Thought Questions. The Digestive Organs.—1. In which of the digestive organs is only one kind of secretion furnished by glands? 2. In which organ are three kinds of secretions furnished by glands? 3. Which class of food goes through the lymphatics? 4. Which classes of foods go through the liver? 5. Which classes of foods are digested in only one organ? 6. Which classes of foods are digested in two organs? 7. Which division of the food tube is longest? Broadest? Least active? Most active? 8. Soup is absorbed quickly; why does eating it at the beginning of a meal tend to prevent overeating?

The Power of Adaptation of the Digestive Organs.—Of course some habits of eating are better for the health than others, yet the undesirable ways often bring so little injury that they are not discontinued. This shows that the food tube has great powers of adaptation to different conditions. But there are limits to this adaptation; there is an old saying that what is one man’s meat is another man’s poison. A brain worker cannot follow the same diet as a field hand without working at a disadvantage. An irritable stomach may be injured by coarse food that would furnish only a healthful stimulus to a less sensitive one. A business man who has little leisure at noon should take the heaviest meal after business hours. In general, it may be said that it does not make so much difference what is eaten as how it is eaten, and how much is eaten. There is a common tendency to exaggerate the importance of dietetics.

Thought Questions. Indigestion.—I. A Fetid Breath. 1. Name three causes of bad breath. 2. Let us investigate whether indigestion could cause a bad breath. In what kind (two qualities) of weather does meat spoil the quickest? 3. Suppose that meat or other food is put into a stomach with its gastric glands exhausted and its muscular walls tired out, what will be the rate of digestion, and what might happen to the food? 4. Odorous contents of the stomach (e.g. onion) can be taken by the blood to the lungs where it will taint the breath.

After answering the above questions, write in a few words how indigestion may cause a bad breath.

II. A Coated or Foul Tongue. 1. When the doctor visits you, at what does he first look? 2. What sometimes forms on old bread? (p. 158.) 3. Do you think such a growth possible on undigested bread in the stomach? 4. The microscope shows the coating on the bread to be a growth of mold. If it forms on the walls of the stomach, it may extend to what?

III. Stomach Ache. 1. How can you tell whether fruit preserved in a sealed glass jar is fermenting? 2. What connection is there between belching after eating too freely of sweet or starchy food, and the observation above? 3. A muscle gives pain when it is stretched. Why does belching sometimes give relief to an uneasy stomach? 4. Can you, by using these facts, explain a cause of stomach ache?

For what Kind of Man were the Human Digestive Organs created?—That food is best to which the food tube has been longest accustomed. It would be of the greatest value as a guide to diet if we knew the food eaten by early man during the many ages when he led a wild life in the open air. The organs of early man were doubtless perfectly adapted to the life he led. The food tube is adapted to the needs of those long ages, for a few centuries of civilization cannot change the nature of the digestive organs; yet some people disregard natural appetites and try to force the digestive organs to undergo greater changes in a few months than centuries could bring about.

To test whether an Article of Food belonged to Man’s Original Diet.—Scientists agree that the human race began in a warm country; that early man was without gristmills, stoves, or fire, and ate his food raw. If an article of food is pleasant to the taste in its raw, pure state, there is little doubt that it, or a similar food, was eaten by primitive man before he knew the use of fire in preparing his food. Apply this test to the following foods, underlining those foods that pass the test: apples, bananas, lettuce, turnip greens, turnips, fruits, nuts, beef, fowls, eggs, oysters, green corn, cabbage, pork, watermelons, grains, crabs, fish, white or Irish potatoes, yams, tomatoes.

The Order in which Man increased his Bill of Fare.—Flesh-eating animals have a short food tube, as their food is digested quickly; they have long, pointed teeth for tearing, sharp claws for holding, and a rough tongue for rasping meat from the bones. Man’s even teeth, long food tube, soft and smooth tongue, and flattened nails, indicate that he is suited for a diet largely vegetable (see Table, p. 111). The race at first probably ate tree fruits,[8] both nuts and fleshy fruits (Fig. 101). Because of famine, or after migration to colder climates, and after learning the use of fire, the race probably began to use flesh for food. Afterward the hunters became farmers and learned to cultivate grain, which formed a most important addition to the food supply, and made possible a dense population. Coarse, woody foods, like the leaves and stems of herbs, were probably added last of all. Woody fiber (cellulose) can be digested by cattle, but it cannot be digested by man.

The Natural Guide in Eating is Taste. Man should preserve his taste uncorrupted as, next to his conscience, his wisest counselor and friend. It has been developed and transmitted through countless ages as a precious heritage. Simple food is more delicious to people with natural tastes than the most artificial concoctions are to those with perverted taste.

Milk of cows is improperly called a perfect food by some writers. Although it contains the four classes of food stuffs, the proteid is in excess, the fuel food being deficient. Buttermilk is more digestible than sweet milk. Buttermilk and sugar form a valuable food for infants. Skimmed milk still contains the proteid, the most nutritious part of the milk. Sour milk, or “clabber,” and curds pressed into “cottage cheese” are more digestible than sweet milk. Cream is more easily digested than butter, which is a solid fat. Cheese is a very concentrated proteid food, and should be eaten sparingly. Eggs are a valuable food. Is there more proteid or fat in eggs? (See Table.) Pork and veal are the most indigestible of meats. Fish is nearly as nutritious as meat. There used to be a supposition that fish nourished the brain because it contains phosphates; but there are more phosphates in meat than in fish, and more in grains than in meat.

Grains contain considerable proteid (gluten), but they especially abound in starch. Wheat flour contains more gluten than corn meal, hence it is more sticky, and retains the bubbles of gas so that the dough rises well in bread making. Eggs are sometimes added to corn meal to make it sticky and cause it to rise well. Which grain has the largest percentage of oil? (See Table.) Of starch? Of gluten? Which is poorest in gluten? Grains may be made to resemble fruit by long cooking at a high temperature (300° Fahr.), for their starch is thus changed to dextrin, a substance resembling sugar. You learned that the starch of fruit is turned into sugar as the sun ripens it. Dextrin is yellow and gives the dark color to toasted bread. It is changed to sugar almost instantly when brought in contact with saliva. It is used as a paste on postage stamps.

Vegetables contain much water and woody fiber. White potatoes are underground stems and are one fifth starch. Yams, or sweet potatoes, resemble roots, and contain both starch and sugar. Beans and peas are very nutritious. They have been called “the lean meat of the vegetable kingdom.” They require boiling for several hours. If the skins are removed by pressing them through a colander, they are very easy of digestion. This purée of beans makes delicious soup. “Hull-less beans” and “split peas” are also sold by grocers.

Practical Questions.—1. Clothing and shelter for man or beast economize what kind of food? 2. Why should bread remain longer in the mouth than meat? 3. In snowballing, what is the appearance of the hands when they itch from cold? Extreme cold irritates and congests the stomach more quickly than it does the hands. Why is it that ice water does not satisfy the thirst, but often produces a craving to drink more water? 4. Should biscuits having a yellow tint or dark spots due to soda be eaten or thrown away? 5. Why, during an epidemic, are those who have used alcohol as a beverage usually the first to be attacked? 6. Do you buy more wood (cellulose) when you buy beans or when you buy nuts? (p. 95.) 7. Do you buy more water when you buy bread or when you buy meat? 8. Why do people who live in overheated rooms often have poor appetites? (p. 90.) 9. Explain how the stomach may be weakened by the eating of predigested foods. 10. Why are deep breathing and exercises that strengthen weak abdominal walls better for the liver than are drugs? (See p. 58.) 11. Sixty students at the University of Missouri found by doing without supper that their power to work was greater, their health better, and many of them gained in weight. So they ate only two meals thereafter. If sixty plowboys tried the experiment, would the result probably have been the same? 12. If a person began to eat less at each meal, or only ate one meal a day, yet gained in weight, should he agree with a friend who told him he was starving himself? Should he agree if, instead of gaining, he lost weight? 13. Why is half-raw or soggy bread harder to digest than the raw grain itself? Which would be thoroughly chewed and cause a great flow of saliva? 14. Ask a fat person whether he drinks much water. A lean person. 15. Why is one whose waist measures more than his chest a bad life insurance risk? 16. What changes in habits tend to make a rheumatic middle-aged person more youthful? 17. How is the ingenious “fireless cooker” constructed?

Definition of Food.—A food is anything which, after being absorbed by the body, nourishes the body without injuring it. Does alcohol or tobacco come within this definition?

Advantages of Good Cooking.—Taste and flavor may be developed; parasites are killed; taste may be improved by combining foods; starch grains are burst and the food softened. Thus digestion is aided.

Disadvantages of Bad Cooking.—Proteid foods are hardened; flavors may be driven off; too many kinds of food may be mixed; cooked vegetables are more likely to ferment than raw vegetables; palatable food may be made tasteless or soggy or greasy; soda and other indigestible ingredients may be added; food may be so highly seasoned as to cause catarrh of the stomach; it may so stimulate the appetite that so much is eaten as to overload the stomach. Food may be made so soft that it cannot be chewed and is eaten too rapidly; for instance, bread shortened with much grease.

The Five Modes of Cooking.—Food may be cooked (1) by heat radiating from glowing coals or a flame, as in broiling; (2) by hot air, as baking in a hot oven; (3) by boiling in hot water or grease, as frying; (4) by hot water, not boiling, as in stewing; (5) by steaming.

Radiant Heat.—Toasting bread and broiling meat are examples. The meat should be turned over every ten seconds to send its juices back and forth, thus preventing their escape, and broiling the meat in the heat of its own juices. Roasting is an example of this method combined with the second method. The fire should be hot at first in order to sear the outside of the meat and prevent the escape of its juices. If the piece roasted is small, the hot fire may be kept up; but if it is large, a longer time is required, and the fire should be decreased, otherwise the outside will be scorched before the central part becomes heated. White, or Irish, potatoes roasted with their skins on best retain their flavor as well as valuable mineral salts (potash, etc.).

Cooking by hot air can only be used with moist foods. Baking is an example. Foods only slightly moist are made hard, dry, and unpalatable if cooked by this method.

Cooking by Boiling.—To boil potatoes so as to make them mealy instead of soggy, the water should be boiling when they are put in, and after they are cooked the water should be poured off and the pot set on the back of the stove for the potatoes to dry. Boiling onions drives off the acrid, irritating oil. Rapid boiling of vegetables gives less time for the water to dissolve out the nutrients. (See Steaming.) Raw cabbage is treated by the stomach as a foreign substance, and sent promptly to the intestine; cabbage boiled with fat may remain in the stomach for five hours. Instead, it should be boiled in clear water for twenty minutes. Beans and peas require several hours’ boiling.

Cooking in hot liquid below the boiling point is better than boiling. In frying meat, it should be put in hot grease that a crust may be formed to prevent the grease from soaking in. Grease much above boiling point becomes decomposed into fatty acids and other indigestible products. Hence butter is more digestible than cooked fats. In whatever way meat is cooked, it should never be salted until the cooking is finished or the salt will draw out the juices which flavor it. Eggs may be cooked by placing them in boiling water and setting the kettle off the stove at once to cool. A finely minced hard-boiled egg is as digestible as a soft-boiled egg. Since boiling for more than a very few minutes coagulates and hardens albumin, there is no such thing as boiling meat without making it tough and leathery throughout. It may be stewed, a process which belongs to the next method.

In stewing meat, it may be plunged into boiling water for a few minutes; this coagulates the albumin on the surface. The fire should then be reduced, or the vessel set on the cooler part of the stove, or a metal plate should be placed beneath it, that the water may barely simmer. The water should show a temperature of 185° or 190° if tested with a thermometer. A piece of meat cooked in this way is tender and juicy.

Cooking by steam requires a double vessel or a vessel with a perforated second bottom above the water, through which the steam may rise to the food that is to be steamed. Steamed vegetables have a better flavor and are more nutritious than those cooked in any other way. A steamer is different from a double boiler. Oatmeal should be cooked for at least forty minutes, and it is more digestible if steamed for several hours until it is a jelly. To do this, it may be cooked during the preparation of two meals. Cooking that leaves it lumpy and sticky is a disadvantage, and makes it more likely to ferment than if eaten raw.

Thought Questions. Cooking.—Meat. 1. In making soup, why should the meat be put in while the water is cold? 2. In roasting meat, why should the oven be hot at first, and more moderate afterward? How should you regulate the temperature in boiling or stewing meat? 3. What happens to salt or anything salty on a cloudy, damp day? This is because the salt attracts ____. This shows that meat should not be salted until after it has been cooked, because if salted before ____. 4. Very tough meat should be b__ed or st__ed. 5. Meat may be prevented from becoming grease-soaked when frying by having the grease very ____, use very ____, simply greasing the ____.

6. Bread. Bread crust causes the ____ to be used more and cleans them. It will not ____ together in the stomach like the crumb. It increases the quantity of the ____, and is more digestible than the crumb, since the ____ has been changed by slow heat to ____ (p. 112). Therefore loaves or biscuit should be (large or small?) and they should (touch or be separated?) in a pan. 7. How can you tell whether the oven has been too hot while the bread was baking? 8. Why can you tell best about the digestibility of bread when you are slicing it? 9. Regulating the heat is the greatest art of the cook. How may the temperature of the oven be lowered by means of the damper? The draft? The fuel?

Exercises in Writing.—Story of a Savage who went to dwell in a City (his trouble with artificial ways). Is it easier to learn Physiology or to practice it? How to make Bread. Describe People seen in an Audience (tell what their appearance suggests). A Scene at a Dinner Table. Thoughts of a Physician on his Round of Visits. A Good Cook. A Bad Cook. Is Cooking a Greater Accomplishment than Piano Playing? Common Causes of Illness. The Influence of Imperfect Digestion upon the Other Organs. Effect of Lack of Muscular Activity. The Way of the Transgressor is Hard. What Fools we Mortals be! Health Fads. Temperance in all Things. The Right Way the Easiest. Looking Back. Looking Forward. Hygiene of the Schoolroom. Patent Medicines. Microbes. Mind Cure. Nervous Women. Dissipated Men. How a Friend of mine lost his Health. Why a Friend of mine is Sound and Strong. Tobacco. It never pays to neglect the Health. Which does more Harm, an Ignorant Cook or an Ignorant Janitor? A Visit to a Sick Room. Alcohol and Crime. Natural Instincts and Appetites; how preserved, how lost. A Lesson about Alcohol based upon the Morning News. Effects of Alcohol upon the Greatness of our Country (workmen, voters, soldiers, children). Adam’s Apothecary Shop. Adam’s Ale (water).