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.