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 gla.s.s 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 gla.s.s of water very large, the sugar might have pa.s.sed 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 quant.i.ties. 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 G.o.d 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 const.i.tute 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.

LETTER V.

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 amus.e.m.e.nt 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 grat.i.tude 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 pa.s.sing through bent gla.s.s tubes, some of which are as dangerous as cannon b.a.l.l.s. They sc.r.a.pe old bones, and slice sc.r.a.ps no bigger than a pin's head. They keep theireyes fixed for hours upon things they are examining through microscopes of a dozen gla.s.ses, 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 s.p.a.ce 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 gra.s.s 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.