THE HISTORY OF A MOUTHFUL OF BREAD: And Its Effect on the Organization of Men and Animals.
BY JEAN MACE.
Translated Prom the Eighth French Edition, By Mrs. Alfred Gatty.
EXTRACTS FROM THE PREFACE TO THE ENGLISH EDITION.
The volume of which the following pages are a translation, has been adopted by the University Commission at Paris among their prize books, and has reached an eighth edition. Perhaps these facts speak sufficiently in its favor; but as translator, and to some extent editor, I wish to add my testimony to the great charm as well as merit of the little work. I sat down to it, I must own, with no special predilection in favor of the subject as a suitable one for young people; but in the course of the labor have become a thorough convert to the author's views that such a study—perhaps I ought to add, so pursued as he has enabled it to be—is likely to prove a most useful and most desirable one.
The precise age at which the interest of a young mind can be turned towards this practical branch of natural history is an open question, and not worth disputing about. It may vary even in different individuals. The letters are addressed to a child—in the original even to a little girl—and most undoubtedly, as the book stands, it is fit for any child's perusal who can find amusement in its pages: while to the rather older readers, of whom I trust there will be a great many, I will venture to say that the advantage they will gain in the subject having been so treated as to be brought within the comprehension and adapted to the tastes of a child, is pretty nearly incalculable. The quaintness and drollery of the illustrations with which difficult scientific facts are set forth will provoke many a smile, no doubt, and in some young people perhaps a tendency to feel themselves treated babyishly; but if in the course of the babyish treatment they find themselves almost unexpectedly becoming masters of an amount of valuable information on very difficult subjects, they will have nothing to complain of. Let such young readers refer to even a popular Encyclopaedia for an insight into any of the subjects of the twenty-eight chapters of this volume—"The Heart," "The Lungs," "The Stomach," "Atmospheric Pressure,"—no matter which, and see how much they can understand of it without an amount of preliminary instruction which would require half-a-year's study, and they will then thoroughly appreciate the quite marvellous ingenuity and beautiful skill with which M. Mace has brought the great leading anatomical and physical facts of life out of the depths of scientific learning, and made them literally comprehensible by a child.
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There is one point (independent of the scientific teaching) and that, happily, the only really important one, in which the English translator has had no change to make or desire. The religious teaching of the book is unexceptionable. There is no strained introduction of the subject, but there is throughout the volume an acknowledgment of the Great Creator of this marvellous work of the human frame, of the daily and hourly gratitude we owe to Him, and of the utter impossibility of our tracing out half his wonders, even in the things nearest to our senses, and most constantly subject to observation. M. Mace will help, and not hinder the humility with which the Christian naturalist lifts one veil only to recognise another beyond.
It will be satisfactory to any one who may be inclined to wonder how a lady can feel sure of having correctly translated the various scientific and anatomical statements contained in the volume, to know that the whole has been submitted to the careful revision of a medical friend, to whom I have reason to be very grateful for valuable explanations and corrections whenever they were necessary. In the same way the chapter on "Atmospheric Pressure," where, owing to the difference between French and English weights and measures, several alterations of illustrations, etc., had to be made, has received similar kind offices from the hands of a competent mathematician.
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Ecclesfield, June, 1864.
NOTE TO THE AMERICAN EDITION.
In May '66, the seventeenth edition of this work was on sale in Paris. The date of Mrs. Gatty's preface, it will be observed, is June '64, and at that time, the eighth French edition only had been reached. That it should be a popular book and command large sale wherever it is known, will not surprise any one who reads it: the only remarkable circumstance about it is, that it should not have been republished here long ere this. Even this may probably be accounted for, on the supposition that the title under which the translation was published in England, was so unmeaning—conveying not the slightest idea of the contents of the book—that none of our publishers even ventured to hand it over to their "readers" to examine.
The author's title, The History of a Mouthful of Bread, while falling far short of giving a clear notion of the entire scope of the work, is shockingly diluted and meaningless, when translated The History of a Bit of Bread!
To the translation of Mrs. Gatty, which is in the main an excellent one, for she has generally seized upon the idea of the author and rendered it with singular felicity, it may be very properly objected that she has taken some liberties with the text when there was any conflict of opinion between herself and her author, and has given her own ideas instead of his, which is, probably, what she refers to when she calls herself "to some extent editor."
The reader of this edition will, in all these cases, find the thought of the author and not that of his translator; for the reason that a careful examination of the original has convinced the publisher that in every instance the author was to be preferred to the translator, to say nothing of the right an author may have to be faithfully translated.
Besides making these restorations, the copy from which this edition was printed has been carefully compared with the last edition of the author and a vast number of corrections made, and in its present shape it is respectfully submitted and dedicated to every one (whose name is legion, of course) who numbers among his young friends a "my dear child" to present it to.
FIRST PART MAN.
II.—THE HAND III.—THE TONGUE IV.—THE TEETH V.—THE TEETH (continued) VI.—THE TEETH (continued) VII.—THE THROAT VIII.—THE STOMACH IX.—THE STOMACH (continued) X.—THE INTESTINAL CANAL XI.—THE LIVER XII.—THE CHYLE XIII.—THE HEART XIV.—THE ARTERIES XV.—THE NOURISHMENT OF THE ORGANS XVI.—THE ORGANS XVII.—ARTERIAL AND VENOUS BLOOD XVIII.—ATMOSPHERIC PRESSURE XIX.—THE ACTION OF THE LUNGS XX.—CARBON AND OXYGEN XXI.—COMBUSTION XXII.—ANIMAL HEAT XXIII.—ACTION OF THE BLOOD UPON THE ORGANS XXIV.—THE WORK OF THE ORGANS XXV.—CARBONIC ACID XXVI.—ALIMENTS OF COMBUSTION XXVII.—ALIMENTS OF NUTRITION (continued)—NITROGEN OR AZOTE XXVIII.—COMPOSITION OF THE BLOOD
XXIX.—CLASSIFICATION OF ANIMALS XXX.—MAMMALIA (Mammals) XXXI.—MAMMALIA. (Mammals)—continued XXXII.—MAMMALIA—continued XXXIII.—MAMMALIA—continued XXXIV.—AVES. (Birds) XXXV.—REPTILIA. (Reptiles) XXXVI.—PISCES. (Fishes) XXXVII.—INSECTA. (Insects) XXXVIII.—CRUSTACEA—MOLLUSKA. (Crustaceans and Mollusks) XXXIX.—VERMES—ZOOPHYTA. (Worms and Zoophytes) XL.—THE NOURISHMENT OF PLANTS CONCLUSION
I am going to tell you, my dear child, something of the life and nature of men and animals, believing the information may be of use to you in after-life, besides being an amusement to you now.
Of course, I shall have to explain to you a great many particulars which are generally considered very difficult to understand, and which are not always taught even to grown-up people. But if we work together, and between us succeed in getting them clearly into your head, it will be a great triumph to me, and you will find out that the science of learned men is more entertaining for little girls, as well as more comprehensible, than it is sometimes supposed to be. Moreover, you will be in advance of your years, as it were, and one day may be astonished to find that you had mastered in childhood, almost as a mere amusement, some of the first principles of anatomy, chemistry, and several other of the physical sciences, as well as having attained to some knowledge of natural history generally.
I begin at once, then, with the History of a Mouthful of Bread, although I am aware you may be tempted to exclaim, that if I am going to talk only about that, I may save myself the trouble. You know all about it, you say, as well as I do, and need not surely be told how to chew a bit of bread-and-butter! Well, but you must let me begin at the very beginning with you, and you have no notion what an incredible number of facts will be found to be connected with this chewing of a piece of bread. A big book might be written about them, were all the details to be entered into.
First and foremost—Have you ever asked yourself why people eat?
You laugh at such a ridiculous question.
"Why do people eat? Why, because there are bonbons, and cakes, and gingerbread, and sweetmeats, and fruit, and all manner of things good to eat." Very well, that is a very good reason, no doubt, and you may think that no other is wanted. If there were nothing but soup in the world, indeed, the case would be different. There might be some excuse then for making the inquiry.
Now, then, let us suppose for once that there is nothing in the world to eat but soup; and it is true that there are plenty of poor little children for whom there is nothing else, but who go on eating nevertheless, and with a very good appetite, too, I assure you, as their parents know but too well very often. Why do people eat, then, even when they have nothing to eat but soup? This is what I am going to tell you, if you do not already know.
The other day, when your mamma said that your frock "had grown" too short, and that you could not go out visiting till we had given you another with longer sleeves and waist, what was the real cause of this necessity?
What a droll question, you say, and you answer—"Because I had grown, of course."
To which I say "of course," too; for undoubtedly it was you who had outgrown your frock. But then I must push the question further, and ask—How had you grown?
Now you are puzzled. Nobody had been to your bed and pulled out your arms or your legs as you lay asleep. Nobody had pieced a bit on at the elbow or the knee, as people slip in a new leaf to a table when there is going to be a larger party than usual at dinner. How was it, then, that the sleeves no longer came down to your wrists, or that the body only reached your knees? Nothing grows larger without being added to, any more than anything gets smaller without having lost something; you may lay that down as a rule, once for all. If, therefore, nothing was added to you from without, something must have been added to you from within. Some sly goblin, as it were, must have been cramming into your frame whatever increase it has made in arms, legs, or anything else. And who, do you think, this sly goblin is?
Why, my dear, it is yourself!
Ay! Bethink you, now, of all the bread-and-butter, and bonbons, and gingerbread, and cakes, and sweetmeats, and even soup and plain food (the soup and plain food being the most useful of all) which you have been sending, day by day, for some time past, down what we used to call "the red lane," into the little gulf below. What do you think became of them when they got there? Well, they set to work at once, without asking your leave, to transform themselves into something else; and gliding cunningly into all the holes and corners of your body, became there, each as best he might, bones, flesh, blood, etc., etc. Touch yourself where you will, it is upon these things you lay your hand, though, of course, without recognizing them, for the transformation is perfect and complete. And it is the same with everybody.
Look at your little pink nails, which push out further and further every morning; examine the tips of your beautiful fair hair, which gets longer and longer by degrees; coming out from your head as grass springs up from the earth; feel the firm corners of your second teeth, which are gradually succeeding those which came to you in infancy; you have eaten all these things, and that no long time ago.
Nor are you children the only creatures who are busy in this way. There is your kitten, for instance, who a few months ago was only a tiny bit of fur, but is now turning gradually into a grown-up cat. It is her daily food which is daily becoming a cat inside her—her saucers of milk now, and very soon her mice, all serve to the same end.
The large ox, too, of whom you are so much afraid, because you cannot as yet be persuaded what a good-natured beast he really is, and how unlikely to do any harm to children who do none to him—that large ox began life as a small calf, and it is the grass which he has been eating for some time past which has transformed him into the huge mass of flesh you now see, and which by-and-by will be eaten by man, to become man's flesh in the same manner.
But, further, still: Even the forest trees, which grow so high and spread so wide, were at first no bigger than your little finger, and all the grandeur and size you now look upon, they have taken in by the process of eating. "What, do trees eat?" you ask.
Verily, do they; and they are, by no means, the least greedy of eaters, for they eat day and night without ceasing. Not, as you may suppose, that they crunch bonbons, or anything else as you do; nor is the process with them precisely the same as with you. Yet you will be surprised hereafter, I assure you, to find how many points of resemblance exist between them and us in this matter. But we will speak further of this presently.
Now, I think you must allow that there are few fairytales more marvellous than this history of bread and meat turning into little boys and girls, milk and mice turning into cats, and grass into oxen! And I call it a history, observe, because it is a transformation that never happens suddenly, but by degrees, as time goes on.
Now, then, for the explanation. You have heard, I dare say, of those wonderful spinning-machines which take in at one end a mass of raw cotton, very like what you see in wadding, and give out at the other a roll of fine calico, all folded and packed up ready to be delivered to the tradespeople. Well, you have within you, a machine even more ingenious than that, which receives from you all the bread-and-butter and other sorts of food you choose to put into it, and returns it to you changed into the nails, hair, bones and flesh we have been talking about, and many other things besides; for there are quantities of things in your body, all different from each other, which you are manufacturing in this manner all day long, without knowing anything about it. And a very fortunate thing this is for you: for I do not know what would become of you if you had to be thinking from morning to night of all that requires to be done in your body, as your mother has to look after and remember all that has to be done in the house. Just think what a relief it would be to her to possess a machine which should sweep the rooms, cook the dinners, wash the plates, mend torn clothes, and keep watch over everything without giving her any trouble; and, moreover, make no more noise or fuss than yours does, which has been working away ever since you were born without your ever troubling your head about it, or probably even knowing of its existence! Just think of this and be thankful.
But do not fancy you are the only possessor of a magical machine of this sort. Your kitten has one also, and the ox we were speaking of, and all other living creatures. And theirs render the same service to them that yours does to you, and much in the same way; for all these machines are made after one model, though with certain variations adapted to the differences in each animal. And, as you will see by-and-by, these variations exactly correspond with the different sort of work that has to be done in each particular case. For instance, where the machine has grass to act upon, as in the ox, it is differently constructed from that in the cat which has to deal with meat and mice. In the same way in our manufactories, though all the spinning-machines are made upon one model, there is one particular arrangement for those which spin cotton, another for those which spin wool, another for flax, and so on.
You have possibly noticed already, without being told, that all animals are not of equal value; or, at least, to use a better expression, they have not all had the same advantages bestowed on them. The dog, for instance, that loving and intelligent companion, who almost reads your thoughts in your eyes, and is as affectionate and obedient to his master as it were to be wished all children were to their parents—this dog is, as you must own, very superior, in all ways, to the frog, with its large goggle eyes and clammy body, hiding itself in the water as soon as you come near it. But again, the frog, which can come and go as it likes, is decidedly superior to the oyster, which has neither head nor limbs, and lives all alone, glued into a shell, in a sort of perpetual imprisonment.
Now the machine I have been telling you about is found in the oyster and in the frog as well as in the dog, only it is less complicated, and therefore less perfect in the oyster than in the frog; and less perfect again in the frog than in the dog; for as we descend in the scale of animals we find it becoming less and less elaborate—losing here one of its parts, there another, but nevertheless remaining still the same machine to all intents and purposes; though by the time it has reached its lowest condition of structure we should hardly be able to recognize it again, if we had not watched it through all its gradations of form, and escorted it, as it were, from stage to stage.
Let me make this clear to you by a comparison.
You know the lamp which is lit every evening on the drawing-room table, and around which you all assemble to work or read. Take off first the shade, which throws the light on your book—then the glass which prevents it smoking—then the little chimney which holds the wick and drives the air into the flame to make it burn brightly. Then take away the screw, which sends the wick up and down; undo the pieces one by one, until none remain but those absolutely necessary to having a light at all—namely, the receptacle for the oil and the floating wick which consumes it.
Now if any one should come in and hear you say, "Look at my lamp," what would he reply? He would most likely ask at once, "What lamp?"—for there would be very little resemblance to a lamp in that mere ghost of one before him.
But to you, who have seen the different parts removed one after another, that wick soaked in oil (let your friend shake his head about it as he pleases) will still be the lamp to you, however divested of much that made it once so perfect, and however dimly it may shine in consequence.
And this is exactly what happens when the machine we are discussing is examined in the different grades of animals. The ignoramus who has not followed it through its changes and reductions cannot recognize it when it is presented to him in its lowest condition; but any one who has carefully observed it throughout, knows that it is, in point of fact, the same machine still.
This, then, is what we are now going to look at together, my dear little girl. We will study first, piece by piece, the exquisite machine within ourselves, which is of such unceasing use to us as long as we do not give it more than a proper share of work to perform. Do you understand? We will see what becomes of the mouthful of bread which you place so coolly between your teeth, as if when that was done nothing further remained to be thought about. We will trace it in its passage through every part of the machine, from beginning to end. It will therefore be simply only the History of a Mouthful of Bread I am telling you, even while I seem to be talking of other matters; for to make that comprehensible I shall have to enter into a good many explanations.
And when you have thoroughly got to understand the history of what you eat yourself, we will look a little into the history of what other animals eat, beginning by those most like ourselves, and going on to the rest in regular succession downwards. And while we are on the subject, I will say a word or two on the way in which vegetables eat, for, as you remember, I have stated that they do eat also.
Do you think this is likely to interest you, and be worth the trouble of some thought and attention?
Perhaps you may tell me it sounds very tedious, and like making a great fuss about a trifle; that you have all your life eaten mouthfuls of bread without troubling yourself as to what became of them, and yet have not been stopped growing by your ignorance, any more than the little cat, who knows no more how it happens than you do.
True, my dear; but the cat is only a little cat, and you are a little girl. Up to the present moment you and she have known, one as much as the other on this subject, and on that point you have therefore had no superiority over her. But she will never trouble herself about it, and will always remain a little cat. You, on the contrary, are intended by God to become something more in intelligence than you are now, and it is by learning more than the cat that you will rise above her in this respect. To learn, is the duty of all men, not only for the pleasure of curiosity and the vanity of being called learned, but because in proportion to what we learn we approach nearer to the destiny which God has appointed to man, and when we walk obediently in the path which God himself has marked out for us, we necessarily become better.
It is sometimes said to grown-up people, that it is never too late to learn. To children one may say that it is never too early to learn. And among the things which they may learn, those which I want now to teach you have the double merit of being, in the first place amusing, and afterwards, and above all, calculated to accustom you to think of God, by causing you to observe the wonders which He has done. Sure am I that when you know them you will not fail to admire them; moreover I promise your mother that you will be all the better, as well as wiser, for the study.
At the foot of the mountains, from whence I write to you, my dear child, when we want to show the country to a stranger, we commence by making him climb one of the heights, whence he may take in at a glance the whole landscape below, all the woods and villages scattered over the plain, even up to the blue line of the Rhine, which stretches out to the distant horizon. After this he will easily find his way about.
It is to the top of a mountain equally useful that I have just led you. It has cost you some trouble to climb with me. You have had to keep your eyes very wide open that you might see to the end of the road we had to go together. Now then, let us come down and view the country in detail. Then we shall go as if we were on wheels.
And now let us begin at the beginning:
Well, doubtless, as the subject is eating, you will expect me to begin with the mouth.
Wait a moment; there is something else first. But you are so accustomed to make use of it, that you have never given it a thought, I dare say.
It is not enough merely that one should have a mouth; we must be able to put what we want within it. What would you do at dinner, for instance, if you had no hands?
The hand is then the first thing to be considered.
I shall not give you a description of it; you know what it is like. But what, perhaps, you do not know, because you have never thought about it, is, the reason why your hand is a more convenient, and consequently more perfect, instrument than a cat's paw, for instance, which yet answers a similar purpose, for it helps the cat to catch mice.
Among your five fingers there is one which is called the thumb, which stands out on one side quite apart from the others. Look at it with respect; it is to these two little bones, covered over with a little flesh, that man owes part of his physical superiority to other animals. It is one of his best servants, one of the noblest of God's gifts to him. Without the thumb three-fourths (at least) of human arts would yet have to be invented; and to begin with, the art not only of carrying the contents of one's plate to one's mouth, but of filling the plate (a very important question in another way) would, but for the thumb, have had difficulties to surmount of which you can form no idea.
Have you noticed that when you want to take hold of anything (a piece of bread, we will say, as we are on the subject of eating), have you noticed that it is always the thumb who puts himself forward, and that he is always on one side by himself, whilst the rest of the fingers are on the other? If the thumb is not helping, nothing remains in your hand, and you don't know what to do with it. Try, by way of experiment, to carry your spoon to your mouth without putting your thumb to it, and you will see what a long time it will take you to get through a poor little plateful of broth. The thumb is placed in such a manner on your hand that it can face each of the other fingers one after another, or all together, as you please; and by this we are enabled to grasp, as if with a pair of pincers, whatever object, whether large or small. Our hands owe their perfection of usefulness to this happy arrangement, which has been bestowed on no other animal, except the monkey, our nearest neighbor.
I may even add, while we are about it, that it is this which distinguishes the hand from a paw or a foot. Our feet, which have other things to do than to pick up apples or lay hold of a fork, our feet have also each five fingers, but the largest cannot face the others; it is not a thumb, therefore, and it is because of this that our feet are not hands. Now the monkey has thumbs on the four members corresponding to our arms and legs, and thus we may say that he has hands at the end of his legs as well as of his arms. Nevertheless, he is not on that account better off than we are, but quite the contrary. I will explain this to you presently.
To return to our subject. You see that it was necessary, before saying anything about the mouth, to consider the hand, which is the mouth's purveyor. Before the cook lights the fires the maid must go to market, must she not? And it is a very valuable maid that we have here: what would become of us without her?
If we were in the habit of giving thought to everything, we should never even gather a nut without being grateful to the Providence which has provided us with the thumb, by means of which we are able to do it so easily.
But however well I may have expressed it, I am by no means sure, after all, that I have succeeded in showing you clearly, how absolutely necessary our hand is to us in eating, and why it has the honor to stand at the beginning of the history of what we eat.
It still appears to you, I suspect, that even if you were to lose the use of your hands you would not, for all that, let yourself die of hunger.
This is because you have not attended to another circumstance, which nevertheless demands your notice—namely, that from one end of the world to the other, quantities of hands are being employed in providing you with the wherewithal to eat.
To go on further: Have you any idea how many hands have been put in motion merely to enable you to have your coffee and roll in the morning? What a number, to be sure, over this cup of coffee (which is a trifle in comparison with the other food you will consume in the course of the day); from the hand of the negro who gathered the coffee crop to that of the cook who ground the berries, to say nothing of the hand of the sailor who guided the ship which bore them to our shores. Again, from the hand of the laborer who sowed the corn, and that of the miller who ground it into flour, to the hand of the baker who made it into a roll. Then the hand of the farmer's wife who milked the cow, and the hand of the refiner who made the sugar; to say nothing of the many others who prepared his work for him, and I know not how many more.
How would it be, then, if I were to amuse myself by counting up all the hands that are wanted to furnish—
The sugar-refiner's manufactory, The milkmaid's shed, The baker's oven, The miller's mill, The laborer's plough, The sailor's ship?
And even now is there nothing we have forgotten? Ah, yes! the most important of all the hands to you;—the hand which brings together for your benefit the fruits of the labor of all the others—the hand of your dear mother, always active, always ready, that hand which so often acts as yours when your own is awkward or idle.
Now, then, you see how you might really manage to do without those two comparatively helpless little paws of yours (although there is a thumb to each), without suffering too much for want of food. With such an army of hands at work, in every way, to furnish provision for that little mouth, there would not be much danger.
But cut off your cat's fore paws—oh dear! what am I saying? Suppose, rather, that she has not got any, and then count how many mice she will catch in a day. The milk you give her is another matter, remember. Like your cup of coffee, that is provided for her by others.
Believe me, if you were suddenly left all alone in a wood, like those pretty squirrels who nibble hazel-nuts so daintily, you would soon discover, from being thus thrown upon your own resources, that the mouth is not the only thing required for eating, and that whether it be a paw or a hand, there must always be a servant to go to market for Mr. Mouth, and to provide him with food.
Happily, we are not driven to this extremity. We take hold of our coffee-biscuit between the thumb and forefinger, and behold it is on its road—Open the mouth, and it is soon done!
But before we begin to chew, let us stop to consider a little.
The mouth is the door at which everything enters. Now, to every well-kept door there is a doorkeeper, or porter. And what is the office of a well-instructed porter? Well, he asks the people that present themselves, who they are, and what they have come for; and if he does not like their appearance, he refuses them admittance. We too, then, to be complete, need a porter of this sort in our mouths, and I am happy to say we have one accordingly. I wonder whether you know him? You look at me quite aghast! Oh, ungrateful child, not to know your dearest friend! As a punishment, I shall not tell you who he is to-day. I will give you till to-morrow to think about it.
Meanwhile, as I have a little time left, I will say one word more about what we are going to look at together. It would hardly be worth while to tell you this pretty story which we have begun, if from time to time we were not to extract a moral from it. And what is the moral of our history to-day?
It has more than one.
In the first place it teaches you, if you never knew it before, that you are under great obligations to other people, indeed to almost everybody, and most of all perhaps to people whom you may be tempted to look down upon. This laborer, with his coarse smock-frock and heavy shoes, whom you are so ready to ridicule, is the very person who, with his rough hand, has been the means of procuring for you half the good things you eat. That workman, with turned-up sleeves, whose dirty black fingers you are afraid of touching, has very likely blackened and dirtied them in your service. You owe great respect to all these people, I assure you, for they all work for you. Do not, then, go and fancy yourself of great consequence among them—you who are of no use in any way at present, who want everybody's help yourself, but as yet can help nobody.
Not that I mean to reproach you by saying this. Your turn has not come yet, and everybody began like you originally. But I do wish to impress upon you that you must prepare yourself to become some day useful to others, so that you may pay back the debts which you are now contracting.
Every time you look at your little hand, remember that you have its education to accomplish, its debts of honor to repay, and that you must make haste and teach it to be very clever, so that it may no longer be said of you, that you are of no use to anybody.
And then, my dear child, remember that a day will come, when the revered hands that now take care of your childhood—those hands which to-day are yours, as it were—will become weak and incapacitated by age. You will be strong, then, probably, and the assistance which you receive now, you must then render to her, render it to her as you have received it—that is to say, with your hands. It is the mother's hand which comes and goes without ceasing about her little girl now. It is the daughter's hand which should come and go around the old mother hereafter—her hand and not another's.
Here again, my child, the mouth is nothing without the hand. The mouth says, "I love," the hand proves it.
Now, about this doorkeeper, or porter, as we will call him, of the mouth. I do not suppose you have guessed who he is; so I am going to tell you.
The porter who keeps the door of the mouth is the sense of taste.
It is he who does the honors of the house so agreeably to proper visitors, and gives such an unscrupulous dismissal to unpleasant intruders. In other words, it is by his directions that we welcome so affectionately with tongue and lips whatever is good to eat, and spit out unhesitatingly whatever is unpleasant.
I could speak very ill of this porter if I chose; which would not be very pleasant for certain little gourmands that I see here, who think a good deal too much of him. But I would rather begin by praising him. I can make my exceptions afterwards.
In the history I am going to give you, my dear child, there is one thing you must never lose sight of, even when I do not allude to it; and that is, that everything we shall examine into, has been expressly arranged by God for the good and accommodation of our being in this world; just as a cradle is arranged by a mother for the comfort of her baby. We must look upon all these things, therefore, as so many presentsfrom the Almighty himself; and abstain from speaking ill of them, were it only out of respect for the hand which has bestowed them.
Moreover, there is a very easy plan by which we may satisfy ourselves of the usefulness and propriety of these gifts—namely, by considering what would become of us if we were deprived of any one of them.
Suppose, for instance, that you were totally deficient in the sense of taste, and that when you put a piece of cake into your mouth, it should create no more sensation in you than when you held it in your hand?
You would not have thought of imagining such a case yourself, I am aware; for it never comes into a child's head to think that things can be otherwise than as God has made them. And in that respect children are sometimes wiser than philosophers. Nevertheless, we will suppose this for once, and consider what would happen in consequence.
Well, in the first place, you would eat old mouldy cake with just the same relish as if it were fresh; and this mouldy cake, which now you carefully avoid because it is mouldy, is very unwholesome food, and would poison you were you to eat a great deal of it.
I give this merely as an instance, but it is one of a thousand. And although, with regard to eatables, you only know such as have been prepared either in shops or in your mamma's kitchen, still you must be aware there are many we ought to avoid, because they would do no good in our stomachs, and that we should often be puzzled to distinguish these from others, if the sense of taste did not warn us about them. You must admit, therefore, that such warnings are not without their value.
In short, it is a marvellous fact that what is unfit for food, is almost always to be recognized as it enters the mouth, by its disagreeable taste; a further proof that God has thought of everything. Medicines, it is true, are unpleasant to the taste, and yet have to be swallowed in certain cases. But we may compare them to chimney-sweepers, who are neither pretty to look at, nor invited into the drawing-room; but who, nevertheless, are from time to time let into the grandest houses by the porters—though possibly with a grimace—because their services are wanted. And in the same way medicines have to be admitted sometimes—despite their unpleasantness—because they, too, have to work in the chimney. Taste does not deceive you about them, however; they are not intended to serve as food. If any one should try to breakfast, dine, and sup upon physic he would soon find this out.
Besides, I only said almost always, in speaking of unwholesome food making itself known to us by its nasty taste; for it is an unfortunate truth that men have invented a thousand plans for baffling their natural guardian, and for bringing thieves secretly into the company of honest people. They sometimes put poison, for instance, into sugar—as is too often done in the case of those horrible green and blue sugar plums, against which I have an old grudge, for they poisoned a friend whom I loved dearly in my youth. Such things as these pass imprudently by the porter, who sees nothing of their real character—Mr. Sugar concealing the rogues behind him.
Moreover, we are sometimes so foolish as not to leave the porter time to make his examination. We swallow one thing after another greedily, without tasting; and such a crowd of arrivals, coming in with a rush, "forces the sentry," as they say; and whose fault is it, if, after this, we find thieves established in the house?
But animals have more sense than we have.
Look at your kitten when you give her some tit-bit she is not acquainted with—how cautiously and gently she puts out her nose, so as to give herself time for consideration. Then how delicately she touches the unknown object with the tip of her tongue, once, twice, and perhaps three times. And when the tip of the tongue has thus gone forward several times to make observations (for this is the great post of observation for the cat's porter as well as for ours), she ventures to decide upon swallowing, but not before. If she has the least suspicion, no amount of coaxing makes any difference to her; you may call "puss, puss," for ever; all your tender invitations are useless, and she turns away.
Very good; here then is one little animal, at least, who understands for what end she has received the sense of taste, and who makes a reasonable use of it. Very different from some children of my acquaintance, who heedlessly stuff into their mouths whatever comes into their hands, without even taking the trouble to taste it, and who would escape a good many stomach-aches, if nothing else, if they were as sensible as Pussy.
This is the really useful side of the sense of taste; but its agreeable side, which is sufficiently well known to you, is not to be despised either, even on the grounds of utility.
You must know, between ourselves, that eating would be a very tiresome business if we did not taste what we are eating; and I can well imagine what trouble mammas would have in persuading their children to come to dinner or tea, if it were only a question of working their little jaws, and nothing further. What struggles—what tears! And setting aside children, who are by no means always the most disobedient to the will of a good GOD, how few men would care to stop in the midst of their occupations, to go and grind their teeth one against another for half-an-hour, if there were not some pleasure attached to an exercise not naturally amusing in itself? Ay, ay, my dear child, were it not for the reward in pleasure which is given to men when they eat, the human race, who as a whole do not live too well already, would live still worse. And it is necessary that we should be fed, and well fed too, if we would perform properly here below the mission which we have received from above.
Yes, "reward" was the word I used. Now it seems absurd to you, perhaps, that it should be necessary to reward a man for eating a good dinner? Well, well, GOD has been more kind to him, then, than you would be. To every duty imposed by Him upon man, He has joined a pleasure as a reward for fulfilling it. How many things should I not have to say to you on this subject, if you were older? For the present, I will content myself with making a comparison.
When a mother thinks her child is not reasonable enough to do, of her own accord, something which it is nevertheless important she should do, as learning to read, for instance, or to work with her needle, &c., she comes to the rescue with rewards, and gives her a plaything when she has done well. And thus GOD, who had not confidence enough in man's reason to trust to it alone for supplying the wants of human nature, has placed a plaything in the shape of pleasure after every necessity; and in supplying the want, man finds the reward.
You will hardly believe that what I have here explained to you so quietly by a childish comparison, has been, and alas! still is, the subject of terrible disputes among grown-up people. If hereafter they reach your ears, remember what I have told you now, viz., that the pleasure lodged in the tongue and its surroundings, is a plaything, but a plaything given to us by GOD; and that we must use it accordingly.
If a little girl has had a plaything given to her by her mother, would she think to please her by breaking it or throwing it into a corner? No, certainly not: she would know that in so doing she would be going directly against her mother's intentions and wishes. Nevertheless she would amuse herself with it in play hours, with an easy conscience, and, if she is amiable, she will remember while she does so, that it comes to her from her mother, and will thank her at the bottom of her heart.
It is the same with man, of whose playthings we are speaking.
But, moreover, this little girl (it is taken for granted that she is a good little girl) will not make the plaything the business of her whole day, the object of all her thoughts; she will not forget everything for it, she will leave it unhesitatingly when her mamma calls her. Neither will she wish to be alone in her enjoyments, but will gladly see her little friends also enjoy similar playthings, because she thinks that what is good for her must be good for others too.
It is thus that man should do with his playthings; but, alas! this is what he does not by any means always do with them, and hence a great deal has been said against them. Little girls, in particular, are apt to fail on this point, and that is how the dreadful word gluttony came to be invented. For the same reason, also, people get punished from time to time; such punishments being the consequence of the misuse I speak of.
If people who call to see your mamma were, instead of going straight up stairs to her, to establish themselves at the lodge with the porter, and stay there chatting with him, do you think she would be much flattered by their visits? And yet this is exactly what people do who, when eating, attend only to the porter. He is so pleasant, this porter; he says such pretty things to you, that you go on talking to him just as if he were the master of the house, who, meanwhile, has quite gone out of your head.
You heap sugar-plums upon sugar-plums, cakes upon cakes, sweetmeats upon sweetmeats—everything that pleases the porter, but is of no use whatever to the master of the house. And then what happens? The master gets angry sometimes, and no wonder. Mr. Stomach grows weary of these visits, which are of no use to him. He rings all the bells, makes no end of a noise in the house, and forces that traitor of a porter who has engrossed all his company, to do penance. You are ill—your mouth is out of order—you have no appetite for anything. The mamma has taken away the plaything which has been misused, and when she gives it back, there must be great care taken not to do the same thing over again.
I have thought it only right, my dear child, in telling you the history of eating, to give to this little detail of its beginning, a place proportioned to your interest in it. You see by what I have said, that you are not altogether wrong in following your taste; but neither must it be forgotten that this part of the business is not in reality the most important; that a plaything is but a plaything, and that the porter is not the master of the house.
Now that we have made our good friend's acquaintance, we will wish him farewell, and I will presently introduce you to his companions of the antechamber, who are ranged on the two sides of the door, to make the toilettes for the visitors who present themselves, and to put them in order for being received in the drawing-room. You will see there some jolly little fellows, who are also very useful in their way, and whose history is no less curious. They are called TEETH.
When you were quite little, my dear child, and still a nursling, you had nothing behind your lips but two little rosy bars, which were of no service for gnawing an apple, as they were not supplied with teeth. You had no need of these then, since nothing but milk passed your lips, neither had your nurse bargained for your having teeth to bite with. You see that God provides for everything, as I have already said, and shall often have occasion to point out to you.
But by degrees the little infant grew into a great girl, and it became necessary to think of giving her something more solid than milk to eat; and for this purpose she required teeth. Then some little germs, which had lain dormant, concealed within the jaws, awoke one after another, like faithful workmen when they hear the striking of the clock. Each set to work in his little cell, and with the help of some phosphorus and some lime, it began to make itself a kind of white armour, as hard as a stone, which grew larger from day to day.
You know what lime is; that sort of white pulp which you have seen standing in large troughs where the masons are building houses, andwhich they use in making mortar; it is with this that your little masons build your teeth.
As to phosphorus, I am afraid you may never have seen any; but you may have heard it spoken of. It is sold at the druggist's in the form of little white sticks, about as thick as your finger; they have a disagreeable, garlicky smell, and are obliged to be kept in jars of water, because they seize every opportunity of taking fire; so I advise you, if ever you do see any phosphorus, not to meddle with it—for in burning, it sticks closely to the skin, and there is the greatest difficulty in the world in extinguishing it, and the burns it makes are fearful. I give you this caution, because phosphorus possesses a very curious property, which might attract little girls. Wherever it is rubbed, in the dark, on a door, or on a wall, it leaves a luminous trail of a very peculiar appearance, which has been called phosphorescent, from the name of the substance which produces it. And in this way one can write on walls in letters of fire, to the terror of cowards. Now, come; if you will promise to be very wise, and only to make the experiment when your mamma is present, I will teach you how to make phosphorescent lights without having to go to the druggist's! There is a small quantity of phosphorus in lucifer matches, which their garlicky smell proves. Rub them gently in the dark on a bit of wood, and you will see a ray of light which will shine for some moments. But mind, you must not play at that game when you are alone; it is a dangerous amusement, and one hears every day of terrible accidents caused by disobedient children playing with lucifer matches. And while we are on the subject, let me warn you against putting them into your mouth. Phosphorus is a poison, and such a powerful one that people poison rats with bread-crumb balls in which it has been introduced.
"Oh dear me! and that poison makes part of our teeth?"
Exactly so, and it even forms part of all our bones, and of the bones of all animals; the best proof of which is, that the phosphorus of lucifer matches has been procured out of bones from the slaughter-house. One could make it from the teeth of little girls if one could get enough of them.
Now I see what puzzles you, and well it may. You are asking yourself how those little tooth-makers, the gums, get hold of this terrible phosphorus, which is set on fire by a mere nothing, and which we dare not put into our mouths; where do they find the lime which I also protest is not fit to eat, and yet of which we have stores from our heads to our feet?
It is very surprising, too, to think of its being forthcoming in the jaws just when it is wanted there.
You begin to perceive that there are many things to be learnt before we come to the end of our history, and that we find ourselves checked at every step; now listen, for we are coming to something very important.
In distant country-seats, where people are thrown entirely upon their own resources, they must be provided beforehand with all that is requisite for repairing the building; and there is, accordingly, a person called a steward, who keeps everything under lock and key, and distributes to the workmen whatever materials they may require. Thus, the steward gives tiles to the slater, planks to the carpenter, colors to the painter, lime and bricks to the mason—the very same lime that we have in our teeth—in fact, he has got everything that can be wanted in his storehouse, and it is to him that every one applies in time of need.
Now our body also is a mansion, and has its steward too. But what a steward—how active! what a universal genius I how inefficient by comparison are the stewards of the greatest lords! He goes, he comes, he is everywhere at once; and this really, and not as we use the phrase in speaking of a merely active man: for the being everywhere at once is in this case, a fact. He keeps everything, not in a storehouse, but what is far better, in his very pockets, which he empties by degrees as he goes about, distributing their contents without ever making a mistake, without stopping, without delaying; and returns to replenish his resources in a ceaseless, indefatigable course, which never flags, night nor day. And you can form no idea how many workmen he has under his orders, all laboring without intermission, all requiring different things—not one of them pausing, even for a joke!—not even to say—"Wait a moment;"—they do not understand what waiting means: he must always keep giving, giving, giving. By and by we shall have a long account to give of this wonderful steward, whose name, be it known, if you have not already guessed it, is Blood.
It is he who, one fine day when he was making his round of the jaws, found those little germs I spoke of, awake and eager for work; and he began at once to start them with materials. He knew that phosphorus and lime were what they needed: he drew phosphorus and lime therefore out of his pockets,—and, to be very exact, some other little matters too,—but these were the most important; but I cannot stop to tell you everything at once.
Now, where did the blood obtain this phosphorus and lime?
I expected you to ask this, but if you want everything explained as we go along, we shall not get very far. In fact, if I answer all your questions I shall be letting out my secret too soon, and telling you the end of my story almost before it is begun.
So be it, however; perhaps you will feel more courage to go on, when you know where we are going.
The steward of a country-house distributes tiles, planks, paint, bricks, lime; but none of these things are his own, as you know; he has received them from his master: and, in the same way, our steward has nothing of his own: everything he distributes comes from the master of the house, and as I have already told you, this master is the stomach. As fast as the steward distributes, therefore, must the master renew the stores—and renew them all, for unless he does this, the work would stop. In proportion as the blood gives out on all sides the contents of his pockets, the stomach must replenish them, and fill them with everything necessary, or there would be a revolution in the house. Now, as there can be nothing in the stomach but what has got into it by the mouth, it behooves us to put into the mouth whatever is needed for the supply of our numerous workmen; and this is why we eat.
I perceive that I have plunged here into an explanation out of which I shall not easily extricate myself, for I can guess what you are going to say next. When you began to cut your teeth, you had eaten neither phosphorus nor lime, as nothing but milk had entered your mouth.
That is true. Neither then, nor since then, have you eaten those things, and what is more, I hope you never will. And yet both must have got into your mouth, for without them your teeth could never have grown. How are we to get out of this puzzle?
Suppose now, for a moment, that instead of phosphorus and lime, thelittle workmen in your jaws had asked the blood for sugar to make the teeth with. Fortunately this is only a supposition; otherwise I should be in great fear for the poor teeth: they would not last very long. Suppose, further, that instead of your eating the lump of sugar which was destined to turn into a tooth, your mamma had melted it in a glass of water, and had given it to you to drink; you could not say you had eaten sugar, and yet the sugar would really have got into your stomach, and there would be nothing very wonderful if the stomach had found it out and given it to the blood, and the blood had carried it off to the place where it was wanted. Now, allowing that the lump of sugar was very small, and the glass of water very large, the sugar might have passed without your perceiving it, and yet the tooth would have grown all the same, and without the help of a miracle.
And this is how it was. In the milk which you drank as a baby there were both phosphorus and lime, though in very small quantities. There were many other things besides; everything of course that the blood required for the use of its work-people, because at that time the stomach was only receiving milk, and yet all the work was going on as usual.
And therefore, my dear child, whenever in the course of our studies, you hear me describe such and such a thing as being within us, say quietly to yourself, "that also was in the milk which nourished me when I was a baby."
Of course, the same things are in what you eat now; only now they come in a form more difficult to deal with, and the labor of detaching them from the surrounding ingredients is much greater. The whole business indeed of this famous machine which we are studying consists in unfastening the links which hold things together, and in laying aside what is useful, to be sent to the blood divested of the refuse. The stomach was too feeble in your infancy to have encountered the work it has to do now. It is for this reason that God devised for the benefit of little children that excellent nourishment—milk—which contains, all ready for use, every ingredient the blood wants; and is almost, in fact, blood ready made.
Only think, my child, what you owe to her who gave you this nourishment! It was actually her blood she was giving you; her blood which entered into your veins, and which wrought within you in the wonderful way which I have been describing. Other people gave you sugar-plums, kisses, and toys; but she gave you the teeth which crunched the sugar-plums, the flesh of the rosy cheeks which got the kisses, and of the little hands which handled the toys. If ever you can forget this, you are ungrateful indeed!
Now, beware of going on to ask me how we know that there are so many sorts of things in milk, or I shall end by getting angry. Question after question; why, you might drive me in this way to the end of the world, and we should never reach the point we are aiming at. We have already traveled far away from the teeth, concerning which I wanted to talk to you at this time, but our lesson is nearly over and we have scarcely said a word about them! One cannot learn everything at once. Upon the point in question you must take my word; and as you may believe, I would not run the risk of being contradicted before you, by those who have authority on the subject.
Let it suffice you, for to-day, to have gained some idea of the manner in which the materials which constitute our bodies are manufactured within us. We have got at this by talking of the teeth; to-morrow, it may be the saliva, the next day something else. What I have now told you will be of use all the way through, and I do not regret the time we have given to the subject. If you have understood that well; the time has not been lost.
THE TEETH (continued.)
My thoughts return involuntarily to the subject I last explained to you, my dear child, and I find that I have a great deal to say about it still.
You see now, I hope, that we have something else to consult besides a dainty taste when we are eating; and that if we are to work to any good purpose we must think a little about this poor blood; who has so much to do, and who often finds himself so much at fault, when we send him nothing but barley-sugar and biscuits for his support. It is not with such stuff as that, as you may well imagine, that he can be enabled to answer satisfactorily to the constant demands of his little workmen, and we expose him to the risk of getting into disgrace with them, if we furnish him with no better provisions.
And who is the sufferer? Not I who am giving you this information, most certainly.
Now, when children hesitate about eating plain food, and fly from beef to rush at dessert, they act as a man would do who should begin to build by giving his workmen reeds instead of beams, and squares of gingerbread instead of bricks. A pretty house he would have of it; —just think!
On the contrary, what your mother asks you to eat, my dear little epicure, is sure to be something which contains the indispensable supplies for which your blood is craving; for people knew all about this by experience long before they could explain the why and the wherefore. But now that you are so much better informed than even the most learned men were a century ago, pouting and wry faces at table are no longer excusable, and I should be sadly ashamed of you if I should hear you continued to make them.
And this is what I was more particularly thinking of just now, when I took up my pen again. No doubt it is very amusing to be able to look clearly into one's frame, and see what goes on inside, but the amusement anything affords is the least important part of it; you have begun to find this out already, and you will find it out more and more every day. What seems to me one of the great advantages of the study we have begun together is, that at every step you take you will meet with the most practical and useful instruction, as well as the most unanswerable reasons for doing what your parents ask you to do every day.
To obey without knowing why is certainly possible, and may be done happily enough. But we obey more readily and easily when we understand the reason for doing so; and a duty which one can satisfy oneself about, forces itself upon one as a sort of necessity. And what can throw a stronger light on our duties than a thorough acquaintance with ourselves?
It is upwards of two thousand two hundred years ago (and that is not yesterday, you must own!) since one of the greatest minds of the world—Socrates—never forget that name—taught his disciples, as a foundation precept, this apparently simple maxim, "Know thyself." He meant this, it is true, in a much higher sense than we are aiming at in these conversations of ours, but his rule is so practical, that although you have only as yet taken a mere peep into one small corner of self-knowledge, you find, if I am not much mistaken, that your heart has beaten once or twice rather faster than it did before. Was I wrong, in saying from the beginning, that we become better as we grow in knowledge? Is it not true that you have felt more tenderly than ever towards her who nourished you with her milk, since I explained to you the value of milk; and that you have kissed your mother's hand all the more lovingly since you heard my history of the hand? To tell you the truth, if you had not done so, I should have been dissatisfied both with you and myself.
And wait! While we are talking thus, another thought has come into my head about hands and nurses, which I must tell you of.
There is something of the nurse, my child, in those who take the best fruits of their intellect and heart, and transform them, as it were, into milk, in order that your infant soul may receive a nourishment it will be able to digest without too much effort. In this way their very soul enters into you, and it is but fair that you should reward them as they deserve. Young as you are, too, you have a recompense in your power: one more acceptable even than Academic prizes—of which it is indispensable not to be too avaricious—you can give them your love.
Besides, it is not only hands but heads that are at work for you, and of these many more than you suppose; and your debt of gratitude is as much due to the one as to the other.
Perhaps my first letter may have led you to suppose that I was inclined to laugh at what I called learned men; and they are perhaps a little to blame for not thinking often enough about little girls; but nevertheless these men are of the greatest use to them in an indirect way. You owe them much, therefore, and without them could have known nothing of what I am teaching you. It is very grand for us, is it not, to know that there is phosphorus and lime in our teeth? But it took generations of learned men, and investigations and discoveries without end, and ages of laborious study, to extract from nature this secret which you have learnt in five minutes. And whatever others you may learn hereafter, remember that it is the same story with all. While profiting, therefore, at your ease, by all these conquests of science, I would have you hold in grateful recollection those who have gained them at so much cost to themselves: almost always at the expense of their fortune, sometimes at the peril of their lives.
There they are, observe, a little knot of men with no sort of outward pretension. They speak a language which scares children away. They weigh dirty little powders in apothecaries' scales; steep sheets of copper in acid-water; and watch air-bubbles passing through bent glass tubes, some of which are as dangerous as cannon balls. They scrape old bones, and slice scraps no bigger than a pin's head. They keep theireyes fixed for hours upon things they are examining through microscopes of a dozen glasses, and when you go to see what they are looking at, you find nothing at all. To see them at work, in what they call their laboratories, you would say that they were a set of madmen. But at the end, it is found, some fine day, that they have changed the face of the earth; have worked revolutions before which emperors and kings bow in respect; have enriched nations by millions at a time; have revealed to the human race, divine laws of which it had hitherto been ignorant; finally, have furnished the means of teaching little boys and girls some very curious things, which will make them more agreeable as well as reasonable. And this is a benefit not to be despised, since these children are destined one day to become fathers and mothers, and so to govern the next generation; and the better they themselves are instructed, the better this will be done.
But now let us go back to the poor teeth, whom we seem to have forgotten altogether. However, we knew very well that they would not run away meantime.
I told you before that it was their business to dress and prepare whatever was presented to them, but the reception they bestow is not one which would suit every body's taste, for it consists in being made mince-meat of And in order to do their work in the best way possible they divide their labor; some cut up, others tear, and others pound.
First, there are those flat teeth in front of the two jaws, just below the nose. Touch yours with the tip of your finger; you will find that they terminate in sharp-edged blades, like knives. These are called incisors, from the Latin word incidere, which means to cut, and it is with them we bite bread and apples, where the first business is to cut. It is with the same teeth that lazy little girls bite their thread, when they will not take the trouble to find their scissors; and, by the by, this is a very bad trick, because by rubbing them one against another in this manner we wear them out, and, as you will soon discover, worn-out teeth never grow again.
The next sort are those little pointed teeth, which come after the incisors, on each side of both jaws. You will easily find them; and if you press against them a little, you will feel their points. If we call the first set the knives of the mouth, we may call these its forks. They serve to pierce whatever requires to be torn, and they are called canine teeth, from the Latin word canis, a dog, because dogs make great use of them in tearing their food. They place their paws upon it, and plunging the canine teeth into it, pull off pieces by a jerk of the head. Look into the mouth of papa's dog: you will recognize these teeth by their rather curved points. They are longer than the rest, and are called fangs. I do not know, after all, why they have chosen to name these teeth canine, as all carnivorous animals have the same fangs, and in the lion, the tiger, and many other species, they are much more developed and sharper than in the dog. In cats they are like little nails. However, the name is given, and we cannot alter it.
The last teeth, which are placed at the back of the jaw, are called molars, from the Latin word mola, which means a millstone.
You must be prepared to meet with several Latin words as we go on; but never mind; this will give you the opportunity of learning a little Latin, and so of keeping your brother in order, if he ever looks down upon you because he is learning Latin at school. Formerly, all learned men wrote in Latin, and as they ruled supreme in all such subjects as those we are discussing, they gave to everything such names as they pleased, without consulting the public, who did not just then trouble their heads about the matter. Now they give Greek names, which can hardly be called an improvement; but if they ever wish to attract the attention of little girls they must translate their hard words into our own language.
To return to our grinders: they perform the same office as a miller's millstone; that is to say, they grind everything that comes in their way. These teeth have flat, square tops, with little inequalities on the surface, which you can feel the moment you lay your finger on them. These are the largest and strongest of the three sets, and with them we even crack nuts, when we prefer the risk of breaking our teeth to the trouble of looking for the nut-crackers!
Now, I will answer for it that you cannot explain to me why we always place what is hard to break between the molars, and never employ the incisors in the work? And yet everybody does this alike—from the child to the grown-up man—and all equally without thinking of what they are doing.
I will tell you the reason, however, if you will first tell me why, when you are going to snip off the tip of your thread (which offers very little resistance), you do it with the point of your scissors; whereas you put any tough thing which is likely to resist strongly (a match, for instance) close up to their hinge; particularly if you have no scruple about spoiling the scissors, by the way!
If you were a grown-up lad, and I were teaching you natural philosophy, I should have here a fine opportunity for explaining what is called the theory of the lever. But I think the theory of the lever would frighten you; so we must get out of the difficulty in some other way.
I find, however, that I have been joking so much as I went along, that I have but little space left, and feel quite ashamed of myself. We seem quite unlucky over these teeth.
I have already been scolded by people who are not altogether wrong in accusing me of losing my time in chattering, first of one thing and then of another. They complain that by thus nibbling at every blade of grass on the way-side we shall never get to the end of our journey; and there is some truth in what they say. Still, I will whisper to you in excuse that I thought we might play truant a little bit while we were on familiar ground, where naturally you were sure to feel a particular interest in everything. The hand, the tongue, the teeth—these are all old friends of yours—and I thought you would like to hear all about them. By-and-bye we shall be in the little black hole, and then we shall get on much more rapidly.
THE TEETH (continued).
I left off at the molars, which are the teeth one selects to crack nuts with; and if I remember rightly, we talked about different ways of cutting with scissors.
Let us look at the subject from a distance, that we may understand it more clearly. Let us imagine a horse drawing a heavy cart slowly along. Ask it to gallop, and it will answer, "With all my heart! but you must give me a lighter carriage to draw." And now fancy another flying over the ground with a gig behind it. Ask it to exchange the gig for the cart, and it will say, "Yes; but then I shall have to go slowly."
Whereby you see that with the same amount of strength to work with, one has the choice of two things: either of conquering a great resistance slowly, or a slight one quickly.
And it is partly on this account, dear child, that I teach you so gradually; for young heads, fresh to the work, are less easily drawn along than others, and have but a certain amount of strength.
Hitherto all has been clear as the day. Now take your scissors in your left hand; hold the lower ring of the handle firmly between your thumb and closed hand, so that the blade shall remain straight and immovable: then with your other hand cause the upper ring to go up and down, and watch the blade as it moves. The whole of it moves at once, and is put in motion by the same power—viz., your right hand. But the point makes a long circuit in the air, while the hinge end makes only a very little one—indeed, moves almost imperceptibly: and, as you may imagine, a different sort of effort is required from the motive power (your hand) according as resistance is made at the point or at the hinge. The point goes full gallop: it is the horse in the gig; the light work is for him. The hinge moves slowly; it is the cart-horse, and takes the heavy labor.
I hope I have made you understand this, for it explains the cracking of our nut, though you may not suspect it. Move your scissors once more in the same way. Now, you have before you the pattern of the two jaws on one side of your face, from the ear to the nose; the upper one, which never moves (as you may convince yourself by placing a finger on your upper lip when you either speak or eat), and the lower one which goes up and down. Two pairs of scissors set points to points give you the whole jaw. The incisors are at the points, they gallop up and down, and are worthless for doing hard work; the molars are at the hinges, and move slowly; and if anything tough has to be dealt with, it comes to them as a matter of course; hence they are the nutcrackers. You must own that it is pleasant to reflect thus upon what we are doing every day, and the next time you see a stonemason moving stones of twenty times his own weight with his iron bar, ask your papa to explain to you the principle of the lever. After what I have told you, you will understand it very readily, or at least enough of it to satisfy your mind.
But, besides this power of moving up and down, the lower jaw possesses another less obvious one, by means of which it goes from right to left. This is precisely what naughty children make use of when they grind their teeth: not that I mean this remark for you, for I have a better opinion of you than to suppose you do such things. Those who make such bad use of their jaws deserve to lose the power of ever moving them thus, and then they would find themselves sadly at a loss how to chew their bread—for their molars would be of but little service to them in such a case; as it is chiefly by this second action of the jaw that the food is pounded. Try to chew a bit of bread by only moving your jaw up and down, and you will soon tire of the attempt.
One word more to complete my description of the teeth: that portion of them which is in the jaw is called the root; and the incisors, which cannot work hard because, like the gig-horses, they have but little resisting power, possess only small and short roots; whereas the canines, whose duty it is to tear the food sideways, would run the risk of being dragged out and left sticking in the substances they are at work upon, if they were not well secured; these, therefore, have roots which go much deeper into the jaw, and in consequence of this they give us more pain than the others when the dentist extracts them: those famous eye-teeth, which so terrify people on such occasions, are the canines of the upper jaw, and lie, in fact, just below the eye.
The molars meanwhile would be in danger of being shaken in the sideway movement, while chewing: so they do as you would do if you were pushed aside. Now you would throw out your feet right and left in order to steady yourself, and thus the molars, which have always two roots, throw them out right and left for the same purpose. Some have three, some four, and they require no less for the business they have to do.
Above the root comes what is called the crown; that is the part of the tooth which is exposed to the air; the part which does the work, and which bears the brunt of all the rubbing. Now, however hard it may be, it would soon end in being worn out by all this fun if it were not covered by a still harder substance, which is called enamel. The enamel which forms the coating of china plates, and which you can easily distinguish by examining a broken plate, will give you a very exact idea of it. It is this enamel which gives the teeth the polish and brilliancy we so much admire, and it is desirable to be very careful of it, not out of vanity, though there is no objection to a little vanity on the subject, but because the enamel is the protector of the teeth, and when that is destroyed, you may say good- bye to the teeth themselves. All acids eat into the enamel, as vinegar or lemon-juice does into marble; and one of the best means of preserving this protecting armor of the teeth is never to eat the unripe windfalls of fruit, which I have seen unreasonable children pick up in orchards and devour so recklessly. They give sufficient warning, by their acidity, that they are not fit for food, and when this warning is neglected, they take their revenge by corroding the enamel of the teeth; not to speak of the disturbance which they afterwards cause in the poor stomach.
I said that without this coating of enamel, the teeth would be prematurely worn out, the reason of which is, that the teeth have not the property of growing again, as the nails and hair have. When those little germs of which I spoke when we began to describe the teeth, have finished their work, they perish and fall out, like masons who, when they have built the house, take their departure forever.
But the "forever" wants explanation. For such stern conditions would fall hard on very little children, who, not having come to their reason, cannot be expected to understand the great value of their teeth, and take all the care they need of them. So to them a second chance is given.
Your first teeth, the milk-teeth, as they are called, count for nothing: they are a kind of specimen, just to serve while you are very young.
When you are approaching what is called the age of reason, (and this word implies a great deal, my dear child,) the real teeth, the teeth which are to serve you for life, begin to whisper among themselves, "Now, here is a little girl who is becoming reasonable, and who will soon, or else never, be fit to take charge of her teeth." No sooner said than done: other masons set to work in other cells, placed under the first set, and as the permanent teeth keep growing and growing, they gradually push out the milk-teeth, which were only keeping their places ready for them till they came.
This is just your case at present, and you now understand your responsibility, and how necessary it is to preserve those good teeth which have placed so generous a confidence in your care of them, and which, once gone, can never be replaced.
You have no loss by the exchange; you had twenty-four at first, you will now have twenty-eight. Twenty-eight, did I say? nay, you will have thirty-two; but the last four will come later still. The last molars on each side, above and below, in both jaws, will not make their appearance till you are grown up. They are a fastidious and timid set, and will not run any risks; and they are called wisdom-teeth, because they do not appear till we are supposed to have arrived at years of discretion. Some people do not cut them before they are thirty, and you will agree that, if they have not become wise by that time, they have but a very poor chance of ever being so!
There is much more still to be said about the teeth; but I think I have told you quite enough to teach you the importance of these little bony possessions of yours, which children do not always value as they deserve, and whose safety they endanger as carelessly as if they had fresh supplies of them ready in their pockets. If so many skilful contrivances have been devised for enabling us to masticate our food properly, it is clear that this process is not an unimportant one. Those, therefore, who swallow a mouthful after two or three turns, forget that they are thereby forcing the stomach to do the work the teeth have neglected to do, and this is very bad economy, I can assure you. You will see hereafter, when we speak about animals, that by a marvellous compensation of nature, the power of the stomach is always great in proportion to the inefficiency of the teeth, and that by the same rule, it is weakest when the jaws are best furnished. Now, no jaw is more completely furnished than the human one; it is clear, then, that it should do its own work and not leave it to be done by those who are less able: and the little girl who, in order to finish her dinner more quickly, shirks the use of her teeth, and sends food, half chewed, into her stomach, is like a man who, having two servants, the one strong and vigorous, the other feeble and delicate, allows the first to dawdle at his ease, and puts all the hard work on the other. He would be very unjust in so doing, would he not? And as injustice always meets with its reward, his work is sure to be badly done.
Now, the work in question consists in reducing what we eat into a sort of pulp or liquid paste, from which the blood extracts at last whatever it requires. But the teeth may bite and tear the materials as they please, they can make nothing of them but a powder, which would never turn into a pulp, if during their labors they were not assisted by an indispensable auxiliary. To make pap for infants what do we add to the bread after it is cut in little bits? Without being a very clever cook, you will know that it is water which is wanted. And thus, to assist us in making pap for the blood, Providence has furnished us with a number of small spongy organs within the mouth, which are always filled with water. These are called salivary glands. This water oozes out from them of itself, on the least movement of the jaw, which presses upon the sponges as it goes up and down. The name of this water, as I need scarcely tell you, is saliva.
When I call it water, it is not merely from its resemblance; saliva is really pure water with a little albumen added. Do not be afraid of that word—it is not so alarming as it appears to be. It means simply the substance you know as the white of egg. There is also a little soda in the water, which you know is one of the ingredients of which soap is made. And this explains why the saliva becomes frothy, when the cheeks and tongue set it in motion in the mouth while we are talking; just as the whites of egg, or soapy water, become frothy when whipped up or beaten in a basin.
But the albumen and the soda have not been added to the saliva, in our case, merely to make it frothy; that would have been of very little use. They give to the water a greater power to dissolve the food into paste, and thus to begin that series of transformations by which it gradually becomes the fine red blood which shows itself in little drops at the tip of your finger when you have been using your needle awkwardly.
When once minced up by the teeth and moistened by the saliva, the food is reduced to a state of pulp, and having nothing further to do in the mouth, is ready to pass forward. But getting out of the mouth on its journey downwards is not so simple an affair as getting into it by the front door, as it did at first. Swallowing is in fact a complicated action, and not to be explained in half a dozen words, and I think we have already chatted enough for to-day. I only wish I may not have tired you out with these interminable teeth! But you may expect something quite new when I begin again.
You remember a certain door-keeper, or porter, of whom we have already spoken a good deal, who resides in the mouth—the sense of taste, I mean?
Well, it is a porter's business to sweep out the entrance to a house, and you may always recognize him in the courtyard by his broom.
And accordingly our porter too has a broom specially placed at his service, namely, the tongue; and an unrivalled broom it is—for it is self-acting, never wears out, and makes no dust—qualities we cannot succeed in obtaining in any brooms of our own manufacture.
When the time has come for the pounded mouthful (described in the last chapter) to travel forward (the teeth having properly prepared it), the broom begins its work; scouring all along the gums, twisting and turning right and left, backwards and forwards, up and down; picking up the least grains of the pulp which have been manufactured in the mouth; and as the heap increases, it makes itself into a shovel—another accomplishment one would scarcely have expected it to possess. What it gathers together thus, rolls by degrees on its surface into a ball, which at last finds itself fixed between the palate and the tongue in such a manner that it cannot escape; at which moment the tongue presses its tip against the upper front teeth, forms of itself an inclined plane, and—but stop! we are getting on too fast.
At the back of the mouth, (which is the antechamber, as we said before,) is a sort of lobby, separated from the mouth by a little fleshy tonguelet, suspended to the palate, exactly like those tapestry curtains which are sometimes hung between two rooms, under which one is enabled to pass, by just lifting them up.
If this lobby led only from the mouth to the stomach, the act of swallowing would be the simplest thing in the world; the tongue would be raised, the pounded ball would glide on, would pass under the curtain, and then good-bye to it. Unfortunately, however, the architect of the house seems to have economized his construction-apparatus here. The lobby serves two purposes; it is the passage from the mouth to the stomach, as well as from the nose to the lungs.
The air we breathe has its two separate doors there—one opening towards the nose, the other towards the lungs; through neither of which is any sort of food allowed to pass. But, as you may imagine, the food itself knows nothing of such spiteful restraints, and it is a matter of perfect indifference to it through which of the doors it passes. Not unlike a good many children who, though they are reasonable creatures, will push their way into places where they have been forbidden to go; and who can expect a pulpy food-ball to be more reasonable than a child? It was necessary, therefore, so to arrange matters that there should be no choice on the subject; that when the food-ball got into the lobby it should find no door open but its own, namely, that which led to the stomach. And that is exactly what is done.
You have not, perhaps, remarked that in the act of swallowing, something rises and contracts itself at the same moment in your throat, producing a kind of internal convulsion which jerks whatever is inside. People do not think about it when they are eating, because it is an involuntary action, and their attention is otherwise engaged.
But try to swallow when there is nothing in your mouth, and you will perceive what I mean at once.
Now, imagine our lobby at the back of the throat as a small closet, with a doorway in its wall, half-way up, the doorway being closed by a curtain. In the ceiling is a hole, which leads to the nose; in the floor two large tubes open out; the front one leading to the lungs, the one behind, to the stomach.
Now swallow, and I will tell you what happens. The curtain rises up and clings to the ceiling, and thus the passage to the nose is stopped up. The lung-tube rises along the wall, and hides itself under the door, contracting itself, and making itself quite small, as if it wished to leave plenty of room for the mouthful of food which is about to pass over it; and, for still greater security, at the very moment it rises, it pushes against a small trap-door which shuts up its mouth. No other road remains, therefore, but through the tube which leads to the stomach; the pulpy mouthful drops straight therein, without risk of mistake, and when it is once there, everything readjusts itself as before.
These are very ingenious contrivances, and I will venture to say that if we would but study the wonders of the marvellous and varied machinery which is constantly at work in our behalf within us, we should be much better employed than in learning things from which no practical good can be derived. Moreover, we should be ashamed to trust, like the lower animals, only to our instinct, (which, after all, is much less developed in us than in them,) for blindly escaping the thousand chances of destruction that beset a structure so fragile and delicate in its contrivances as the human body. Besides, it is not only our own machinery that is entrusted to us, we are liable to be responsible for that of others, whose development it is our duty to guard and watch; and how can we do this with a safe conscience, if we are ignorant of the construction, the action, the laws of all sorts which the great Artificer has, so to speak, made use of in forming our bodies?
When you, in your turn, are a mother, you dear little rogue, who sit there opening wide your bright eyes, and not comprehending a word of what I am saying, you will be glad that you were taught when you were little, how your own little girl ought to be managed. You will find a hundred opportunities of making good use, in her behalf, of what you and I are learning together, and in the meantime there is no reason why you should not yourself profit by the knowledge you have gained.
I am quite sure, for instance, that in repeating to your child the simple rule of politeness, with which everybody is acquainted, "Never talk when you are eating," you will be very careful to add, "and especially when you are swallowing," for reasons I am about to detail.
When we want to speak we have to drive the air from the lungs into the mouth, and our words are sounds produced by this air as it passes through. This is the reason why I advise you to go on gently, and make the proper stops in reading aloud: to take breath, in fact, as it is called; otherwise, breath would all at once fail you, and you would be obliged to stop short in the middle of a sentence and wait like a simpleton till you had refilled the lungs with air by breathing. It was for this purpose, also, and not for mere economy's sake, as you may have thought, that the little cross-road of four doors has been placed at the back of the mouth, enabling it to communicate at pleasure with either the lungs or the stomach. It is a dangerous passage for food-parcels making their way to the stomach; but if you could substitute for it, as it may have occurred to you to do lately, a simple tube going directly to the stomach,—behold! you would find yourself dumb;—a serious misfortune, eh? for a little girl! But come, I am quizzing too much, so console yourself. I know many grown-up people who would be at least as sorry as yourself.
To return to our subject. We have said that, in order to guard against accidents, the lung-tube is closed at the moment we are about to swallow. But if by any unlucky chance the air is coming up from the lungs at the same moment, it must have a free passage. Its tube cannot help returning to its place; the little trap-door which shuts up the opening opens whether or no, and then adieu to all the precautions of good Mother Nature! The mouthful when it drops, falls outside of its proper tube—that is to say, into the other, which is exactly in front of it, and we find that we have swallowed the wrong way.
You know what happens in such a case. You cough and cough till you are torn to pieces, till you grow scarlet, or even blue in the face; till you lose your breath; till your body trembles; till your eyes start out of their sockets. Let who will be there, there is no resource but to hide your face in your handkerchief. The tube, which was only made for the passage of air, on finding an intruder forcing an entrance, does its utmost to drive it back through the door. Then the lungs, which would be destroyed by its getting to them, come to the assistance of the faithful servant who is struggling for their protection: they agitate themselves violently, and send forth gusts of air which drive all before them. Thence arises the cough, and by this means at last the enemy is thrust out of the mouth, like dust before the wind. And it is only when the passages are cleared that the storm subsides. But the commotion is no laughing matter, I assure you; for if one had swallowed a little too far the wrong way, or if the substance swallowed had been too heavy for the air-tube, aided by the lungs, to eject within a certain time, death would have ensued: instances of which are by no means unknown. Nature does nothing in vain; this is no case of a man frightened by a mouse. When you find your whole being concentrating its efforts to one point, and betraying such distress, at an accident apparently so trifling, you may be sure there is danger, and real danger too; and if you doubt it, that makes no difference—happily for you.
Now you have learned why little girls should not attempt to talk and swallow at the same time, and, I may add, still less laugh; for laughingis a kind of somersault, performed by the lungs, and is always accompanied by the ejectment of a great deal more breath than is necessary in speaking, so that the jerks it occasions derange still more the wise provisions made to protect life whenever we swallow anything, and therefore we are more apt to swallow the wrong way while laughing than while speaking.
Need I say that we ought equally to guard against making others laugh or talk; or exciting, or frightening them, while they are swallowing; in short, avoid doing anything to create a sudden shock which might suddenly force the air out of their lungs, and cause them in the same manner to swallow the wrong way? Politeness requires this from us, and what I have now said will fix the lesson still more strongly on your mind. What would become of you if you were to see a person die in your presence in consequence of some foolish joke, however apparently innocent?
Not to conclude with so painful a picture, I will, before we part, give you the right names of the curtain, the lobby or closet, and the tubes of which we have been speaking.
The curtain is called the Soft Palate.
The lobby, the Pharynx.
The tube which leads to the stomach, the Aesophagus.
The tube leading to the lungs, the Larynx.
The opening of this tube is the Glottis, and the little trap-door which closes it when one swallows, is the Epiglottis.