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Popular Books on Natural Science
Popular Books on Natural Scienceполная версия

Полная версия

Popular Books on Natural Science

Язык: Английский
Год издания: 2017
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CHAPTER XIII.

HAS THE MOON INFLUENCE UPON THE WEATHER?

The idea that the moon exercises an influence upon the state of the weather is very general, not only with the people, but also among the better educated. What induces them to entertain it, is not real observation of nature, but a belief which is not without a semblance of truth. If, they say, the moon has enough influence upon our waters to produce tides, it must exercise a still greater influence upon the sea of air surrounding us, and hence it must be of the greatest importance to our weather.

This is, however, an illusion. A long time ago it was proved by Laplace, that tides are caused by the great weight of a liquid. If the ocean were filled with mercury instead of water, the tides would reach a formidable height. Tides, then, do exist in the atmosphere, but in comparison much less than in the water, because the air is so much lighter. It happens that we do not live on the surface of the atmosphere, but in the lowest strata of this airy sea; and in these strata, where the weather manifests itself, the effect of the tides in the upper air is so insignificant, that nothing of it has yet been discovered in spite of most diligent barometer observations.

Learned men have had such a respect for this popular belief, that thorough observations and investigations have been made in order to settle the question.

Those investigations were of three kinds:

1st. What influence with regard to heat and cold has the nearness or remoteness of the moon upon our weather? 2d. What influence has the same upon rain or dryness in the atmosphere? 3d. Has the change of the moon any bearing upon the variability of our weather?

For the reply to these questions, some naturalists have made use of the minutest observations for a period of nearly forty years; during which time the temperature, pressure, and moisture of the air have been measured daily.

These observations have been scrupulously examined; the conclusion arrived at is, that the moon is not quite without influence upon the state of our atmosphere; but this influence is so very small, that it is not brought to bear at all on meteorology.

When the moon is nearest to the earth, it is certainly a little colder than when she is farther off; but the decrease of heat amounts in the average scarcely to one-fifth of a degree, and this is a quantity entirely imperceptible in our weather. As to rain, it is a little less frequent in the time of the moon's greatest distance from the earth; but this difference, too, is imperceptibly small. In one thousand rain-storms there are four hundred and eighty-eight during the moon's greatest distance, five hundred and twelve during her nearest. As to the pressure of the air, it is during the moon's greater distance somewhat greater than when she is nearer, but this difference is still less than the preceding ones, so much so that a common barometer does not even indicate it.

The most thorough investigations have been made about the influence of the waxing and waning moon upon the weather, because it was on this subject that the greatest illusion prevailed. The result here is likewise, that scarcely any difference exists, and that it is a mere superstition for people to maintain, that when the moon changes, the weather changes also. The change in the moon, moreover, does not take place all of a sudden, but with great regularity from day to day, from minute to minute; while the weather, especially with us, changes often very abruptly.

It is therefore certain, that in meteorology one has only to observe the earth and her position with regard to the sun, together with the currents of air and the position of land and water. Other phenomena of the atmosphere may be entirely omitted.

PART VII.

OUR ARTICLES OF FOOD

CHAPTER I.

THE RAPID RENEWAL OF THE BLOOD IS AN ADVANTAGE

Our articles of food are also called articles of life, and very properly so; for that which lives in us is, indeed, nothing but food transformed into ourselves.

According to this, it is very easy to determine what a man must eat in order to live; what kind of food can best maintain his health; what constantly renews his working-power; what compensates for the loss he experiences by emission of breath, perspiration, and excretions.

This easy task many have proposed to themselves. They believe they have solved the problem, if they can but prove that all parts of the human body are fed by the blood; and, the constituents of the blood being well known, they believe they have done enough, if they designate that food as the most proper for man which contains the constituent parts of the blood, or which, by digestion, may be changed into blood.

As a general thing this is true; yet it is not sufficient to give the necessary information about the principal articles of our food.

The poor Irishman, who lives almost exclusively on potatoes, has as much blood in his body as the Englishman, whose workmen threaten him with a strike, if they do not earn enough to have a piece of meat and a good glass of beer for breakfast. The Irishman's blood contains quite the same elements that the Englishman's does, and yet their food is very different; and the Irishman is as justly called "poor," as the Englishman is said to be "well fed."

It is evident that the blood alone does not account for this, nor can it do so. There must be other additional items; and these we shall try to learn before we speak of the different articles of food and their worth.

The first principle which we must set up before all others, runs thus: Nutrition does not depend on the blood, but rather on its quick renewal.

The blood resembles the capital which a man possesses. No one can live on his capital without consuming it; he must live on the interest of the capital; he must live by constantly turning the capital over. And so must it be with the blood. The comparison seems so perfect, that we can illustrate our idea best by an example.

Imagine two merchants, each of whom has but a hundred dollars. Both merchants are therefore equally rich in capital. But there is the following difference between them: the one goes to the country twice a week and buys cattle and brings it to market, where he sells it again. By doing this he realizes every time five dollars on his capital. The other establishes a notion-store, buys himself a hundred dollars' worth of goods, which he sells in a month, and thereby gains twenty-five dollars. Now, which of these two fares the better? The notion-dealer, who with his hundred dollars has earned twenty-five dollars, or the cattle-dealer, who gained but five? Most assuredly the cattle-dealer. For while the other has twenty-five dollars to live on, the cattle-dealer has eight times five, or forty dollars. Whence does this come? In a month the notion-dealer turns over his capital but once, while the cattle-dealer turns his eight times.

The same holds good with the Irishman and the Englishman. Both have the same quantity of blood; it is their capital, and the same for both. But the renewal is not the same. The Englishman works vigorously and eats vigorously. When he works, he spends his capital, his blood; by every blow of the hammer particles of his body are wasted; the activity of his body is great and his appetite is great. He invests his capital again and again in rapid succession, and he takes it in just as rapidly and fares well with it. The poor, unhappy Irishman, however, spends his blood but very slowly; he does not work; he eats potatoes, which, taken alone, are bad food; thus, he invests his capital very slowly and takes it in again very slowly; and though the capital is in both cases the same, its slow renewal is the cause of the Irishman's being miserable, dull, and lazy, while the Englishman is sound in body and soul.

Therefore the blood alone is not all, but its rapid consumption and renewal is the most important object.

CHAPTER II.

DIGESTION

In the preceding article we said that the rapid conversion and waste of the blood is the main point in nutrition. In the examination of food, only such articles ought to be pronounced good and healthy, as are capable of rapidly replacing the blood lost by work and vital activity. It follows from this, that our chemists do not do enough, when they examine the food and determine its worth merely according to its contents; articles of food must be studied also in reference to the rapidity and ease with which they may be converted into blood.

An article that contains little of what the blood needs, but which converts that little rapidly and easily into blood, is much preferable to food which contains many of the constituent parts of the blood, but turns into blood very slowly and with difficulty.

An example will illustrate this better:

It has been proved chemically, that the husks of grain, the pure bran, contain a remarkably large quantity of vegetable albumen and fat; in this particular, bran is richer than even flour, and a distinguished chemist, Millon, in Paris, in 1849, created quite a sensation by his earnest admonition to use bran no longer only to feed cattle, but to use it mixed with flour, as food for man. He calculated minutely and proved irrefutably, that such food must be considered a great advantage, a real blessing.

Although his investigations and computations were correct, it has since been shown that his proposition is false. In his capacity of a chemist he was right; but the stomach has not as much time and patience as a studious chemist. Notwithstanding bran contains much that the blood can use, yet it is of no avail so long as our digestive apparatus is not organized to perform the change of the bran into blood rapidly and easily. If bran leaves our body undigested, which happens even to the strongest, then it is certainly more judicious to give it to cattle; they can digest it well, grow fat and strong upon it, and give us meat, fat, and milk in return.

There is another truth we must constantly keep in view; it is this: Of two like articles of food, the better and more advantageous one to us is that which is digested, or better, converted into blood, the more easily and quickly.

And there is a third truth, which must not be omitted. Let no one for a moment believe, that a great variety of food is something unimportant and indifferent; on the contrary, investigations have shown that uniform food is hurtful, while a constant change is very beneficial to nutrition and health.

Nor must we neglect, by way of conclusion, to mention a very important item, viz.: that taste comes in for a large share, and that a judicious assortment and seasoning of the food is an essential part of good nutrition. The husband provides for his wife, it is true; but, on the other hand, the good housewife who prepares healthy, tasteful meals, does in truth perform a great service, and contributes more to the working power of her husband, than most of men are aware.

After these few preliminaries, we will speak now of the articles themselves; in doing so, we shall keep within the limits of practical life, though we run the risk of transgressing here and there into the domain of our good housewives, and of meddling with what, according to their idea, is not our business.

CHAPTER III.

COFFEE

We come now to consider the various articles of food in detail. We shall take for guide neither the luxurious life of the rich, who, on account of his disordered stomach, constantly tickles his palate with dainties; nor the miserable life of the poor, who, on account of his empty stomach, is bound to find everything palatable. We wish rather to take into consideration the food of that class of people in which the husband works hard to support his family; and where the wife is a good housewife, and cares for the health and strength of her husband and children. In other words, we wish to consider the kind of food called household fare, and speak of the meals as taken every day.

It is customary with most to take coffee in the morning.

Now, what are the qualities of coffee? Is coffee an article of food? Or is it a beverage merely to quench the thirst? Is it a means of warming? Or is it a spice? Medicine? Or perhaps poison?

It is strange that science has not yet reached the truth about these questions.

Coffee has been chemically analyzed, and has been found to contain a peculiar element, caffeine, which has an abundance of nitrogen. It is remarkable also that tea has been found to contain an element called theine, which has the same quantity of nitrogen.

As in some countries tea replaces coffee – this is especially the case in Russia, Holland, England, and America – the great and ingenious naturalist Liebig has come to the conclusion that it is nitrogen which constitutes the chief value of tea and coffee as articles of food; and as our blood needs nitrogen, in order to be able to form our muscles and flesh, coffee, according to Liebig, must be counted among the articles of food.

In later times this view has been attacked. Although it is true that nitrogen is very abundant in coffee, and that we need nitrogen to form muscles, yet it can never be the nitrogen which incites us to the enjoyment of coffee. It is the berry of the coffee that contains the nitrogen; a part of it escapes during the process of roasting; a great part is thrown away with the coffee-grounds, so that the quantity of nitrogen actually left in the infusion is exceedingly small. Besides, if we enjoy in coffee only the nitrogen, we pay very high for it.

In the United States, annually about two hundred and fifty millions of pounds of coffee are used; the cost is estimated at twenty-five millions of dollars. Since the coffee itself is not consumed, but only the infusion, it follows that about 100,000 pounds of nitrogen are consumed at a cost of 250 millions of dollars, which is a terrible waste, considering that for this money seven times as much nitrogen could be taken, if, instead of coffee, meat were used, which contains also a large quantity of nitrogen.

The natural sciences, therefore, show among their scholars professed enemies of coffee. They are, from a medical as well as economical point of view, decidedly opposed to its use. Some have even gone so far as to declare it poisonous; a naturalist by name of Zobel proved that it contains Prussic acid, one of the deadliest poisons. Fortunately we know that this Prussic acid is rendered ineffectual by the ammoniac which coffee contains, and which is used as an antidote against Prussic acid.

Be this as it may, we have reason to esteem coffee very highly. A beverage which has become such a necessity to every nation, is of great importance; and the instinct with which millions and millions of our fellow-men are drawn to its enjoyment, is the best proof that the use of coffee is not hurtful, but advantageous to man; notwithstanding the fact that in some diseases it is forbidden, and that science has not yet succeeded in showing us the real advantage of coffee as a means of food.

CHAPTER IV.

COFFEE AS A MEDICINE

In recent times coffee has been considered, not as an article of food, but partly as a spice and partly as a kind of medicine. Spice it is, inasmuch as it causes, like many other spices, the stomach to secrete an increased quantity of gastric juice. Digestion only takes place when the sides of the stomach secrete a liquid having the quality of digesting food. Owing to this, well-to-do people take after dinner a cup of coffee in order to promote digestion. It is because at night the power of digesting is very much enfeebled – hence the bad sleep after one has eaten something difficult to digest – and because the stomach is relaxed and inactive, that a cup of coffee in the morning refreshes and stimulates the coats of the stomach, and causes there renewed vigor and activity. It is a common observation, that more appetite is felt after coffee than before it. So much for the importance of coffee as a spice. Very justly we ascribe to coffee also a medicinal influence; we consider it a medicine for our mental activity, and for the activity of the nerves.

It is well known that at night coffee dispels fatigue, and that by the use of strong coffee sleep may be banished for a long time. And more; those that are busy mentally, often feel a fresh, invigorating impulse after the enjoyment of coffee; when fatigued with work, they make it a means to recruit their strength. For a similar reason, coffee can animate conversation. When we meet elderly ladies in society, and notice them sitting quietly and talking but in monosyllables, we need not be surprised; they have had no coffee yet! But when, after a little, conversation flows with full force like a rapid stream of water, we may from this safely recognize the mighty influence of coffee; it has loosened not only the tongues, but more – the looks, the hands, nay, the whole body and the whole soul.

Although the mind has rested during the night, we feel in the morning rather sleepy than otherwise, and hence it is, that we are every morning desirous of stimulating our nervous system with a cup of coffee, preparing, as it were, our mind for the day's work. A modern naturalist, as genial as he is learned, Moleschott, ascribes the lately increased consumption of coffee to the greater degree of mental activity, which life in former times did not require to such a high extent as our present age.

We have now sufficiently explained the need of coffee-drinking, and we must confess that all we have said here does not in the least affect our conviction that, according to Liebig, coffee is also nutritive. And no one can help believing this who has seen how old people can subsist on but very little food, provided they can have plenty of coffee. The objection raised, that it would be better for these persons to take the nitrogen contained in coffee in the form of meat, is correct; but, on the other hand, we must stop to ask, whether meat would be good for the stomach at all such times as a cup of coffee is! This would certainly not be the case early in the morning; and if in the coffee we enjoy a beverage which gives us nutriment, strengthens the stomach and at the same time stimulates our mind, we have good reasons to reverence the instinct of man which raised coffee to an essential means of subsistence, and discovered its beneficial influence long before this was done by science.

CHAPTER V.

USEFULNESS AND HURTFULNESS OF COFFEE

Since coffee possesses the quality of stimulating the nervous system, it is a matter of course that in many cases its effect is rather injurious. Phlegmatic people, especially, need coffee, and they are fond of drinking it; for a similar reason it is a favorite beverage in the Orient, where its consumption is immense. But to persons of an excitable temperament the enjoyment of coffee is hurtful; they ought only to take it very weak. With lively children it does not agree at all, and it is very wrong to force them to drink it, as is often done; while elderly people, who are in need of a stimulant for the decreasing activity of their nerves, are right in taking as much of it as they choose.

In households of limited means it is often customary to use succory with coffee. We do not pretend to pronounce this, if taken in moderate quantity, hurtful; but we do say, that it is a poor substitute for coffee, and that there is nothing in it to recommend its use. A far better mixture is milk and sugar, and there is good reason for it; both milk and sugar are articles of food. Milk contains the same ingredients as blood, and sugar is changed in the body into fat, which is indispensable to us, especially to the process of breathing. Having taken no food through the night, the loss our blood has suffered during sleep by perspiration, and the fat which has been lost by respiration, must be compensated for in the morning. For this, milk and sugar in coffee are excellent. It is good for children to have a taste for sweetened milk, or milk-coffee, in the morning. We must not find fault with them if they like it. Nature very wisely gave them a liking for sugar; they need it, because their pulse must be quicker, their respiration stronger, in order to facilitate the assimilation of food in their bodies, and also to promote growth. Not that adults need no sugar; but the sugar necessary for them is formed from the starch contained in their food. For this purpose the digestive apparatus must be strongly developed; with children this is not the case; therefore they are given sugar, instead of the starch to make it from. Many diseases, particularly rickets – prevailing mostly among the children of the poor – are the consequence of feeding the child with bread and potatoes; these contain starch it is true, but the digestive apparatus of children being yet too weak to change them into fat, the result is that the flesh falls away, and the bones grow soft and crooked.

But he who, to promote digestion, takes coffee immediately after dinner, does best not to use sugar or milk; for both, so far from helping digestion, are an additional burden to the full stomach, and disturb its labor more than the coffee can facilitate it.

It is very good to take wheat bread for breakfast. Wheat has nearly twice the quantity of sugar and starch that rye contains, and it is besides easier to digest. And as it is our principal duty in the morning to replace as quickly as possible what we have lost during the night, it is a matter of importance to give the stomach such food as is both nutritive and quickly digested.

CHAPTER VI.

BREAKFAST

Workmen, even those who must perform hard labor, are sufficiently strengthened by coffee and wheat bread in the morning to begin their work. But to be able to continue it, a more substantial breakfast is necessary, since coffee and bread alone would only replace what was lost during the night. On the continent of Europe it is therefore the custom to take coffee, or milk, and bread very early, and, at about nine or ten o'clock a more substantial meal, a kind of lunch.

Breakfast is with but few the principal meal of the day; for those, however, who rise early it is the one taken with the best appetite. This fact ought to induce all to give attention to this meal; especially those who early in the morning have worked hard already, and those who, mindful of the old saying, intend not to idle away the precious morning hours.

"Early to bed and early to riseMakes a man healthy, wealthy and wise,"

To him who is in the habit of laboring, and who loves to labor, an early breakfast has a peculiar charm; and, what is yet more important to him, it tastes well. It is customary with us to eat much bread. Bread has as its principal constituents, starch and sugar, and if it has been well baked, a part of the starch is already saccharine, that is, it is nearly transformed into sugar, thus greatly facilitating the process of digestion. French naturalists have lately written excellent treatises about the change which fresh bread undergoes when it becomes old. They prove that bread is most nutritive, and easiest to digest, when about a day old.

Bread is changed in our bodies partly into fat, as all food is which contains starch. But this formation of fat is greatly facilitated, if we take a little ready-made fat with it. For this purpose we eat butter with our bread. Hence we see that some people are wrong when they believe butter to be a mere luxury; on the contrary, butter is a very important article of food, more especially so to children.

The reason of this is, that the fat performs a conspicuous part in the human body; it serves to keep up the process of respiration. The oxygen which is inhaled, decomposes the fat in our body and from it forms water and carbonic acid. The water evaporates through perspiration; the carbonic acid is exhaled again. Now, if there is fat in us, this perspiration and exhalation will diminish it; but this very act of using up the fat preserves our flesh from being consumed in the process of producing carbonic acid and perspiration, which, if there were no fat, would greatly weaken us. Fat, thus to speak, is the spare-money, while flesh is the capital in the body. Fat itself does not make us strong, while flesh does. But where there is no fat, the processes of perspiration and respiration attack our flesh, which, unless abundantly reinforced, begins to disappear rapidly, while our strength begins to decrease more and more.

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