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.

But, further:

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,