in any case be prevented, but hygiene will have done its utmost when death occurs only among the aged and when the diseases then causing death are only those which are consequent upon the wearing out of the body.

So far as sex is concerned, the ordinary rules of hygiene or the violation of those rules seem to have but little concern. It is generally understood that males are on the average shorter-lived, by a few months, than females, and all statistics support this position. Some diseases, like typhoid fever, attack males more than females in the ratio of three to two, while cancer attacks females to a greater extent than males at about the same ratio reversed. Generally speaking, however, excepting in so far as their occupations and manners of living make different their vital resistance, the principles of hygiene are not affected by the incident of sex.

Occupation.

Inasmuch as this discussion is a part of rural hygiene and is assumed to apply to only one occupation, namely, that of cultivating the soil, or of raising stock, it may not be considered pertinent to discuss the effect of occupation on disease. It is worth while pointing out, however, that occupation is a very important factor as an indirect cause of disease, and that one's chances of life are vastly greater in the open country surrounded by hygienic conditions than in a city in crowded quarters, confined for long hours each day at some unhealthy occupation.

As a general warning, it may be stated that a factory containing a dust-laden atmosphere is most undesirable, and this is particularly so when the dust is mineral dust. In the country, the only comparison of conditions possible is between that of the outdoor worker and that of the indoor worker; enough has already been said upon the value of fresh air and its improving effect on the vital resistance to make further repetition unnecessary. Unfortunately, in the past the occupation known under the general term of farming has not made itself conspicuous in statistics for healthfulness; but this has been undoubtedly due not to the lack of the value of the outdoor part of the farmer's life, but to the monotony of the work and to the very bad conditions found indoors, particularly in the winter. When this indoor life has been modified so that plenty of fresh air is supplied day and night, and when reasonable attention is paid to the demands of the body in the matter of food and drink, then the duration of life of farmers will rank high in comparison with other occupations.

Direct causes of disease.

The direct causes of disease may be due to the introduction into the human body of a specific microoerganism which, if not met by the antagonistic agencies, finally pervades the whole system with its progeny or its virus. The microoerganisms thus responsible for disease are commonly divided into two classes, namely, parasites and bacteria. In the first group are included those parasites that cause tapeworm, malaria, trichinosis, and hookworm; in the second group those bacteria that cause typhoid fever, cholera, erysipelas, diphtheria, and probably smallpox, measles, scarlet fever, chicken pox, and a number of others presumably similar.

Parasites as causes of disease.

The introduction of worms into the body must come either from impure drinking water, from impure food, or from the bites or stings of insects. When introduced into the body, those parasites that are inimical to man and produce abnormal conditions interfering with usual physiological functions may or may not develop further. In some cases, as in malaria, the very act of hatching the malarial brood is sufficient to throw the host on whom the brood will feed into a violent chill.

In other cases, as with the hookworm, while eggs are produced in the human body, they have no directly detrimental effect, the objectionable feature of their residence being due to the fact that the continual draught which they make upon the blood vessels of the intestine reduces the vitality, causing anaemia.

In other cases, as with the guinea worm, found in Africa and South America, the worm wanders from the stomach, which it enters toward the surface of the body, and finally breaks through, causing ulcers or abscesses.

In still other cases, as with that form of filaria which causes elephantiasis, the adult worm or the embryos are present in the lymphatics in such numbers as to interfere with circulation, causing the fearful swellings characteristic of the disease named.

Finally, in such cases as trichinosis and tapeworm, there is usually but little inconvenience to the human being harboring them, except when their number becomes very large. Then there may be diarrhoea, loss of appetite, and other digestive disturbances. The different tapeworms are generally responsible for nothing more than indigestion and nervousness. These latter parasites are, however, formidable in so far as their size is concerned. The mature pork tapeworm is about ten feet long, although the eggs, seen in the pork flesh, giving it its name of "measly," are only about a thousandth of an inch in diameter. The fish tapeworm, when mature, measures about twenty-five feet in length, while the beef tapeworm is about the same length. These worms can develop only in the bodies of the animals named, and find their way into the human body only through the medium of imperfectly cooked meat.

If proper precautions be taken in these directions, if only water is used for drinking which is known to be free from such parasites and their eggs, and if insects like mosquitoes and fleas are kept away by screening windows and doors, and if meat be always thoroughly cooked, the dangers of diseases from parasites will be reduced to a minimum.

Bacterial agencies.

By far the most important of the living agencies concerned with the direct production of disease are those small vegetable organisms known as bacteria. Not all bacteria, by any means, produce disease; in fact, it is not too much to say that the majority of bacteria are benefactors to the human race. Their chief agency is not to cause disease, but to prevent it, and they do this because they are able to transform the waste products of animal life, which would normally be dangerous to health, into harmless mineral residue. They are really the scavengers of the earth's surface, not actually carrying off garbage, but rather transforming it, and, in the process, not merely destroying it, but changing it so as to make it available for plant-food. It is through the agency of bacteria that the air, which is being continually overloaded with carbonic acid from the lungs of animals, is reduced and taken up by plants so that an equilibrium is maintained. Otherwise, the atmosphere would be more and more vitiated with carbonic acid and organic vapors, and every one would die as if shut up in an air-tight room. But, because of bacteria, neither is the surface of the earth overloaded with waste organic matter nor do streams, however much polluted, continue to flow without some improvement being traced in their quality.

In some of the ordinary manufacturing processes, bacteria are all-important, as in making vinegar, wines, cheese; in fact, in any of the fermented food products. In agriculture, they are entirely responsible for supplying an adequate amount of food material to growing plants. Fresh manure is not suitable for plant-food and would be of no value on the fields or in the garden except as improved and modified by bacterial action. One of the greatest discoveries of their importance recently made has to do with the way in which peas and beans are able to absorb nitrogen from the air through the agency of bacteria. One knows that plowing under a crop of peas or clover enriches the soil, and that peas or clover make the best growth for this purpose. The reason is that these plants, through the activity of bacteria, are able to absorb nitrogen from the air and afterwards to convert it into food material.

But with all these good qualities a few bacteria, gone bad, perhaps, are associated with diseases, and by a series of experiments, chiefly those of a Frenchman named Pasteur and of a German named Koch, and of their followers, it has been ascertained that certain bacteria, and those only, will cause certain diseases. These diseases, that is, these caused by bacteria, are generally spoken of as epidemic or contagious, of which typhoid fever and cholera are examples.

All contagious diseases cannot at present be definitely associated with bacteria, probably for the reason that the methods employed to find the bacteria have not been adequate. For instance, the bacteria of smallpox has never been found, although the disease is so characteristically one of bacterial origin that no one can doubt the cause. Similarly, the bacteria responsible for measles, scarletina, and whooping cough have never been discovered, although the cause of each is also presumably bacterial. More definite information on the subject of the individual and responsible bacteria will be given in the subsequent chapters dealing with specific diseases. Inquiries into the method of growth and into the life history of specific bacteria serve our present purpose only as they teach methods for the prevention of the disease. For example; when it was found that the parasite of yellow fever, in the course of its life, spent fourteen days in the mosquito's body in such a condition that the mosquito during that time was harmless, it made possible exposure to mosquitoes laden with yellow fever for a period of thirteen days from the time of the preceding case.

Antitoxins.

But the methods of combating the different diseases when once contracted in the human body, based on the knowledge obtained of the life history of these germs, have been the most important result of their biological study. A large part of this knowledge has been acquired by the study of animals which have been found susceptible and so available for experimental investigation, and it may be that the impossibility of studying measles, for instance, in animals, may be one reason why the germ has never been discovered.

There is no evidence that animals suffer spontaneously from such diseases as typhoid fever, Asiatic cholera, leprosy, yellow fever, smallpox, measles, and so on; but it seems that in animals, as in man, the disease is the direct result of the life and growth in the animal of the characteristic disease-producing germ. The fact that diphtheria or tuberculosis can be experimentally given to rabbits or guinea pigs is without doubt the chief source of our knowledge of those diseases, although, in general, it is impossible to produce diseases in any animal which will be, clinically, precisely like the disease as it appears in man. The converse of this is also true, namely, that when it has been found impossible to experimentally inoculate an animal with a disease supposed to be bacterial in nature, then but very little of that disease is known.

The most important result of bacterial studies has been the production of what are known as antitoxins, and no more wonderful discovery has ever been made. To understand as best we may the principle involved, it is necessary to explain the process of bacterial attack. When bacteria capable of producing disease are introduced into the system, either through the mouth or into the lungs or into the blood through some skin abrasion, the bacteria, finding there a congenial habitat, thrive, grow, and multiply. In some cases, this bacterial growth results only in breaking down the cell tissues at the point or in the vicinity of the place where growth occurs; for instance, if a cut is made with a dirty knife, that is, one carrying bacteria on the blade, and is not immediately washed out with an antiseptic solution, bacteria will grow and pus will form in the cut. Similarly, a splinter, if not removed and cleansed, will produce a pus-forming wound. But unless a very extensive suppuration starts, the difficulty is all local. So it is with consumption, when the bacteria are localized in the lungs and by their growth destroy the lung tissue without, at least for many weeks, affecting the general health.