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THE FAIRY-LAND OF SCIENCE

'^y.

"us^*-

THE

Fairy-Land of Science

r»^*

ARABELLA B.'' BUCKLEY ."

AUTHOR OF A SHORT HISTuRY OF XATIRAI. SMENCE,
BOTANICAL TABLES FOR YOUNG STIDENTS, ETC.

/ . ', '• .»

For th<y sexdJAibsr yci tne tales we toI<^ them -
ArcuDQ iK^yt^alth^ of fairies, long agb, *"

When they'lD^p<l still in fancy to beholu tliem
Quick dancing earthward in the feathery snow.

" But now the young and fresh imagination

FLo4a SMUjes of their presence ever>-where, . . *• '

'^ *

And peoples-with a new and bright creati<^n
The^tfear blue chambers of the sunny £ir '^ '
- ■ •' ,'^ - Folk Ld^;

«. ♦ .*,

n^LVSTRATED

* J

• «

NEW-

f.^ C0LUV:3US B?A\CH, f

7:i^

^ "

THE NtV/ .:RK

ASTOf^, LENOX AND
TILDEN FOV.ND'iT 'ONS

19*4 L

^^t). APPLETON AIfl5*JtOMPANY,

••

• ••

•V.-.-

# • »< •

• • •*• *> •

w • • *■ *

• • • •

• •••

. . . • •. •• •

• • • •• •

■3"

ST) 6^ Scf\

PROPERTY OF THE
CITY OF NEW Vu:iK

PUBLISHERS' NOTE.

The publishers of the Fair>-land of Science, v.'ith
the assistance of the talented authoress, have consider-
ably extended the original volume, adding to it more
or less extended notices of the latest scientific discov-
eries in the departments treated, and amplifWng \\4th
fuller detail such portions as have growTi in impor-
tance and interest since the first publication of the
work more than twenty years ago. A careful revision
has, as far as practicable, eliminated all errors and also
all words which, on account of their almost exclusive
use in England, are not likely to be easily understood
by children in the United States. American instead
of English examples are given to illustrate statements
of general scientific truths, and, in fact, the whole
letter-press has been carefully and thoroughly edited
in the endeavour to adapt it to the use and enjoy-
ment of our children at home.

The work has also been largely re-illustrated. It is
now offered in the belief that the clear and re

Vi PUBLISHERS' NOTE.

Style, the untechnical language, and ingenious fancy
of its authoress that first made the Fairy-land of Sci-
ence acceptable to its readers, will be no less worthy
of appreciation when extended to embrace recent de-
velopments of knowledge and adjusted to meet the
special requirements of the American public.

February ^ i8gg.

PREFACE.

The Ten Lectures of which this volume is com-
posed were delivered in the spring of 1878, in St.
John's Wood, to a large audience of children and
their friends, and at their conclusion I was asked by
many of those present to publish them for a child's
reading book.

At first I hesitated, feeling that written words can
never produce the same effect as viva-voce delivery.
But the majority of my juvenile hearers were evidently
so deeply interested that I am encouraged to think
that the present work may be a source of pleasure
to a wider circle of young people, and at the same
time awaken in them a love of nature and of the study
of science.

The Lectures were entirelv rewritten from the
short notes used when they were delivered. With
the exception of the first of the series, none of them
have any pretensions to originality, their object being
merely to explain well-known natural facts in sim^l^

THE FAIRY- LAND OF SCIENCE

!^'

2 THE FAIRY-LAND OF SCIENCE.

poetry and imagination. But I thoroughly believe
myself, and hope to prove to you, that science is full
of beautiful pictures, of real poetry, and of wonder-
working fairies; and what is more, I promise you
they shall be true fairies, whom you will love just
as much when you are old and greyheaded as when
you are young; for you will be able to call them
up wherever you wander by land or by sea, through
meadow or through wood, through water or through
air; and though they themselves will always remain
invisible, yet you will see their wonderful power at
work everywhere around you.

Let us first see for a moment what kind of tales

science has to tell, and how far they are equal to the

old fairy tales we all know so well. Who does not

remember the tale of the Sleeping Beauty in the

Wood, and how under the spell of the angry fairy

the maiden pricked herself with the spindle and slept

a hundred years? How the horses in the stall, the

dogs in the court-yard, the doves on the roof, the cook

who was boxing the scullery boy's ears in the kitchen,

and the king and queen with all their courtiers in the

hall remained spell-bound, while a thick hedge grew

up all round the castle and all within was still as

- "death. \But when the hundred years had passed the

{'\ valiant prince came, the thorny hedge opened before

C^ \him bearitig>bfiautiful flowers; and he, entering the

" castle, reached /die.room where the princess lay, and

with one sweet kiss", raised her and all around her to

life again.

Can science bring any tale to match this?

Tell me, is there .anything in this world more busy

THE FAIRY-LAND OF SCIENCE. 3

and active than water, as it rushes along in the swift
brook, or dashes over the stones, or spouts up in the
fountain, or trickles down from the roof, or shakes
itself into ripples on the surface of the pond as the
wind blows over it? But have you never seen this
water spell-bound and motionless? Look out of the
window some cold frosty morning in winter, at the
little brook which yesterday was flowing gently past
the house, and see how still it lies, with the stones
over which it was dashing now held tightly in its icy
grasp. Notice the wind-ripples on the pond; they
have become fixed and motionless. Look up at the
roof of the house. There, instead of living doves
merely charmed to sleep, we have running water
caught in the very act of falling and turned into
transparent icicles, decorating the eaves with a beau-
tiful crystal fringe. On every tree and bush you will
catch the water-drops napping, in the form of tiny
crystals; while the fountain looks like a tree of glass
with long down-hanging pointed leaves. Even the
damp of your own breath lies rigid and still on the
window-pane frozen into delicate patterns like fern-
leaves of ice.

All this water was yesterday flowing busily, or
falling drop by drop, or floating invisibly in the air;
now it is all caught and spell-bound — by whom?
By the enchantments of the frost-giant who holds it
fast in his grip and will not let it go.

But wait awhile, the deliverer is coming. In a
few weeks or days, or it may be in a few hours, the
brave sun will shine down ; the dull-grey, leaden sky
will melt before him, as the hedge gave way before

4 THE FAIRY-LAND OF SCIENCE.

the prince in the fairy tale, and when the sunbeam
gently kisses the frozen water it will be set free.
Then the brook will flow rippling on again ; the frost-
drops will be shaken down from the trees, the icicles
fall from the roof, the moisture trickle down the win-
dow-pane, and in the bright, warm sunshine all will
be alive again.

Is not this a fairy tale of nature? and such as these
it is which science tells.

Again, who has not heard of Catskin, who came
out of a hollow tree, bringing a walnut containing
three beautiful dresses — the first glowing as the sun,
the second pale and beautiful as the moon, the third
spangled like the star-lit sky, and each so fine and
delicate that all three could be packed in a nut ? But
science can tell of shells so tiny that a whole group
of them, will lie on the point of a pin, and many
thousands be packed into a walnut-shell; and each
one of these tiny structures is not the mere dress but
the home of a living animal. It is a tiny, tiny shell-
palace made of the most delicate lacework, each pat-
tern being more beautiful than the last ; and what .is
more, the minute creature that lives in it has built it
out of the foam of the sea, though he hiniself is noth-
ing more than a drop of jelly.

Lastly, any one who has read the Wonderful Trav-
elers must recollect the man whose sight was so
keen that he could hit the eye of a fly sitting on
a tree two miles away. But tell me, can you see gas
before it is lighted, even when it is coming out of the
gas-jet close to your eyes? Yet, if you learn to use
that wonderful instrument the spectroscope, it wi!^

THE FAIRY'LAXD OF SCIKXCE. 5

enable you to tell one kind of gas from anolhcr* even
when thev are both ninetv-one millions of miles uwrtv
on the face of the sun: nav more* it will roail for vou
the nature of the different gases in iho far distant
stars, billions of miles awav. and actually toll vou
whether vou could find there anv of the same utotuls
which we have on the earth.

We might find hundreds of such fairy tales in the
domain of science, but these three will serve as ex-
amples, and we must pass on to make the aoijuaint-
ance of the science-fairies themselves, and see if thev
are as real as our old friends.

Tell me, why do you love fairy-huul? what is its
charm? Is it not that things happen so suddenly,
so mysteriously, and without man having anything to
do with it? In fairy-land, flowers blow, houses spring
up like Aladdin's palace in a single night, an<l people
are carried hundreds of miles in an instant by the
touch of a fairy wand.

And then this land is not some distant eoinitrv
to which zue can never hope to travel. It is here
in the midst of us, only our eyes nnist be opened or
we cannot see it. Ariel and Puck did nol live In
some unknown region. C)n the contrary, Ariel'H
song is

"Where the bee sucks, ihcrt! Huck I ;
In a cowslip's bell I lie ;
There I couch when owIh do cry.
On the bat's back I do fly,
After summer, merrily."

The peasant falls asleep some evening in a wood,
a.-d his eyes are opened by a fairy wan<l, so that he

6 THE FAIRY-LAND OF SCIENCE.

sees the little goblins and imps dancing round him on
the green sward, sitting on mushrooms, or in the
heads of the flowers, drinking out of acorn-cups,
fighting with blades of grass, and riding on grass-
hoppers.

So, too, the gallant knight, riding to save some poor
oppressed maiden, dashes across the foaming torrent ;
and just in the middle, as he is being swept away,
his eyes are opened, and he sees fairy water-nymphs
soothing his terrified horse and guiding him gently to
the opposite shore. They are close at hand, these
sprites, to the simple peasant or the gallant knight, or
to anyone who has the gift of the fairies and can see
them. But the man who scoffs at them, and does not
believe in them or care for them, he nroer sees them.
Only now and then they play him an ugly trick, lead-
ing him into some treacherous bog and leaving him
to get out as he may.

Now, exactly all this which is true of the fairies of
our childhood is true too of the fairies of science.
There are forces around us, and among us, which I
shall ask you to allow me to call fairies, and these are
ten thousand times more wonderful, more magical,
and more beautiful in their work, than those of the old
fairy tales. They, too, are invisible, and many people
live and die without ever seeing them or caring to see
them. These people go about with their eyes shut,
either because they do not open them, or because no
one has taught them how to see. They fret and worry
over their own little work and their own petty troubles,
and do not know how to rest and refresh themselves,

THE FAIRY-LAND OF SCIEXCE. 7

by letting the fairies open their eyes and show them
the calm sweet pictures of nature. They are like
Peter Bell of whom Wordsworth wrote : —

••A primrose by a river's brim
A yellow primrose was to him.
And it was nothing more."

But we will not be like these, we will open our
eyes, and ask, " What are these forces or fairies, and
how can we see them ? "

Just go out into the country, and sit down quietly
and watch nature at work. Listen to the wind as
it blows, look at the clouds rolling overhead, and the
waves rippling on the pond at your feet. Hearken
to the brook as it flows by, watch the flower-buds
opening one by one, and then ask yourself, ** How
is all this done?" Go out in the evening and see
the dew gather drop by drop upon the grass, or
trace the delicate hoar-frost crystals which bespangle
every blade on a winter's morning. Look at the
vivid flashes of lightning in a storm, and listen to the
pealing thunder : and then tell me, by what machinery
is all this wonderful work done? Man does none of
it, neither could he stop it if he were to try ; for it
is all the work of those invisible forces or fairies whose
acquaintance I wish you to make. Day and night,
summer and winter, storm or calm, these fairies are at
work, and we may hear them and know them, and
make friends of them if we will.

There is only one gift we must have before we can
learn to know them — we must have imagination, I
do not mean mere fancy, which creates unreal images

8 THE FAIRY-LAND OF SCIENCE.

and impossible monsters, but imagination, the power
of making pictures or images in our mind, of that
which is, though it is invisible to us. Most children
have this glorious gift, and love to picture to them-
selves all that is told them, and to hear the same tale
over and over again till they see every bit of it as if it
were real. This is why they are sure to love science
if its tales are told them aright; and I, for one, hope
the day may never come when we may lose that child-
ish clearness of vision, which enables us through the
temporal things which are seen, to realize those eternal
truths which are unseen.

If you have this gift of imagination come with me,
and in these lectures we will look for the invisible
fairies of nature.

Watch a shower of rain. Where do the drops come
from? and why are they round, or rather sHghtly
oval? In our fourth lecture we shall see that the
little particles of water of which the rarn-drops are
made, were held apart and invisible in the air by heat,
one of the most wonderful of our forces * or fairies,
till the cold wind passed by and chilled the air. Then,
when there was no longer so much heat, another
invisible force, cohesion, which is always ready and
waiting, seized on the tiny particles at once, and
locked them together in a drop, the closest form in
which they could lie. Then as the drops became

* I am quite aware of the danger incurred by using this word
" force," especially in the plural ; and how even the most mod-
est little book may suffer at the hands of scientific purists by
employing it rashly. As, however, the better term "energy"
would not serve here, I hope I may be forgiven for retaining
the much-abused term, especially as I sin in very good company.

THE FAIRY-LAND OF SCIENCE. q

larger and larger they fell into the grasp of another
invisible force, gravitation, which dragged them down
to the earth, drop by drop, till they made a shower of
rain. Pause for a moment and think. You have
surely heard of gravitation, by which the sun holds
the earth and the planets, and keeps them moving
round him in regular order? Well, it is this same
gravitation which is at work also whenever a shower
of rain falls to the earth. Who can say that he is not
a great invisible giant, ahvays silently and invisibly
toiling in great things and small whether we wake or
sleep ?

Now the shower is over, the sun comes out, and the
ground is soon as dry as though no rain had fallen.
Tell me, what has become of the rain-drops ? Part no
doubt have sunk into the ground, and as for the rest,
why you will say the sun has dried them up. Yes,
but how? The sun is more than ninetv-two millions
of miles away; how has he touched the rain-drops?
Have you ever heard that invisible waves are travelling
every second over the space between the sun and us ?
We shall see in the next lecture how these waves are
the sun*s messengers to the earth, and how they tear
asunder the rain-drops on the ground, scattering them
in tiny particles too small for us to see, and bearing
them away to the clouds. Here are more invisible
fairies working every moment around you, and you
cannot even look out of the window without seeing
the work they are doing.

If, however, the day is cold and frosty, the water
does not fall in a shower of rain ; it comes down in the
shape of noiseless snow. Go out after such a snow-

lO THE FAIRY-LAND OF SCIENCE.

shower, on a calm day, and look at some of the flakes
which have fallen; you will see, if you choose good
specimens, that they are not mere masses of frozen
water, but that each one is a beautiful six-pointed
crystal star. How have these crystals been built up?
What power has been at work arranging their delicate
forms? In the fourth lecture we shall see that up in
the clouds another of our invisible fairies, which, for
want of a better name, we call the " force of crystal-
lization," has caught hold of the tiny particles of
water before " cohesion " had made them into round
drops, and there silently but rapidly, has moulded
them into those delicate crystal stars known as " snow-
flakes."

And now, suppose that this snow-shower has fallen
early in February; turn aside for a moment from
examining the flakes, and clear the newly-fallen snow
from off the flower-bed on the lawn. What is this
little green tip peeping up out of the ground under
the snowy covering? It is a young snowdrop plant.
Can you tell me why it grows? where it finds its food?
what makes it spread out its leaves and add to its stalk
day by day ? What fairies are at work here ?

First there is the hidden fairy " life," and of her
even our wisest men know but little. But they know
something of her way of working, and in Lecture VII
we shall learn how the invisible fairy sunbeams have
been busy here also; how last year's snowdrop plant
caught them and stored them up in its bulb, and how
now in the spring, as soon as warmth and moisture
creep down into the earth, these little imprisoned sun-
waves begin to be active, stirring up the matter in

THE FAIRY'LAXD OF SCIEXCE. u

the bulb, and making it swell and burst upward till it
sends out a little shoot through the surface of the
soil. Then the sun-waves above-ground take up the
work, and form green granules in the tiny leaves.
helping them to take food out of the air, while the
little rootlets below are drinking water out of the
ground. The invisible life and invisible sunbeams are
busy here, setting actively to work another fairx*, the
force of " chemical attraction," and so the little snow-
drop plant grows and blossoms, without any help from
you or me.

One picture more, and then I hope you will believe
in my fairies. From the cold garden, you run into the
house, and find the fire laid indeed in the gjate, but
the wood dead and the coal black, waiting to be
lighted. You strike a match, and soon there is a
blazing fire. Where does the heat come from ? Why
does the coal burn and give out a glowing light ? Have
you not read of gnomes buried down deep in the earth,
in mines, and held fast there till some fairv wand
has released them, and allowed them to come to earth
again? Well, thousands and millions of years ago,
this coal was plants, and like the snowdrop in the
garden of to-day, caught the sunbeams and worked
them into leaves. Then the plants died and were
buried deep in-the earth and the sunbeams with them ;
and like the gnomes they lay imprisoned till the coal
was dug out by the miners, and brought to your grate ;
and just now you yourself took hold of the fairy
wand which was to release them. You struck a
match, and its atoms clashing with atoms of oxygen
in the air, set the invisible fairies' " heat " and " chemi-

12 THE FAIRY-LAND OF SCIENCE.

cal attraction " to work, and they were soon busy
within the wood and the coal causing their atoms
too to clash; and the sunbeams, so long imprisoned,
leapt into flame. Then you spread out your hands
and cried, " Oh, how nice and warm ! " and little
thought that you were warming yourself with the sun-
beams of ages and ages ago.

This is no fancy tale; it is literally true, as we
shall see in Lecture VIII, that the warmth of a coal
fire could not exist if the plants of long ago had not
used the sunbeams to make their leaves, holding them
ready to give up their warmth again whenever those
crushed leaves are consumed.

Now, do you believe in, and care for, my fairy-land ?
Can you see in your imagination fairy Cohesion eyer
ready to lock atoms together when they draw very
near to each other: or fairy Gravitation dragging
rain-drops down to the earth : or the fairy of Crystalli-
zation building up the snow-flakes in the clouds ? Can
you picture tiny sunbeam-waves of light and heat
travelling from the sun to the earth ? Do you care to
know how another strange fairy, " Electricity/' flings
the lightning across the sky and causes the rumbling
thunder ? Would you like to learn how the sun makes
pictures of the world on which he shines, so that we
can carry about with us photographs or sun-pictures
of all the beautiful scenery of the earth? And have
you any curiosity about " Chemical action" which
works such wonders in air, and land, and sea ? If you
ha e any wish to know and make friends of these in-
visible forces, the next question is

THE FAIRY-LAND OF SCIENCE.

How are you to enter the fairy-land of science ?

There is but one way. Like the knight or peasant
in the fairy tales, you must open your eyes. There is
no lack of objects, everything around you will tell
some history if touched with the fairy wand of imag-
ination. I have often thought, when seeing some
sickly child drawn along the street, lying on its back
while other children romp and play, how much hap-
piness might be given to sick children at home or in
hospitals, if only they were told the stories which lie
hidden in the things around them. They need not
even move from their beds, for sunbeams can fall on
them there, and in a sunbeam there are stories enough
to occupy a month. The fire in the grate, the lamp
by the bedside, the water in the tumbler, the fly on
the ceiling above, the flower in the vase on the table,
anything, everything, has its history, and can reveal
to us nature^s invisible fairies.

Only you must wish to see them. If you go
through the world looking upon everything only as
so much to eat, to drink, and to use, you will never
see the fairies of science. But if you ask yourself why
things happen, and how the great God above us has
made and governs this world of ours ; if you listen to
the wind, and care to learn why it blows ; if you ask
the little flower why it opens in the sunshine and
closes in the storm; and if when you find questions
you cannot answer, you will take the trouble to hunt
out in books, or make experiments, to solve your own
questions, then you will learn to know and love those
fairies.

Mind, I do not advise you to be constantly asking

THE FAIRY-LAND OF SCIENCE.

questions of other people ; for often a question quickly
answered is quickly forgotten, but a difficulty really
hunted down is a triumph for ever. For example,
if you ask why the rain dries up from the ground,
most likely you will be answered that " the sun dries
it," and you will rest satisfied with the sound of the
words. But if you hold a wet handkerchief before
the fire and see the damp rising out of it, then you
have some real idea how moisture may be drawn up
by heat from the earth.

A little foreign niece of mine, only four years old,
who could not speak English plainly, was standing
one morning near the bedroom window and she no-
ticed the damp trickling down the window-pane.
" Auntie," she said, " what for it rain inside ? " It was
quite useless to explain to her in words, how our breath
had condensed into drops of water upon the cold glass ;
but I wiped the pane clear, and breathed on it several
times. When new drops were formed, I said, " Cissy
and auntie have done like this all night in the room."
She nodded her little head and amused herself for a
long time breathing on the window-pane and watching
the tiny drops; and about a month later, when we
were travelling back to Italy, I saw her following the
drops on the carriage window with her little finger, and
heard her say quietly to herself, " Cissy and auntie
made you." Had not even this little child some real
picture in her mind of invisible water coming from her
mouth, and making drops upon the window-pane ?

Then again, you must learn something of the lan-
guage of science. If you travel in a country with

THE FAIRY^LAND OF SCIENCE,

no knowledge of its language, you can learn very little
about it: and in the same way if you are to go to
books to find answers to your questions, you must
know something of the language they speak. You
need not learn hard scientific names, for the best
books have the fewest of these, but you must really
understand what is meant by ordinary words.

For example, how few people can really explain
the difference between a solids such as the wood of the
table ; a liquid, as water ; and a gas, such as I can let
of? from this gas-jet by turning the tap. And yet
any child can make a picture of this in his mind if
only it has been properly put before him.

All matter in the world is made up of minute
parts or particles ; in a solid these particles are locked
together so tightly that you must tear them forcibly
apart if you wish to alter the shape of the solid
piece. If I break or bend this wood I have to force
the particles to move round each other, and I have
great difficulty in doing it. But in a liquid, though
the particles are still held together, they do not cling
so tightly, but are able to roll or glide round each
other, so that when you pour water out of a cup on
to a table, it loses its cuplike shape and spreads itself
out flat. Lastly, in a gas the particles are no longer
held together at all, but they try to fly away from
each other; and unless you shut a gas in tightly
and safely, it will soon have spread all over the
room.

A solid, therefore, will retain the same bulk and
shape unless you forcibly alter it; a liquid will retain
the same bulk, but not the same shape if it be left

16 THE FAIRY-LAND OF SCIENCE.

free; a gas will not retain either the same bulk or
the same shape, but will spread over as large a space
as it can find wherever it can penetrate. Such simple
things as these you must learn from books and by ex-
periment.

Then you must understand what is meant by
chemical attraction; and though I can explain this
roughly here, you will have to make many interesting
experiments before you will really learn to know this
wonderful fairy power. If I dissolve sugar in water,
though it disappears it still remains sugar, and does
not join itself to the water. I have only to let the
cup stand till the water dries, and the sugar will re-
main at the bottom. There has been no chemical at-
traction here.

But now I will put something else in water which
will call up the fairy power. Here is a little piece of
the metal potassium, one
of the simple substances
of the earth; that is to
say, we can not split it
up into other substances,
wherever we find it, it is
always the same. Now if
I put this piece of potas-
sium on the water it does
not disappear quietly like the sugar. See how it rolls
round and round, fizzing violently, with a blue fiame
burning round it, and at last goes ofT with a pop.
What has been happening here?
You must first know that water is made of two
substances, hydrogen and oxygen, and these are not

THE FAIRY-LAND OF SCIENCE. 17

merely held together, but are joined so completely
that they have lost themselves and have become
water; and each atom of water is made of two atoms
of hydrogen and one of oxygen.

Now the metal potassium is devotedly fond of
oxygen, and the moment I threw it on the water it
called the fairy " chemical attraction " to help it, and
dragged the atoms of oxygen out of the water and
joined them to itself. In doing this it also caught part
of the hydrogen, but only half, and so the rest was
left out in the cold. No, not in the cold! for the
potassium and oxygen made such a great heat in
clashing together that the rest of the hydrogen
became very hot indeed, and sprang into the air to
find some other companion to make up for what it
had lost. Here it found some free oxygen floating
about, and it seized upon it so violently, that they
made a burning flame, while the potassium with its
newly found oxygen and hydrogen sank down quietly
into the water as potash. And so you see we . have
got quite a new substance potash in the basin ; made
with a great deal of fuss by chemical attraction drawing
different atoms together.

When you can really picture this power to yourself
it will help you very much to understand what you
read and observe about nature.

Next, as plants grow around you on every side,
and are of so much importance in the world, you must
also learn something of the names of the different
parts of a flower, so that you may understand those
books which explain how a plant grows and lives and
forms its seeds. You must also know the common

1 8 THE FAIRY-LAND OF SCIENCE.

names of the parts of an animal, and of your own
body, so that you may be interested in understand-
ing the use of the different organs ; how you breathe,
and how your blood flows; how one animal walks,
another flies, and another swims. Then you must
learn something of the various parts of the world, so
that you may know what is meant by a river, a plain,
a valley, or a delta. All these things are not difficult,
you can learn them pleasantly from simple books on
physics, chemistry, botany, physiology, and physical
geography; and when you understand a few plain
scientific terms, then all by yourself, if you will open
your eyes and ears, you may wander happily in the
fairy-land of science. Then wherever you go you
will find

** Tongues in trees, books in the running brooks,
Sermons in stones, and good in everything.'*

And now we come to the last part of our subject.
When you have reached and entered the gates of
science, how are you to use and enjoy this new and
beautiful land ?

This is a very important question, for you may
make a twofold use of it. If you are only ambitious
to shine in the world, you may use it chiefly to get
prizes, to be at the head of your class, or to pass in
examinations; but if you also enjoy discovering its
secrets, and desire to learn more and more of nature,
and to revel in dreams of its beauty, then you will study
science for its own sake as well. Now it is a good
thing to win prizes and be at the head of your class,
for it shows that you are industrious; it is a good

THE FAIRY-LAND OF SCIENCE. 19

thing to pass well in examinations, for it shows that
you are accurate; but if you study science for this
reason ofdy, do not complain if you find it dull, and
dry, and hard to master. You may learn a great deal
that is useful, and nature will answer you truthfully
if you ask your questions accurately, but she will give
you dry facts, just such as you ask for. If you do
not love her for herself she will never take you to her
heart.

This is the reason why so many people complain
that science is dry and uninteresting. They forget that
though it is necessary to learn accurately, for so only
we can arrive at truth, it is equally necessary to love
knowledge and make it lovely to those who learn, and
to do this we must get at the spirit which lies under
the facts. What child which loves its mother's face
is content to know only that she has brown eyes, a
straight nose, a small mouth, and hair arranged in
such and such a manner? No, it knows that its
mother has the sweetest smile of any woman living;
that her eyes are loving, her kiss is sweet, and that
when she 4ooks grave, then something is wrong which
must be put right. And it is in this way that those
who wish to enjoy the fairy-land of science must love
nature.

It is well to know that when a piece of potassium
is thrown on water the change which takes place is
expressed by the formula K + HgO^KHO + H.
But it is better still to have a mental picture of the
tiny atoms clasping each other, and mingling so as to
make a new substance, and to feel how wonderful are
the many changing forms of nature. It is useful '

I
I

20 THE FAIRY-LAND OF SCIENCE.

be able to classify a flower and to know that the
buttercup belongs to the Family Ranunculacea^, with
petals free and definite, slaiiutis hypogynous and iii-
deHnite, pistil apocarpous. But it is far sweeter to
learn about the life of the little plant, to understand
why its pecuhar flower is useful to it, and how it
ieeds itst-if, and makes its seed. No one can love dry
facts; we must clothe
ihem with real mean-
ing and love the
truths they tell, if we
wish to enjoy science.
Let us take an ex-
ample to show this.
I have here a branch
of white coral, a beau-
tiful, delicate piece of
nature's work. We
will begin by copy-
ing a description of
it from one of those
I class - books which
suppose children to
learn words like par-
rots, and to repeat
them with just as little
nderstanding.

" Coral is formed
' by an animal belong-
ing to the kingdom of
Radiates, sub-kinftdom Polypes. The soft body of
the animal is attached to a support, the mouth open-

THE FAIRY-LAND OF SCIENCE. 2 1

ing upward in a row of tentacles. The coral is se-
creted in the body of the polyp out of the carbonate
of lime in the sea. Thus the coral animalcule rears
its polypidom or rocky structure in warm latitudes,
and constructs reefs or barriers around islands. It
is limited in range of depth from 25 to 30 fathoms.
Chemically considered, coral is carbonate of lime;
physiologically, it is the skeleton of an animal; geo-
graphically, it is characteristic of warm latitudes, es-
pecially of the Pacific Ocean." This description is
correct, and even very fairly complete, if you know
enough of the subject to understand it. But tell me,
does it lead you to love my piece of coral ? Have you
any picture in your mind of the coral animal, its home,
or its manner of working ?

But now, instead of trying to master this dry, hard
passage, take Mr. Huxley's penny lecture on Coral
and Coral Reefs,* and with the piece of coral in your
hand, try really to learn its history. You will then be
able to picture to yourself the coral animal as a kind
of sea-anemone, something like those which you have
often seen, resembling red, blue, or green flowers, put-
ting out their feelers in sea-water on our coasts, and
drawing in the tiny sea-animals to digest them in that
bag of fluid which serves the sea-anemone as a stom-
ach. You will learn how this curious jelly animal can
split itself in two, and so form two polyps, or send a
bud out of its side and so grow up into a kind of " tree
or bush of polyps," or how it can hatch little eggs in-
side it and throw out young ones from its mouth,

* Manchester Science Lectures, No. i, Second Series. John
Hey wood, 141, Deansgate, Manchester.
3

22 THE FAIRY-LAND OF SCIENCE.

provided with little hairs, by means of which they
swim to new resting-places. You will learn the dif-
ference between the animal which builds up the red
coral as its skeleton, and the group of animals which
build up the white; and you will look with new in-
terest on our piece of white coral, as you read that
each of those little cups on its stem with delicate divi-
sions like the spokes of a wheel has been the home of
a separate polyp, and that from the sea-water each little
jelly animal has drunk in carbonate of lime as you
drink in sugar dissolved in water, and then has used
it grain by grain to build that delicate cup and add to
the coral tree.

We cannot stop to examine all about coral now, we
are only learning how to learn, but surely our speci-
men is already beginning to grow interesting; and
when you have followed it out into the great Pacific
Ocean, where the wild waves dash restlessly against
the coral trees, and have seen these tiny drops of jelly
conquering the sea and building huge walls of stone
against the rough breakers, you will hardly rest till
you know all their history. Look at that curious
circular island in the picture (Fig. 3), covered with
palm trees; it has a large smooth lake in the mid-
dle, and the bottom of this lake is covered with
blue, red, and green jelly animals, spreading out their
feelers in the water and looking like beautiful flow-
ers, and all round the outside of the island similar
animals are to be seen washed by the sea waves.
Such islands as this have been built entirely of the
skeletons of the coral animals, and the history of the
way in which the tiny creatures added to them inch

TliK FAIRY-LAND OF SCIENCE.

by inch, is as fascinating as the story of the binkiing
of any fairy palace in the days of old. Read all this,

Fig. 3.— Coral islam

and then i£ you have no coral of your own to examine,
g'o to some musernn and see the beautiful specimens
in the glass cases there, and think that they have been
built up under the rolling surf by the tiny jelly ani-
mals; and then coral will become a real living thing
to you, and you will love the thoughts it awakens.

But people often ask, what is the use of learning
all this? If you do not feel by this time how delight-
ful it is to fill your mind with beautiful pictures of
nature, perhaps it would be useless to say more. But
in this age of ours, when restlessness and love of ex-
citement pervade so manv lives, is it nothing to be

THE FAIRY-LAND OF SCIENCE.

taken out of ourselves and made to look at the won-
ders of nature going on around us? Do you never feel
tired and " out of sorts," and want to creep away from
your companions, because they are merry and you
are not? Then it is the time to read about the stars,
and how quietly they keep their course from age to
age; or to visit some. little flower, and ask what story
it has to tell ; or to watch the clouds, and try to im-
agine how the winds drive them across the sky. No
person is so independent as he who can find interest
in a bare rock, a drop of water, the foam of the sea,
the spider on the wall, the flower underfoot or the
stars overhead. And these interests are open to every-
one who enters the fairy-land of science.

Moreover, we learn from this study to see that there
is a law and purpose in everything in the Universe,
and it makes us patient when we recognize the quiet
noiseless working of nature all around us. Study
light, and learn how all colour, beauty, and life depend
on the sun*s rays ; note the winds and currents of the
air, regular even in their apparent irregularity, as they
carry heat and moisture all over the world. Watch
the water flowing in deep quiet streams, or forming
the vast ocean; and then reflect that every drop is
guided by invisible forces working according to fixed
laws. See plants springing up under the sunlight,
learn the secrets of plant life, and how their scents
and colours attract the insects. Read how insects
cannot live without plants, nor plants without the flit-
ting butterfly or the busy bee. Realize that all this
is worked by fixed laws, and that out of it (even if
sometimes in suffering and pain) springs the wonder-

THE FAIRY-LAND OF SCIENCE. 25

ful universe around us. And then say, can you fear
for your own little life, even though it may have its
troubles? Can you help feeling a part of this guided
and governed nature? or doubt that the power which
fixed the laws of the stars and of the tiniest drop of
water — ^that made the plant draw power from the sun,
the tiny coral animal its food from the dashing waves ;
that adapted the flower to the insect and the insect
to the flower — is also moulding your life as part of
the great machinery of the universe, so that you have
only to work, and to wait, and to love ?

We are all groping dimly for ^he Unseen Power,
but no one who loves nature and studies it can ever
feel alone or unloved in the world. Facts, as mere
facts, are dry and barren, but nature is full of life and
love, and her calm unswerving rule is tending to some
great though hidden purpose. You may call this Un-
seen Power what you will — may lean on it in loving,
trusting faith, or bend in reverent and silent awe ; but
even the little child who lives with nature and gazes
on her with open eye, must rise in some sense or other
through nature to nature's God.

26 THE FAIRY-LAA'D OF SCIENCE.

LECTURE II.

SUNBEAMS AND THE WORK THEY DO.

W',:;,.:;.'

■I love ihu sunbeams, and feel
1 incrrii:r as he watches them
, sparkling Uke diamonds on the

SUNBEAMS AND THEIR WORK, 27

ripples of the sea, or making bows of coloured light
on the waterfall? Is not the sunbeam so dear to us
that it has become a household word for all that is
merry and gay? and when we want to describe the
dearest, busiest little sprite among us, who wakes a
smile on all faces wherever she goes, do we not call
her the " sunbeam of the house " ?

And yet how little even the wisest among us know
about the nature and work of these bright messengers
of the sun as they dart across space !

Did you ever wake quite early in the morning,
when it was pitch-dark and you could see nothing,
not even your own hand; and then lie watching as
time went on till the light came gradually creeping in
at the window? If you have done this you will have
noticed that you can at first only just distinguish the
dim outline of the furniture ; then you can tell the dif-
ference between the white cloth on the table and the
dark wardrobe beside it; then by degrees all the small-
er details, the handles of the drawer, the pattern on
the wall, and the different colours of all the objects in
the room become clearer and clearer till at last you see
all distinctly in broad daylight.

What has been happening here ? and why have the
things in the room become visible by such slow de-
grees? We say that the sun is rising, but we know
very well that it is not the sun which moves, but that
our earth has been turning slowly round, and bringing
the little spot on which we live face to face with the
great fiery ball, so that his beams can fall upon us.

Take a small globe, and stick a piece of black
plaster over the United States, then let a lighted lamp

28 THE FAIRY-LAND OF SCIENCE.

represent the sun, and turn the globe slowly, so that
the spot creeps round from the dark side away from
the lamp, until it catches, first the rays which pass
along the side of the globe, then the more direct rays,
and at last stands fully in the blaze of the light. Just
this was happening to our spot of the world as you lay
in bed and saw the light appear ; and we have to learn
to-day what those beams are which fall upon us and
what they do for us.

First we must leam something about the sun itself,
since it is the starting- place of all the sunbeams. If
the sun were a dark mass instead of a fiery one we
should have none of these bright cheering messengers,
and though we were turned face to face with him every
day we should remain in one cold eternal night. Now
you wijl remember we mentioned in the last lecture
that it is heat which shakes apart the little atoms of
water and makes them float up in the air to fall again
as rain ; and that if the day is cold they fall as snow,
and all the water is turned into ice. But if the sun
were altogether dark, think how bitterly cold it would
be; far colder than the most wintry weather ever
known, because in the bitterest night some warmth
comes out of the earth, where it has been stored from
the sunlight which fell during the day. But if we
never received any warmth at all, no water would
ever rise up into the sky, no rain ever fall, no rivers
flow, and consequently no plants could grow and no
animals live. All water would be in the form of snow
and ice, and the earth would be one great frozen mass
with nothing moving upon it.

So you see it becomes very interesting for us to

SUNBEAMS AND THEIR WORK, 29

learn what the sun is, and how he sends us his beams.
How far away from us do you think he is ? On a fine
summer's day when we can see him clearly, it looks as
if we had only to get into a balloon and reach him as
he sits in the sky, and yet we know that he is more
than ninety-two millions of miles distant from our
earth.

These figures are so enormous that you cannot
really grasp them. But imagine yourself in an express
train, travelling at the tremendous rate of sixty miles
an hour and never stopping. At that rate, if you
wished to arrive at the sun to-day you would have
been obliged to start more than one hundred and
seventy-five years ago. That is, you must have set
off in the early part of the reign of Queen Anne, long
before the revolution by which America ceased to be
an English colony and became a free nation; all
through the days of Washington and the long line of
presidents; through the war of 1812; that with Mex-
ico, and the late war with Spain, up to the present
day whirling on day and night at express speed, and
at last, to-day, you would have reached the sun!

And when you arrived there, how large do you
think you would find him to be? Anaxagoras, a
learned Greek, was laughed at by his fellow Greeks
because he said that the sun was as large as the Pelo-
ponnesus — ^that is, about the size of a county of the
state in which you live. How astonished they would
have been if they could have known that not only is
he bigger than the whole of Greece, but more than a
million times bigger than the whole world !

Our world itself is a large place, so large that your

THE FAtRY-LAND OF SCIENCE.

own state looks only like a tiny speck upon it, and an
express train would take nearly a month to travel
round it. Yet even our whole globe is nothing in size
compared to the sun, for it only measures 8000 miles
across, while the sun measures more than 852,000.

Fl:;. 4.— log earths laid across the face of the sun. Each one of
thc^e dots represents roughly the size of the earth as com-
pared to the size of the sun represented by the large circle.

Imagine for a moment that you could cut the sun
and the earth each in half as you would cut an apple;
then if you were to lay the flat side of the half-earth on

SUNBEAMS AND THEIR WORK, 31

the flat side of the half-sun it would take 109 such
earths to stretch across the face of the sun. One of
these 109 round spots on the diagram represents the
size which our earth would look if placed on the sun ;
and they are so tiny compared to him that they look
only like a string of minute beads stretched across his
face. Only think, then, how many of these minute
dots would be required to fill the whole of the inside of
Fig. 4, if it were a globe !

One of the best ways to form an idea of the whole
size of the sun is to imagine it to be hollow, like a
hollow air ball, and then see how many earths it
would take to fiirit. You would hardly beheve that
it would take one million three hundred and thirty-one
thousand globes the size of our world squeezed to-
gether. Just think, if a huge giant could travel all
over the universe and gather worlds, all as big as ours,
and were to make first a heap of merely ten such
worlds, how huge it would be ! Then he must have a
hundred such heaps of ten to make a thousand worlds ;
and then he must collect again a thousand times that
thousand to make a million, and when he had stuffed
them all into the sun-ball he would still have only
filled three-quarters of it !

After hearing this you will not be astonished that
such a monster should give out an enormous quantity
of light and heat; so enormous that it is almost im-
possible to form any idea of it. Sir John Herschel
has, indeed, tried to picture it for us. He found that
a ball of lime with a flame of oxygen and hydrogen
playing round it (such as we use in magic lanterns
and call oxy-hydrogen light) becomes so violently

THE FAIRY-LAND OF SCIENCE,

hot that it gives, with the exception of that produced
by electricity, the most brilliant artificial light we can
get — such that you cannot put your eye near it with-
out injury. Yet if you wanted to have a light as
strong as that of our sun, it would not be enough to
make such a lime-ball as big as the sun is. No, you
must make it as big as 146 suns, or more than
146,000,000 times as big as our earth, in order to get
the right amount of light. Then you would have a
tolerably good artificial sun; for we know that the
body of the sun gives out an intense white light, just
as the lime-ball does, and that, like it, it has an atmos-
phere of glowing gases round it.

But perhaps we get the best idea of the mighty
heat and light of the sun by remembering how few of
the rays which dart out on all sides from this fiery
ball can reach our tiny globe, and yet how powerful
they are. Look at the globe of a lamp in the middle of
the room, and see how its light pours out on all sides
and into every corner; then take a grain of mustard-
seed, which will very well represent the comparative
size of our earth, and hold it up at a distance from the
lamp. How very few of all those rays which are
filling the room fall on the little mustard-seed, and
just so few does our earth catch of the rays which
dart out from the sun. And yet this small quantity
(^yjij^millionth part of the whole) does nearly all the
work of our world.*

* These and the preceding numerical statements will be found
worked out in Sir J. Herschel's Familiar Lectures on Scien-
tific Subjects, 1868, from which many of the facts in the first
part of the lecture are taken.

SUNBEAMS AND THEIR WORK. 33

In order to see how powerful the sun's rays are,
you have only to take a magnifying glass and gather
them to a point on a piece of brown paper, for they
will set the paper alight. Sir John Herschel tells us
that at the Cape of Good Hope the heat was even
so great that he cooked a beefsteak and roasted some
eggs by merely putting them in the sun, in a box
with a glass lid! Indeed, just as we should all be
frozen to death if the sun were cold, so we should
all be burnt up with intolerable heat if his fierce rays
fell with all their might upon us. But we have an
invisible veil protecting us, made — of what do you
think? Of those tiny particles of water which the
sunbeams draw up and scatter in the air, and which,
as we shall see in Lecture IV, cut off part of the in-
tense heat and make the air cool and pleasant for us.

We have now learnt something of the distance, the
size, the light, and the heat of the sun — the great
source of the sunbeams. But we are as yet no nearer
the answer to the question. What is a sunbeam? how
does the sun touch our earth?

Now suppose I wish to touch you from this plat-
form where I stand, I can do it in two ways. Firstly,
I can throw something at you and hit you — in this
case a thing will have passed across the space from
me to you. Or, secondly, if I could make a violent
movement so as to shake the floor of the room, you
would feel a quivering motion ; and so I should touch
you across the whole distance of the room. But in
this case no thing would have passed from me to you
but a movement or %i}ave, which passed along the

THE FAIRY-LAND OF SCIENCE,

boards of the floor. Again, if I speak to you, how
does the sound reach your ear? Not by anything
being thrown from my mouth to your ear, but by
the motion of the air. When I speak I agitate the
air near my mouth, and that makes a wave in the air
beyond, and that one, another, and another (as we
shall see more fully in Lecture VI), till the last wave
hits the drum of your ear.

Thus we see there are two ways of touching any-
thing at a distance: ist, by throwing some thing at it
and hitting it; 2nd, by sending a movement or i<.'avc
across to it, as in the case of the quivering boards and
the air.

Now the great natural philosopher Newton thought
that the sun touched us in the first of these ways, and
that sunbeams were made of very minute atoms of
matter thrown out by the sun, and making a perpetual
cannonade on our eyes. It is easy to understand
that this would make us see light and feel heat, just as
a blow in the eve makes us see stars, or on the bodv
makes us feel hot : and for a long time this explanation
was supposed to be the true one. But we know now
that there are many facts which cannot be explained
on this theory, though we cannot go into them here.
What we will do, is to try and understand what
now seems to be the true explanation of a sun-
beam.

About the same time that Newton wrote, a Dutch-
man, named Huyghens, suggested that light comes
from the sun in tiny waves, travelling across space
much in the same way as ripples travel across a pond.
The only difficulty was to explain in what substance

SUNBEAMS AND THEIR WORK, 35

these waves could be travelling: not through water,
for we know that there is no water in space — nor
through air, for the air ceases at a comparatively short
distance from our earth. There must then be some-
thing filling all space between us and the sun, finer
than either water or air.

And now I must ask you to use all your imagina-
tion, for I want you to picture to yourselves something
quite as invisible as the Emperor's new clothes in
Andersen's fairy-tale, only with this difference, that
our invisible something is very active ; and though we
can neither see it nor touch it we know it by its
effects. You must imagine a fine substance filling all
space between us and the sun and the stars; a sub-
stance so very delicate and subtle, that not only is
it invisible, but it can pass through solid bodies such
as glass, ice, or even wood or brick walls. This sub-
stance we call " ether." I cannot give you here the
reasons why we must assume that it is throughout
all space ; you must take this on the word of such men
as Sir John Herschel or Professor Clerk-Maxwell,
until you can study the question for yourselves.

Now if you can imagine this ether filling every
corner of space, so that it is everywhere and passes
through everything, ask yourselves, what must happen
when a great commotion is going on in one of the
large bodies which float in it? When the atoms of
the gases round the sun are clashing violently together
to make all its light and heat, do you not think they
must shake this ether all around them? And then,
since the ether stretches on all sides from the sun to
our earth and all other planets, must not this quiver-

36 THE FAIRY-LAND OF SCIENCE.

ing travel to us, just as the quivering of the boards
would from me to you ? Take a basin of water to rep-
resent the ether, and take a piece of potassium like
that which we used in our last lecture, and hold it
with a pair of nippers in the middle of the water. You
will see that as the potassium hisses and the flame
burns round it, they will make waves which will
travel all over the water to the edge of the basin, and
you can imagine how in the same way waves travel
over the ether from the sun to us.

Straight away from the sun on all sides, never
stopping, never resting, but chasing after each other
with marvellous quickness, these tiny waves travel
out into space by night and by day. When the spot
of the earth where America lies is turned away from
them and they cannot touch you, then it is night for
you, but directly America is turned so as to face the
sun, then they strike on the land, and the water, and
warm it ; or upon your eyes, making the nerves quiver
so that you see light. Look up at the sun and picture
to yourself that instead of one great blow from a fist
causing you to see stars for a moment, millions of tiny
blows from these sun-waves are striking every instant
on your eye ; then you will easily understand that this
would cause you to see a constant blaze of light.

But when the sun is away, if the night is clear we
have light from the stars. Do these then too make
waves all across the enormous distance between them
and us ? Certainly they do, for they too are suns like
our own, only they are so far off that the waves they
send are more feeble, and so we only notice them
when the sun's stronger waves are away.

SUNBEAMS AND THEIR WORK,

But perhaps you will ask, if no one has ever seen
these waves or the ether in which they are made,
what right have we to say they are there ? Strange as
it may seem, though we cannot see them we have
measured them and know how large they are, and how
many can go into an inch of space. For as these tiny
waves are running on straight forward through the
room, if we put something in their way, they will have
to run round it ; and if you let in a very narrow ray of
light through a shutter and put an upright wire in the
sunbeam, you actually make the waves run round the
wire just as water runs round a post in a river; and

Fig. 5. — A, hole in the shutter ; B, wire placed in the beam of
light ; S S, screen on which the dark and light bands are
caught.

they meet behind the wire just as the water meets in a
V shape behind the post. Now when they meet, they
run up against each other, and here it is we catch
them. For if they meet cfJmfortably, both rising up
in a good wave, they run on together and make a
bright line of light; but if they meet higgledy-pig-
4

38 THE FAIRY-LAND OF SCIENCE.

gledy, one up and the other down, all in confusion,
they stop each other, and then there is no light, but
a line of darkness. And so behind your piece of
wire you can catch the waves on a piece of paper,
and you will find they make dark and light lines one
side by side with the other, and by means of these
bands it is possible to find out how large the waves
must be. This question is too difficult for us to work
it out here, but you can see that large waves will make
broader light and dark bands than small ones will,
and that in this way the size of the waves may be
measured.

And now how large do you think they turn out
to be? So very, very tiny that about fifty thousand
waves are contained in a single inch of space! I
have drawn on the board the length of an inch,* and
now I will measure the same space in the air between
my finger and thumb. Within this space at this mo-
ment there are fifty thousand tiny waves moving up
and down ! I promised you we would find in science
things as wonderful as in fairy tales. Are not these
tiny invisible messengers coming incessantly from the
sun as wonderful as any fairies? and still more so
when, as we shall see presently, they are doing nearly
all the work of our world.

We must next try to realize how fast these waves
travel. You will remember that an express train
would take more than one hundred and seventy-
five years to reach us from the sun; and even a
cannon-ball would take from ten to thirteen years
to come that distance. Well, these tiny waves

* The width of an inch may be seen in Fig. 13, p. 64.

SUNBEAMS AND THEIR WORK,

take only seven minutes and a half to come the whole
92 millions of miles. The waves which are hitting
your eye at this moment are caused by a movemeni
which began at the sun only 7^ minutes ago. And re-
member, this movement is going on incessantly, and
these waves are always following one after the other so
rapidly that they keep up a perpetual cannonade
upon the pupil of your eye. So fast do they come
that about 608 billion waves enter your eye in one
single second.* I do not ask you to remember these
figures; I only ask you to try and picture to your-
selves these infinitely tiny and active invisible mes-
sengers from the sun, and to acknowledge that light is
a fairy thing.

But we do not yet know all about our sunbeam.
See, I have here a piece of glass with three sides, called
a prism. If I put it in the

sunlight which is streaming /\ /

through the window, what ^

happens? Look! on the ^^^- ^•

table there is a line of beautiful colours. I can make
it long or short, as I turn the prism, but the colours
always remain arranged in the same way. Here at
my left hand is the red, beyond it orange, then yellow,
green, blue, indigo or deep blue, and violet, shading
one into the other all along the line. We have all
seen these colours dancing on the wall when the sun

* Light travels at the rate of 192,000 miles, or 12,165,120,000
inches, in a second. Taking the average number of wave-
lengths in an inch at 50,000, then 12,165,120,000 X 50.000 = 608,-
256,000,000,000.

THE FAIRY-LAND OF SCIENCE,

has been shining brightly on the cut-glass pendants
of the chandelier, and you may see them still more
distinctly if you let a ray of light into a darkened

room, and pass
it through the
prism as in the
diagram (Fig. 7).
What are these
colours? Do they
come from the
glass? No; for
you will remem-
ber to have seen
them in the rain-
bow, and in the

Fig. 7. — Coloured spectrum thrown by a
prism on the wall. D E, window-shut-
ter ; F, round hole in it ; ABC, glass-
prism ; M N, wall.

soap-bubble, and even in a drop of dew or the scum
on the top of a pond. This beautiful coloured line is
only our sunbeam again, which has been split up into
many colours by passing through the glass, as it is in
the rain-drops of the rainbow and the bubbles of the
scum of the pond.

Till now we have talked of the sunbeam as if it were
made of only one set of waves, but in truth it is made
of many sets of waves of different sizes, all travelling
along together from the sun. These various waves
have been measured, and we know that the waves
which make up red light are larger and more lazy than
those which make violet light, so that there are only
thirty-nine thousand red weaves in an inch, while there
are fifty-seven thousand violet waves in the same space.

How is it then, that if all these diflferent waves,
making diflferent colours, hit on our eye, they do not

Sl/.VBEAAfS A\D THEIR WORK.

always make us see coloured light? Because, unless
they are interfered with, they all travel along together,
and you know that all colours mixed together in
proper proportion, make white.

I have here a round piece of cardboard, painted
with the seven colours in succession several times over.
When it is still you can distinguish them all apart, but
when I whirl it quickly round — see! — the cardboard
looks quite white, because we see them all so instan-
taneously that they are mingled together. In the same
way light looks white to you, because all the differ-
ent coloured waves strike on your eye at once. You
can easily make one of these cards for yourselves,
only the white will always look dirty, because you
cannot get the col-
ours pure.

Now, when t
light passes through
the three- sided gl;
or prism, the waves '
are spread out, and
the slow, heav}', red
waves lag behind and
remain at the lower
end R of the coloured
line on the wall (Fig. i^e se(

7), while the rapid ^' ^^"'

little violet waves are
bent more out of their road and r
end of the line; and the orange, yellow, green, blue,
and indigo arrange themselves between, according to
the size of their waves.

, cardboard painlei
le cardboard spun

ckly

1 to V at the farther

THE FAIRY-LAND OF SCIENCE,

those which pass into the wall, by giving motion to its
atoms, lose their own vibrations.

Into polished shining metal the waves hardly enter
at all, but are thrown back from the surface ; and so a
steel knife or a silver spoon are very bright, and are
clearly seen. Quicksilver is put at the back of look-
ing-glasses because it reflects so many waves. It not
only sends back those which come from the sun, but
those, too, which come from your face. So, when you
see yourself in a looking-glass, the sun-waves have first
played on your face and bounded off from it to the
looking-glass; then, when they strike the looking-
glass, they are thrown back again on to the retina of
your eye, and you see your own face by means of the
very waves you threw off from it an instant before.

But the reflected light-waves do more for us than
this. They not only make us see things, but they
make us see them in different colours. What, you
will ask, is this too the work of the sunbeams? Cer-
tainly ; for if the colour we see depends on the size of
the waves which come back to us, then we must see
things coloured differently according to the waves they
send back. For instance, imagine a sunbeam playing
on a leaf : part of its waves bound straight back from
it to our eye and make us see the surface of the leaf,
but the rest go right into the leaf itself, and there
some of them are used up and kept prisoners. The
red, orange, yellow, blue, and violet waves are all
useful to the leaf, and it does not let them go again.
But it cannot absorb the green waves, and so it throws
them back, and they travel to your eye and make you
see a green colour. So when you say a leaf is green,

SUNBEAMS AND THEIR WORK. 45

you mean that the leaf does not want the green waves
of the sunbeam, but sends them back to you. In the
same way the scarlet geranium rejects the red waves ;
this table sends back brown waves ; a white tablecloth
sends back nearly the whole of the waves, and a black
coat scarcely any. This is why, when there is very
little light in the room, you can see a white tablecloth
while you would not be able to distinguish a black
object, because the few faint rays that are there, are
all sent back to you from a white surface.

Is it not curious to think that there is really no
such thing as colour in the leaf, the table, the coat,
or the geranium flower, but we see them of different
colours because, for some reason, they send back only
certain coloured waves to our eye?

Wherever you look, then, and whatever you see, all
the beautiful tints, colours, lights, and shades around
you are the work of the tiny sun-waves.

Again, light does a great deal of work when it falls
upon plants. Those rays of light which are caught
by the leaf are by no means idle ; we shall see in Lec-
ture VII that the leaf uses them to digest its food and
make the sap on which the plant feeds.

We all know that a plant becomes pale and sickly
if it has not sunlight, and the reason is, that without
these light-waves it cannot get food out of the air, nor
make the sap and juices which it needs. When you
look at plants and trees growing in the beautiful
meadows ; at the fields of corn, and at the lovely land-
scape, you are looking on the work of the tiny waves
of light, which never rest all through the day in help-
ing to give life to every green thing that grows.

46 THE FAIRY-LAND OF SCIENCE.

So far we have spoken only of light ; but hold your
hand in the sun and feel the heat of the sunbeams, and
then consider if the waves of heat do not do work
also. There are many waves in a sunbeam which
move too slowly to make us see light when they hit
our eye, but we can feel them as heat, though we
cannot see them as light. The simplest way of feeling
heat-waves is to hold a warm iron near your face.
"You know that no light comes from it, yet you can feel
the heat-waves beating violently against your face and
scorching it. Now there are many of these dark heat-
rays in a sunbeam, and it is they which do most of
the work in the world.

In the first place, as they come quivering to the
earth, it is they which shake the water-drops apart, so
that these are carried up in the air, as we shall see in
the next lecture. And then remember, it is these
drops, falling again as rain, which make the rivers and
all the moving water on the earth. So also it is the
heat-waves which make the air hot and light, and so
cause it to rise and make winds and air-currents, and
these again give rise to ocean-currents. It is these
dark rays, again, which strike upon the land and give
it the warmth which enables plants to grow. It is
they also which keep up the warmth in our own bodies,
both by coming to us directly from the sun, and also
in a very roundabout way through plants. You will
remember that plants use up rays of light and heat
in growing ; then either we eat the plants, or animals
eat the plants and we eat the animals ; and when we
digest the food, that heat comes back in our bodies,
which the plants first took from the sunbeam.

SUNBEAMS AND THEIR WORK. 47

Breathe upon your hand, and feel how hot your breath
is ; well, that heat which you feel, was once in a sun-
beam, and has travelled from it through the food you
have eaten, and has now been at work keeping up the
heat of your body.

But there is still another way in which these plants
may give out the heat-waves they have imprisoned.
You will remember how we learnt in the first lecture
that coal is made of plants, and that the heat they
give out is the heat these plants once took in. Think
how much work is done by burning coal. Not only
are our houses warmed by coal fires and lighted by
coal gas, but our steam-engines and machinery work
entirely by water which has been turned into steam by
the heat of coal and coke fires; and our steamboats
travel all over the world by means of the same power.
In the same way the oil of our lamps comes from coal
and the remains of plants and animals in the earth.
Even our tallow candles are made of mutton fat, and
sheep eat grass; and so, turn which way we will, we
find that the light and heat on our earth, whether it
comes from fires, or candles, or lamps, or gas, and
whether it moves machinery, or drives a train, or pro-
pels a ship, is equally the work of the invisible waves of
ether coming from the sun, which make what we call
a sunbeam.

Lastly, there are still some hidden waves which we
have not yet mentioned, which are not useful to us
either as light or heat, and yet they are not idle.

Before I began this lecture, I put a piece of paper,
which had been dipped in nitrate of silver, under a
piece of glass; and between it and the glass I put a

^8 THE FAIHY-LA\D OF SCIENCE.

piece of lace. Look what the sun has been doing
while I have been speaking. It has been breaking up
the nitrate of silver on the paper and turning it into
a deep brown substance ; only where the threads of
the lace were, and the sun could not touch the nitrate
of silver, there the paper has remained light-col on red,
and by this means I have a beautiful impression of the
lace on the paper. I will now dip the impression into
water in which some hyposulphite of soda is dissolved,
and this will " fix " the picture, that is, prevent the
sun acting upon it any more; then the picture will
remain distinct, and 1 can pass it round to you all.
Here, again, invisible waves have been at work, and

Yk. 9.

photographed during the lecture.

this time neither as light nor as heat, but as chemical
agents, and it is these waves which give us all our
beautiful photographs. In any toyshop you can buy
this prepared paper, and set the chemical waves at
work to make pictures. Only you must remember
to fix it in the solution afterward, otherwise the chemi-

1 k.

SUNBEAMS AND THEIR WORK.

cal rays will go on working after you have taken the
lace away, and all the paper will become brown and
your picture will disappear.

The action of the photographic rays was well
known long before I delivered these lectures, twenty
years ago.

But since some still more marvellous and wonder-
working rays have been discovered. These rays were
studied and their curious action first shown by Profes-
sor Rontgen, of Wiirzburg ; therefore they are some-
times called the Rontgen rays, and sometimes the
X-rays, because X stands in algebra for an unknown
quantity; and although we know how these rays act,
we do not yet know what they are, except that they
are not ordinary forms of heat, light, or electricity.

They are produced by inserting platinum wires,
one at each end, into a glass tube from which the air
has been withdrawn so as to make almost a perfect
vacuum. These wires are then connected with an
electric battery, and a current of electricity at very
high pressure is passed through the tube, producing
a bluish-green light. But just before the current
passes out at the other end of the tube, there is a dark
space seen in which there is no bluish-green light.
It is in this space that the X-rays lie. They are quite
invisible in themselves, but if a screen is placed in
their road, painted over with a fluorescent substance
(such as the luminous paint put on matchbox cases),
they set up vibrations in the paint which cause it to
glow brilliantly.

Now comes the wonderful part. If you make this
screen of cardboard or wood, and turn the painted side

5°

TRE FAIRY-LAND OF SCIENCE.

QH'oj.from the vacuum tube, it will still glow brightly.
And if you then put your hand between the tube and
the screen you will see the bones of your hand on the
glowing paint, exactly as shown in Fig. lo. The X-rays
will have passed almost entirely through the fiesh of
your hand and through the wood or cardboard, throw-
ing only a very faint shadow upon the screen, while
the bones will have stopped
them altogether, and so cast a
deep black shadow. You will
see that the ring on the finger
also casts a deep shadow,
showing that the X-rays could
not pass through the gold.

I have done this myself
and seen the bones of my own
hand, and I have made an
equally strange experiment.
I held a stout leather bag be-
tween the tube and the screen,
and lo! the leather of the bag
became only a very faint shad-

aame rays. ^^^ j.j^^ ^^^ ?it&\i of my hand

had done, and I saw upon the screen the metal frame-
work of the bag, and within it a bunch of keys, an
opera glass, and several coins which were shut up in-
side the bag.

The reason of all these marvels is that the X-rays
will pass through flesh, wood, leather, paper, card-
board, even through a pack of cards, and through sev-
eral other substances which entirely stop the ordinary
rays of light and heat. But they will not pass through

t.;. T

o.— Shadow of

ihe

hiin

lanhandasthn

own

the fluores

cent

scrc

en by the X-r

ays.

Alsi

J as shown w

hen

photographed by

the

SUNBEAMS AND THEIR WORK. 51

bone nor through heavy metals. Therefore the frame-
work of the bag, the brass tubes of the opera glass,
the coins, and the bunch of keys stopped them alto-
gether and threw deep shadows. It is not necessary
to make these rays visible in order to enable them to
do work. If you take the fluorescent screen away and
put in its place a properly prepared photographic
plate, wrapped in black paper to keep out the light-
rays, or in a wooden box, and place your hand again
in front of the tube, the X-fays will pass through your
flesh and through the black paper, or the wood, and
cast the shadow of your bones and ring upon the plate,
altering the chemicals everywhere except where this
shadow lies. Then when the plate is taken out, prop-
erly developed, and printed on paper you will have the
image shown in Fig. 10 just as we had the impres-
sion of the lace just now.

Is not this like a magician's story ! And it has the
advantage of being useful to mankind, for surgeons
now use these X-rays to see the exact spot where bul-
lets or other solid objects are buried in the flesh of
people's bodies, so that they can cut them out. These
rays have several other curious properties, and we do
not yet know half the wonders they may reveal to us,
but they teach us how much more we have still to learn
about sunbeams and their work.

And now, tell me, may we not honestly say, that
the invisible waves which make our sunbeams, are
wonderful fairy messengers as they travel eternally
and unceasingly across space, never resting, never
tiring in doing the work of our world? Little as we
have been able to learn about them in one short hour,

THE AERIAL OCEAX iX WBJCB WE UVE. 53

LECTURE IIL

tIAL OCEA.V IX WHICH W"E LIVE.

sit OTi the bank of a river in some quiet spot where
the water was deep and clear, and watch the fishes
swimminpf lazily along? When I was a child this was
one of my favourite occupations in the summertime

54 . THE FAIRY-LAND OF SCIENCE.

on the banks of the Thames, and there was one ques-
tion which often puzzled me greatly, as I watched the
minnows and gudgeon gliding along through the
water. Why should fishes live in something and be
often buffeted about by waves and currents, while I
and others lived on the top of the earth and not in
anything? I do not remember ever asking any one
about this ; and if I had, in those days people did not
pay much attention to children's questions, and prob-
ably nobody would have told me, what I now tell
you, that we do live in something quite as real and
often quite as rough and stormy as the water in which
the fishes swim. The something in which we live is
air, and the reason that we do not perceive it is,
that we are in it, and that it is a gas, and invisible to
us ; while we are above the water in which the fishes
live, and it is a liquid which our eyes can perceive.

But let us suppose for a moment that a being,
whose eyes were so made that he could see gases as we
see liquids, were looking down from a distance upon
our earth. He would see an ocean of air, or aerial
ocean, all round the globe, with birds floating about in
it, and people walking along the bottom, just as we see
fish gliding along the bottom of a river. It is true, he
would never see even the birds come near to the sur-
face, for the highest-flying bird, the condor, never
soars more than five miles from the ground, and our
atmosphere, as we shall see, is at least lOO miles high.
So he would call us all deep-air creatures, just as we
talk of the deep-sea animals; and if we can imagine
that he fished in this air-ocean, and could pull one of
us out of it into space, he would find that we should

THE AERIAL OCEAN IN WHICH WE UVE, 55

gasp and die just as fishes do when pulled out of the
water.

He would also observe very curious things going
on in our air-ocean ; he would see large streams and
currents of air, which we call vjinds, and which would
appear to him as ocean-currents do to us, while near
down to the earth he would see thick mists forming
and then disappearing again, and these would be our
clouds. From them he would see rain, hail and snow
falling to the earth, and from time to time bright
flashes would shoot across the air-ocean, which would
be our lightning. Nay even the brilliant rainbow,
the northern aurora borealis, and the falling stars,
which seem to us so high up in space, would be seen
by him near to our earth, and all within the aerial
ocean.

But as \/e know of no such being living in space,
who can tell us what takes place in our invisible air,
and as we cannot see it ourselves, we must try by ex-
periments to see it with our imagination, though we
cannot with our eyes.

First, then, can we discover what air is? At one
time it was thought that it was a simple gas and could
not be separated into more than one kind. But we are
now going to make an experiment by which it has
been shown that air is made of two gases mingled
together, and that one of these gases, called oxygen, is
used up when anything burns, while the other nitrogen
is not used, and only serves to dilute the minute atoms
of oxygen. I have here a glass bell-jar, with a cork,
fixed tightly in the neck, and I place the jar over a
pan of water, while on the water floats a plate with

ir (Ros

56 THE FAIRY-LAND OF SCIENCF,.

a small piece of phosphorus upon it. You will see that
by putting the bell-jar over the water, I have shut
ill a certain quantity of air, and my object now is to
use up the oxygen
out of this air and
leave onJy nitro-
gen behind. To
do this I must
light the piece of
phosphorus, for
you will remem-
ber it is in burn-
ing that oxygen
is used up: I will
take the cork out, light the phosphorus, and cork up
the jar again. See! as the phosphorus burns white
fumes fill the jar. These fumes are phosphoric acid,
which is a substance made of phosphorus and oxygen.
Our fairy force " chemical attraction " has been at
work here, joining the phosphorus and the oxygen of
the air together.

Now, phosphoric acid melts in water just as sugar
does, and in a few minutes these fumes will disappear.
They are beginning to melt already, and the water
from the pan is rising up in the bell-jar. Why is this?
Consider for a moment what we have done. First, the
jar was full of air, that is, of mixed oxygen and nitro-
gen ; then the phosphorus used up the oxygen, making
white fumes; afterward, the water sucked np these
fumes; and so, in the jar now nitrogen is the only
gas left, and the water has risen up to fill all the rest
of the space that was once taken up with the oxygen.

THE AERIAL OCEAN IN WHICH WE LIVE. 57

We can easily prove that there is no oxygen now
in the jar. I take out the cork and let a lighted taper
down into the gas. If there were any oxygen the
taper would burn, but you see it goes out directly,
proving that all the oxygen has been used up by the
phosphorus. When this experiment is made very
accurately, we find that for every pint of oxygen in air
there are four pints of nitrogen, so that the active
oxygen-atoms are scattered about, floating in the
sleepy, inactive nitrogen.

It is these oxygen-atoms which we use up when we
breathe. If I had put a mouse under the bell-jar,
instead of the phosphorus, the water would have risen
just the same, because the mouse would have breathed
in the oxygen and used it up in its body, joining it to
carbon and making a bad gas, carbonic acid, which
would also melt in the water, and when all the oxygen
was used the mouse would have died.

Do you see now how foolish it is to live in rooms
that are closely shut up, or to hide your head under
the bedclothes when you sleep? You use up all the
oxygen-atoms, and then there are none left for you to
breathe ; and besides this, you send out of your mouth
bad fumes, though you can not see them, and these
when you breathe them in again, poison you and make
you ill.

Perhaps you will say. If oxygen is so useful, why is
not the air made entirely of it? But think for a
moment. If there was such an immense quantity of
oxygen, how fearfully fast everything would burn !
Our bodies would soon rise above fever heat from the
quantity of oxygen we should take in, and all fires and

58 THE FAIRY-LAND OF SCIENCE.

lights would burn furiously. In fact, a flame once
lighted would spread so rapidly that no power on earth
could stop it, and everything would be destroyed. So
the lazy nitrogen is very useful in keeping the oxygen-
atoms apart; and we have time, even when a fire is
very large and powerful, to put it out before it has
drawn in more and more oxygen from the surround-
ing air. Often, if you can shut a fire into a closed
space, as in a closely-shut room or the hold of a ship,
it will go out, because it has used up all the oxygen in
the air.

So, you see, we shall be right in picturing this in-
visible air all around us as a mixture of two gases.
But when we examine ordinary air very carefully, we
find small quantities of other gases in it, besides oxy-
gen and nitrogen. First, there is carbonic-acid gas.
This is the bad gas which we give out of our mouths
after we have burnt up the oxygen with the carbon
of our bodies inside our lungs ; and this carbonic acid
is also given out from everything that burns. If only
animals lived in the world, this gas would soon poison
the air ; but plants get hold of it, and in the sunshine
they break it up again, as we shall see in Lecture VII,
and use up the carbon, throwing the oxygen back
into the air for us to use. Secondly, there are very
small quantities in the air of ammonia, or the gas which
almost chokes you in smelling-salts, and which, when
liquid, is commonly called " spirits of hartshorn.'*
This ammonia is useful to plants, as we shall see by
and by. Again, there is a great deal of water in the
air, floating about as invisible vapour or water-dust,
and this we shall speak of in the next lecture. Lastly,

THE AERIAL OCEAN IN WHICH WE LIVE.

the air we breathe is now found by no means the simple
mixture of oxygen and nitrogen, with a Httle car-
bonic acid and still less ammonia, which were all that
science had discovered in it till within the last few
years. We must add to the invisible mixture, not
only argon, whose presence in the atmosphere was
detected about three years ago, and crypton, a more
recent discovery, but two more constituents which
are believed to be simple or elementary substances,
neon and metargon. Still, all these gases and va-
pours in the atmosphere are in very small quantities,
and the bulk of the air is composed of oxygen and
nitrogen.

Having now learned what air is, the next question
which presents itself is. Why does it stay round our
earth ? You will remember we saw in the first lecture,
that all the little atoms of gas are trying to fly away
from each other, so that if I turn on this gas-jet the
atoms soon leave it, and reach you at the farther end
of the room, and you can smell the gas. Why, then,
do not all the atoms of oxygen and nitrogen fly away
from our earth into space, and leave us without any
air?

Ah ! here you must look for another of our invisible
forces. Have you forgotten our giant force, " gravita-
tion," which draws things together from a distance?
This force draws together the earth and the atoms of
oxygen and nitrogen ; and as the earth is very big and
heavy, and the atoms of air are light and easily moved,
they are drawn down to the earth and held there by
gravitation. But for all that, the atmosphere does not

THE FAIRY-LA.XD OF SCIENCE.

leave off trj'ing to fly away; it is always pressing up-
ward and outward with all its might, while the earth
is doing its best to hold it down.

The effect of this is, that near the earth, where the
pull downward is very strong, the air-atoms are drawn
very closely together, because gravitation gets the best
in the struggle. But as we get farther and farther
from the earth, the pull downward becomes weaker,
and then the air-atoms spring farther apart, and the
air becomes thinner. Suppose that the lines in this

oS_pb ,

diagram represent layers of air. Near the earth we
have to represent them as lying closely together, but
as they recede from the earth they are also farther
apart.

But the chief reason why the air is thicker or
denser nearer the earth, is because the upper layers
press it down. If you have a heap of papers lying
one on the top of the other, you know that those at
the bottom of the heap will be more closely pressed
together than those above, and just the same is the

THE AERIAL OCEAN IN WHICH WE LIVE. 6 1

case with the atoms of the air. Only there is this
difference, if the papers have lain for some time,
when you take the top ones off, the under ones remain
close together. But it is not so with the air, because
air is elastic, and the atoms are always trying to fly
apart, so that directly you take away the pressure they
spring up again as far as they can.

In this the ocean of air differs from an ocean of
water, for water is neither elastic nor can it be com-
pressed — except to a very small extent. If it were
otherwise the sea at great depths would be almost or
quite solid under the pressure of the enormous weight
of water above ; and even at a few fathoms below the
surface would present great resistance to bodies pass-
ing through it. Fish or marine animals could only
exist at or near the surface. At any considerable
depth the compressed water would hold sunken objects
embedded in it as does ice; nothing could reach the
bottom below a certain depth.

I have here an ordinary pop-gun. If I push the
cork in very tight, and then force the piston slowly
inward, I can compress the air a good deal. Now I
am forcing the atoms nearer and nearer together, but
at last they rebel so strongly against being more crowd-
ed that the cork can not resist their pressure. Out it
flies, and the atoms spread themselves out comfortably
again in the air all around them. Now, just as I
pressed the air together in the pop-gun, so the at-
mosphere high up above the earth presses on
the air below and keeps the atoms closely packed
together. And in this case the atoms cannot force
back the air above them as they did the cork in the

62 THE FAIRY-LAND OF SCIENCE.

pop-gun; they are obliged to submit to be pressed
together.

Even a short distance from the earth, however, at
the top of a high mountain, the air becomes lighter,
because it has less weight of atmosphere above it, and
people who go up in balloons often have great diffi-
culty in breathing, because the air is so thin and light.
In 1804 a Frenchman, named Gay-Lussac, went up
four miles and a half in a balloon, and brought down
some air; and he found that it was much less heavy
than the same quantity of air taken close down to the
earth, showing that it was much thinner, or rarer, as it
is called;* and when, in 1862, Mr. Glaisher and Mr.
Coxwell went up five miles and a half, Mr. Glaisher's
veins began to swell, his head grew dizzy, and he
fainted. The air was too thin for him to breathe
enough in at a time, and it did not press heavily
enough on the drums of his ears and the veins of his
body. He would have died if Mr. Coxwell had not
quickly let off some of the gas in the balloon, so that
it sank down into denser air.

AnTi now comes another very interesting question.
If the air gets less and less dense as it is farther from
the earth, where does it stop altogether? We cannot
go up to find out, because we should die long before
we reached the limit; and for a long time we had to
guess about how high the atmosphere probably was,
and it was generally supposed not to be more than fifty
miles. But lately, some curious bodies, which we

* 100 cubic inches near the earth weighed 31 grains, while the
same quantity taken at four and a half miles up in the air
weighed only 12 grains, or two-fifths of the weight.

THE AERIAL OCEAN IN WHICH WE LIVE. 63

should have never suspected would be useful to us in
this way, have let us into the secret of the height of
the atmosphere. These bodies are the meteors, or
falling stars.

Most people, at one time or another, have seen what
looks like a star shoot right across the sky, and dis-
appear. On a clear starlight night you may often see
one or more of these bright lights flash through the
air; for one falls on an average in every twenty min-
utes, and on the nights of August 9th and November
13th there are numbers in one part of the sky. These
bodies are not really stars ; they are simply stones or
lumps of metal flying through the air, and taking fire
by clashing against the atoms of oxygen in it. There
are great numbers of these masses moving round and
round the sun, and when our earth comes across their
path, as it does especially in August and November,
they dash with such tremendous force through the
atmosphere that they grow white-hot, and give out
light, and then disappear, melted into vapour. Every
now and then one falls to the earth before it is all
melted away, and thus we learn that these stones
contain tin, iron, sulphur, phosphorus, and other sub-
stances.

It is while these bodies are burning that they look
to us like falling stars, and when we see them we know
that they must be dashing against our atmosphere.
Now if two people stand a certain known distance,
say fifty miles, apart on the earth, and observe these
meteors and the direction in which they each see them
fall, they can calculate (by means of the angle between
the two directions) how high they are above them

64 THE FAIRY -LAND OF SCIENCE.

when they first see them, and at that moment they
must have struck against the atmosphere, and even
travelled some way through it, to become white-hot.
In this way we have learnt that meteors burst into
light at least 100 miles above the surface of the earth,
and so the atmosphere must be more than 100 miles
high.

Our next question is as to the weight of our aerial

ocean. You will easily understand that all this air

weighing down upon the earth

\ must be very heavy, even though

? it grows lighter as it ascends. The

^^_ 7 atmosphere does, in fact, weigh

^^ \ down upon land at the level of the

I ' sea as much as if a 15-pound weight

I \ I were put upon every square inch of

land. This little piece of linen

paper, which I am holding up,

measures exactly a square inch.

Fig. 13,— a square anj 35 jt ligg on the table, it is

rolninXekc! ^"^""S ^ ^^'g*^' "^ ^5 lbs. on its
lure. surface. But how, then, comes it

that I can lift it so easily? Why
am I not conscious of the weight?

To understand this j'ou must give all your atten-
tion, for it is important and at first not very easy to
grasp. You must remember, in the first place, that
the air is heavy because it is attracted to the earth, and
in the second place, that since air is elastic all the atoms
of it are pushing upward against this gravitation. And
so, at any point in air, as for instance the place where

THE AERIAL OCEAN IN WHICH WE LIVE. 65

the paper now is as I hold it up, I feel no pressure,
because exactly as much as gravitation is pulling the
air down, so much elasticity is resisting and pushing it
up. So the pressure is equal upward, downward, and
on all sides, and I can move the paper with equal ease
any way.

Even if I lay the paper on the table this is still true,
because there is always some air under it. If, how-
ever, I could get the air quite away from one side of
the paper, then the pressure on the other side would
show itself. I can do this by simply wetting the paper
and letting it fall on the table, and the water will
prevent any air from getting under it. Now see ! if
I try to lift it by the thread in the middle, 1 have
great difficulty, because the whole 15 pounds' weight
of the atmosphere is pressing it down. A still better
way of making the experiment is with a piece of
leather, such as the boys often amuse themselves with
in the streets. This piece of leather has been well
soaked. I drop it on the floor, and see ! it requires all
my strength to pull it up.* I now drop it on this stone
weight, and so heavily is it pressed down upon it
by the atmosphere that I can lift the weight without its
breaking away from it.

Have you ever tried to pick limpets off a rock ? If
so, you know how tight they cling. The limpet clings
to the rock just in the same way as this leather does
to the stone; the little animal exhausts the air inside

* In fastening the string to the leather the hole must be very
small and the knot as flat as possible, and it is even well to put
a small piece of kid under the knot. When I first made this ex-
periment, not having taken these precautions, it did not succeed
well, owing to air getting in through the hole.

66 THE FAIRY-LAND OF SCIENCE. ^H

its shell, and then it is pressed against the rock by the ^1

its shell, and then it is pressed against the rock by the
whole weight of the air above.

Perhaps you will wonder how it is that if we have
a weight of 15 lbs. pressing on every square inch of
our bodies, it does not
crush us. And, in-
deed, it amounts on the
whole to a weight of
about 15 tons upon the
body of a grown man.
It would crush us if it
were not that there are
gases and fluids inside
our bodies which press
outward and balance
the weight so that we
do not feel it at all.
This is why Mr. Glaisher's veins swelled and he
grew giddy in thin air. The gases and fluids inside his
body were pressing outward as much as when he was
below, but the air outside did not press so heavily, and
so all the natural condition of his body was dis-
turbed.

I hope we realize how heavily the air presses down
upon our earth, but it is equally necessary to under-
stand how, being elastic, it also presses upward ; and
we can prove this by a simple experiment, I fill
this tumbler with water, and keeping a piece of card
firmly pressed against it, I turn the whole upside-
down. When I now take my hand away you would
naturally expect the card to fall, and the water to be
spilt. But no! the card remains as if glued to the

Fic 14. — Soaked Ic
slane paper-i

THE AERIAL OCEAN IN WHICH WE UVE. 6/

tumbler, kept there entirely by the air pressing upward
against it.

And now we are almost prepared to understand
how we can weigh the invisible air. One more experi-
ment first. I have here (Fig. i6, p. 68) what is called
a U tube, because it is shaped like a large U. I pour
some water in it till it is about half full, and you will
notice that the water stands at the same height
in both arms of the tube (A, Fig. i6), because the
air presses on both surfaces alike. Putting my thumb
on one end I tilt the tube carefully, so as to make
the water run up to the end of one arm, and then turn
it back again (B, Fig. i6). But the water does not
now return to its even position, it remains up in
the arm on which my thumb
rests. Why is this ? Because
my thumb keeps back the
air from pressing at that end,
and the whole weight of the
atmosphere rests on the water
at c. And so we learn that
not only has the atmosphere
real weight, but we can see the
effects of this weight by mak-
ing it balance a column of
water or any other liquid. In

the case of the wetted leather we felt the weight of the
air, here we see its effects.

Now when we wish to see the weight of the air
we consult a barometer, which works really just in
the same way as the water in this tube. An ordi-
nary upright barometer is simply a straight tube of

THE FAIRY-LAND OF SCIENCE.

jiflass iillcd with mercury or quicksilver, and turned
ui)si(lc-(lown in a small cup of mercury (see B, Fig.

17). The tube is
^ ' i r ;*;^'*^^,^^^^ ,-^-w ^ ^^^^^^ more than

Ul 1 WjIL^ iliWfl 3^ inches long,

I i m^B^ jmrnmrn and though it is

I c .^Bfr^ quite full of mer-

^S^^ cury before it is

l''l(j. i^. — A, water in a U tube under
natural pressure of air; B, water
kept in one arm of the tube by
pri'HHure of the air being at the
open end only at r.

turned up (A), yet
directly it stands
in the cup the
mercury falls, till
there is a height
of about 30 inches between the surface of the mercury
in the cup C, and that of the mercury in the tube B.
As it falls it leaves an empty space above the mercury
at B which is called a vacuum, because it has no air in
it. Now, the mercury is under the same conditions as
the water was in the U tube, there is no pressure upon
it at B, while there is a pressure of 15 lbs. upon it in the
bowl, and therefore it remains held up in the tube.

But why will it not remain more than 30 inches
high in the tube? You must remember it is only
kept up in the tube at all by the air which presses on
the mercury in the cup. And that column of mercury
C B now balances the pressure of the air outside, and
presses down on the mercury in the cup at its mouth
just as much as the air does on the rest. So this cup
and tube act exactly like a pair of scales. The air out-
side is a thing to be weighed at one end as it presses
on the mercury, the column C B answers to the leaden
weight at the other end which tells you how heavy

THE AERIAL OCEAK IN WHICH IVE LIVE, 69

the air is. Now if the bore of this tube is made an
inch square, then the 30 inches of mercury in it weigh
exactly 15 lbs., and so we know that the weight of
the air is 15 lbs. upon ever>- square inch, but if the bore
of the tube is onlv half a
square inch, and there-
fore the 30 inches of
mercur)' only weigh 7^
lbs. instead of 15 lbs., the
pressure of the atmos-
phere will also be halved,
because it will onlv act
upon half a square inch
of surface, and for this
reason it will make no
difference to the height
of the mercurv whether
the tube be broad or nar-
row. Fig. 18 is a pic-
ture of the ordinary up-
right barometer ; the cup
of mercury in which the
tube stands is hidden in-
side the round piece of
wood A, and just at the
bottom of this round is a small hole B, through which
the air gets to the cup.

But now suppose the atmosphere grows lighter, as
it does when it has much damp in it. The barometer
will show this at once, because there will be less
weight on the mercury in the cup, therefore it will
not keep the mercury pushed so high up in the

Fig. 17. — Tube of mercury in-
verted in a basin of mercury.

Fig. r8.— Ordi-
nary upright
barometer.
A, wood cov-
ering cup of
mercury ; ~

THE FAIRY-LAND OF SCIENCE.

In other words, the mercury in the tube will
fall.

Let us suppose that one day the air
is so much lighter that it presses down
only with a weight of 14^ lbs. to the
square inch instead of 15 lbs. Then
the mercury would fall to 29 inches,
because each inch is equal to the
weight of half a pound. Now, when
the air is damp and very full of water-
vapour it is much lighter, and so when
the barometer falls we expect rain.
Sometimes, however, other causes make
the air light, and then, although the
barometer is low, no rain comes.

Again, if the air becomes heavier
the mercury is pushed up above 30 to
31 inches, and in this way we are able
to weigh the invisible air-ocean all over
the world, and tell when it grows lighter
or heavier. This, then, is the secret of
the barometer. We cannot speak of the
thermometer to-day, but I should like
to warn you in passing that it has noth-
ing to do with the weight of the air,
but only with heat, and acts in quite a
different way.

And now we have been so long
hole through hunting out, testing and weighing our
whichairacts. ^^^^ occan, that scarcely any time is
left us to speak of its movements or the pleasant

THE AERIAL OCEAN IN WHICH WE LIVE, 71

breezes which it makes for us in our country walks.
Did you ever try to run races on a very windy day?
Ah! then you feel the air strongly enough; how it
beats against your face and chest, and blows down
your throat so as to take your breath away ; and what
hard work it is to struggle against it! Stop for a
moment and rest, and ask yourself, what is the wind?
Why does it blow sometimes one way and sometimes
another, and sometimes not at all?

Wind is nothing more than air moving across the
surface of the earth, which as it passes along bends
the tops of the trees, beats against the houses, pushes
the ships along by their sails, turns the windmill, car-
ries off the smoke from cities, whistles through the
keyhole, and moans as it rushes down the valley.
What makes the air restless? why should it not lie
still all round the earth ?

It is restless because, as you will remember, its
atoms are kept pressed together near the earth by the
weight of the air above, and they take every oppor-
tunity, when they can find more room, to spread out
violently and rush into the vacant space, and this rush
we call a wind.

Imagine a great number of active schoolboys all
crowded into a room till they can scarcely move their
arms and legs for the crush, and then suppose all at
once a large door is opened. Will they not all come
tumbling out pell-mell, one over the other, into the hall
beyond, so that if you stood in their way you would
most likely be knocked down? Well, just this hap-
pens to the air-atoms; when they find a space before
them into which they can rush, they come on helter-

THE FAIRY-LAND OF SCIENCE.

skelter, with such force that you have great difficulty in
standing against them, and catch hold of something to
support you for fear you should be blown down.

But how come they to find any empty space to
receive them. To answer this we must go back
again to our little active invisible fairies the sunbeams.
When the sun-waves come pouring down upon the
earth they pass through the air almost without heating
it. But not so with the ground ; there they pass down
only a short distance and then are thrown back again.
And when these sun-waves come quivering back they
force the atoms of the air near the earth apart and
make it lighter ; so that the air close to the surface of
the heated ground becomes less heavy than the air
above it, and rises just? as a cork rises in water. You
know that hot air rises in the chimney ; for if you put
a piece of lighted paper on the fire it is carried up by
the draught of air, often even before it can ignite.
Now just as the hot air rises from the fire, so it rises
from the heated ground up into higher parts of the
atmosphere. And as it rises it leaves only thin air be-
hind it, and this cannot resist the strong cold air whose
atoms are struggling and trying to get free, and they
rush in and fill the space.

One of the simplest examples of wind is to be
found at the seaside. There in the daytime the land
gets hot under the sunshine, and heats the air, making
it grow light and rise. Meanwhile the sunshine on
the water goes down deeper, and so does not send
back so many heat-waves into the air; consequently
the air on the top of the water is cooler and heavier,
and it rushes in from over the sea to fill up the space

THE AERIAL OCEAN IN WHICH WE LIVE. 73

on the shore left by the warm air as it rises. This is
why the seaside is so pleasant in hot weather. During
the daytime a light sea-breese nearly always sets in
from the sea to the land.

When night comes, however, then the land loses its
heat very quickly, because it has not stored it up
and the land-air grows cold; but the sea, which has
been hoarding the sun-waves down in its depths, now
gives them up to the atmosphere above it, and the
sea-air becomes warm and rises. For this reason it
is now the turn of the cold air from the land to spread
over the sea, and you have a land-breeze blowing off
the shore.

Again, the reason why there are such steady winds,
called the trade winds, blowing toward the equator,
is that the sun is very hot at the equator, and hot air
is always rising there and making room for colder air
to rush in. We have not time to travel farther with
the moving air, though its journeys are extremely
interesting ; but if, when you read about the trade and
other winds, you will always picture to yourselves
warm air made light by heat rising up into space and
cold air expanding and rushing in to fill its place, I
can promise you that you will not find the study of
aerial currents so dry as many people imagine it
to be.

We are now able to form some picture of our aerial
ocean. We can imagine the active atoms of oxygen
floating in the sluggish nitrogen, and being used up in
every candle-flame, gas-jet and fire, and in the breath
of all living beings ; and coming out again tied fast to

THE FAIRY-LAND OF SCIENCE.

atoms of carbon and making carbonic acid. Then we
can turn to trees and plants, and see them tearing these
two apart again, holding the carbon fast and sending
the invisible atoms of oxygen bounding back again
into the air, ready to recommence work. We can
picture all these air-atoms, whether of oxygen or nitro-
gen, packed close together on the surface of the earth,
and lying gradually farther and farther apart, as they
have less weight above them, till they become so scat-
tered that we can only detect them as they rub against
the flying meteors which flash into light. We can feel
this great weight of air pressing the limpet on to the
rock; and we can see it pressing up the mercury in
the barometer and so enabling us to measure its
weight. Lastly, every breath of wind that blows past
us tells us how this aerial ocean is always moving to
and fro on the face of the earth ; and if we think for a
moment how much bad air and bad matter it must
carry away, as it goes from the crowded cities to be
purified in the country, we can see how, in even this
one way alone, it is a great blessing to us.

Yet even now we have not mentioned many of the
beauties of our atmosphere. It is the tiny particles
floating in the air which scatter the light of the sun
so that it spreads over the whole country and into
shady places. The sun's rays always travel straight
forward; and in the moon, where there is no atmos-
phere, there is no light anywhere except just where
the rays fall. But on our earth the sun-waves hit
against the myriads of particles in the air and glide
off them into the corners of the room or the recesses
of a shady lane, and so we have light spread before

THE AERIAL OCEAN IN WHICH WE LIVE. 75

US wherever we walk in the daytime, instead of those
deep black shadows which we can see through a tele-
scope on the face of the moon.

Again, it is electricity playing in the air-atoms in
the upper parts of the atmosphere, where the air is
very thin and rare, which gives us the beautiful light-
ning and the grand aurora borealis, and even the
twinkling of the stars is produced entirely by minute
changes in the air. If it were not for our aerial ocean
the stars would stare at us sternly, instead of smiling
with the pleasant twinkle-twinkle which we have all
learned to love as little children.

All these questions, however, we must leave for
the present; only I hope you will be eager to read
about them wherever you can, and open your eyes to
learn their secrets. For the present we must be con-
tent if we can even picture this wonderful ocean of
gas spread round our earth, and some of the work it
does for us.

We said in the last lecture that without the sun-
beams the earth would be cold, dark, and frost-ridden.
With sunbeams, but without air, it would indeed have
burning heat, side by side with darkness and ice, but
it could have no soft light. Our planet might look
beautiful to others, as the moon does to us, but it
could have comparatively few beauties of its own.
With the sunbeams and the air, we see it has much
to make it beautiful. But a third worker is wanted
before our planet can revel in activity and life. This
worker is water; and in the next lecture we shall
learn something of the beauty and the usefulness of
the " drops of water " on their travels.

Y^ are going to
spend an hour
to-day in fol-
lowing a drop
of water on its travels. If I dip my finger in this
basin of water and lift it up again, I bring with it

A DROP OF WATER. yy

a small glistening drop out of the body of water be-
low,, and hold it before you. Tell me, have you any
idea where this drop has been? what changes it has
undergone, and what work it has been doing during
all the long ages that water has lain on the face of
the earth? It is a drop now, but it was not so before
I lifted it out of the basin; then it was part of a sheet
of water, and will be so again if I let it fall. Again,
if I were to put this basin on the stove till all the
water had boiled away, where would my drop be then?
Where would it go? What forms will it take before
it reappears in the rain-cloud, the river, or the spark-
ling dew?

These are questions we are going to try to answer
to-day; and first, before we can in the least under-
stand how water travels, we must call to mind what
we have learned about the sunbeams and the air. We
must have clearly pictured in our imagination those
countless sun-waves which are for ever crossing space,
and especially those larger and slower undulations, the
dark heat-waves; for it is these, you will remember,
which force the air-atoms apart and make the air
light, and it is also these which are most busy in
sending water on its travels. But not these alone.
The sun-waves might shake the water-drops as much
as they liked, and turn them into visible vapour, but
they could not carry them over the earth if it were not
for the winds and currents of that aerial ocean which
bears the vapour on its bosom, and wafts it to different
regions of the world.

Let us try to understand how these two invisible
workers, the sun-waves and the air, deal with the drops

THE FAIRY-LAND OF SCIENCE,

of water. I have here a kettle (Fig. 19, p. 79) boiling
over a spirit-lamp, and I want you to follow minutely
v/hat is going on in it. First, in the flame of the lamp,
atoms of the spirit drawn up from below are clashing
with the oxygen-atoms in the air. This, as you know,
causes heat-waves and light-waves to move rapidly
all round the lamp. The light waves cannot pass
through the kettle, but the heat-waves can, and as
they enter the water inside they agitate it violently.
Quickly, and still more quickly, the particles of water
near the bottom of the kettle move to and fro and are
shaken apart; and as they become light they rise
through the colder water, letting another layer come
down to be heated in its turn. The motion grows
more and more violent, making the water hotter and
hotter, till at last the particles of which it is com-
posed fly asunder, and escape as invisible vapour. If
this kettle were transparent you would not see any
steam above the water, because it is in the form of an
invisible gas. But as the steam comes out of the
mouth of the kettle you see a cloud. Why is this?
Because the vapour is chilled by coming out into the
cold air, and condenses round the minute particles of
dust floating in the air, forming into tiny, tiny drops
of water, to which Dr. Tyndall has given the sugges-
tive name of water-dust. If you hold a plate over the
steam you can catch these tiny drops, though they will
run into one another almost as you are catching them.
The clouds you see floating in the sky are made of
exactly the same kind of water-dust as the cloud from
the kettle, and I wish to show you that this is also
really the same as the invisible steam within the kettle.

A DROP OF WATER.

I will do so by an experiment suggested by Dr. Tyn-
dall. Here is another spirit-lamp, which I will hold
under the cloud of steam — see! the cloud disappears!
As soon as the water-dust is heated the heat-waves

Fig. 19.

scatter it again into invisible particles, which float
away into the room. Even without the spirit-lamp,
you can convince yourself that water-vapour may be
invisible ; for close to the mouth of the kettle you will
see a short blank space before the cloud begins. In
this space there must be steam, but it is still so hot
that you cannot see it; and this proves that heat-
waves can so shake water apart as to carry it away in-
visibly right before your eyes.

Now, although we never see any water travelling
from our earth up into the skies, we know that it goes
there, for it comes down again in rain, and so it must
go up invisibly. But where does the heat come from
which makes this water invisible? Not from below,
as in the case of the kettle, but from above, pouring
down from the sun. Wherever the sun-waves touch
the rivers, ponds, lakes, seas, or fields of ice and snow

80 THE FAIRY-LAND OF SCIENCE.

Upon our earth, they carry off invisible water-vapour.
They dart down through the top layers of the water,
and shake the water-particles forcibly apart; and in
this case the drops fly asunder more easily and before
they are so hot, because they are not kept down
by a great weight of water above,* as in the kfettle,
but find plenty of room to spread themselves out
in the gaps between the air-atoms of the atmos-
phere.

Can you imagine these water-particles, just above
any pond or lake, rising up and getting entangled
among the air- atoms? They are very light, much
lighter than the atmosphere; and so, when a great
many of them are spread about in the air which lies
just over the pond, they make it much lighter than
the layer of air above, and so help it to rise, while
the heavier layer of air comes down ready to take up
more vapour.

In this way the sun-waves and the air carry off
water every day, and all day long, from the top of
lakes, rivers, pools, springs, and seas, and even from
the surface of ice and snow. Without any fuss or
noise or sign of any kind, the water of our earth is
being drawn up invisibly into the sky.

It has been calculated that in the Indian Ocean
three-quarters of an inch of water is carried off from
the surface of the sea in one day and night; so that
as much as 22 feet, or a depth of water about twice
the height of an ordinary room, is silently and in-
visibly lifted up from the whole surface of the ocean
in one year. It is true this is one of the hottest parts
of the earth, where the sun-waves are most active;

A DROP OF WATER. 8l

but even in our own country many feet of water are
drawn up in the summer-time.

What, then, becomes of all this water? Let us fol-
low it as it struggles upward to the sky. We see it in
our imagination first carrying layer after layer of air
up with it from the sea till it rises far above our heads
and above the highest mountains. But now, call to
mind what happens to the air as it recedes from the
earth. Do you not remember that the air-atoms are
always trying to fly apart, and are only kept pressed
together by the weight of air above them? Well, as
this water-laden air rises up, its particles, no longer so
much pressed together, begin to separate, and as all
work requires an expenditure of heat, the air becomes
colder, and then you know at once what must happen
to the invisible vapour — it will form into tiny water-
drops, like the steam from the kettle. And so, as the
air rises and becomes colder, the vapour gathers into
visible masses, and we can see it hanging in the sky,
and call it clouds. When these clouds are highest they
are about ten miles from the earth, but when they are
made of heavy drops and hang low down, they some-
times come within a mile of the ground, or even lower.
When they rest upon its surface we call them fog and
mist.

Look up at the clouds as you go home, and think
that the water of which they are made has all been
drawn up invisibly through the air. Not, however,
necessarily here where we live, for we have already
seen that air travels as wind all over the world, rushing
in to fill spaces made by rising air wherever they occur,
and so these clouds may be made of vapour collected

82 THE FAIRT-LAND OF SCIENCE.

in the Mediterranean, or in the Gulf of Mexico off
the coast of America, or even, if the wind is from the
north, of chilly particles gathered from the surface
of Greenland ice and snow, and brought here by the
moving currents of air. Only, of one thing we
may be sure, that they come from the water of our
earth.

Sometimes, if the air is warm, these water- particles
may travel a long way without ever forming into
clouds; and on a hot, cloudless day the air is often
very full of invisible vapour. Then, if a cold wind
comes sweeping along, high up in the sky, and chills

Fig. 20. — Clouds formed by ascending vapour as it cnlers cold

this vapour, it forms into great bodies of water-dust
clouds, and the sky is overcast. At other times clouds
hang lazily in a bright sky, and these show us that
just where they are (as in Fig. 20) the air is cold and
turns the invisible vapour rising from the ground into
visible water-dust, so that exactly in those spaces we
see it as clouds. Such clouds form often on a warm,
still summer's day, and they are shaped like masses
of wool, ending in a straight line below. They are
not merely hanging in the sky, they are really resting

A DROP OF WATER.

upon a tall column of invisible vapour which stretches
right up from the earth; and that straight line under
the clouds marks the place where the air becomes cold
enough to turn this invisible vapour into visible drops
of water.

And now, suppose that while these or any other
kind of clouds are overhead, there comes along either
a very cold wind, or a wind full of vapour. As it
passes through the clouds, it makes them very full of
water, for, if it chills them, it makes the water-dust
draw more closely together; or, if it brings a new load
of water-dust, the air is fuller than it can hold. In
either case a number of water-particles are set free,
and our fairy force " cohesion " seizes upon them at
once and forms them into large water-drops. Then
they are much heavier than the air, and so they can
float no longer, but down they come to the earth in a
shower of rain.

There are other ways in which the air may be
chilled, and rain made to fall, as, for example, when
a wind laden with moisture strikes against the cold
tops of mountains. Thus the Khasia Hills in India,
which face the Bay of Bengal, chill the air which
crosses them on its way from the Indian Ocean. The
wet winds are driven up the sides of the hills, the air
expands, and the vapour is chilled, and forming into
drops, falls in torrents of rain. Sir J. Hooker tells us
that as much as 500 inches of rain fell in these hills
in nine months. That is to say, if you could measure
off all the ground over which the rain fell, and spread
the whole nine months' rain over it, it would make a
lake 500 inches, or more than 40 feet deep! You will

84 THE FAIRY'LAND OF SCIENCE.

not be surprised that the country on the other side of
those hills gets hardly any rain, for all the water has
been taken out of the air before it comes there. Again
for example in England, the wind comes to Cumber-
laiul and Westmoreland over the Atlantic, full of va-
pour, and as it strikes against the Pennine Hills it
shakes off its watery load ; so that the lake district is
the most rainy in England, with the exception perhaps
i^f Wales, where the high mountains have the same
effect.

In this wav, from different causes, the water of
which the sun has robbed our rivers and seas, comes
back to us, after it has travelled to various parts of
the world, floating on the bosom of the air. But it
<loes not always fall straight back into the rivers and
seas again ; a large part of it falls on the land, and has
to trickle down slopes and into the earth, in order to
get back to its natural home, and it is often caught on
its way before it can reach the great waters.

do to any piece of ground which is left wild and
untouched, you will find it covered with grass, weeds,
and other plants; if you dig up a small plot you will
find innumerable tiny roots creeping through the
ground in every direction. Each of these roots has
a s]>onge-like mouth by which the plant takes up
water. Now, imagine rain-drops falling on this plot
of ground and sinking into the earth. On every side
they will find rootlets thirsting to drink them in, and
they will be sucked up as if by tiny sponges, and
drawn into the plants, and up the stems to the leaves.
1 1 ere, as we shall see in Lecture VII, they are worked

A DROP OF WATER. 8$

Up into food for the plant, and only if the leaf has
more water than it needs, some drops may escape at
the tiny openings under the leaf, and be drawn up
again by the sun-waves as invisible vapour into the air.

Again, much of the rain falls on hard rock and
stone, where it cannot sink in, and then it lies in pools
till it is shaken apart again into vapour and carried off
in the air. Nor is it idle here, even before it is car-
ried up to make clouds. We have to thank this in-
visible vapour in the air for protecting us from the
burning heat of the sun by day and intolerable frost
by night.

Let us for a moment imagine that we can see all
that we know exists between us and the sun. First,
we have the fine ether across which the sunbeams
travel, beating down upon our earth with immense
force, so that in the sandy desert they are like a burn-
ing fire. Then we have the coarser atmosphere of oxy-
gen and nitrogen atoms hanging in this ether, and
bending the minute sun-waves out of their direct path.
But they do very little to hinder them on their way,
and this is why in very dry countries the sun's heat is
so intense. The rays beat down mercilessly, and noth-
ing opposes them. Lastly, in damp countries we have
the larger but still invisible particles of vapour hang-
ing about among the air-atoms. Now, these watery
particles, although they are very few (only about one
twenty-fifth part of the whole atmosphere), do hinder
the sun-waves. For they are very greedy of heat, and
though the light-waves pass easily through them, they
catch the heat-waves and use them to help themselves
to expand. And so, when there is invisible vapour in

86 THE FAIRY-LAND OF SCIENCE.

the air, the sunbeams come to us deprived of some ol
their heat-waves, and we can remain in the sunshine
without suffering from the heat.

This is how the water-vapour shields us by day,
but by night it ic still more useful. During the day
our earth and the air near it have been storing up the
heat which has been poured down on them, and at
night, when the sun goes down, all this heat begins to
escape again. Now, if there were no vapour in the air,
this heat would rush back into space so rapidly that
the ground would become cold and frozen even on a
summer's night, and all but the most hardy plants
would die. But the vapour which formed a veil against
the sun in the day, now forms a still more powerful
veil against the escape of the heat by night. It shuts
in the heat-waves, and only allows them to make their
way slowly upward from the earth — thus producing
for us the soft, balmy nights of summer and prevent-
ing all life being destroyed in the winter.

Perhaps you would scarcely imagine at first that it
is this screen of vapour which determines whether or
not we shall have dew upon the ground. Have you
ever thought why dew forms, or what power has been
at work scattering the sparkling drops upon the grass ?
Picture to yourself that it has been a very hot sum-
mer's day, and the ground and the grass have been
well warmed, and that the sun goes down in a clear
sky without any clouds. At once the heat-waves
which have been stored up in the ground, bound back
into the air, and here some are greedily absorbed by
the vapour, while others make their way slowly up-
ward. The grass, especially, erives out these heat-waves

A DROP OF WATER. 87

very quickly, because the blades, being very thin, are
almost all surface. In consequence of this they part
with their heat more quickly than they can draw it
up from the ground, and become cold. Now, the air
lying just above the grass is full of invisible vapour,
and the cold of the blades, as it touches them, chills
the water-particles, and they are no longer able to hold
apart, but are drawn together into drops on the sur-
face of the leaves.

We can easily make artificial dew for ourselves. I
have here a bottle of ice which has been kept outside
the window. When I bring it into the warm room a
mist forms rapidly outside the bottle. This mist is
composed of water-drops, drawn out of the air of the
room, because the cold glass chilled the air all round
it, so that it gave up its invisible water to form dew-
drops. Just in this same way the cold blades of grass
chill the air lying above them, and steal its vapour.

But try the experiment, some night when a heavy
dew is expected, of spreading a thin piece of muslin
over some part of the grass, supporting it at the four
corners with pieces of stick so that it forms an awn-
ing. Though there may be plenty of dew on the
grass all round, yet under this awning you will find
scarcely any. The reason of this is that the muslin
checks the heat-waves as they rise from the grass,
and so the grass-blades are not chilled enough to draw
together the water-drops on their surface. If you
walk out early in the summer mornings and look at
the fine cobwebs flung across the hedges, you will see
plenty of drops on the cobwebs themselves sparkling
like diamonds ; but underneath on the leaves there will

88 THE FAIRY-LAND OF SCIENCE.

be none, for even the delicate cobweb has been strong
enough to shut in the heat-waves and keep the leaves
warm.

Again, if you walk off the grass on to the gravel
path, you find no dew there. Why is this? Because
the stones of the gravel can draw up heat from the
earth below as fast as they give it out, and so they
are never cold enough to chill the air which touches
them. On a cloudy night also you will often find
little or no dew even on the grass. The reason of this
is that the clouds give back heat to the earth, and
so the grass does not become chilled enough to draw
the water-drops together on its surface. But after
a hot, dry day, when the plants are thirsty and there
is little hope of rain to refresh them, then they are
able in the evening to draw the little drops from the
air and drink them in before the rising sun comes
again to carry them away.

But our rain-drop undergoes other changes stran-
ger than these. Till now we have been imagining it to
travel only where the temperature is moderate enough
for it to remain in a liquid state as water. But sup-
pose that when it is drawn up into the air it meets with
such a cold blast as to bring it to the freezing point.
If it falls into this blast when it is already a drop, then
it will freeze into a hailstone, and often on a hot sum-
mer's day we may have a severe hailstorm, because
the rain-drops have crossed a bitterly cold wind as
they were falling, and have been frozen into round
drops of ice.

But if the water-vapour reaches the freezing air

I DROP OF WA TER.

while it is still an invisible gas, and before it has been
drawn into a drop, then its history is very different.
The ordinary force of cohesion has then no power over
the particles to make them into watery globes, but its
place is taken by the fairy process of " crystallization,"
and they are formed into beautiful white fJakes, to fall
in a snow-shower. I
want you to picture
this process to your-
selves, for if once you
can take an interest in
the wonderful power of
nature to buiid up crys-
tals, you will be as-
tonished how often you
will meet with in-
stances of it, and what
pleasure it will add to
your life.

The particles of
nearly all substances,
when left free and not
hurried, can build
themselves into crys-
tal forms. If you melt
salt in water and then
let all the water evapo-
rate slowly, you will

get salt-crystals — beautiful cubes of transparent salt
all built on the same pattern. The same is true of
sugar ; and if you will look at the spikes of an ordinary
stick of rock-candy, such as I have here, you will see

21. — A piece ciI roclt- candy,
photographed, of ihe natural

THE FAIRY-LAND OF SCIENCE.

the kind of crystals which sugar forms. You may
even pick out such shapes as these from the common
crystallized brown sugar in the sugar basin, or see
them with a magnifying glass on a lump of white
sugar.

But it is not only easily melted substances such as
sugar and salt which form crystals. The beautiful
stalactite grottos are all made of crystals of lime.
Natural diamonds are crystals of carbon, made inside
the earth.* Rock-crystals, which you know probably
under the name of Cape May or California diamonds,
are crystallized quartz; and so, with slightly different
colourings, are agates, opals, jasper, cairngorms, and
many other precious stones. Iron, copper, gold, and
sulphur, when melted and cooled slowly build them-
selves into crystals, each of their own peculiar form,
and we see that there is here a wonderful order, such
as we should never have dreamed of, if we had not
proved it. If you possess a microscope you may
watch the growth of crystals yourself by melting some
common powdered nitre in a little water till you find
that no more will melt in it. Then put a few drops
of this water on a warm glass slide and place it under
the microscope. As the drops dry you will see the
long transparent needles of nitre forming on the glass,
and notice how regularly these crystals grow, not by
taking food inside like living beings, but by adding
particle to particle on the outside evenly and regu-
larly.

Can we form any idea why the crystals build them-

* It is possible to make diamonds artificially, but they are
very small.

A DROP OF WATER,

selves up so systematically? Dr. Tyndall says we can,
and I hope by the help of these small bar magnets
to show you how he explains it. These little pieces of
steel, which I hope you can see lying on this white
cardboard, have been rubbed along a magnet until
they have become magnets themselves, and I can at-
tract and lift up a needle with any one of them. But
if I try to lift one bar with another, I can only do
it by bringing certain ends together. I have tied a
piece of red cotton (c. Fig. 22) round one end of each

Fig. 22. — Bar magnets attracting and repelling each other.
<:, Cotton tied round positive end of the magnet.

of the magnets, and if I bring two red ends together
they will not cling together but roll apart. If, on the
contrary, I put a red end against an end where there
is no cotton, then the two bars cling together. This
is because every magnet has two poles or points which
are exactly opposite in character, and to distinguish
them one is called the positive pole and the other
the negative pole. Now when I bring two red ends,
that is, two positive poles, together they drive each

THE FAIRY^LAND OF SCIENCE.

Other away. See! the magnet I am not holding runs
away from the other. But if I. bring a red end and
a black end, that is, a positive and a negative end, to-
gether, then they are attracted and cling. I will make
a triangle (A, Pig. 22) in which a black end and a
red end always come together, and you see the triangle
holds together. But now if I take off the lower bar
and turn it (B, Fig. 22) so that two red ends and two
black ends come together, then this bar actually rolls
back from the others down the cardboard. If I were to
break these bars into a thousand pieces, each piece
would still have two poles, and if they were scattered
about near each other in such a way that they were
quite free to move, they would arrange themselves
always so that two different poles came together.

You may not perhaps be able to easily obtain bar
magnets, but you may easily repeat these experiments
at home, and others even more interesting, with the
help of a toy horseshoe magnet, which almost any child
can get, a glass or bowl of water, and several sewing
needles. Rub the needles along the magnet and they
themselves will become magnets. Hold a needle par-
allel to the surface of the water and very near it. Drop
the needle, and it will float like a straw. This seems
strange, for the metal of which the needle is made is
much heavier than water, but a thin coat of air clings
to the polished steel, and the needle is too light to break
through it to the water. If the needle is not perfectly
dry the air will not cling to it, and it will sink. Float-
ing upon the surface of the water it will place itself
with one end pointing north and the other south. In
other words, it will be a compass.

A DROP OF WATER.

Picture to yourselves that all the particles of those
substances which form crystals have poles like our
magnets, or your needles, then you can imagine that
Avhen the heat which held them apart is withdrawn and
the particles come very near together, they will ar-
range themselves according to the attraction of their
poles and so build up regular and beautiful patterns.

So, if we could travel up to the clouds where this
fairy power of crystallization is at work, we should

Flc. 23. — Snow-cryslals.

find the particles of water -vapour in a freezing atmos-
phere being built up into minute solid crystals of
snow. It you go out after a snow-shower and search
carefully, you will see that the snow-flakes are not
mere lumps of frozen water, but beautiful six-pointed
crystal stars, so white and pure that when we want to
speak of anything being spotlessly white, you say

THE FAIRY-LAND OF SCIENCE.

that it is " white as snow." Some of these crystals
are simply flat slabs with six sides, others are stars
with six rods or spikes springing from the centre,
others with six spikes each formed like a delicate fern.
No less than a thousand different forms of delicate
crystals have been found among snow-flakes, but
though there is such a great variety, yet they are all
built on the six-sided and six-pointed plan, and are
all rendered dazzlingly white by the reflection of the
light from the faces of the crystals and the tiny air-
bubbles built up within them. This, you see, is why,
when the snow melts, you have only a little dirty water
in your hand; the crystals are gone and there are no
more air-bubbles held prisoners to act as looking-
glasses to the light. Hoar-frost is also made up of
tiny water-crystals, and is nothing more than frozen
dew hanging on the blades of grass and from the trees.

But how about ice? Here, you will say, is frozen
water, and yet we see no crystals, only a clear trans-
parent mass. Here, again. Dr. Tyndall helps us. He
says (and as I have proved it true, so may you for
yourselves, if you will) that if you take a magnifying
glass, and look down on the surface of ice on a sunny
day, you will see a number of dark, six-sided stars,
looking like flattened flowers, and in the centre of each
a bright spot. These flowers, which are seen when
the ice is melting, are our old friends the crystal stars
turning into water, and the bright spot in the middle
is a bubble of empty space, left because the watery
flower does not fill up as much room as the ice of the
crystal star did.

And this leads us to notice that ice always takes

A DROP OF WA TEH.

Up more room than water, and that this is the reason
why our water-pipes burst in severe frosts; for as the
water freezes it expands with great force, and the pipe
is cracked, and then when the thaw comes on, and
the water melts again, it pours through tlie crack it
has made.

It is not difficult to understand why ice should take
more room; for we know that if we were to try to
arrange bricks end to end in star-like shapes, we must

king i<

leave some spaces between, and could not pack them
so closely as if they lay side by side. And so, when
this giant force of crystallization constrains the atoms
of frozen water to grow into star-like forms, the solid
mass must fill more room than the liquid water, and
when the star melts, this space reveals itself to us
in the bright spot of the centre.

We have now seen our drop of water under all its
various forms of invisible gas, visible steam, cloud.

^ vve 1

^h various

96 THE FAIRY-LAND OF SCIENCE.

dew, hoarfrost, snow, and ice, and we have only time
shortly to see it on its travels, not merely up and down,
as hitherto, but round the world.

We must first go to the sea as the distillery, or the
place from which water is drawn up invisibly, in its
purest state, into the air; and we must go chiefly to
the seas of the tropics, because here the sun shines
most directly all the year round, sending heat-waves to
shake the water-particles asunder. It has been found
by experiment that, in order to turn i lb. of water into
vapour, as much heat must be used as is required to
melt 5 lbs. of iron; and if you consider for a moment
how difficult iron is to melt, and how we can keep an
iron poker in a hot fire and yet it remains solid, this
will help you to realize how much heat the sun must
pour down in order to carry off such a constant supply
of vapour from the tropical seas.

Now, when all this vapour is drawn up into the air,
we know that some of it will form into clouds as it
gets chilled high up in the sky, and then it will pour
down again in those tremendous floods of rain which
occur in the tropics.

But the sun and air will not let it all fall down at
once, and the winds which are blowing from the equa-
tor to the poles carry large masses of it away with
them. Then, as you know, it will depend on many
things how far this vapour is carried. Some of it,
chilled by cold blasts, or by striking on cold moun-
tain tops, as it travels northward, will fall in rain in
Europe and Asia, while that which travels southward
may fall in South America, Australia, or New Zealand,
or be carried over the sea to the South Pole. Wher-

A DROP OF WATER.

ever it falls on the land as rain, and is not used by
plants, it will do one of two things; either it will run
down in streams and form brooks and rivers, and so
at last find its way back to the sea, or it will sink
deep in the earth till it comes upon some hard rock
through which it cannot get, and then, being hard
pressed by the water coming on behind, it will rise up
again through cracks, and come to the surface as a
spring. These springs, again, feed rivers, sometimes
above-ground, sometimes for long distances under-
ground; but one way or another at last the whole
drains back into the sea.

But if the vapour travels on till it reaches high
mountains in cooler lands, such as the mountains in
Alaska; or is carried to the poles and to such countries
#s as Greenland or the Antarctic Continent, then it will
■N come down as snow, forming immense snow-fields.
^ And here a curious change takes place in it. If you
^ make an ordinary snowball and work it firmly to-
gether, it becomes very hard, and if you then press it
forcibly into a mould you can turn it into transparent
ice. And in the same way the snow which falls in
Greenland and on the high mountains of Alaska be-
comes very firmly pressed together, as it slides down
into the valleys. It is like a crowd of people passing
from a broad thoroughfare into a narrow street. As
the valley grows narrower and narrower the great
mass of snow in front cannot move down quickly,
while more and more is piled up by the snowfall be-
hind, and the crowd and crush grow denser and denser.
In this wav the snow^j^OTejsed "togejther till the air
that was hidden v^^si^f^tdls, ai^^^@fek gave it its

< LO LU 1': :- jJ ^ h . > • ^^ • • , . A

-O- :>■]

THE FAIRY-LAND OF SCIENCE,

beautiful whiteness, is all pressed out, and the snow-
crystals themselves are squeezed into one solid mass
of pure, transparent ice.

Then we have what is called a " glacier," or river of
ice, and this solid river comes creeping down till, in
Greenland, it reaches the edge of the sea. There it
is pushed over the brink of the land, and large pieces
snap off, and we have " icebergs." These icebergs —
made, remember, of the same water which was first
drawn up from the tropics — float on the wide sea, and
melting in its warm currents, topple over and over *
till they disappear and mix with the water, to be car-
ried back again to the warm ocean from which
they first started. In Switzerland the glaciers cannot
reach the sea, but they move down into the valleys
till they come to a warmer region, and there the end
of the glacier melts, and flows away in a stream. The
Rhone and many other rivers are fed by the glaciers
of the Alps ; and as these rivers flow into the sea, our
drop of water again finds its way back to its home.

But when it joins itself in this way to its com-
panions, from whom it was parted for a time, does
it come back clear and transparent as it left them?
From the iceberg it does indeed return pure and clear ;
for the fairy Crystallization will have no impurities,
not even salt, in her ice-crystals, and so as they melt
they give back nothing but pure water to the sea. Yet
even icebergs bring down earth and stones frozen into

* A floating iceberg must have about eight times as much ice
under the water as it has above, and therefore, when the lower
part melts in a warm current, the iceberg loses its balance and
tilts over, so as to rearrange itself round the centre of gravity.

A DROP OF WATER.

the bottom of the ice, and so they feed the sea with
mud.

Yet the drops of water in rivers are by no means
as pure as when they rose up into the sky. We shall
see in the next lecture that rivers not only carry down
sand and mud all along their course, but also contain
solid matter such as salt, lime, iron, and flint, dis-
solved in the clear water, just as sugar is dissolved,
without our being able to see it. The water, too,
which has sunk down into the earth, takes up much
matter as it travels along. You all know that the
water you drink from a spring is very different from
rain-watef, and you will often find a hard crust at
the bottom of kettles and in boilers, which is formed
of the carbonate of lime which is driven out of the
clear water when it is boiled. The water has become
" hard " in consequence of having picked up and dis-
solved the carbonate of lime on its way through the
earth, just in the same way as water would become
sweet if you poured it through a sugar-cask. You
will also have heard of iron-springs, sulphur-springs,
and salt-springs, which come out of the earth, even
if you have never tasted any of them, and the water
of all these springs finds its way back at last to the
sea.

And now, can you understand why sea-water
should taste salt and bitter? Every drop of water
which flows from the earth to the sea carries some-
thing with it. Generally, there is so little of any sub-
stance in the water that we cannot taste it, and we
call it pure water; but the purest of spring or river-
water has always some solid matter dissolved in it.

^ v\^v>ri w

lOO THE FAIRY-LAND OF SCIENCE.

and all this goes to the sea. Now, when the sun-
waves come to take the water out of the sea again,
they will have nothing but the pure water itself; and
so all these salts and carbonates and other solid sub-
stances are left behind, and we taste them in sea-
water.

S.~»me day, when you are at the seaside, take some
' set it over a fire till a great deal has sim-
mered ^<.Aiv*.y away, and the liquid is very thick. Then
take a drop of this liquid, and examine it under a
microscope. As it dries up gradually, you will see a
number of crystals forming, some square — and these
will be crystals of ordinary salt; some oblong — these
will be crystals of gypsum or alabaster; and others
of various shapes. Then, when you see how much
matter from the land is contained in sea-water, you
will no longer wonder that the sea is salt; on the
contrary, you will ask, Why does it not grow Salter
every year?

The answer to this scarcely belongs to our history
of a drop of water, but I must just suggest it to you.
In the sea are numbers of soft-bodied animals, like
the jelly animals which form the coral, which require
hard material for their shells or the solid branches on
which they live, and they are greedily watching for
these atoms of lime, of flint, of magnesia, and of other
substances brought down into the sea. It is with
lime and magnesia that the tiny chalk-builders form
their beautiful shells, and the coral animals their skele-
tons, while another class of builders use the flint; and
when these creatures die, their remains go to form
fresh land at the bottom of the sea; and so, though

A DROP OF WATER. iqi

the earth is being washed away by the rivers and
springs it is being built up again, out of the same
materials, in the depths of the great ocean.

And now we have reached the end of the travels of
our drop of water. We have seen it drawn up by the
fairy "heat," invisible into the sky; there fairy "co-
hesion " seized it, and formed it into water-drons, "^nd
the giant, " gravitation," pulled it down t
earth. Or, if it rose to freezing regions, i.ic fairy of
" crystallization " built it up into snow-crystals, again
to fall to the earth, and either to be melted back into
water by heat, or to slide down the valleys by force
of gravitation, till it became squeezed into ice. We
have detected it, when invisible, forming a veil round
our earth, and keeping off the intense heat of the sun's
rays by day, or shutting it in by night. We have seen
it chilled by the blades of grass, forming sparkling
dew-drops or crystals of hoarfrost, glistening in the
early morning sun; and we have seen it in the dark
underground, being drunk up greedily by the roots
of plants. We have started with it from the tropics,
and travelled over land and sea, watching it forming
rivers, or flowing underground in springs, or moving
onward to the high mountains or the poles, and com-
ing back again in glaciers and icebergs. Through all
this, while it is being carried hither and thither by
invisible power, we find no trace of its becoming worn
out, or likely to rest from its labours. Ever onward it
goes, up and down, and round and round the world,
taking rtiany forms, and performing many wonderful
feats. We have seen some of the work that it does,
in refreshing the air, feeding the plants, giving us

I02 THE FAIRY-LAND OF SCIENCE.

clear, sparkling water to drink, and carrying matter
to the sea; but besides this, it does a wonderful work
in altering all the face of our earth. This work we
shall consider in the next lecture, on " The two great
Sculptors — Water and Ice."

THE TWO GREAT SCULPTORS. 103

r last lecture we saw that

water can exist in three

•^ forms: — 1st, as an invisible

vapour; and, as liquid water; 3rd, as solid snow

and ice.

To-day we are going to take the two last of these

I04

THE FAIRY-LAND OF SCIENCE.

torms, water and ice, and speak of them as sculp-
tors.

To understand whv thev deserve this name we
must first consider what the work of a sculptor is. If
you go into a statuar)* yard you will find there large
blocks of granite, marble, and other kinds of stone,
hewn roughly into different shapes ; but if you pass
into the studio, where the sculptor himself is at work,
you will find beautiful statues, more or less finished;
and you will see that out of rough blocks of stone he
has been able to cut images which look like living
forms. You can even see by their faces whether they
are intended to be sad, or thoughtful, or gay, and by
their attitude whether they are writhing in pain, or
dancing with joy, or resting peacefully. How has all
this history been worked out from the shapeless stone?
It has been done by the sculptor s chisel. A piece
chipped off here, a wrinkle ait there, a smooth sur-
face rounded off in another place, so as to give a gentle
curve; all these touches gradually shape the figure
and mould it out of the rough stone, first into a rude
shape and afterward, by delicate strokes, into the form
of a living being.

Now, just in the same way as the wrinkles and
curves of a statue are cut by the sculptor's chisel, so
the hills and valleys, the steep slopes and gentle curves
on the face of our earth, giving it all its beauty, and
the varied landscapes we love so well, have been cut
out by water and ice passing over them. It is true
that some of the greater wrinkles of the earth, the
lofty mountains, and the high masses of land which
rise above the sea, have been caused by earthquakes

THE TWO GREAT SCULPTORS. 105

and shrinking of the earth. We shall not speak of
these to-day, but put them aside as belonging to the
rough work of the statuary yard. But when once
these large masses are put ready for water to work
upon, then all the rest of the rugged wrinkles and
gentle slopes which make the country so beautiful are
due to water and ice ; and for this reason I have called
them " sculptors."

Go for a walk in the country, or notice the land-
scape as you travel on a railway journey. You pass
by hills and through valleys, through narrow steep
gorges cut in hard rock, or through wild ravines up
the sides of which you can hardly scramble. Then
you come to grassy slopes and to smooth plains across
which you can look for miles without seeing a hill ;
or, when you arrive at the seashore, you clamber into
caves and grottos, and along dark narrow passages
leading from one bay to another. All these — hills,
valleys, gorges, ravines, slopes, plains, caves, grottos,
and rocky shores — have been cut out by water. Day
by day and year by year, while everything seems to
us to remain the same, this industrious sculptor is
chipping away, a few grains here, a corner there, a
large mass in another place, till he gives to the coun-
try its own peculiar scenery, just as the human sculp-
tor gives expression to his statue.

Our work to-day will consist in trying to form some
idea of the way in which water thus carves out the
surface of the earth, and we will begin by seeing how
much can be done by our old friends the rain-drops
before they become nmning streams.

Evcrvone must have noticed that whenever rain

^f 106 THR FAIRY-LAND OF SCIENCE. ^H

H falls on soft ground it makes small round holes in H

^B which it collects and then sniks mto the ground, ^H

^H forcing its way between the grams of earth. But ^H

H^ vou would hardly ^|

j__ __

1 »

beautiful pillars

m Fig. 26 have

been made entire-
ly in this way
by rain beating

",' ^ J '1

upon and soaking

it '

mto the ground.

Rather would you

ii|>pose theywere

Iiiiilt by people

^ tiV'^ ' ^

v\lio lived in very

1 1 ^

early times in the

country in which

■ r '.* t « 1 .

they are found,

I »' « J^f 1

as were the

■ B 1 irl.„ .i-

rude structures at

■ pluiw l:HlHi

Stonehenge, in

1 LiMnv^^'^fll

England, erected

^L HMlBiHiMwJP'jjtjiiW'^^l before the ancient ^H

^^m j^^^jPWPj^g'lK^^irfJt^lHiMBI Britons were any- ^H

■ Fl« .5-Eathp a n..r HoU.n n t''i»g l^^"^*- '''^" 1

^V the Tyrol, forly feet h.gh. savageS, Or the ^H

^B Strange edifices ^H

^p made in a similar manner of rough stones by the ^H

^ Peruvian Indians in South America before the white ^|

man came into this part of the world. ^|

THE TWO GREAT SCULPTORS.

107

You may see these pillars if you visit Botzen, in
the Austrian Tyrol, amid the Rosengarten Mountains.
In order to reach this place you must go by rail from
Innsbruck, through the Brenner Pass, over a road

Fig. a6.— Earth
til at [esembli

that runs through no less than

twenty-seven tunnels, over a great

many bridges, and a series of

grades one above the other, so that you can look from

a window in your car down upon the roofs of trains

of cars ahead several hundred feet below.

The largest of the pillars here shown is no less than
forty feet high, and the other one not much less. The
next picture shows a group of these pillars that look
like a church with a number of spires or pinnacles.
Where they now stand there was once a solid mass
of clay and stones, into which the rain-drops crept,
loosening the earthy particles; and then when the

THE TWO GREAT SCULPTORS.

109

sun dried the earth again cracks were formed, so
that the next shower loosened it still more, and carried
some of the mud down into the valley below. But
here and there large stones were buried in the clay,
and where this happened the rain could not penetrate,
and the stones became the tops of tall pillars of clay,
washed into shape by the rain beating on its sides, but
escaping the general destruction of the rest of the
mud. In this way the whole valley has been carved
out into fine pillars, some still having capping-stones,
w^hile others have lost them, and these last will soon
be washed away. You may sometimes see tiny pillars
under bridges or the hollows worn by the continual
dripping of the rain from the eaves of a house, where
the water has washed away the earth between the peb-
bles, and such small examples which you can observe
for yourselves are quite as instructive as more impor-
tant ones.

We have much finer and larger earth pillars in
our own country. A celebrated geologist, Mr. Prest-
wich, says in speaking of some that he saw in Wyo-
ming : " For about three miles along the side of South
River and for half a mile in width the wooded slopes
are studded by hundreds of these monuments, some
of which rise to the height of four hundred feet, the
average being from sixty to eighty feet. High spruce
trees of great size seem like dwarfs by the side of
these mighty columns, each one of which is capped by
a boulder." The soil beneath these great earth pillars
is of a soft and crumbling character.

Another way in which rain changes the surface of
the earth is by sinking down through loose soil from

no THE FAIRY^LAND OF SCIENCE.

the top of a cliff to a depth of many feet till it comes to
solid rock, and then lying spread over a wide space.
Here it forms a kind of watery mud, which is a very
unsafe foundation for the hill of earth above it, and so
after a time the whole mass slips down and makes a
fresh piece of land at the foot of the cliff. If you have
ever been at the Isle of Wight you will have seen an
undulating strip of ground, called the Undercliff, at
V^tnor and other places, stretching all along the sea
below the high cliffs. This land was once at the top
of the cliff, and came down by a succession of land-
slips such as we have been describing.

You will easily see how in forming earth-pillars
and causing landslips rain changes the face of the
country, but these are only rare effects of water. It is
when the rain collects in brooks and forms rivers that
it is most busy in sculpturing the land. Look out
some day into the road or the garden where the ground
slopes a little, and watch what happens during a
shower of rain. First the rain-drops nm together in
every little hollow of the ground, then the water be-
gins to flow along any ruts or channels it can find,
lying here and there in pools, but always making its
way gradually down the slope. Meanwhile from other
parts of the ground little rills are coming, and these
all meet in some larger ruts where the ground is low-
est, making one great stream, which at last empties
itself into the gutter or an area, or finds its way dovv^n
some gratings into the sewer.

Now just this, which we can watch whenever a
heavy shower of rain comes down on the road, hap-

THE TWO GREAT SCULPTORS. m

pens also all over the world. Up in the mountains,
where there is always a great deal of rain, little rills
gather and fall over the mountain sides, meeting in
some stream below. Then, as this stream flows on, it
is fed by many runnels of water, which come from all
parts of the country, trickling along ruts, and flowing
in small brooks and rivulets down the gentle slope of
the land till they reach the big stream, which at last
is important enough to be called a river. Sometimes
this river comes to a large hollow in the land and there
the water gathers and forms a lake; but still at the
lower end of this lake out it comes again, forming a
new river, and growing and growing by receiving fresh
streams until at last it reaches the sea.

The River Thames, which you all know, and whose
course you will find clearly described in Mr. Huxley's
" Physiography,'' drains in this way no less than one-
seventh of the whole of England. All the rain which
falls in Berkshire, Oxfordshire, Middlesex, Hertford-
shire, Surrey, the north of Wiltshire and northwest of
Kent, the south of Buckinghamshire and of Glouces-
tershire, finds its way into the Thames; making an
area of 6160 square miles over which the water of every
little rivulet and brook finds its way down to the one
great river, which bears them to the ocean. And so
with every other area of land in the world there is some
one channel toward which the ground on all sides
slopes gently down, and into this channel all the water
will run, on its way to the sea.

But what has this to do with sculpture or cutting
out of valleys? If you will only take a glass of water
out of any river, and let it stand for some hours, you

112 THE FAIRY-LAND OF SCIENCE.

will soon answer this question for yourself. For you
will find that even from river water which looks quite
clear, a thin layer of mud will fall to the bottom of
the glass, and if you take the water when the river is
swollen and muddy you will get quite a thick deposit.
This shows that the brooks, the streams, and the rivers
wash away the land as they flow over it and carry it
from the mountains down to the valleys, and from the
valleys away out into the sea.

But besides earthy matter, which we can see, there
is much matter dissolved in the water of rivers (as we
mentioned in the last lecture), and this we can not see.

If you use water which comes out of a chalk coun-
try you will find that after a time the kettle in which
you have been in the habit of boiling this water has
a hard crust on its bottom and sides, and this crust
is made of chalk or carbonate of lime, which the water
took out of the rocks when it was passing through
them. Professor Bischoff has calculated that the river
Rhine carries past Bonn every year enough carbonate
of lime dissolved in its water to make 332,000 million
oyster-shells, and that if all these shells were built into
a cube it would measure 560 feet.

Imagine to yourself a building, perhaps larger than
any you have ever seen — as large, for example, as the
State, War, and Navy Department buildings at Wash-
ington — an edifice that extends over a space measur-
ing five hundred and sixty-seven feet in one direction
and four hundred and seventy-one in the other, com-
pletely filled up, covered over, and deeply buried in
a great square mound of oyster shells extending many
times the height of the building above it; then you

THE TWO GREAT SCULPTORS, 113

will have some idea of the amount of chalk carried
invisibly past Bonn in the water of the Rhine every
year.

Since all this matter, whether brought down as
mud or dissolved, comes from one part of the land
to be carried elsewhere or out to sea, it is clear that
some gaps and hollows must be left in the places from
which it is taken. Let us see how these gaps are
made. Have you ever clambered up the mountain-
side, or even up one of those small ravines in the hill-
side, which have generally a little stream trickling
through them? If so, you must have noticed the
number of pebbles, large and small, lying in patches
here and there in the stream, and many pieces of
broken rock, which are often scattered along the sides
of the ravine; and how, as you climb, the path grows
steeper, and the rocks become rugged and stick out
in strange shapes.

The history of this ravine will tell us a great deal
about the carving of water. Once it was nothing
more than a little furrow in the hill-side down which
the rain found its way in a thin thread-like stream.
But by and by, as the stream carried down some of
the earth, and the furrow grew deeper and wider, the
sides began to crumble when the sun dried up the
rain which had soaked in. Then in winter, when the
sides of the hill were moist with the autumn rains,
frost came and turned the water to ice, and so made
the cracks still larger, and the swollen stream rushing
down, rauflfhiL-ilMt lx)se pieces of rock and washed
ther Here they were rolled over

an* 'list each other, and were

114

THE FAIRY-LAND OF SCIENCE.

ground away till they became rounded pebbles, such
as lie in the foreground of the picture (Fig. 28) ; while
the grit which was rubbed off them was carried far-
ther down by the stream. And so in time this be-

came a little valley, and as the stream cut it deeper
and deeper, there was room to clamber along the
sides of it, and ferns and mosses began to cover the
naked stone, and small trees rooted themselves along
the banks, and this beautiful little nook sprang up on
the hill-side entirely by the sculpturing of water.

THE TWO GREAT SCULPTORS. uj

Shall you not feel a fresh interest in all the little
valleys, ravines, and gorges you meet with in the
country, if you can picture them being formed in this
way year by year? There are many curious differ-
ences in them which you can study for yourselves.
Some will be smooth, broad valleys, and here the rocks
have been soft and easily worn, and water trickling
down the sides of the first valley has cut other chan-
nels so as to make smaller valleys running across it.
In other places there will be narrow ravines, and here
the rocks have been hard, so that they did not wear
away gradually, but broke off and fell in blocks, leav-
ing high cliffs on each side. In some places you will
come to a beautiful waterfall, where the water has tum-
bled over a steep cliff, and then eaten its way back,
just like a saw cutting through a piece of wood.

There are two things in particular to notice in a
waterfall like this. First, how the water and spray
dash against the bottom of the cliff down which it
falls, and grind the small pebbles against the rock.
In this way the bottom of the cliff is undermined, and
so great pieces tumble down from time to time, and
keep the fall upright instead of its being sloped away
at the top, and becoming a mere stream. Secondly,
you may often see curious cup-shaped holes, called
" pot-holes," in the rocks on the sides of a waterfall,
and these also are concerned in its formation. In
these holes you will generally find two or three small
pebbles, and you have here a beautiful example of
how water uses stones to grind away the face of the
earth. These holes are made entirely by the falling
water eddying round and round in a small hollow of

'^^^•■''- LIJf.AKY

THE TWO GREAT SCULPTORS.

117

could not see him without a telescope ; while the open-
ing at the top between the two walls would seem so
narrow at such an immense distance that the sky
above would have the appearance of nothing more
than a narrow Streak of blue. Yet these huge chasms
have not been made by any violent breaking apart
of the rocks or convulsion of an earthquake. No,
they have been gradually, silently, and steadily cut
through by the river which now glides quietly in the
wider chasms, or rushes rapidly through the narrow
gorges at their feet.

" No description," says Lieutenant Ives, one of the
first explorers of this river, " can convey the idea of
the varied and majestic grandeur of this peerless water-
way. Wherever the river turns, the entire panorama
changes. Stately faqades, august cathedrals, amphi-
theatres, rotundas, castellated walls, and rows of time-
stained ruins, surmounted by every form of tower,
minaret, dome and spire, have been moulded from the
Cyclopean masses of rock that form the mighty de-
file." Who will say, after this, that water is not the
grandest of all sculptors, as it cuts through hundreds
of miles of rock, forming such magnificent granite
groups, not only unsurpassed but unequalled by any
of the works of man?

But we must not look upon water only as a cutting
instrument, for it does more than merely carve out
land in one place, it also carries it away and lays it
down elsewhere ; and in this it is most like a modeller
in clay, who smooths off the material from one part of
his figure to put it upon another.

Il8 THE FAIRY-LAND OF SCIENCE.

Running water is not only always carrying away
mud, but at the same time laying it down here and
there wherever it flows. When a torrent brings down
stones and gravel from the mountains, it will depend
on the size and weight of the pieces how long they
will be in falling through the water. If you take a
handful of gravel and throw it into a glass full of
water, you will notice that the stones in it will fall to
the bottom at once, the grit and coarse sand will take
longer in sinking, and lastly, the fine sand will be
an hour or two in settling down, so that the water
becomes clear. Now, suppose that this gravel were
sinking in the water of a river. The stones would be
buoyed up as long as the river was very full and
flowed very quickly, but they would drop through
sooner than the coarse sand. The coarse sand in its
turn would begin to sink as the river flowed more
slowly, and would reach the bottom while the fine
sand was still borne on. Lastly, the fine sand would
sink through very, very slowly, and only settle in com-
paratively still water.

From this it will happen that stones will generally
lie near to the bottom of torrents at the foot of the
banks from which they fall, while the gravel will be
carried on by the stream after it leaves the mountains.
This too, however, will be laid down when the river
comes into a more level country and nms more slowly.
Or it may be left together with the finer mud in a lake,
as in the lake of Geneva, into which the Rhone flows
laden with mud and comes out at the other end clear
and pure. But if no lake lies in the way the finer
earth will still travel on, and the river will take up

THE TWO GREAT SCULPTORS.

119

more and more as it flows, till at last it will leave this
too on the plains across which it moves sluggishly
along, or will deposit it at its mouth when it joins
the sea.

You all know the history of the Nile; how, when
the rains fall very heavily in March and April in the
mountains of Abyssinia, the river comes rushing down,
and brings with it a load of mud which it spreads out
over the Nile valley in Egypt. This annual layer of
mud is so thin that it takes a thousand years for it
to become 2 or 3 feet thick; but besides that which
falls in the valley a great deal is taken to the mouth
of the river and there forms new land, making what is
called the " Delta " of the Nile. Alexandria, Rosetta,
and Damietta, are towns which are all built on land
made of Nile mud which was carried down ages and
ages ago, and which has now become firm and hard
like the rest of the country. You will easily remember
other deltas mentioned in books, and all these are
made of the mud carried down from the land to the
sea. The delta of the Ganges and Brahmapootra in
India, is actually as large as the whole of England and
Wales,* and the' River Mississippi in America drains
such a large tract of country that its delta grows, Sir
A. Geikie tells us, at the rate of 86 yards in a year.

All this new land laid down in Egypt, in India, in
America, and in other places, is the work of water.
Even on the Thames you may see mud-banks, as at
Gravesend, which are made of earth brought from
the interior of England. But at the mouth of the
Thames the sea washes up very strongly every tide,

* 58,311 square miles.

I20 THE FAIRY-LAND OF SCIENCE.

and so it carries most of the mud away and prevents
a delta growing up there. If you will look about when
vou are at the seaside, and notice wherever a stream
flows down into the sea, you may even see little min-
iature deltas being formed there, though the sea gen-
erally washes them away again in a few hours, tmless
the place is well sheltered.

This, then, is what becomes of the earth carried
down by rivers. Either on plains, or in lakes, or in
the sea, it falls down to form new land. But what
becomes of the dissolved chalk and other substances?
\\'e have seen that a great deal of it is used by river
and sea animals to build their shells and skeletons,
and some of it is left on the surface of the ground by
springs when the water evaporates. It is this car-
bonate of lime which forms a hard crust over anv-
thing upon which it may happen to be deposited, and
then these things are called " petrified."

But it is in the caves and hollows of the earth
that this dissolved matter is built up into the most
beautiful forms. If vou have ever been to Buxton in
Derbyshire, you will probably have visited a cavern
called Poole's Cavern, not far from there, which when
you enter it looks as if it were built up entirely of
rods of beautiful transparent white glass, hanging from
the ceiling, from the walls, or rising up from the floor.
In this cavern, and many others like it,* water comes
(lrip])ing through the roof, and as it falls slowly drop
by drop it leaves behind a little of the carbonate of
lime it has brought out of the rocks. This carbonate
of lime forms itself into a thin, white film on the roof,

♦ See the picture at the head of the lecture.

THE TWO GREAT SCULPTORS, \2\

often making a complete circle, and then, as the water
drips from it day by day, it goes on growing and grow-
ing till it forms a long needle-shaped or tube-shaped
rod, hanging like an icicle. These rods are called
stalactites, and they are so beautiful, as their minute
crystals glisten when a light is taken into the cavern,
that one of them near Tenby is called the " Fairy
Chamber." Meanwhile, the water which drips on to
the floor also leaves some carbonate of lime where it
falls, and this forms a pillar, growing up toward the
roof, and often the hanging stalactites and the rising
pillars (called stalagmites) meet in the middle and form
one column. And thus we see that underground, as
well as aboveground, water moulds beautiful forms in
the crust of the earth. At Adelsberg, near Trieste,
there is a magnificent stalactite grotto made of a num-
ber of chambers one following another, with a river
flowing through them; and the famous Mammoth
Cave of Kentucky, more than ten miles long, is an-
other example of these wonderful limestone caverns.

But we have not yet spoken of the sea, and this
surely is not idle in altering the shape of the land.
Even the waves themselves in a storm wash against
the cliflFs and bring down stones and pieces of rock on
to the shore below. And they help to make cracks
and holes in the cliffs, for as they dash with force
against them they compress the air which lies in the
joints of the stone and cause it to force the rock apart,
and so larger cracks are made and the cliff is ready
to crumble.

It is, however, the stones and sand and pieces of

122 THE FAIRY-LAXD OF SCIEXCE,

rock lying at the foot of the cliff which are most active
in wearing it awav. Have you never watched the
waves breaking upon a beach in a heavy storm? How
they catch up the stones and hurl them do^i^-n again,
grinding them against each other! At high tide in
such a storm these stones are thrown against the foot
of the cliff, and each blow does something toward
knocking away part of the rock, till at last, after many
storms, the cliff is undermined and large pieces fall
down. These pieces are in their turn ground doii-n
to pebbles which ser\'e to batter against the remain-
ing rock.

Professor Geikie tells us that the waves beat in
a storm against the Bell Rock Lighthouse with as
much force as if you dashed a weight of 3 tons against
ever}' square inch of the rock, and Stevenson found
stones of 2 tons* weight which had been thrown dur-
ing storms right over the ledge of the lighthouse.
Think what force there must be in waves which
can lift up such a rock and throw it, and such force
as this beats upon our sea-coasts and eats away the
land.

Fig. 30 is a sketch on the shores of Arbroath which
I made some years ago. You will not find it diffi-
cult to picture to yourselves how the sea has eaten
away these cliffs till some of the strongest pieces which
have resisted the waves stand out bv themselves in
the sea. That cave in the left-hand comer ends in a
narrow dark passage from which you come out on
the other side of the rocks into another bav. Such
caves as these are made chiefly by the force of the
waves and the air, bringing down pieces of rock from

THE TWO GREAT SCULPTORS. 123 ^H

under the cliff and so making a cavity, and then as H

the waves roll these pieces over and over and grind
them against the sides, the hole is made larger. There
are many places on the English coast where large
pieces of the road are destroyed by the crumbling

Fig. 30. — Cliffs off Arbroath, stiowing

dovm of cliffs when they have been undermined by
caverns such as these.

Thus, you see, the whole of the beautifid scenery of
the sea — -the shores, the steep cliffs, the quiet bays, the
creeks and caverns — are all the work of the " sculptor "
water ; and he works best where the rocks are hardest,
for there they offer him a good stotit wall to batter,
whereas in places where the ground is soft it washes
down into a gradual gentle slope, and so the waves

124 ^^^ FAIRY-LAND OF SCIENCE,

come flowing smoothly in and have no power to eat
away the shore.

And now, what has Ice got to do with the sculp-
turing of the land? First, we must remember how
much the frost does in breaking up the ground. The
farmers know this, and always plough after a frost, be-
cause the moisture, freezing in the ground, has broken
up the clods, and done half their work for them.

But this is not the chief work of ice. You will
remember how we learned in our last lecture that
snow, when it falls on the mountains, gradually slides
down into the valleys, and is pressed together by the
gathering snow behind until it becomes moulded into
a solid river of ice (see Fig. 31, Frontispiece). In
Greenland and in Norway there are enormous ice-
rivers or glaciers, and even in Switzerland some of
them are very large. The Aletsch glacier, in the Alps,
is fifteen miles long, and some are even longer than
this. They move very slowly — on an average about
20 to 2y inches in the centre, and 13 to 19 inches at
the sides every twenty-four hours, in summer and au-
tumn. How they move, we cannot stop to discuss
now; but if you will take a slab of thin ice and rest
it upon its two ends only, you can prove to yourself
that ice does bend, for in a few hours you will find
that its own weight has drawn it down in the centre
so as to form a curve. This will help you to picture
to yourself how glaciers can adapt themselves to the
windings of the valley, creeping slowly onward until
they come down to a point where the air is warm
enough to melt them, and then the ice flows away in

THE TWO GREAT SCULPTORS.

125

a stream of water. It is very curious to see the num-
ber of little rills running down the great masses of
ice at the glacier's mouth, bringing down with them
gravel, and every now and then a large stone, which
falls splashing into the stream below. If you look at
the glacier in the Frontispiece, you will see that these
stones come from those long lines of stones and boul-
ders stretching along the sides and centre of the gla-
cier. It is easy to understand where the stones at the
side come from; for we have seen that damp and
frost cause pieces to break off the surface of the rocks,
and it is natural that these pieces should roll down
the steep sides of the mountains on to the glacier.
But the middle row requires some explanation. Look
to the back of the picture, and you will see that this
line of stones is made of two side rows, which come
from the valleys above. Two glaciers, you see, have
there joined into one, and so made a heap of stones all
along their line of junction.

These stones are being continually, though slowly,
conveyed by the glacier, from all the mountains along
its sides, down to the place where it melts. Here it
lets them fall, and they are gradually piled up till they
form great walls of stone, which are called moraines.
Some of the moraines left by the larger glaciers of
olden time, in the country near Turin, form high hills,
rising up even to 1500 feet.

Therefore, if ice did no more than carry these
stone blocks, it would alter the face of the country;
but it does much more than this. As the glacier moves
along, it often cracks for a considerable way across
its surface, and this crack widens and widens, until at

126 THE FAIRY-LAND OF SCIENCE,

last it becomes a great gaping chasm, or crevasse as
it is called, so that you can look down it right to the
bottom of the glacier. Into these crevasses large
blocks of rock fall, and when the chasm is closed
again as the ice presses on, these masses are frozen
firmly into the bottom of the glacier, much in the
same way as a steel cutter is fixed in the bottom of a
plane. And they do just the same kind of work; for
as the glacier slides down the valley, they scratch and
grind the rocks underneath them, rubbing themselves
away, it is true, but also scraping away the ground
over w^hich they move. In this way the glacier be-
comes a cutting instrument, and carves out the valleys
deeper and deeper as it passes through them.

You may always know where a glacier has been,
even if no trace of ice remains ; for you will see rocks
with scratches along them which have been cut by
these stones ; and even where the rocks have not been
ground away, you will find them rounded like those in
the left-hand of the Frontispiece, showing that the
glacier-plane has been over them. These rounded
rocks are called " roches moutonnees," because at the
distance they look like sheep lying down.

You have only to look at the stream flowing from
the mouth of a glacier to see what a quantity of soil
it has ground oflF from the bottom of the valley; for
the water is thick, and coloured a deep yellow by the
mud it carries. This mud soon reaches the rivers into
which the streams run; and such rivers as the Rhone
and the Rhine are thick with matter brought down
from the Alps. The Rhone leaves this mud in *'
Lake of Geneva, flowing out at the other end

THE TWO GREAT SCULPTORS. 127

clear and pure. A mile and a half of land has been
formed at the head of the lake since the time of the
Romans by the mud thus brought down from the
mountains.

Thus we see that ice, like water, is always busy
carving out the surface of the earth, and sending down
material to make new land elsewhere. We know that
in past ages the glaciers were much larger than they
are in our time ; for we find traces of them over large
parts of Switzerland where glaciers do not now exist,
and huge blocks which could only have been carried
by ice, and which are called '' erratic blocks," some of
them as big as cottages, have been left scattered over
all the northern part of Europe. These blocks were
a great puzzle to scientific men till, in 1840, Professor
Agassiz showed that they must have been brought by
ice all the way from Norway and Russia.

In those ancient days, there were even glaciers in
England; for in Cumberland and in Wales you may
see their work, in scratched and rounded rocks, and
the moraines they have left. Llanberis Pass, so fa-
mous for its beauty, is covered with ice-scratches, and
blocks are scattered all over the sides of the valley.
There is one block high up on the right-hand slope
of the valley, as you enter from the Beddgelert side,
which is exactly poised upon another block, so that
it rocks to and fro. It must have been left thus bal-
anced when the ice melted round it. You may easily
see that these blocks were carried by ice, and not

their edges are sharp, whereas, if
water, they would have been

128 THE FAIRY-LAND OF SCIENCE,

We cannot here go into the history of that great
Glacial Period long ago, when large fields of ice cov-
ered all the north of England; but when you read
it for yourselves and understand the changes on the
earth's surface which we can see being made by ice
now» then such grand scenery as the rugged valleys
of Wales, with large angular stone blocks scattered
over them, will tell you a wonderful story of the ice
of bygone times.

And now we have touched lightly on the chief
ways in which water and ice carve out the surface
of the earth. We have seen that rain, rivers, springs,
the waves of the sea, frost, and glaciers all do their
part in chiselling out ravines and valleys, and in pro-
ducing nigged peaks or undulating plains — here cut-
ting through rocks so as to form precipitous cliffs,
tliere layitig down new land to add to the flat country
in t>ne place grinding stones to powder, in others
piling them up in gigantic ridges. We cannot go a
sh'p into the country without seeing the work of water
mumhhI us; every little gully and ravine tells us that
tlir srulptmv is going on; every stream, with its bur-
\\v\\ of visible or invisible matter, reminds us that
M)me earth is being taken away and carried to a new
spot, In our little lives we see indeed but very small
rhanges, but by these we learn how greater ones have
bren bn night abintt, and how we owe the outline of
all t>m' beautiful scenerv, with its hills and vallevs,
its nunmtains and plains, its cHfTs and caverns, its
tjuiti ni)oks and its grand nigged precipices, to the
work of the *' Two great sculptors. Water and Ice."

THE VOICES OF NA TURE.

LECTURE VI.

iKiw WK iii;ak the:

J^URlTE l]a\e readied \

3 Vf^ to da> the i

die point of our course, an<i here we will make a new
start. All the wonderful histories which we have been
studying in the last five lectures have had little or
nothing to do with living creatures. The sunbeams

I30

THE FAIRY-LAND OF SCIENCE,

would strike on our earth, the air would move rest-
lessly to and fro, the water drops would rise and fall,
the valleys and ravines would still be cut out by
rivers, if there were no such thing as life upon the
earth. But without living things there could be none
of the beauty which these changes bring about.
Without plants, the sunbeams, the air, and the water
would be quite unable to clothe the bare rocks, and
without animals and man they could not produce
light, or sound, or feeling of any kind.

In the next five lectures, however, we are going to
learn something of the use living creatures make of
the earth; and to-day we will begin by studying one
of the ways in which we are aflFected by the changes
of nature, and hear her voice.

We are all so accustomed to trust to our sight to
guide us in most of our actions, and to think of things
as we see them, that we often forget how very much
we owe to sound. And yet nature speaks to us so
much by her gentle, her touching, or her awful sounds,
that the life of the deaf person is even more hard to
bear than that of a blind one.

Have you ever amused yourself with trying how
many different sounds you can distinguish if you lis-
ten at an open window in a busy street? You will
probably be able to recognise easily the jolting of the
heavy wagon or dray, the humming of the trolley cars,
the smooth roll of the private carriage, and the rattle
of the light butcher's cart ; and even while you are lis-
tening for these, the crack of the carter's whip, the cry
of the passing vender, and the voices of the passers
by will strike upon your ear. Then if you give still

THE VOICES OF NA TURE.

131

more close attention you will hear the doors open and
shut along the street, the footsteps of the passengers,
and the scraping of the shovel of the mud-carts. If
you think for a moment, does it not seem wonderful
that you should hear all these sounds so that you can
recognise each one distinctly while all the rest are
going on around you?

But suppose you go into the quiet country. Sure-
ly there will be silence there. Try some day and prove
it for yourself, lie down on the grass in a sheltered
nook and listen attentively. If there be ever so little
wind stirring you will hear it rustling gently through
the trees ; or even if there is not this, it will be strange
if you do not hear some wandering gnat buzzing, or
some busy bee humming as it moves from flower to
flower. Then a grasshopper or katydid will set up
a chirp within a few yards of you, or, if all living crea-
tures are silent, a brook not far off may be flowing
along with a rippling musical sound. These and a
hundred other noises you will hear in the most quiet
country spot; the lowing of cattle, the song of the
birds, the squeak of the field-mouse, the croak of the
frog, mingling with the sound of the woodman's axe
in the distance, or the dash of some river torrent.
And besides these quiet sounds, there are still other
occasional voices of nature which speak to us from
time to time. The howling of the tempestuous wind,
the roar of the sea-waves in a storm, the crash of thun-
der, and the mighty noise of the falling avalanche;
such sounds as these tell us how great and terrible na-
ture can be.

Now, has it ever occurred to you to think what
10

132 THE FAIRY'LAXD OF SCIENCE.

sound is, and how it is that we hear all these thingfs?
Strange as it may seem, if there were no creature that
could hear upon the earth, there would be no such
thing as sound, though all these movements in nature
were going on just as they are now.

Try and g^sp this thoroughly, for it is difficult at
first to make people believe it. Suppose you were
stone-deaf, there would be no such thing as sound to
you. A heavy hammer falling on an anvil would in-
deed shake the air violently, but since this air when
it reached vour ear would find a useless instrument,
it could not play upon it. And it is this play on the
drum of your car and the nenrs unthin it speaking to
your brain li'hich makes sound. Therefore, if all crea-
tures on or around the earth were without ears or
nerves of hearing, there would be no instruments on
which to play, and consequently there would be no
such thing as sound. This proves that two things
are needed in order that we may hear. First, the
outside movement which plays on our hearing instru-
ment; and, secondly, the hearing instrument itself.

First, then, let us try to understand what happens
outside our ears. Take a poker and tie a piece of
string to it, and holding the ends of the string to your
ears, strike the poker against the fender. You will
hear a very loud sound, for the blow will set all the
particles of the poker quivering, and this movement
will pass right along the string to the drum of your
ear and play upon it.

Now take the string away from your ears, and hold
it with your teeth. Stop your ears tight, and strike

THE VOICES OF NATURE.

133

the poker once more against the fender. You will
hear the sound quite as loudly and clearly as you did
before, but this time the drum of your ear has not
been agitated. How, then, has the sound been pro-
duced? In this case, the quivering movement has
passed through your teeth into the bones of your head,
and from them into the nerves, and so produced sound
in your brain. And now, as a final experiment, fasten
the string to the mantelpiece, and hit it again against
the fender. How much feebler the sound is this time,
and how much sooner it stops! Yet still it reaches
you, for the movement has come this time across the
air to the drum of your ear.

Here we are back again in the land of invisible
workers! We have all been listening and hearing
ever since we were babies, but have we ever made any
picture to ourselves of how sound comes to us right
across a room or a field, when we stand at one end
and the person who calls is at the other?

Since we have studied the " aerial ocean," we know
that the air filling the space between us, though in-
visible, is something very real, and now all we have to
do is to understand exactly how the movement crosses
this air.

This we shall do most readily by means of an
experiment made by Dr. Tyndall in his lectures on
Sound. I have here a number of boxwood balls rest-
ing in a wooden tray which has a bell hung at the
end of it. I am going to take the end ball and roll
it sharply against the rest, and then I want you to
notice carefully what happens. See! the ball at the
other end has flown oflF and hit the bell, so that you

»34

TVE FA/ar-LAMD OF SCIEfTCE.

bear it ring. Yet the other balls remain where they-
were before. Why is this? It is because each of the
balls, as it was knocked forward, had one in front of
it to stop it and make it bound back again, but the
last one was free to move on. When I threw this ball
from my hand against the others, the one in front of
it moved, and hitting tbe third ball, bounded back
again; the third did the same to the fourth, the founh

Fig. 33.

to the fifth, and so on to the end of the line. Each
ball thus came back to its place, but it passed the
shock on to the last batl. and the ball to the bell. If I
now put the balls close up to the bell, and repeat the
experiment, you still hear the sound, for the last ball
shakes the bell as if it were a ball in front of it.

Now imagine these balls to be atoms of air, and the
bell your ear. If I clap my hands and so hit the air
in front of them, each air-atom hits the next just as
the balls did, and though it comes back to its place,
it passes the shock on along the whole line to the
atom touching the drum of your ear, and so you re-
ceive a blow. But a curious thing happens in the
air which you cannot notice in the balls. You must
remember that air is elastic, just as if there were
sjiring.s between the atoms as in the diagram, Fig. 33,
and so when any shock knocks the atoms forward,

THE VOICES OF JVA TURE.

135

several of them can be crowded together before they
push on those in front. Then, as soon as they have
p^sed the shock on, they rebound and begin to sepa-
rate again, and so swing to and fro till they come
to rest. Meanwhile the second set will go through
just the same movements, and wiU spring apart as soon
as they have passed the shock on to a third set, and so
you will have one set of crowded atoms and one set

of separated atoms alternately all along the line, and
the same set will never be crowded two instants to-
gether.

You may see an excellent example of this in a
baggage train in a railway station, when the trucks are
left to bump each other till they stop. You will see
three or four trucks knock together, then they will
pass the shock on to the four in front, while they
themselves bound back and separate as far as their
chains will let them: the next four trucks will do the
same, and so a kind of wave of crowded trucks passes
on to the end of the train, and they bump to and fro
till the whole comes to a standstill. Try to imagine
a movement like this going on in the line of air-atoms,
Fig. 33, the drum of your ear being at the end E.
Those which are crowded together at that end will
hit on the drum of your ear and drive the membrane
which covers it inward; then instantly the wave will

136

THE FAIRY-LAND OF SCIENCE.

change, these atoms will bound back, and the mem-
brane will recover itself again, but only to receive a
second blow as the atoms are driven forward again,
and so the membrane will be driven in and out till the
air has settled down.

This you see is quite different to the waves of light
which moves in crests and hollows. Indeed, it is not
what we usually understand by a wave at all, but a
set of crowdings and partings of the atoms of air
which follow each other rapidly across the air. A
crowding of atoms is called a condensation, and a part-
ing is called a rarefaction, and when we speak of the
length of a wave of sound, we mean the distance be-

Fig. 34.

tween two condensations, a a, Fig. 34, or between
two rarefactions, b b.

Although each atom of air moves a very little way
forward and then back, yet, as a long row of atoms
may be crowded together before they begin to part, a
wave is often very long. When a man talks in an
ordinary bass voice, he makes sound-waves from 8 to
12 feet long; a woman's voice makes shorter waves,
from 2 to 4 feet long, and consequently the tone is
higher, as we shall presently explain.

And now I hope that some one is anxious to ask
why, when I clap my hands, anyone behind me or at
the side, can hear it as well or nearly as well as you

THE VOICES OF NATURE, 137

who are in front. This is because I give a shock to
the air all round my hands, and waves go out on all
sides, making as it were globes of crowdings and
partings, widening and widening away from the clap
as circles widen on a pond. Thus the waves travel
behind me, above me, and on all sides, until they hit
the walls, the ceiling, and the floor of the room, and
wherever you happen to be, they hit upon your ear.

If you can picture to yourself these waves spread-
ing out in all directions, you will easily see why sound
grows fainter at the distance. Just close round my
hands when I clap them, there is a small quantity of
air, and so the shock I give it is very violent, but
as the sound-waves spread on all sides they have
more and more air to move, and so the air-atoms are
shaken less violently and strike with less force on
your ear.

If we can prevent the sound-wave from spreading,
then the sound is not weakened. The Frenchman Biot
found that a low whisper could be heard distinctly for
a distance of half a mile through a tube, because the
waves could not spread beyond the small column of
air. But unless you speak into a small space of some
kind, you can not prevent the waves going out from
you in all directions.

Try and imagine that you see these waves spread-
ing all round me now and hitting on your ears as they
pass, then on the ears of those behind you, and on
and on in widening globes till they reach the wall.
What will happen when they get there? If the wall
were thin, as a wooden partition is, they would shake
it, and it again would shake the air on the other side,

138 THE FAIRY-LAND OF SCIENCE,

and so persons in the next room would have the sound
of my voice brought to their ear.

But something more will happen. In any case
the sound-waves hitting against the wall will bound
back from it just as a ball bounds back when thrown
against anything, and so another set of sound-waves
reflected from the wall will come back across the
room. If these waves come to your ear so quickly
that they mix with direct waves, they help to make the
sound louder. For instance, if I say " Ha," you hear
that sound louder in this room than you would in the
open air, for the " Ha " from my mouth and a second
" Ha " from the wall come to your ear so instantane-
ously that they make one sound. This is why you
can often hear better at the far end of a church when
you stand against a screen or a wall, that when you
are halfway up the building nearer to the speaker,
because near the wall the reflected waves strike strong-
ly on your ear and make the sound louder.

Sometimes, when the sound comes from a great
explosion, these reflected waves are so strong that they
are able to break glass. In the explosion of gun-
powder in St. John's Wood, many houses in the back
streets had their windows broken ; for the sound-waves
bounded off at angles from the walls and struck back
upon them.

Now, suppose the wall were so far behind you that
the reflected sound-waves only hit upon your ear after
those coming straight from me had died away; then
vou would hear the sound twice, " Ha " from me and
Ha " from the wall, and here you have an echo.
Ha, ha." In order for this to happen in ordinary

THE VOICES OF NA TURE.

139

air, you must be standing at least 56 feet away from
the point from which the waves are reflected, for then
the second blow will come one-tenth of a second after
the first one, and that is long enough for you to feel
them separately.* Miss C. A. Martineau tells a story
of a dog which was terribly frightened by an echo.
Thinking another dog was barking, he ran forward to
meet him, and was very much astonished, when, as he
came nearer the wall, the echo ceased. I myself once
knew a case of this kind, and my dog, when he could
find no enemy, ran back barking, till he was a certain
distance off, and then the echo of course began again.
He grew so furious at last that we had great diffi-
culty in preventing him from flying at a strange man
who happened to be passing at the time.

Sometimes, in the mountains, walls of rock rise at
some distance one behind another, and then each one
will send back its echo a little later than the rock be-
fore it, so that the " Ha " which you give will come
back as a peal of laughter. There is an echo in Wood-
stock Park which repeats the word twenty times.
Again sometimes, as in the Alps, the sound-waves in
coming back rebound from mountain to mountain and
are driven backward and forward, becoming fainter
and fainter till they die away; these echoes are very
beautiful.

If you are now able to picture to yourselves one set
of waves going to the wall, and another set returning

* Sound travels 1120 feet in a second, in air of ordinary tem-
perature, and therefore 112 feet in the tenth of a second. There-
fore the journey of 56 feet beyond you to reach the wall and 56
feet to return, will occupy the sound-wave one-tenth of a second
and separate the two sounds.

I40 THE FAIRY-LAND OF SCIENCE.

and crossing them, you will be ready to understand
something of that very difficult question, How is it
that we can hear many different sounds at one time
and tell them apart ?

Have you ever watched the sea when its surface is
much ruffled, and noticed how, besides the big waves
of the tide, there are numberless smaller ripples made
by the wind blowing the surface of the water, or the
oars of a boat dipping in it, or even rain-drops falling?
If you have done this you will have seen that all
these waves and ripples cross each other, and you can
follow any one ripple with your eye as it goes on its
way undisturbed by the rest. Or you may make beau-
tiful crossing and recrossing ripples on a pond by
throwing in two stones at a little distance from each
other, and here too you can follow any one wave on
to the edge of the pond.

Now just in this way the waves of sound, in their
manner of moving, cross and recross each other. You
will remember too, that different sounds make waves
of different lengths, just as the tide makes a long wave
and the rain-drops tiny ones. Therefore each sound
falls with its own peculiar wave upon your ear, and
you can listen to that particular wave just as you look
at one particular ripple, and then the sound becomes
clear to you.

All this is what is going on outside your ear, but
what is happening in your ear itself? How do these
blows of the air speak to your brain? By means of
the following diagram, Fig. 35, we will try to under-
stand roughly our beautiful hearing instrument, the
ear.

THE VOICES OF NATUSE. 141

First, I want you to notice how beautifully the out-
side shell, or concha as it is called (a), is curved round
so that" any movement of the air coming to it from
the front is caught in it and reflected into the hole of

1
I

Fig. 35 — II. Concha, or shell of ihe ear. i r. Auditory canal,
f. Tympanic membrane alretched across the drum of the
ear. E, Eustachian tuhe. d, e. f. Ear-bones; d, the ham-
mer, malUus ; e, the anvil, incus; /, [he stirrup, staprs. L,
Labyrinth, g. Cochlea, or internal spiral shell, h. One of
the little windows ; the other is covered by the stirrup.

the ear. Put your finger round your ear and feel how
the gristly part is curved toward the front of your
head. This concha makes a curve much like the
curve a deaf man makes with his hand behind his ear
to catch the sound. Animals often have to raise their
ears to catch the sound well, but ours stand always

142 I^ME FAIRY^LAND OF SCIENCE.

ready. When the air-waves have passed in at the
hole of your ear, they move all the air in the passage,
hCy which is called the auditory, or hearing, canal.
This canal is lined with little hairs to keep out insects
and dust, and the wax which collects in it serves the
same purpose. But if too much wax collects, it pre-
vents the air from playing well upon the drum, and
therefore makes you deaf. Across the end of this
canal, at c, a membrane or skin called the tympanum
is stretched, like the parchment over the head of a
drum, and it is this membrane which moves to and
fro as the air-waves strike on it. A violent box on
the ear will sometimes break this delicate membrane,
or injure it, and therefore it is very wrong to hit a
person violently on the ear.

On the other side of this membrane, inside the ear,
there is air, which fills the whole of the inner chamber
and the tube E, which runs down into the throat be-
hind the nose, and is called the Eustachian tube after
the man who discovered it. This tube is closed at the
end by a valve which opens and shuts. If you breathe
out strongly, and then shut your mouth and swallow,
you will hear a little " click " in your ear. This is
because in swallowing you draw the air out of the
Eustachian tube and so draw in the membrane r, which
clicks as it goes back again. But unless you do this
the tube and the whole chamber cavity behind the
membrane remains full of air.

Now, as this membrane is driven to and fro by the
sound-waves, it naturally shakes the air in the cavity
behind it, and it also sets moving three most curious
little bones. The first of these bones d is fastened

THE VOICES OF NA TURE. 143

to the middle of the drumhead so that it moves to
and fro every time this membrane quivers. The head
of this bone fits into a hole in the next bone e, the
anvil, and is fastened to it by muscles, so as to drag it
along with it; but, the muscles being elastic, it can
draw back a little from the anvil, and so give it a blow
each time it comes back. This anvil e, is in its turn
very firmly fixed to the little bone /, shaped like a
stirrup, which you see at the end of the chain.

This stirrup rests upon a cimous body L, which
looks in the diagram like a snail-shell with tubes
coming out of it. This body, which is called the
labyrinth, is made of bone, but it has two little win-
dows in it, one h covered only bv a membrane, while
the other has the head of the stirrup / resting upon it.

Now, with a little attention you wdll understand
that when the air in the canal be shakes the drum-
head c to and fro, this membrane must drag with it
the hammer, the anvil, and the stirrup. Each time
the drum goes in, the hammer will hit the anvil, and
drive the stirrup against the little window; every time
it goes out it will draw the hammer, the anvil, and the
stirrup out again, ready for another blow. Thus the
stirrup is always playing upon this little window.
Meanwhile, inside the bony labyrinth L there is a
fluid like water, and along the little passages arc very
fine hairs, which wave to and fro like reeds ; and when-
ever the stirrup hits at the little window, the fluid
moves these hairs to and fro, and they irritate the
ends of a nerve t, and this nerve carries the message
to your brain. There are also some curious little
stones called otoliths, lying in some parts of this fluid

144 ^^^ FAIRY'LAXD OF SCIENCE.

and they, by their rolling to and fro, probably keep
up the motion and prolong the sound.

You must not imagine we have explained here the
many intricacies which occur in the ear; I can only
hope to give you a rough idea of it, so that you may
picture to yourselves the air-waves mo^nng (as in Fig.
34) backward and forward in the canal of your ear,
then the tympanum vibrating to and fro, the hammer
hitting the anvil, the stirrup knocking at the little
window, the fluid waving the fine hairs and rolling
the tiny stones, the ends of the ner\'e quivering, and
then {hozs: we know not) the brain hearing the message.

Is not this wonderful, going on as it does at every
sound vou hear? And vet this is not all, for inside
that curled part of the labyrinth g^ which looks like a
snail-shell and is called the cochlcOy there is a most
wonderful apparatus of more than three thousand fine
stretched filaments or threads, and these act like the
strings of a harp, and make you hear different tones.
If you go near to a harp or a piano, and sing any
particular note very loudly, you will hear this note
sounding in the instrument, because you will set just
that particular string quivering, which gives the note
you sang. The air- waves set going by your voice
touch that string, because it can quiver in time with
them, while none of the other strings can do so. Now,
just in the same way the tiny instrument of three
thousand strings in your ear, which is called Corti's
organ, vibrates to the air-waves, one thread to one set
of waves, and another to another, and according to
the fibre that quivers, will be the sound you hear.
Here then, at last, we see how nature speaks to us.

THE VOICES OF NATURE.

'45

All the movements going on outside, however violent
and varied they may be, cannot of themselves make
sound. But here, in the little space behind the drum
of our ear, the air-waves are sorted and sent on to our
brain, where they speak to us as sound.

But why then do we not hear all sounds as music?
Why are some mere noise, and others clear musical
notes? This depends entirely upon whether the
sound-waves come quickly and regularly, or by an
irregular succession of shocks. For example, when a
load of stones is being shot out of a cart, you hear
only a long, continuous noise, because the stones fall
irregularly, some quicker, some slower, here a number
together, and there two or three stragglers by them-
selves; each of these different shocks comes to yoiu*
ear and makes a confused, noisy sound. But if you
run a stick very quickly along a paling, you will hear
a sound very like a musical note. This is because the
rods of the paling are all at equal distances one from
the other, and so the shocks fall quickly one after an-
other at regular intervals upon your ear. Any quick
and regular succession of sounds makes a note, even
though it may be an ugly one. The squeak of a slate
pencil along a slate, and the shriek of a railway whistle
are not pleasant, but they are real notes which you
could copy on a violin.

I have here a simple apparatus which I have had
made to show you that rapid and regular shocks pro-
duce a natural musical note. This wheel (Fig. 36) is
milled at the edge like a quarter of a dollar, and when
I turn it rapidly so that it strikes against the edge of

■11 mr b-arn'* ^
'iigtMi. Thii i*

ifcrvc wa***, wUbr i

eft

r G fori: makes ]
Tilr nro. ^\TiT
\irk moves three

tkmt tt»dcwar4 aot) iorAaj-i Khilc the prong of the

THE VOICES OF NATURE.

C fork only moves twice; therefore the G fork does
not crowd so many atoms together before it draws
back, and the waves are shorter. These two notes, C
and G, are a fifth of an octave apart; if we had two

Fig. 37.

forks, of which one went twice as fast as the other,
making four waves while the other made two, then
that note would be an octave higher.

So we see that all the sounds we hear — the warning
noises which keep us from harm, the beautiful musical
notes with all the tunes and harmonies that delight
us, even the power of hearing the voices of those we
love, and learning from one another that which each
can tell — all these depend upon the invisible waves of
air, even as the pleasures of light depend on the waves
of ether. It is by these sound-waves that nature
speaks to us, and in all her movements there is a
reason why her voice is sharp or tender, loud or gentle,
awful or loving. Take for instance the brook we
spoke of at the beginning of the lecture. Why does
it sing so sweetly, while the wide deep river makes

148 ^y/iS FAIRY-LAND OF SCIENCE.

no noise? Because the little brook eddies and purls
round the stones, hitting them as it passes; sometimes
the water falls down a large stone, and strikes against
the water below ; or sometimes it grates the little peb-
bles together as they lie in its bed. Each of these blows
makes a small globe of sound-waves, which spread and
spread till they fall on your ear, and because they fall
quickly and regularly, they make a low, musical note.
We might almost fancy that the brook wished to show
how joyfully it flows along, recalling Shelley's beauti-
ful lines: —

*' Sometimes it fell
Among the moss with hollow harmony,
Dark and profound ; now on the polished stones
It danced ; like childhood laughing as it went."

The broad deep river, on the contrary, makes none
of these cascades and commotions. The only places
against which it rubs are the banks and the bottom;
and here you can sometimes hear it grating the par-
ticles of sand against each other if you listen very
carefully. But there is another reason why falling
water makes a sound, and often even a loud roaring
noise in the cataract and in the breaking waves of the
sea. You do not only hear the water dashing against
the rocky ledges or on the beach, you also hear the
bursting of innumerable little bladders of air which
arc contained in the water. As each of these bladders
is dashed on the ground, it explodes and sends sound-
waves to your ear. Listen to the sea some day when
the waves are high and stormy, and you cannot fail
to be struck by the irregular bursts of sound.

The weaves, however, do not only roar as they dash

THE VOICES OF NA TURE.

on the ground ; I
to scream as the_v
sott'-caits it,
"TljEScreamof/hti

ed liow they seem
ci..-;i^:irr' Tenny-

by the

■ Seating against each

II down/ Dr. Tj*ndall

w the size of the stones

If they are large, it

and it is Cioised li) Hi.; -tii
other a*vth'c waves diag il
tells us tffat it i^s possible to k
by thajfeind of noise they m,

; when smaller, a kind of s

a(^ will protUice a mer j hiss,

luH hy the siae of a brook, a water-

'hilehe can lisfen for sounds like these,

iniself how they are being made? You

number of other causes of sound made

m once pay attention to them.

NorTs it only water that sinjjs ;to us. Listen to

the wind, how sweetly it sighs .drnong the leaves.

Therejive hear it. heeausc it. rubs the leaves together,

and thjey ])i*duce tJie sound-waves. Bnfwalk against

the \wlnd some day and yon can lieat- it whistling in

your own ear, striking against the curved cup, and

setting, up a succession Df waves in the hearing

■tl-
■, canal of tWe e;
Win-
all kinds

■ itself.

hen

I glas^ jfiT^ill answer our question rbiighly.
If I strikejariMffining-fork and hold it over the jar,
you can flmnear it, because the sound is feeble, but it
I fill the jar gently with water, when the water rises
to a certain point you will hear a loud clear note, be-

I50 "?£ FAIRY-LAWD OF SCIENCE.

cause the waves of air in the jar are exactly the right
length to answer to the note of the fork. If I now
blow across the mouth of the jar you hear the same
note, showing that a cavity of a particular length will
only sound to the waves which fit it. Do you see now
the reason why pan-pipes give different sounds, or
even the hole at the end of a common key when you
blow across it? Here
is a subject you will
find very interesting if
you will read about it,
for I can only just sug-
gest it here. But now
you will see that the
canal of your ear also
answers only to certain
waves, and so the wind
sings in your ear with
a real if not a musical

Again, on a windy night have you not heard the
wind sounding a wild, sad note down a valley? Why
do ymi think it sounds so much louder and more mu-
.sical here than when it is blowing across the plain?
lU'iMuse the air in the valley will only answer to a
certain set of waves, and, like the pan-pipe, gives a
particular nolo as the wind blows across it, and these
waves go lip and down the valley in rcgidar pulses,
making a wilil howl, ^'on may hear the same in the
cltinniey, or in the keyhole: all these are waves set up
in the luile across which the wind blows. Even the
music ill the shell which you hold to your ear is made

THE VOICES OE NATURE.

151

by the air in the shell pulsating to and fro. And how
do you think it is set going? By the throbbing of the
veins in your own ear, which causes the air in the shell
to vibrate.

Another grand voice of nature is the thunder.
People often have a vague idea that thunder is pro-
duced by the clouds knocking together, which is very
absurd, if you remember that clouds are but water-
dust. The most probable explanation of thunder is
much more beautiful than this. You will remember
from Lecture III that heat forces the air-atoms apart.
Now, when a flash of lightning crosses the sky it sud-
denly expands the air all round it as it passes, so that
globe after globe of sound-waves is formed at every
point across which the lightning travels. Now light,
you remember, travels with such wonderful rapidity
(192,000 miles in a second) that a flash of lightning is
seen by us and is over in a second, even when it is two
or three miles long. But sound comes slowly, taking
five seconds to travel half a mile, and so all the sound-
waves at each point of the two or three miles fall on
our ear one after the other, and make the rolling thun-
der. Sometimes the roll is made even longer by the
echo, as the sound-waves are reflected to and fro by
the clouds on their road; and in the mountains we
know how the peals echo and re-echo till they die
away.

We might fill up far more than an hour in speak-
ing of those voices which come to us as nature is at
work. Think of the patter of the rain, how each drop
as it hits the pavement sends circles of sound-waves
out on all sides; or the loud report which falls on the

/.:■.-' u- ::it rianiT cracks on its
:- ::i-. niiriiT; "ri:»:»n: of the ava-
.:■- :: :v.urt niii.s=*tr.> C'C the side
i^-L.-: an:, l.'! :•: ihe>e create
: - -::::iL i:>iii :>r I'eeMe. which
.-.■.• • .:- aiK. :ivr:>r:n converted

:\r.K n »v iu>: ::• glance at

:•— ; ;.-; >, r.Mjr.y arcmnd us.

..- . '•.\\~7.:r\^ Lf '.Tit CTat. the

'..:>.■" ^.i: ": ; :hr beatings

..- «:* TTii-T r*i*.'.'jr in^a^fine.

.w \ ■ „,^-.^« ^ ^.-^ Vr"'T hv

. »

r.ir:; \\-3ng"s

■■■ .•^-. \ r.irr. lt-: toothed

•',:• v-.rcj- r--j:'ve the

. ,M ■ 1 . >. ;. p . . :iu \\-i:l now

'•, '.K.i.r.Sii :■: :r.e gnat

I i"

': iic^r ne

N >

• ■ ■ ... . ». » >."'.■■" .".-V\ ,-,vcs.

.. N ^ ■ ^ -^ ........... .'., ^

X • • . . ■. - •

>• .>s , >,\ ,> i:v '.•',:/.- >\ cr«.\\:::rc> \v;'.:o:i

- ^ \s '*- >:Vdv X'.: :>.<' s\\vv:cs: sounds of all

. ...\\N .i.^' :>.o \o.x\s o: :ho birvls. All voice-

THE VOICES OF NATURE,

153

sounds are made by two elastic bands or cushions,
called vocal chords, stretched across the end of the
tube or windpipe through which we breathe, and as
we send the air through them we tig^hten or loosen
them as we will, and so make them vibrate quickly or
slowly and make sound-waves of different lengths.
But if you will try some day in the woods you will
find that a bird can beat you over and over again in
the length of his note; when you are out of breath
and forced to stop he will go on with his merry trill
as fresh and clear as if he had only just begun. This
is because birds can draw air into the whole of their
body, and they have a large stock laid up in the folds
of their windpipe, and besides this the air-chamber
behind their elastic bands or vocal chords has two
compartments where we have only one, and the second
compartment has special muscles by which they can
open and shut it, and so prolong the trill.

Only think what a rapid succession of waves must
quiver through the air as a tiny lark agitates his little
throat and pours forth a volume of song! The next
time you are in the country in the spring, spend half
an hour listening to him, and try and picture to your-
self how that little being is moving all the atmosphere
round him. Then dream for a little while about sound,
what it is, how marvellously it works outside in the
world, and inside in your ear and brain; and then,
when you go back to work again, you will hardly
deny that it is well worth while to listen sometimes to
the voices of nature and ponder how it is that we hear
them.

THE FAIRY-LAND OF SCIEffCE.

LECTURE VII.

THE LIFE OF A PRIMROSE.

^HEN the dreary
days of winter and
the early damp
days of spring
are passing
away, and the
warm bright
sunshine has
begun to pour
down upon the
grassy paths of
the wood, who
does not love to
go out and bring home
bouquets of violets.and
W\wMU. and primroses ? We wander from one plant
In AiHttlirr, picking a flower here and a bud there, as
Uw.y »r»llr among the green leaves, and we make our
ihHHtls nw-wl ami gay with the tender and lovely blos-
9C^\%- Hut tell nif . did you ever stop to think, as you
^^^V^^^I iKwfr alter flower to your bouquet, !iow the
t<>lAtiU wlilcU I)«*ar them have been building up their
RTv¥H ImWh and llicir fragile buds during the last few
ftW^»? It \iHi had visited the same spot a month be-
ftwv, » {"pw v>( last year's leaves, withered and dead,

THE LIFE OF A PRIMROSE,

155

would have been all that you would have found. And
now the whole wood is carpeted with delicate green
leaves, with nodding bluebells, and pale-yellow prim-
roses, as if a fairy had touched the ground and covered
it with fresh young life. And our fairies have been at
work here; the fairy " Life," of whom we know so
little, though we love her so well and rejoice in the
beautiful forms she can produce; the fairy sunbeams
with their invisible influence kissing the tiny shoots
and warming them into vigour and activity ; the gentle
rain-drops, the balmy air, all these have been working,
while you or I passed heedlessly by ; and now we come
and gather the flowers they have made, and too often
forget to wonder how these lovely forms have sprung
up around us.

Our work during the next hour will be to consider
this question. You were asked last week to bring
with you to-day a primrose-flower, or a whole plant if
possible, in order the better to follow out with me the
" Life of a Primrose." * This is a very different kind
of subject from those of our former lectures. There
we took world-wide histories ; we travelled up to the
sun, or round the earth, or into the air; now I only
ask you to fix your attention on one little plant, and
inquire into its history.

There is a beautiful little poem by Tennyson, which
says —

" Flower in the crannied wall,
I pluck you out of the crannies ;

* To enjoy this lecture, the child ought to have, if possible,
a primrose-flower, an almond soaked for a few minutes in hot
water, and a piece of orange.

156 THE FAIRY'LAND OF SCIENCE.

Hold you here, root and all, in my hand.
Little flower ; but if I could understand
What you are, root and all, and all in all,
I should know what God and man is."

We cannot learn all about this little flower, but we
can learn enough to understand that it has a real sepa-
rate life of its own, well worth knowing. For a plant
is born, breathes, sleeps, feeds, and digests just as
truly as an animal does, though in a different way.
It works hard both for itself to get its food, and for
others in making the air pure and fit for animals to
breathe. It often lays by provision for the winter.
It sends young plants out, as parents send their chil-
dren, to fight for themselves in the world; and then,
after living sometimes to a good old age, it dies, and
leaves its place to others.

We will try to follow out something of this life to-
day; and first, we will begin with the seed.

I have here a package of primrose-seeds, but they
are so small that we cannot examine them ; so I have
also had given to each one of you an almond-kernel,
which is the seed of the almond-tree, and which has
been soaked, so that it splits in half easily. From
this we can learn about seeds in general, and then ap-
ply it to the primrose.

If you peel the two skins off your almond-seed (the
thick, brown, outside skin, and the thin, transparent
one under it), the two halves of the almond will slip
apart quite easily. One of these halves will have a
small dent at the pointed end, while in the other half
you will see a little lump, which fitted into the dent
when the two halves were joined. This little lump

THE LIFE OF A PRIMROSE,

157

(a &, Fig. 39) is a young plant, and the two halves of
the almond are the seed-leaves which hold the plantlet,
and feed it till it can feed itself. The rounded end
of the plantlet (fr) sticking out of the al-
mond, is the beginning of the root, while
the other end (a) will in time become the
stem. If you look carefully, you will see
two little points at this end, which are
the tips of future leaves. Only think how
minute this plantlet must be in a prim-
rose, where the whole seed is scarcely
larger than a grain of sand ! Yet in this Fig. 39.— Half
tiny plantlet lies hid the life of the future ^" almond,
plant.

When the seed falls intp the ground,
so long as the earth is cold and dry, it
lies like a person in a trance, as if it were
dead; but as soon as the warm, damp
spring comes, and the busy little sun-waves pierce
down into the earth, they wake up the plantlet, and
make it bestir itself. They agitate to and fro the par-
ticles of matter in this tiny body, and cause them to
seek out for other particles to seize and join to them-
selves.

But these new particles can not come in at the
roots, for the seed has none; nor through the leaves,
for they have not yet grown up; and so the plantlet
begins by helping itself to the store of food laid up in
the thick seed-leaves in which it is buried. Here it
finds starch, oils, sugar, and substances called albu-
minoids — ^the sticky matter which you notice in wheat-
grains when you chew them is one of the albumi-

showing the
plantlet. a,
Rudiment of
stem. ^, Be-
ginning of
root.

Fic. 40. — Juicy cells in a piece
of orange.

158 THE FAIRY-LAND OF SCIENCE.

noids. This food is all ready for the plantlet to use,
and it sucks it in, and works itself into a young plant
with tiny roots at one end, and a growing shoot, with
leaves, at the other.

But how does it grow? What makes it become
lai^r? To answer this, you must look at the second
thing I asked you to bring
— a piece of orange. If
you take the skin off a
piece of orange, you will
see inside a number of
long- shaped transparent
bags, full of juice. These we call ceils, and the flesh
of all plants and animals is made up of cells like these,
onlyof various shapes.
In the pith of elder
they are round, large,
and easily seen (a.
Fig. 41); in the stalks
of plants they are
long, and lap over
each other ((>, Fig.
41), so as to give
the stalk strength to
stand upright. Some-
times many cells
growing one on the

top of the other. Fig. 41,— Plant-celU. a, Round cells
break into one tube in P'th of elder. *, Long cells
and make vessels. '" ^*'"' °^ " P'^"'-
But whether large or small, they are all bags grow-
ing one against the other.

Plant-cells.

THE LIFE OF A PRIMROSE. 159

In the orange-pulp these cells contain only sweet
juice, but in other parts of the orange-tree or any
other plant they contain a sticky substance with little
grains in it. This substance is called " protoplasm/'
or the iirst form of life, for it is alive and active, and
under a microscope you may see in a living plant
streams of the little grains moving about in the cells.

Now we are prepared to explain how our plant
grows. Imagine the tiny primrose plantlet to be made
up of cells filled with active living protoplasm, which
drinks in starch and other food from the seed-leaves.
In this way each cell will grow too full for its skin,
and then the protoplasm divides into two parts and
builds up a wall between them, and so one cell be-
comes two. Each of these two cells again breaks up
into two more, and so the plant grows larger and
larger, till by the time it has used up all the food in
the seed-leaves, it has sent roots covered with fine
hairs downward into the earth, and a shoot with be-
ginnings of leaves up into the air.

Sometimes the seed-leaves themselves come above
ground, as in the mustard-plant, and sometimes they
are left empty behind, while the plantlet shoots through
them.

And now the plant can no longer afford to be idle
and live on prepared food. It must work for itself.
Until now it has been taking in the same kind of
food that you and I do; for we too find many seeds
very pleasant to eat and useful to nourish us. But
now this store is exhausted. Upon what then is the
plant to live? It is cleverer than we are in this, for
while we cannot live unless we have food which has

l6o THE FAIRY-LAND OF SCIENCE,

once been alive, plants can feed upon gases and water
and mineral matter only. Think over the substances
you can eat or drink, and you will find they are nearly
all made of things which have been alive : meat, vege-
tables, bread, beer, wine, milk; all these are made
from living matter, and though you do take in such
things as water and salt, and even iron and phos-
phorus, these would be quite useless if you did not eat
and drink prepared food which your body can work
up into living matter.

But the plant, as soon as it has roots and leaves,
begins to make living matter out of matter that has
never been alive. Through all the little hairs of its
roots it sucks in water, and in this water are dissolved
more or less of the salts of ammonia, phosphorus, sul-
phur, iron, lime, magnesia, and even silica, or flint.
In all kinds of earth there is some iron, and we shall
see presently that this is very important to the plant.

Suppose, then, that our primrose has begun to
drink in water at its roots. How is it to get this
water up into the stem and leaves, seeing that the
whole plant is made of closed bags or cells? It does
it in a very curious way, which you can prove for your-
selves. Whenever two fluids, one thicker than the
other, such as molasses and water for example, are
only separated by a skin or any porous substance, they
will always mix, the thinner one oozing through the
skin into the thicker one. If you tie a piece of bladder
over a glass tube, fill the tube half-full of molasses, and
then let the covered end rest in a bottle of water, in
a few hours the water will get in to the molasses and
the mixture will rise up in the tube till it flows over the

THE LIFE OF A PRIMROSE. jgl

top. Now, the saps and juices of plants are thicker
than water, so, directly the water enters the cells at
the root it oozes up into the cells above, and mixes
with the sap. Then the matter in those cells becomes
thinner than in the cells above, so it too oozes up,
and in this way cell by cell the water is pumped up
into the leaves.

When it gets there it finds our old friends the sun-
beams hard at work. If you have ever tried to grow
a plant in a cellar, you will know that in the dark its
leaves remain white and sickly. It is only in the sun-
light that a beautiful delicate green tint is given to
them, and you will remember from Lecture II that
this green tint shows that the leaf has used all the
sun- waves except those which make you see green;
but why should it do this only when it has grown up
in the sunshine?

The reason is this: when the sunbeam darts into
the leaf and sets all its particles quivering, it divides
the protoplasm into two kinds, collected into different
cells. One of these remains white, but the other kind,
near the surface, is altered by the sunlight and by the
help of the iron brought in by the water. This par-
ticular kind of protoplasm, which is called " chloro-
phyll,'* will have nothing to do with the green waves
and throws them back, so that every little grain of
this protoplasm looks green and gives the leaf its
green colour.

It is these little green cells that by the help of the
sun-waves digest the food of the plant and turn the
water and gases into useful sap and juices. We saw
in Lecture III that when we breathe-in air, we use

r
I

THE FAIRY-LAKTD OF SCIENCE.

162

up the oxygen in it and send back out of our mouths
carbonic acid, which is a gas made of oxygen and
carbon.

Now, every living thing wants carbon to feed upon,
but plants cannot take it in my itself, because carbon
is solid (the blacklead in your pencils is pure carbon),
and a plant cannot eat, it can only drink-in fluids and
gases. Here the little green cells help it out of its
difficulty. They take in
or absorb out of the air
the carbonic-acid gas
which we have given out
of our mouths, and then
by the help of the sun-
waves they tear the car-
bon and oxygen apart.
F,a. 4z.-0«,g=n.b.bbl., rising j, , |^ ^

from laurel-leaves in water. ■'^ •'

throw back into the air
for us to use, but the carbon they keep.

If you will take some fresh laurel-leaves and put
them into a tumbler of water turned upside-down in
a saucer of water, and set the tumbler in the sunshine,
you will soon see little bright bubbles rising up and
clinging to the glass. These are bubbles of oxygen
gas, and they tell you that they have betn set free by
the green cells which have torn from them the carbon
of the carbonic acid in the water.

But what becomes of the carbon? And what use
is made of the water which we have kept waiting all
this time in the leaves? Water, you already know,
is made of hydrogen and oxygen; but perhaps you
will be surprised when I tell you that starch, sugar.

THE LIFE OF A PRIMROSE. 163

and oil, which we get from plants, are nothing more
than hydrogen and oxygen in different quantities
joined to carbon.

It is very difficult at first to picture such a black
thing as carbon making part of delicate leaves and
beautiful flowers, and still more of pure white sugar.
But we can make an experiment by which we can
draw the hydrogen and oxygen out of common loaf
sugar, and then you will see the carbon stand out in
all its blackness. I have here a plate with a heap of
white sugar in it. I pour upon it first some hot water
to melt and warm it, and
then some strong sulphuric
acid. This acid does noth-
ing more than simply draw
the hydrogen and oxygen F^^- 43.-Carbon rising up
o • • r ^ from white sugar.

out. bee ! m a few moments

a black mass of carbon begins to rise, all of which
has come out of the white sugar you saw just now.*
You see, then, that from the whitest substance in
plants we can get this black carbon; and in truth,
one-half of the dry part of every plant is composed
of it.

Now look at my plant again, and tell me if we have
not already found a curious history? Fancy that you
see the water creeping in at the roots, oozing up from
cell to cell till it reaches the leaves, and there meet-

* The common dilute sulphuric acid of commerce is not strong
enough for this experiment, and any child who wants to get pure
sulphuric acid must take some elder person with him, otherwise
the chemist will not sell it to him. Great care must be taken in
using it, as it burns everything it touches.
12

164 THE FAIRY-LAXD OF SCIEXCE.

ing the carbon which has just come out of the air, and
being worked up with it by the sun-waves into starch,
or sugar, or oils.

But meanwhile, how is new protoplasm to be
formed? for without this active substance none of the
work can go on. Here comes into use a lazy gas
we spoke of in Lecture III. There we thought that
nitrogen was of no use except to float oxygen in the
air, but here we shall find it very useful. So far as
we know, plants cannot take up nitrogen out of the
air, but they can get it out of the ammonia which the
water brings in at their roots.

Ammonia, you will remember, is a strong-smelling
gas, made of hydrogen and nitrogen, and which is
often almost stifling near a manure-heap. When you
manure a plant you help it to get this ammonia, but
at any time it gets some from the soil and also from
the rain-drops which bring it down in the air. Out
of this ammonia the plant takes the nitrogen and
works it up with the three elements', carbon, oxygen,
and hydrogen, to make the substances called albumi-
noids, which form a large part of the food of the
plant, and it is these albuminoids which go to make
protoplasm. You will notice that while the starch and
other substances are only made of three elements, the
active protoplasm is made of these three added to a
fourth, nitrogen, and it also contains phosphorus and
sulphur.

And so hour after hour and day after day our prim-
rose goes on pumping up water and ammonia from
its roots to its leaves, drinking in carbonic acid from
the air, and using the sun-waves to work them all up

THE LIFE OF A PRIMROSE. 165

into food to be sent to all parts of its body. In this
way these leaves act, you see, as the stomach of the
plant, and digest its food.

Sometimes more water is drawn up into the leaves
than can be used, and then the leaf opens thousands
of little mouths in the skin of its under surface, which
let the drops out just as drops of perspiration ooze
through our skin when we are overheated. These
little mouths, which are called stomates (a. Fig. 44),
are made of two flattened cells, fit-
ting against each other. When the
air is damp and the plant has too
much water these lie open and let it
out, but when the air is dry. and ,
the plant wants to keep as much
water as it can, then they are closely
shut. There are as many as a hun- f'« ^^^2 "^'^
dred thousand of these mouths
under one apple-leaf, so you may imagine how small
they often are.

Plants which only live one year, such as migno-
nette, the sweet pea, and the poppy, take in just enough
food to supply their daily wants and to make the seeds
we shall speak of presently. Then, as soon as their
seeds are ripe their roots begin to shrivel, and water
is no longer carried up. The green cells can no longer
get food to digest, and they themselves are broken
up by the sunbeams and turn yellow, and the plant dies.

But many plants are more industrious than the
sweet pea and mignonette, and lay by store for another
year, and our primrose is one of these. Look at this
thick solid mass below the primrose leaves, out of

l66 THE FAIRY^LAND OF SCIENCE,

which the roots spring. This is really the stem of
the primrose hidden underground, and all the starch,
albuminoids, etc., which the plant can spare as it
grows, are sent down into this underground stem and
stored up there, to lie quietly in the ground through
the long winter, and then when the warm spring comes
this stem begins to send out leaves for a new plant.

We have now seen how a plant springs up, feeds
itself, grows, stores up food, withers, and dies; but we
have said nothing yet about its beautiful flowers or
how it forms its seeds. If we look down close to the
bottom of the leaves in a primrose root in spring-time,
we shall always find three or four little green buds
nestling in among the leaves, and day by day we may
see the stalk of these buds lengthening till they reach
up into the open sunshine, and then the flower opens
and shows its beautiful pale-yellow crown.

We all know that seeds are formed in the flower,
and that the seeds are necessary to grow into new
plants. But do we know the history of how they are
formed, or what is the use of the different parts of
the bud? Let us examine them all, and then I think
you will agree with me that this is not the least won-
derful part of the plant.

Remember that the seed is the one important thing,
and then notice how the flower protects it. First, look
at the outside green covering, which we call the calyx.
See how closely it fits in the bud, so that no insects
can creep in to gnaw the flower, nor any harm come
to it from cold or blight. Then, when the calyx opens,
notice that the yellow leaves which form the crown or

THE LIFE OF A PRIMROSE.

167

corolla, are each alternate with one of the calyx leaves,
so that anything which got past the first covering
would be stopped by the second. Lastly, when the
delicate corolla has opened out, look at those curious
yellow bags just at the top of the tube (b, 2, Fig, 45).
What is their use?

Fig. 45. — The two forms of the Primrose-flower, a, Stigma or
sticky head of the seed-vessel. ^, Anthers of the stamens,
r, Corolla or crown of the flower, c/, Calyx or outer cover-
ing, sv, Seed-vessel. A, Enlarged pistil, with pollen-grain
resting on the stigma and growing dow^n to the ovule.
o. Ovules.

But I fancy I see two or three little questioning
faces which seem to say, ** I see no yellow bags at
the top of the tube." Well, I cannot tell whether
you can or not in the specimen you have in your
hand; for one of the most curious things about prim-
rose flowers is, that some of them have these yellow
bags at the top of the tube and some of them hidden
down right in the middle. But this I can tell you:
those of you who have got no yellow bags at the top
will have a round knob there (i a, Fig. 45), and will
find the yellow bags (^) buried in the tube. Those,

1 68 THE FAIRY'LAND OF SCIENCE.

on the other hand, who have the yellow bags (2 6,
Fig. 45) at the top will find the knob (a) half-way
down the tube.

Now for the use of these yellow bags, which are
called the anthers of the stamens, the stalk on which
they grow being called the filament or thread. If you
can manage to split them open you will find that they
have a yellow powder in them, called pollen, the same
as the powder which sticks to your nose when you
put it into a lily; and if you look with a magnifying
glass at the little green knob in the centre of the
flower you will probably see some of this yellow dust
sticking on it (A, Fig. 45). We will leave it there
for a time, and examine the body called the pistil, to
which the knob belongs. Pull off the yellow corolla
(which will come off quite easily), and turn back the
green leaves. You will then see that the knob stands
on the top of a column, and at the bottom of this col-
umn there is a round ball (sz'), which is a vessel for
holding the seeds. In this diagram (A, Fig. 45) I
have drawn the whole of this curious ball and column
as if cut in half, so that we may see what is in it. In
the middle of the ball, in a cluster, there are a number
of round transparent little bodies, looking something
like round green orange-cells full of juice. They are
really cells full of protoplasm, with one little dark
spot in each of them, which by-and-by is to make our
little plantlet that we found in the seed.

" These, then, are seeds," you will say. Not yet ;
they are only ovules, or little bodies which may be-
come seeds. If they were left as they are they would
all wither and die. But those little yellow grains of

THE LIFE OF A PRIMROSE. 169

pollen, which we saw sticking to the knob at the top,
are coming down to help them. As soon as these yel-
low grains touch the sticky knob or stigma, as it is
called, they throw out tubes, which grow down the col-
umn until they reach the ovules. In each one of these
they find a tiny hole, and into this they creep, and then
they pour into the ovule all the protoplasm from the
pollen-grain which is sticking above, and this enables
it to grow into a real seed, with a tiny plantlet inside.

This is how the plant forms its seed to bring up
new little ones next year, while the leaves and^the roots
are at work preparing the necessary food. Think
sometimes when you walk in the woods, how hard
at work the little plants and big trees are, all around
you. You breathe in the nice fresh oxygen they have
been throwing out, and little think that it is they who
are making the country so fresh and pleasant, and
that while they look as if they were doing nothing
but enjoying the bright sunshine, they are really ful-
filling their part in the world by the help of this sun-
shine; earning their food from the ground; working
it up; turning their leaves where they can best get
light (and in this it is chiefly the violet sun-waves that
help them), growing, even at night, by making new
cells out of the food they have taken in the day; stor-
ing up for the winter; putting out their flowers and
making their seeds, and all the while smiling so pleas-
antly in quiet nooks and sunny dells that it makes us
glad to see them.

But why should the primroses have such golden
crowns? plain green ones would protect the seed quite
as well. Ah! now we come to a secret well. worth

I70 ^'^^ FAIRY-LAND OF SCIENCE.

knowing. Look at the two primrose flowers, i and 2,
Fig- 45 > P- 167, and tell me how you think the dust
gets on to the top of the sticky knob or stigma. No.
2 seems easy enough to explain, for it looks as if the
pollen could fall down easily from the stamens on to
the knob, but it cannot fall up, as it would have to do
in No. I. Now the curious truth is, as Mr. Darwin
has shown, that neither of these flowers can get the
dust easily for themselves, but of the two No. i has
the least difficulty.

Look at a withered primrose, and see how it holds
its head down, and after a little while the yellow crown
falls off. It is just about as it is falling that the
anthers or bags of the stamens burst open, and then,
in No. I (Fig. 46), they are dragged over the knob

Fig. 46. — Corolla of Primrose falling off. i, Primrose with long
pistil, and stamens in the tube, same as i of Fig. 45. 2,
Primrose with short pistil, and stamens at mouth of tube, 2,
Fig. 45.

and some of the grains stick there. But in the other
form of primrose. No. 2, when the flower falls off, the
stamens do not come near the knob, so it has no chance
of getting any pollen; and while the primrose is up-

THE LIFE OF A PRIMROSE.

171

right the tube is so narrow "that the dust does not
easily fall. But, as I have said, neither kind gets it
very easily, nor is it good for them if they do. The
seeds are much stronger and better if the dust or pol-
len of one flower is carried away and left on the knob
or stigma of another flower; and the only way this
can be done is by insects flying from one flower to an-
other and carrying the dust on their legs and bodies.

If you suck the end of the tube of the primrose
flower you will find it tastes sweet, because a drop of
honey has been lying there. When the insects go in
to get this honey, they brush themselves against the
yellow dust-bags, and sOme of the dust sticks to them,
and then when they go to the next flower they rub it
off on to its sticky knob.

Look at No. i and No. 2 (Fig. 45) and you will see
at once that if an insect goes into No. i and the pollen
sticks to him, when he goes into No. 2 just that part
of his body on which the pollen is will touch the
knob; and so the flowers become what we call
" crossed," that is, the pollen-dust of the one feeds the
ovule of the other. And just the same thing will hap-
pen if he flies from No. 2 to No. i. There the dust
will be just in the position to touch the knob which
sticks out of the flower.

Therefore, we can see clearly that it is good for the
primrose that bees and other insects should come to
it, and anything it can do to entice them will be use-
ful. Now, do you not think that when an insect once
knew that the pale-yellow crown showed where honey
was to be found, he would soon spy these crowns out
as he flew along? or if they were behind a hedge, and

1/2

THE FAIRY^LAND OF SCIENCE,

he could not see them, would not the sweet scent tell
him where to come and look for them? And so we
see that the pretty sweet-scented corolla is not only
delightful for us to look at and to smell, but it is
really very useful in helping the primrose to make
strong healthy seeds out of which the young plants
are to grow next year.

And now let us see what we have learned. We be-
gan with a tiny seed, though we did not then know
how this seed had been made. We saw the plantlet
buried in it, and learned how it fed at first on prepared
food, but soon began to make living matter for itself
out of gases taken from the water and the air. How
ingeniously it pumped up the water through the cells
to its stomach — the leaves! And how marvellously
the sun-waves entering there formed the little green
granules, and then helped them to make food and
living protoplasm ! At this point we might have gone
further, and studied how the fibres and all the different
vessels of the plant are formed, and a wondrous his-
tory it would have been. But it was too long for one
hour's lecture, and you must read it for yourselves in
books on botany. We had to pass on to the flower,
and learn the use of the covering leaves, the gaily col-
oured crown attracting the insects, the dust-bags hold-
ing the pollen, the little ovules each with the germ
of a new plantlet, lying hidden in the seed-vessel, wait-
ing for the pollen-grains to grow down to them.
Lastly, when the pollen crept in at the tiny opening
we learned that the ovule had now all it wanted to
grow into a perfect seed.

THE LIFE OF A PRIMROSE,

173

And so we came back to a primrose seed, the point
from which we started; and we have a history of our
primrose from its birth to the day when its leaves
and flowers wither away and it dies down for the
winter.

But what fairies are they which have been at work
here? First, the busy little fairy Life in the active
protoplasm; and secondly, the sun- waves. We have
seen that it was by the help of the sunbeams that the
green granules were made, and the water, carbonic
acid, and nitrogen worked up into the living plant.
And in doing, this work the sun- waves were caught
and their strength used up, so that they could no
longer quiver back into space. But are they gone for
ever? So long as the leaves or the stem or the root
of the plant remain they are gone, but when those are
destroyed we can get them back again. Take a hand-
ful of dry withered plants and light them with a match,
then as the leaves burn and are turned back again to
carbonic acid, nitrogen, and water, our sunbeams come
back again in the flame and heat.

And the life of the plant? What is it, and why is
this protoplasm always active and busy? I cannot
tell you. Study as we may, the life of the tiny plant
is as much a mystery as your life and mine. It came,
like all things, from the bosom of the Great Father,
but we cannot tell how it came nor what it is. We
can see the active grains moving under the microscope,
but we cannot see the power that moves them. We
only know it is a power given to the plant, as to you
and to me, to enable it to live its life, and to do its
useful work in the world.

iU!i«

174 THE FAIRY-LAND OF SCIENCF..

LECTURE Vm.

THE HISTORY OP A PIECE OF COAL.

HAVE here a piece of
coal (Fig. 47I. which,
though it has been cut
with some care so as to have a smooth face, is really
in no other way different from any ordinary lump

^ PIECE OF COAL.

175

which you can pick for yourself out of the coal-
scuttle. Our work to-day is to relate the history of
this black lump ; to learn what it is, what it has been,
and what it will be.

It looks uninteresting enough at first sight, and yet
if we examine it closely we shall find some questions

of coal, n, Smooth face, showing 1.

to ask even about its appearance. Look at the smooth
face of this specimen and see if you can explain those
fine lines which nm across so close together as to
look like the edges of the leaves of a book. Try to
break a piece of soft coal, and you will find that it will
split much more easily along those lines than across
the other way of the lump; and if you wish to light
a fire quickly you should always put this lined face
downward so that the heat can force its way up
through these cracks and gradually split up the
block. Then again if you break the coal carefully
along one of these lines you will find a fine film of
charcoal lying in the crack, and you will begin to sus-
pect that this black coal must have been built up

176 THE FAIRY'LAND OF SCIENCE.

in very thin layers, with a kind of black dust between
them.

The next thing you will call to mind is that this
coal bums and gives flame and heat, and that this
means that in some way sunbeams are imprisoned in
it; lastly, this will lead you to think of plants, and
how they work up the strength of the sunbeams into
their leaves, and hide black carbon in even the purest
and whitest substance they contain.

Is coal made of burned plants, then ? Not burned
ones, for if so it would not burn again; but you may
have read how the makers of charcoal take wood and
bake it without letting it burn, and then it turns black
and will afterward make a very good fire; and so
you will see that it is probable that our piece of
coal is made of plants which- have been baked and
altered, but which still have much sunbeam strength
bottled up in them, which can be set free as they
burn.

If you will take an imaginary journey with me to
a coal-pit you will see that we have very good evi-
dence that coal is made of plants, for in all coal-
mines we find remains of them at every step we
take.

Let us imagine that we have put on old clothes
which will not spoil, and have stepped into the iron
basket (see Fig. 48) called by the miners a cage, and
are being let down the shaft to the gallery where the
miners are at work. Most of them will probably be
in the gallery b, because a great deal of the coal in
a has been already taken out. But we will stop in a
because there we can see a great deal of the roof and

A PIECE OF COAL.

177

the floor. When we land on the floor of the gallery
we shall find ourselves in a kind of tunne! with railway
lines laid along it and trucks laden with coal coming
toward the cage to be drawn up, while empty ones
are running back to be loaded where the miners are
at work. Taking lamps in our hands and keeping
out of the way o£ the trucks, we will first throw the

Fig. 4B. — Imaginary si

light on the roof, which is made of shale or hardened
clay. We shall not have gone many yards before
we see impressions of plants in the shale, like those in
this specimen (Fig. 49), which was taken out of a coal-
mine at Neath in Glamorganshire in England. You
will recognise at once the marks of ferns {a), for they
look like those you gather in the hedges of an ordinary
country lane, and that long striped branch (b) does not
look unlike a reed, and indeed it is something of this
kind, as we shall see by-and-by. You will find plenty
of these impressions of plants as you go along the gal-

178 THE FAIRY-LAND OF SCIENCE.

Icry and look up at the roof, and with them there will j
be others with spotted stems, or with stems having- a 1
curious diamond pattern upon them, and many ferns I
of various kinds.

Next look down at your feet and examine the floor.

Fig. 4g. — A piece of shale wilh impi

You will not have to search long before you will al-1
most certainly find a piece of stone like that repre-

Fig. so.— St igm aria— root or unticrground slem uf Sigillac

sented in Fig. 50, which has also come from Neath. I
Colliery.* This fossil, which is the cast of a piece of al

ih indebted !
e fossils for n
ne for an earl

Williams, of Neath, fof
3 to Professor Judd focI

A PIECE OF COAL.

■' plant, puzzled those who found it for a very long time.

^ At last, however, Mr. Binney found the specimen

« growing to the bottom of the trunk of one of the fossil

■■ trees with spotted stems, called Sigillaria; and so

proved that this curious pitted stone is a piece of fossil

root, or rather underground stem, like that which we

found in the primrose, and that the little pits or

dents in it are scars where the rootlets once were

given off.

Whole masses of these root-stems, with ribbon-like
I roots lying scattered near them, are found buried in

the layer of clay called the underclay which makes the
floor of the coal, and they prove to us that this under-
clay must have been once the ground in which the
roots of the coal- plants grew. You will feel still more
sure of this when you find that there is not only one
; straight gallery of coal, but that galleries branch out

right and left, and that everywhere you find the coal
lying like a sandwich between the floor and the roof,
showing that quite a large piece of country must be
covered by these remains of plants all rooted in the
underclay.

But how about the coal itself? It seems likely,

' when we find roots below and leaves and stems above,

that the middle is made of plants, but can we prove

it? We shall see presently that it has been so crushed

. and altered by being buried deep in the ground that

\' the traces of leaves have almost been destroyed, though

I people who are used to examining with the miscro-

'• scope, can see the crushed remains of plants in thin

slices of coal.

But fortunately for us, perfect pieces of plants have
13

l8o THE FAIRY-LAND OF SCIENCE.

been preserved even in the coal-bed itself. Do you
remember our learning in Lecture IV that water
with lime in it petrifies things, that is, leaves car-
bonate of lime to fill up grain by grain the fibres
of an animal or plant as the living matter decays,
and so keeps an exact representation of the ob-
ject?

Now, it so happens that in a coal-bed at South
Ouram, near Halifax, in Canada, as well as in some
other places, carbonate of lime trickled in before the
plants were turned to coal, and made some round nod-
ules in the plant-bed, which look like cannon-balls.
Afterward, when all the rest of the bed was turned into
coal, these round balls remained crystallized, and by
cutting thin transparent slices across the nodule we
can distinctly see the leaves and stems and curious
little round bodies which make up the coal. Several
such sections may be seen at the British Museum, and
when we compare these fragments of plants with those
which we find above and below the coal-bed, we find
that they agree, thus proving that coal is made of
plants, and of those plants vhose roots grew in the
clay floor, while their heads reached up far above
where the roof now is.

The next question is, what kind of plants were
these? Have we anything like them living in the
world now? You might perhaps think that it would
be impossible to decide this question from mere petri-
fied pieces of plants. But many men have spent their
whole lives in deciphering all the fragments that could
be found, and though the section given in Fig. 51
may look to you quite incomprehensible, yet a botanist

^ PIECE OF COAL. jgi

can read it as we read a book. For example, at S
and L, where stems are cut across, he can learn ex-
actly how they were built up mside, and compare

G. 51.— ContenlB of a coal-ball. (Carnilhers.)* i'. Slem of
Sigillaria cul across, Z, Stem of Lepidodendron cut across.
Z', Stem of Lepidodendron cut lengthways. /, Cone of
Lepidodendron (Lepidostrobus) cut across. C, Stem of Cala-
mite cut across, c. c. c. Fruit of Calamite lengthways and
across. /, Stem of a fern with fraRmenls of fern-leaves
scattered round it. The small round dots scattered here
and there are the larger spores which have fallen out of the
fruit-cones.

•1 am much indeb
Museum, for allowing ir

ed to Mr. Carruihe
e to copy this figure

s, of ih

British
original

diagram of a coal-ball,

nd also for giving n

ne much

valuable

THE FAIRY-LAND OF SCIENCE.

tliL'iii with the Stems of living plants, while the fruits
c c and the little round spores lying near them, tell
him their history as well as if he had gathered them
from the tree. In this way we have learned to know
very fairly what the plants of the coal were like, and
you will be surprised

Lwhen I tell you that the
> huge trees of the coal-

- . . fc jW forests, of which we

sometimes find trunks
in the coal-mines from
ten to fifty feet long, are
only represented on the
earth now by small in-
significant plants, scarce-
ly ever more than two
feet, and often not many
inches high.
, Have you ever seen
the little club -moss
or Lye op odium which
grows in bogs, swamps,
and moist woods near-
ly all over the United States, from Lake Superior
to ^'irginia and Carolina, on heaths and mountains?
At the end of each of its branches it bears a cone made
of scaly leaves ; and fixed to the inside of each of these
leaves is a case called a sporangium, full of little spores
or moss-seeds, as we may call them, though they are
not exactly like true seeds. In one of these club-
mosses called Sclagiiiclla. the cases V. near the bottom
of the cone contain large spores b, while those near the

(i. 52. — S,-/a^'i/ii//,r sii.
Species of club-moss bearing

pSblic ubrarv

' I ,

'•. < I.

A PIECE OF COAL. 183

top, A, contain a powdery dust a. These spores are
full of resin, and they are collected on the Continent
for making artificial lightning in the theatres, because
they flare when lighted.

Now this little Selaginella is of all living plants the
one most like some of the gigantic trees of the coal-
forests. If you look at this picture of a coal-for-
est (Fig. 53), you will find it difficult perhaps to
believe that those great trees, with diamond mark-
ings all up the trunk, hanging over from the right
to the left of the picture, and covering all the top
with their boughs, could be in any way relations of
the little Selaginella; yet we find branches of them
in the beds above the coal, bearing cones larger
but just like Selaginella cones; and what is most
curious, the spores in these cones are exactly the
same kind and not any larger than those of the club-
moss.

These trees are called by botanists Lepidodendrons,
or scaly trees; there are numbers of them in all coal-
mines, and one trunk has been found 49 feet long.
Their branches were divided in a curious forked man-
ner and bore cones at the ends. The spores which
fell from these cones are found flattened in the coal,
and they may be seen scattered about in the coal-ball

(Fig. 51).

Another famous tree which grew in the coal-forests
was the one whose roots we found in the floor or
underclay of the coal. It has been called Sigillaria,
because it has marks like seals (sigilluniy a seal) all
up the trunk, due to the scars left by the leaves when
they fell from the tree. You will see the Sieillarias

i84

THE FAIRY-LAND OF SCIENCE.

on the left-hand side of the coal-forest picture, having

those curious tufts of leaves springing out of them at

the top. Their stems

make up a great deal of

the coal, and the bark

of their trunks is often

found in the clays above,

squeezed flat in lengths

of 30, 60, or 70 feet.

Sometimes, instead of

being flat the bark is

still in the shape of a

trunk, and the interior is

filled with sand; and

then the trunk is very

heavy, and if the miners

do not prop the roof up

well it falls down and

kills those beneath it.

Stigmaria (Fig. 50, page

178) is the root of the
Fig. 54. — Equisetum or horsetail. r~,. ... . 1 • r j

^ SigiUaria, and is found

in the clays below the coal. Botanists are not yet
quite certain about the seed-cases of this tree, but Mr.
Carruthers believes that they grew inside the base of
the leaves, as they do in the quillwort, a small plant
which grows at the bottom of mountain lakes in Eu-
rope and America.

But what is that curious reed-like stem we found
in the piece of shale (see Fig. 49) ? That stem is very
important, for it belonged to a plant called a Calamite,
which, as we shall see presently, helped to sift the

A PIECE OF COAL. 185

earth away from the coal and keep it pure. This plant
was a near relation of the '* horsetail," or Equisetum,
which grows in our marshes ; only, just as in the case
of the other trees, it was enormously larger, being
often 20 feet high, whereas the little Equisetum, Fig.
54, is seldom more than a foot, and never more than 6
feet high in North America, though in tropical South
America they are much higher. Still, if you have ever
gathered " horsetails,'' you will see at once that those
trees in the foreground of the picture (Fig. 53), with
leaves arranged in stars round the branches, are only
larger copies of the little marsh-plant; and the
seed-vessels of the two plants are almost exactly the
same.

These great trees, the Lepidodendrons, the Sigil-
larias, and the Calamites, together with large tree-
ferns and smaller ferns, are the chief plants that we
know of in the coal-forests. It seems very strange at
first that they should have been so large when their
descendants are now so small, but if you look at our
chief plants and trees now, you will find that nearly
all of them bear flowers, and this is a great advantage
to them, because it tempts the insects to bring them
the pollen-dust, as we saw in the last lecture.

Now the Lepidodendrons and their companions
had no true flowers, but only these seed-cases which
we have mentioned; but as there were no flowering
plants in their time, and they had the ground all to
themselves, they grew fine and large. By-and-by,
however, when the flowering plants came in, these be-
gan to crowd out the old giants of the coal-forests, so
that they dwindled and dwindled from century to cen-

1 86 THE FAIRY-LAND OF SCIENCE.

tury till their great-great-grandchildren, thousands of
generations after, only lift up their tiny heads in
marshes and on heaths, and tell us that they were big
once upon a time.

And indeed they must have been magnificent in
those olden days, when they grew thick and tall in
the lonely marches where plants and trees were the
chief inhabitants. We find no traces in the clay-beds
of the coal to lead us to suppose that men lived in
those days, nor lions, nor tigers, nor even birds to fly
among the trees; but these grand forests were almost
silent, except when a huge animal something like a
gigantic newt or frog went croaking through the
marsh, or a kind of grasshopper chirruped on the land.
But these forms of life were few and far between, com-
pared to the huge trees and tangled masses of ferns
and reeds which covered the whole ground, or were re-
flected in the bosom of the large pools and lakes round
about which they grew.

And now, if you have some idea of the plants and
trees of the coal, it is time to ask how these plants
became buried in the earth and made pure coal, in-
stead of decaying away and leaving behind only a
mixture of earth and leaves?

To answer this question, I must ask you to take
another journey with me to Norfolk in Virginia, be-
cause there we can see a state of things something
like the marshes of the coal-forests. All round about
Norfolk the land is low, flat, and marshy, and to the
south of the town, stretching far away into North
Carolina, is a large, desolate swamp, no less than forty

A PIECE OF COAL, 187

miles long and twenty-five broad. The whole place is
one enormous quagmire, overgrown with water-plants
and trees. The soil is as black as ink from the old,
dead leaves, grasses, roots, and stems which lie in it ;
and so soft, that everything would sink into it, if it
were not for the matted roots of the mosses, ferns,
and other plants which bind it together. You may
dig down for ten or fifteen feet, and find nothing
but peat made of the remains of plants which have
lived and died there in succession for ages and ages,
while the black trunks of the fallen trees lie here
and there, gradually being covered up by the dead
plants.

The whole place is so still, gloomy, and desolate,
that it goes by the name of the " Great Dismal
Swamp,'' and you see we have here what might well
be the beginning of a bed of coal; for we know that
peat when dried becomes firm and makes an excellent
fire, and that if it were pressed till it was hard and
solid it would not be unlike coal. If, then, we can
explain how this peaty bed has been kept pure from
earth, we shall be able to understand how a coal-bed
may have been formed, even though the plants and
trees which grow in this swamp are different from
those which grew in the coal-forests.

The explanation is not difficult; streams flow con-
stantly, or rather ooze into the Great Dismal Swamp
from the land that lies to the west, but instead of
bringing mud in with them as rivers bring to the sea,
they bring only clear, pure water, because, as they
filter for miles through the dense jungle of reeds,
ferns, and shrubs which grow round the marsh, all

1 88 THE FAIRY-LAND OF SCIENCE.

the earth is sifted out and left behind. In this way
the spongy mass of dead plants remains free from
earthy grains, while the water and the shade of the
thick forest of trees prevent the leaves, stems, etc.,
from being decomposed by the air and sun. And
so year after year as the plants die they leave their
remains for other plants to take root in, and the peaty
mass grows thicker and thicker, while tall cedar trees
and evergreens live and die in these vast, swampy for-
ests, and being in loose ground are easily blown down
by the wind, and leave their trunks to be covered up
by the growing moss and weeds.

Now we know that there were plenty of ferns and
of large Calamites growing thickly together in the
coal-forests, for we find their remains everywhere in
the clay, so we can easily picture to ourselves how the
dense jungle formed by these plants would fringe the
coal-swamp, as the present plants do the Great Dis-
mal Swamp, and would keep out all earthy matter, so
that year after year the plants would die and form
a thick bed of peat, afterward to become coal.

The next thing we have to account for is the bed
of shale or hardened clay covering over the coal. Now
we know that from time to time land has gone slowly
up and down on our globe so as in some places to
carry the dry ground under the sea, and in others to
raise the sea-bed above the water. Let us suppose,
then, that the Great Dismal Swamp was gradually to
sink down so that the sea washed over it and killed
the reeds and shrubs. Then the streams from the
west would not be sifted any longer but would bring
down mud, and leave it, as in the delta of the Nile or

A PIECE OF COAL, 189

Mississippi, to make a layer over the dead plants.
You will easily understand that this mud would have
niiny pieces of dead trees and plants in it, which were
stifled and died as it covered them over; and thus the
remains would be preserved like those which we find
now in the roof of the coal-galleries.

But still there are the thick sandstones in the coal-
mine to be explained. How did they come there?
To explain them, we must suppose that the ground
went on sinking till the sea covered the whole place
where once the swamp had been, and then sea-sand
would be thrown down over the clay and gradually
pressed down by the weight of new sand above, till it
formed solid sandstone and our coal-bed became buried
deeper and deeper in the earth.

At last, after long ages, when the thick mass of
sandstones above the bed b (Fig. 48, p. 177) had been
laid down, the sinking must have stopped and the land
have risen a little, so that the sea was driven back;
and then the rivers would bring down earth again and
make another clay-bed. Then a new forest would
spring up, the ferns, Calamites, Lepidodendrons, and
Sigillarias would gradually form another jungle, and
many hundreds of feet above the buried coal-bed 6, a
second bed of peat and vegetable matter would begin
to accumulate to form the coal-bed a.

Such is the history of how the coal which we now
dig out of the depths of the earth once grew as beauti-
ful plants on the surface. We cannot tell exactly all
the ground over which these forests grew, because
some of the coal they made has been carried away

igO ^^^ FAIRY^LAND OF SCIENCE.

since by rivers and cut down by the waves of the sea,
but we can say that wherever there is coal now, there
they must have been.

But what is it that has changed these beds of dead
plants into hard, stony coal? In the first place you
must remember they have been pressed down under
an enormous weight of rocks above them. We can
learn something about this even from our common
lead pencils. At one time the graphite or pure carbon,
of which the blacklead (as we wrongly call it) of our
pencils is made, was dug solid out of the earth. But
so much has now been used that they are obliged
to collect the graphite dust, and press it under a heavy
weight, and this makes such solid pieces that they can
cut them into leads for ordinary cedar pencils.

Now the pressure which we can exert by machinery
is absolutely nothing compared to the weight of all
those hundreds of feet of solid rock which lie over the
coal-beds, and which has pressed them down for thou-
sands and perhaps millions of years; and besides this,
we know that parts of the inside of the earth are very
hot, and many of the rocks in which coal is found are
altered by heat. So we can picture to ourselves that
the coal was not only squeezed into a solid mass, but
often much of the oil and gas which were in the leaves
of the plants was driven out by heat, and the whole
baked, as it were, into one substance. The difference
between coal which flames and coal which burns only
with a red heat, is chiefly that one has been baked
and crushed more than the other. Coal which flames
has still got in it the tar and the gas and the oils
which the plant stored up in its leaves, and these when

A PIECE OF COAL.

191

they escape again giwt back the sunbeams in a bright
flame. The hard stone coal, such as anthracite, on the
contrary, has lost a great part of these oilSj and only
carbon remains, which seizes hold of the oxygen of the
air and burns without flame. Coke is pure carbon,
which we make artificially by driving out the oils and
gases from coal, and the gas we burn is part of what
is driven out.

We can easily make coal-gas here in this room. I
have brought a tobacco-pipe, the bowl of which is
filled with a little powdered coal, and the broad end
cemented up with Stourbridge clay. When we place
this bowl over a spirit-lamp and make it very hot, the
gas is driven out at the narrow end of the pipe and
lights easily (see Fig. 55). This is the way all our gas

Fig. 55.

is made, only that furnaces are used to bake the coal
in, and the gas is passed into large reservoirs till it is
wanted for use.

You will find it difficult at first to understand how
coal can be so full of oil and tar and gases, until you
have tried to think over how much of all these there is

192 THE FAIRY-^LAND OF SCIENCE.

in plants, and especially in seeds — think of the oils of
almonds, of lavender, of cloves, and of caraways; and
the oils of turpentine which we get from the pines,
and out of which tar is made. When you remember
these and many more, and also how the seeds of the
club-moss now are largely charged with oil, you will
easily imagine that the large masses of coal-plants
which have been pressed together and broken and
crushed, would give out a great deal of oil which,
when made very hot, rises up as gas. You may often
yourself see tar oozing out of the lumps of soft coal
in a fire, and making little black bubbles which burst
and burn. It is from this tar that James Young first
made paraffin oil, and the spirit benzone comes from
the same source.

In the ages that have passed since the vegetation
that now forms our coal was deposited its slow decom-
position, perhaps under conditions of great heat and
pressure, has resulted in vast natural accumulations of
this coal-oil and also of coal-gas in the interior of the
earth.

The great storehouses that contain these valu-
able products of the ancient coal-forests are only to
be found where the bending of the strata makes gjeat
caverns. The rocks and earth above the rocks con-
stituting the domes over the great natural cisterns or
tanks often press, as may well be supposed, with enor-
mous weight upon the inclosed coal-oil or gas.

When these oil wells, as they are called, were first
discovered, and before any efficient means of restrain-
ing the flow had been contrived, the oil frequently
burst forth, and, carrying away the barriers erected

A PIECE OF COAL.

193

against it, overflowed the country, tainting; the air, be-
fouling the soil, and poisoning all the streams in its
neighbourhood.

,: ^ m-.

'.'^'.v

:#'^.t

i ^fiCj. ,

^^^

IG. 56. — Spouting oil well.

In the great Russian
field of Baku the flow of
coal-oil is still more diffi-
cult to control than in
our own country- The
heaviest derricks have
been swept away like
straws, well casings blown high in air, and the oil
in columns as thick as a man's body has spouted

194

THE FAIRY-LAND OF SCIENCE.

Up for days fully two hundred feet above the surface
of the earth, forming, as it flowed toward the sea, rivers
of oil many miles in length. The force of coal-gas es-
caping from the coal-gas wells in Indiana, Pennsyl-
vania, and Ohio, has been known to blow out drills of
nearly a ton in weight, and to burst the doubly-riveted
tanks and heavy iron mains which were used in at-
tempting to confine it, so that it was for a time thought
that nothing could be contrived that would withstand
its pressure. The roar of the escaping gas could be
heard for miles, and schools had to be closed and
all business suspended in the vicinity of the wells.
If the gas was set on fire, as sometimes happened,
the roaring was increased to such an extent that
workmen who were obliged to remain in its neigh-
bourhood were made deaf for life, and the light from
the well could in some cases be seen for forty miles
around.

Until the last few years, however, the very exist-
ence of most of these great reservoirs of potential en-
ergy was unsuspected, and although coal-oil skimmed
from the surface of pools in oil-bearing localities was
sometimes employed to a limited extent, mostly as a
medicine, it is only of late years it has been found in
quantities sufficient to allow its extended use. Yet so
rapid has its applications to uncounted domestic, me-
chanical, and industrial purposes advanced that it may
already justly claim to materially modify our progress
in the arts and sciences.

Not only is mineral oil now used to cook our
food, to light our houses, and to drive our engines, but
the manufacture of a great number of articles and of

PIECE OF COAL.

195

widely used substances, such as glass and iron, lias
not only been greatly improved, but made much
cheaper by its use.

From benzone, again, we get a liquid called aniline,
from which are made so many of our beautiful dyes
■ — mauve, magenta, and violet; and what is still more
curious, the bitter almonds, pear-drops, and many
other candies which children like so well, are actually
flavoured by essences which come out of coal-tar, and

Fig. 57.

sugar itself is many times less sweet than saccharine,
which has the same origin. Thus from coal we get not
only nearly all our heat and our iight, but beautiful
colours, sweets, and pleasant flavours. We spoke just
now of the plants of the coal as being without beautiful
flowers, and yet we see that long, long after their death
they give us lovely colours and tints as beautiful as any
in flower- wo rid now.

196

THE FAIRY-LAND OF SCIENCE.

But without doubt what promises to be the most
important as well as the most useful product of coal-tar
is albumen, which Professor Lilienfeld has succeeded
in obtaining from it. Albumen, with starchy, sugary,
and acid substances, constitutes the basis of both ani-
mal and vegetable foods. An ounce of pure albumen
has twenty times the nourishing power of the same
weight of meat. It will nearly equal in this respect
a peck of potatoes, besides having the quality of not
interfering with digestion even though eaten exclu-
sively for months at a time.

Wonderful as it may appear to us that nauseous,
black, ill-smelling coal-tar can be made to yield de-
licious and delicate essences, such as caflFein, which is
the essential principle of tea and coffee, artificial vanil-
lin, exactly equivalent to the crystallized product of
the vanilla bean, and the essence of bitter almonds,
yet when we find that it can also be transformed into
the most wholesome and nutritious of palatable food,
this seems little short of miraculous, and to call for
the exercise of a power fully as wonderful as any as-
cribed to magician or fairy, almost in appearance as
great as that which could turn stones into bread.

Think, then, how much we owe to these plants
which lived and died so long ago! If they had been
able to reason, perhaps they might have said that
they did not seem of much use in the world. They
had no pretty flowers, and there was no one to ad-
mire their beautiful green foliage except a few croak-
ing reptiles, and little crickets and grasshoppers; and
they lived and died all on one spot, generation after

A PIECE OF COAL. 197

generation, without seeming to do much good to any-
thing or anybody. Then they were covered up and
put out of sight, and down in the dark earth they
were pressed all out of shape and lost their beauty
and became only black, hard coal. There they
lay for centuries and centuries, and thousands and
thousands of years, and still no one seemed to want
them.

At last, one day, long, long after man had been
living on the earth, and had been burning wood for
fires, and so gradually using up the trees in the forests,
it was discovered that this black stone would burn,
and from that time coal has been becoming every day
more and more useful. Without it not only should
we have been without warmth in our houses, or light
in our streets when the stock of forest-wood was used
up; but we could never have melted large quantities
of iron-stone and extracted iron. We have proof of
this in the county of Sussex, in England. The whole
country is full of ironstone. Iron-foundries were at
work there as long as there was wood enough to sup-
ply them, but gradually the works fell into disuse, and
the last furnace was put out in the year 1809. So
now, because there is no coal in Sussex, the iron
lies idle; while in the North, where the ironstone is
near the coal-mines, hundreds of tons are melted out
every day.

Again, without coal we could have had no engines
of any kind, and consequently no large manufactories
of cotton goods, linen goods, or cutlery. In fact, al-
most everything we use could only have been made
with difficulty and in small quantities; and even if we

• ,1

■ ■ i
I

i
I

198 THE FAIRY-LAND OF SCIENCE.

could have made them it would have been impossible
to have sent them so quickly all over the world with-
out coal, for we could have had no railways or steam-
ships, but must have carried all goods along canals,
and by slow sailing vessels. We ourselves must have
taken days to perform journeys now made in a few-
hours, and months to reach other countries across
the sea.

In consequence of this we should have remained a
very poor people. Without manufactories and indus-
tries we should have had to live chiefly by tilling the
ground, and everyone being obliged to toil for their
daily bread, there would have been much less time
or opportunity for anyone to study science, or litera-
ture, or history, or to provide themselves with com-
forts and refinements of life.

All this then, those plants and trees of the far-off
ages, which seemed to lead such useless lives, have
done and are doing for us. There are many people
in the world who complain that life is dull, that they
do not see the use of it, and that there seems no work
specially for them to do. I would advise such people,
whether they are grown up or little children, to read
the story of the plants which form the coal. These
saw no results during their own short existences, they
only lived and enjoyed the bright sunshine, and did
their work, and were content. And now thousands,
probably millions, of years after they lived and died,
civilization owes her progress, and we much of our
happiness and comfort, to the sunbeams which those
plants wove into their lives.

They burst forth again in our fires, in our brilliant

A PIECE OF COAL. 199

lights, and in our engines, and do the greater part of
our work; teaching us

" That nothing walks with aimless feet,
That not one life shall be destroyed,
Or cast as rubbish to the void,
When God hath made the pile complete."

— In Memoriam, liv.

200 ^-^-^ FAIRV-LAND OF SCIENCE.

LECTURE IX.

BEES IN THE HIVE.

I AM going to ask you to visit with me to-day one
of the most wonderful cities in the world. It is a
city with no human beings in it, and yet it is densely

BEES IN THE HIVE. 20I

populated, for such a city may contain from twenty
thousand to sixty thousand inhabitants. In it you
will find streets, but no pavements, for the inhabitants
walk along the walls of the houses; while in the
houses you will see no windows, for each house just
fits its owner, and the door is the only opening in
it. Though made without hands these houses are
most evenly and regularly built in tiers one above the
other; and here and there a few royal palaces, larger
and more spacious than the rest, catch the eye con-
spicuously as they stand out at the corners of the
streets.

Some of the ordinary houses are used to live in,
while others serve as storehouses where food is laid up
in the summer to feed the inhabitants during the
winter, when they are not allowed to go outside the
walls. Not that the gates are ever shut: that is not
necessary, for in this wonderful city each citizen fol-
lows the laws ; going out when it is time to go out,
coming home at proper hours, and staying at home
when it is his or her duty. And in the winter, when
it is very cold outside, the inhabitants, having no fires,
keep themselves warm within the city by clustering
together, and never venturing out of doors.

One single queen reigns over the whole of this
numerous population, and you might perhaps fancy
that, having so many subjects to work for her and
w^ait upon her, she would do nothing but amuse her-
self. On the contrary, she too obeys the laws laid
down for her guidance, and never, except on one or
two state occasions, goes out of the city, but works as
hard as the rest in performing her own royal duties.

202 THE FAIRY-LAND OF SCIENCE.

From sunrise to sunset, whenever the weather is
fine, all is life, activity, and bustle in this busy city.
Though the gates are so narrow that two inhabitants
can only just pass each other on their way through
them, yet thousands go in and out every hour of the
day ; some bringing in materials to build new houses,
others food and provisions to store up for the winter ;
and while all appears confusion and disorder among
this rapidly moving throng, yet in reality each has her
own work to do, and perfect order reigns over the
whole.

Even if you did not already know from the title of
the lecture what city this is that I am describing, you
would no doubt guess that it is a beehive. For where
in the whole world, except indeed upon an ant-hill, can
we find so busy, so industrious, or so orderly a com-
munity as among the bees? More than a hundred
years ago, a blind naturalist, Francois Huber, set him-
self to study the habits of these wonderful insects,
and with the help of his wife and an intelligent man-
servant managed to learn most of their secrets. Before
his time all naturalists had failed in watching bees,
because if they put them in hives with glass windows,
the bees, not liking the light, closed up the windows
with cement before they began to work. But Huber
invented a hive which he could open and close at will,
putting a glass hive inside it, and by this means he
was able to surprise the bees at their work. Thanks
to his studies, and to those of other naturalists who
have followed in his steps, we now know almost as
much about the home of bees as we do about our own ;
and if we follow out to-day the building of a bee city

BEES IN THE HIVE.

203

and the life of its inhabitants, I think you will ac-
knowledge that they are a wonderful community, and
that it is a great compliment to anyone to say that he
or she is *'as busy as a bee/'

In order to begin at the beginning of the story,
let us suppose that we go into a country garden
one fine morning in May when the sun is shining
brightly overhead, and that we see hanging from the
bough of an old apple-tree a black object which looks
very much like a large plum-pudding. On approach-
ing it, however, we see that it is a large cluster or
swarm of bees clinging to each other by their legs;
each bee with its two fore-legs clinging to the two
hinder legs of the one above it. In this way as many
as 20,000 bees may be clinging together, and yet they
hang so freely that a bee, even from quite the centre
of the swarm, can disengage herself from her neigh-
bours and pass through to the outside of the cluster
whenever she wishes.

If these bees were left to themselves, they would
find a home after a time in a hollow tree, or under
the roof of a house, or in some other cavity, and begin
to build their honeycomb there. But as we do not
wish to lose their honey we will bring a hive, and,
holding it under the swarm, shake the bough gently
so that the bees fall into it, and cling to the sides
as we turn it over on a piece of clean linen, on the
stand where the hive is to be.

And now let us suppose that we are able to watch
what is going on in the hive. Before five minutes
are over the industrious little insects have begun to

^V 204 Tf'E FAIRY-LAND OF SCIENCE.

^r disperse and to make arrangements in their new home
A number (perhaps about two thousand) of large,
lumbering bees of a darker colour than the rest, will,
it is true, wander aimlessly about the hive, and wait
for the others to feed them and house them ; but these
are the drones, or male bees (3, Fig. 58), who never
do any work except during one or two days in their
whole lives. But the smaller working bees (i. Fig. 58!
begin to be busy at once. Some fly off in search of

FRi.;S.—i. Worker bc-c. 2. Quttii-ljtf. 3, Dmne or male bee.
honey. Others walk carefully all round the inside of
the hive to see if there are any cracks in it ; and if
there are. they go off to the horse-chestnut trees,
poplars, hollyhocks, or other plants which have sticky
buds, and gather a kind of gum called " propolis,"
with which they cement the cracks and make them
air-tight. Others again, cluster round one bee (2, Fig.
58) blacker than the rest and having a longer body

BEES IN THE HIVE.

205

and shorter wings ; for this is the queen-bee, the moth-
er of the hive, and she must be watched and tended.

But the largest number begin to hang in a cluster
from the roof just as they did from the bough of the
apple-tree. What are they doing there ? Watch for a
little while and you will soon see one bee come out
from among its companions and settle on the top of
the inside of the hive, turning herself round and round,
so as to push the other bees back, and to make a space
in which she can work. Then she will begin to pick
at the under part of her body with her fore-legs, and
will bring a scale of wax from a curious sort of pocket
under her abdomen. Holding this wax in her claws,
she will bite it with her hard, pointed upper jaws,
which move to and fro sideways like a pair of pincers,
then, moistening it with her tongue into a kind of
paste, she will draw it out like a ribbon and plaster it
on the top of the hive.

After that she will take another piece ; for she has
eight of these little wax-pockets, and she will go on
till they are all exhausted. Then she will fly away
out of the hive, leaving a small wax lump on the hive
ceiling or on the bar stretched across it ; then her place
will be taken by another bee who will go through
the same manoeuvres. This bee will be followed bv
another, and another, till a large wall of wax has
been built, hanging from the bar of the hive as in

^i&- 59» o"ly that it will not yet have cells fashioned
in it.

Meanwhile the bees which have been gathering

honey out of doors begin to come back laden. But

they cannot store their honey, for there are no cells

THE FAIRY-LAND OF SCIENCE.

made yet to put it in ; neither can they build combs
with tlie rest, for they have no wax in their wax-
pockets. So they just go and hang quietly on to the
other bees, and there they remain for twenty-four
hours, during which time they digest the honey they
have gathered, and part of
it forms wax and oozes
out from the scales under
their body. Then they
are prepared to join the
others at work and plaster
wax on to the hive.

And now, as soon as a

rough lump of wax is

ready, another set of bees

Fig. 59.— Plate of wax wilh bases come to do their work.

of cells, hanging from the These are called the nurs-

bar of a hive. ■ i l >l

i«^ bees, because they pre-
pare the cells and feed the young ones. One of these
bees, standing on the roof of the hive, begins to force
her head into the wax, biting with ber jaws and moving
her head to and fro. Soon she has made the begin-
ning of a round hollow, and then she passes on to
make another, while a second bee takes her place and
enlarges the first one. As many as twenty bees will
be employed in this way, one after another, upon each
hole before it is large enough for the base of a cell.

Meanwhile another set of nursing bees have been
working just in the same way on the other side of the
wax, and so a series of hollows are made back to back
all over the comb. Then the bees form the walls of
the cells, and soon a number of six-sided tubes, about

BEES IN THE HIVE.

207

half an inch deep, stand all along each side of the
comb ready to receive honey or bee-eggs.

You can see the shape of these cells in c, rf, Fig. 60,
and notice how closely they fit into each other. Even
the ends are so shaped that, as they lie back to back,
the bottom of one cell (b, Fig. 60) fits into the space
between the ends of three cells meeting it from the
opposite side (a. Fig. 60), while they fit into the spaces
around it. Upon this plan the clever little bees fill
every atom of space, use the least possible quantity of

Fig. 60. — B shows in the centre the closed end of a cell which
would fit into the space in the centre of the three closed
cells in A, while the ends of these three would fit into the
spaces in B. r, d^ side-view of cells.

wax, and make the cells lie so closely together that
the whole comb is kept warm when the young bees
are in it.

There are some kinds of bees who do not live in
hives, but each one builds a home of its own. These
bees — such as the upholsterer bee, which digs a hole in
the earth and lines it with flowers and leaves, and the
mason bee, which builds in walls — do not make six-
sided cells, but round ones, for room is no object to
them. But nature has gradually taught the little hive-
bee to build its cells more and more closely, till they

2o8 THE FAIRY-LAND OF SCIENCE.

fit perfectly within each other. If you make a number
of round holes close together in a soft substance, and
then squeeze the substance evenly from all sides, the
rounds will gradually take a six-sided form, showing
that this is the closest shape into which they can be
compressed. Although the bee does not know this,
yet as she gnaws away every bit of wax that can be
spared she brings the holes into this shape.

As soon as one comb is finished, the bees begin
another by the side of it, leaving a narrow lane be-
tween, just broad enough for two bees to pass back to
back as they crawl along, and so the work goes on
till the hive is full of combs.

As soon, however, as a length of about five or six
inches of the first comb has been made into cells,
the bees which are bringing home honey no longer
hang to make it into wax, but begin to store it in the
cells. We all know where the bees go to fetch their
honey, and how, when a bee settles on a flower, she
thrusts into it her small tongue-like proboscis, which
is really a lengthened under-lip, and sucks out the
drop of honey. This she swallows, passing it down
her throat into a honey-bag or first stomach, which
lies between her throat and her real stomach, and
when she gets back to the hive she can empty this bag
and pass the honey back through her mouth again
into the honey-cells.

But if you watch bees carefully, especially in the
spring-time, you will find that they carry off something
else besides honey. Early in the morning, when the
dew is on the ground, or later in the day, in moist,
shady places, you may see a bee rubbing itself against

BEES IN THE HIVE.

209

a flower, or biting those bags of yellow dust or pollen
which we mentioned in Lecture VII. When she has
covered herself with pollen, she will brush it off with
her feet, and, bringing it to her mouth, she will moist-
en and roll it into a little ball, and then pass it back
from the first pair of legs to the second and so to the
third or hinder pair. Here she will pack it into a
little hairy groove called a " basket " in the joint of
one of the hind legs, where you may see it, looking
like a swelled joint, as she hovers among the flowers.
She often fills both hind legs in this way, and when
she arrives back at the hive the nursing bees take the
lumps from her, and eat it themselves, or mix it with
honey to feed the young bees; or, when they have
any to spare, store it away in old honey-cells to be
used by-and-by. This is the dark, bitter stuff called
" bee-bread '' which you often find in a honeycomb,
especially in a comb which has been filled late in the
summer.

When the bee has been relieved of the bee-bread
she goes off to one of the clean cells in the new comb,
and, standing on the edge, throws up the honey from
the honey-bag into the cell. One cell will hold the
contents of many honey-bags, and so the busy little
workers have to work all day filHng cell after cell, in
which the honey lies uncovered, being too thick and
sticky to flow out, and is used for daily food — unless
there is any to spare, and then they close up the cells
with wax to keep for the winter.

Meanwhile, a day or two after the bees have settled
in the hive, the queen-bee begins to get ven'
15

2IO THE FAIRY-LAND OF SCIENCE,

She goes outside the hive and hovers about a little
while, and then comes in again, and though generally
the bees all look very closely after her to keep her
indoors, yet now they let her do as she likes. Again
she goes out, and again back, and then, at last, she
soars up into the air and flies away. But she is not
allowed to go alone. All the drones of the hive rise
up after her, forming a guard of honour to follow her
wherever she goes.

In about half-an-hour she comes back again, and
then the working bees all gather round her, knowing
that now she will remain quietly in the hive and
spend all her time in laying eggs : for it is the queen-
bee who lays all the eggs in the hive. This she
begins to do about two days after her flight. There
are now many cells ready besides those filled with
honey: and, escorted by several bees, the queen-bee
goes to one of these, and, putting her head into it,
remains there a second as if she were examining
whether it would make a good home for the young
bee. Then, coming out, she turns round and lays a
small, oval, bluish-white q^%^ in the cell. After this
she takes no more notice of it, but goes on to the next
cell and the next, doing the same thing, and laying
eggs in all the empty cells equally on both sides of
the comb. She goes on so quickly that she some-
times lays as many as 200 eggs in one day.

Then the work of the nursing bees begins. In two
or three days each ^^^ has become a tiny maggot or
larva, and the nursing bees put into its cell a mixture
of pollen and honey which they have prepared in their
own mouths, thus making a kind of sweet bath in

BEES IN THE HIVE, 21I

which the larva lies. In five or six days the larva
grows so fat upon this that it nearly fills the cell, and
then the bees seal up the mouth of the cell with a thin
cover of wax, made of little rings and with a tiny hole
in the centre.

As soon as the larva is covered in, it begins to give*
out from its under-lip a whitish, silken film, made of
two threads of silk glued together, and with this it
spins a covering or cocoon all round itself, and so it
remains for about ten days more. At last, just twenty-
one days after the ^^'g was laid, the young bee is quite
perfect, lying in the cell as in Fig. 61, and she begins
to eat her way through the cocoon and through the
waxen lid, and scrambles out of her cell. Then the
nurses come again to her, stroke her wings and feed
her for twenty-four hours, and after that she is quite
ready to begin work, and flies out to gather honey
and pollen like the rest of the workers.

By this time the number of working bees in the
hive is becoming very great, and the storing of honey
and pollen-dust goes on very quickly. Even the empty
cells which the young bees have left are cleaned out
by the nurses and filled with honey ; and this honey is
darker than that stored in clean cells, and which we
always call " virgin honey '' because it is so pure and
clear.

At last, after six weeks, the queen leaves off laying
worker-eggs, and begins to lay, in some rather larger
cells, eggs from which drones, or male bees, will grow
up in about twenty days. Meanwhile the worker-bees
have been building on the edge of the cones some
very curious cells (^, Fig. 61) which look like t^*

THE FAIRY-LAND OF SCIENCE.

hanging with the open side upward, and about every
three days the queen stops in laying drone-eggs and
goes to put an egg in one of these cells. Notice that
she waits three days between each of these peculiar
layings, because we shall see
presently that there is a good
reason for her doing so.

The nursing bees take
great care of these eggs, and
instead of putting ordinary
food into the cell, they fill
it with a sweet, pungent jelly,
for the larva is to become a
princess and a future queen -
bee. Curiously enough, it
seems to be the peculiar food
and the size of the cell which
makes the larva grow into a
mother-bee which can lay
eggs, for if a hive has the
misfortune to lose its queen,
they take one of the ordi-
nary worker-larvae and put it
into a royal cell and feed it
terward to become bees, ^ith jelly, and it becomes a
?, aroya ce . queen-bee. As soon as the

princess is shut in like the others, she begins to spin
her cocoon, but she does not quite close it as the other
bees do, but leaves a hole at the top.

At the end of sixteen days after the first royal
egg was laid, the eldest princess begins to try to eat
her way out of her cell, and about this time the old

li. (n. — Brood-con
open, with the pupse,
or young bees,/,/, ii
the cells. The lowe

BEES IN THE HIVE.

213

queen becomes very uneasy, and wanders about dis-
tractedly. The reason of this is, that there can never
be two queen-bees in one hive, and the queen knows
that her daughter will soon be coming out of her
cradle and will try to turn her off her throne. So,
not wishing to have to fight for her kingdom, she
makes up her mind to seek a new home and take a
number of her subjects with her. If you watch the
hive about this time you will notice many of the bees
clustering together after they have brought in their
honey, and hanging patiently, in order to have plenty
of wax ready to use when they start, while the queen
keeps a sharp look-out for a bright, sunny day, on
which they can swarm : for bees will never swarm on
a wet or doubtful day if they can possibly help it, and
we can easily understand why, when we consider how
the rain would clog their wings and spoil the wax
under their bodies.

Meanwhile the young princess grows very impa-
tient, and tries to get out of her cell, but the worker-
bees drive her back, for they know there would be a
terrible fight if the two queens met. So they close
up the hole she has made wtth fresh wax after having
put in some food for her to live upon till she is re-
leased.

At last a suitable day arrives, and about ten or
eleven o'clock in the morning the old queen leaves the
hive, taking with her about 2000 drones and from
12,000 to 20,000 worker-bees, which fly a little way
clustering round her till she alights on the bough of
some tree, and then they form a compact swarm ready
for a new hive or to find a home nf flt#»ir own.

214

THE FAIRY-LAND OF SCIENCE.

Leaving them to go their way, we will now return
to the old hive. Here the liberated princess is reign-
ing in all her glory; the worker-bees crowd round
her, watch over her, and feed her as though they
could not do enough to show her honour. But still
she is not happy. She is restless, and runs about
as if looking for an enemy, and she tries to get at the
remaining royal cells where the other young princesses
are still shut in. But the workers will not let her
touch them, and at last she stands still and begins to
beat the air with her wings and to tremble all over,
moving more and more quickly, till she makes quite a
loud, piping noise.

Hark ! What is that note answering her ? It is a
low, hoarse sound, and it comes from the cell of the
next eldest princess. Now we see why the young
queen has been so restless. She knows her sister will
soon come out, and the louder and stronger the sound
becomes within the cell, the sooner she knows the
fight will have to begin. And so she makes up her
mind to follow her mother's example and to lead oflf
a second swarm. But she cannot always stop to
choose a fine day, for her sister is growing very strong
and may come out of her cell before she is off. And
so the second, or aftcr-swarm, gets ready and goes
away. And this explains why princesses' eggs are
laid a few days apart, for if they were laid all on the
same day, there would be no time for one princess to
go off with a swarm before the other came out of her
cell. Sometimes, when the workers are not watchful
enough, two queens do meet, and then they fight till
one is killed ; or sometimes they both go off with the

BEES IN THE HIVE.

215

same swarm without finding each other out. But this
only delays the fight till they get into the new hive;
sooner or later one must be killed.

And now a third queen begins to reign in the old
hive, and she is just as restless as the preceding ones,
for there are still more princesses to be born. But
this time, if no new swarm wants to start, the workers
do not try to protect the royal cells. The young
queen darts at the first she sees, gnaws a hole with
her jaws, and, thrusting in her sting through the hole
in the cocoon, kills the young bee while it is still a
prisoner. She then goes to the next, and the next,
and never rests till all the young princesses are de-
stroyed. Then she is contented, for she knows no
other queen will come to dethrone her. After a few
days she takes her flight in the air with the drones, and
comes home to settle down in the hive for the winter.

Then a very curious scene takes place. The drones
are no more use, for the queen will not fly out again,
and these idle bees will never do any work in the
hive. So the worker-bees begin to kill them, falling
upon them, and stinging them to death, and as the
drones have no stings they cannot defend themselves,
and in a few days there is not a drone, nor even a
drone-egg, left in the hive. This massacre seems very
sad to us, since the poor drones have never done any
harm beyond being hopelessly idle. But it is less sad
when we know that they could not live many weeks,
even if they were not attacked, and, with winter com-
ing, the bees cannot aflFord to feed useless mouths,
so a quick death is probably happier for them than
starvation.

.'■i

2i6 T^^ FAIRY-LAND OF SCIENCE.

And now all the remaining inhabitants, of the hive
settle down to feeding the young bees and laying in
the winter's store. It is at this time, after they have
been toiling and saving, that we come and take their
honey; and from a well-stocked hive we may even
take 30 lbs. without starving the industrious little in-
habitants. But then we must often feed them in re-
turn, and give them sweet syrup in the late autumn
and the next early spring when they cannot find any
flowers.

Although the hive has now become comparatively
quiet and the work goes on without excitement, yet
every single bee is employed in some way, either out
of doors or about the hive. Besides the honey col-
lectors and the nurses, a certain number of bees are
told off to ventilate the hive. You will easily under-
stand that where so many insects are packed closely
together the heat will become very great, and the air
impure and unwholesome. And the bees have no
windows that they can open to let in fresh air, so they
are obliged to fan it in from the one opening of the
hive. The way in which they do this is very interest-
ing. Some of the bees stand close to the entrance,
with their faces toward it, and opening their wings,
so as to make them into fans, they wave them to and
fro, producing a current of air. Behind these bees,
and all over the floor of the hive, there stand others,
this time with their backs toward the entrance, and
fan in the same manner, and in this way air is sent into
all the passages.

Another set of bees clean out the cells after the
young bees are born, and make them fit to receive

BEES IN THE HIVE.

217

honey, while others guard the entrance of the hive to
keep away the destructive wax-moth, which tries to
lay its eggs in the comb so that its young ones may
feed on the honey. All industrious people have to
guard their property against thieves and vagabonds,
and the bees have many intruders, such as wasps and
snails and slugs, which creep in whenever they get
a chance. If they succeed in escaping the sentinel
bees, then a fight takes place within the hive, and the
invader is stung to death.

Sometimes, however, after they have killed the
enemy, the bees cannot get rid of his body, for a snail
or slug is too heavy to be easily moved, and yet it
would make the hive very unhealthy to allow it to
remain. In this dilemma the ingenious little bees
fetch the gummy " propolis '' from the plant-buds and
cement the intruder all over, thus embalming his body
and preventing it from decaying.

And so the life of this wonderful city goes on.
Building, harvesting, storing, nursing, ventilating and
cleaning from morn till night, the little worker-bee
lives for about eight months, and in that time has
done quite her share of work in the world. Only the
young bees, born late in the season, live on till the
next year to work in the spring. The queen-bee lives
longer, probably about two years, and then she too
dies, after having had a family of many thousands of
children.

We have already pointed out that in our fairy-land
of nature all things work together so as to bring order
out of apparent confusion. But though we should
naturally expect winds and currents, rivers and clonHs.

2l8 THE FAIRY-LAND OF SCIENCE.

and even plants to follow fixed laws, we should
scarcely have looked for such regularity in the life
of the active, independent busy bee. Yet we see that
she, too, has her own appointed work to do, and does
it regularly and in an orderly manner. In this lecture
we have been speaking entirely of the bee within the
hive, and noticing how marvellously her instincts
guide her in her daily life. But within the last few
years we have learned that she performs a most curi-
ous and wonderful work in the world outside her
home, and that we owe to her not only the sweet
honey we eat, but even in a great degree the beauty
and gay colours of the flowers which she visits when
collecting it. This work will form the subject of our
next lecture, and while we love the little bee for her
constant industry, patience, and order within the hive,
we shall, I think, marvel at the wonderful law of na-
ture which guides her in her unconscious mission of
love among the flowers which grow around it.

BEES AND FLOWERS.

219 ■

LECTURE * X.

BEES AXD FLOWERS.

-=^^^^^

LS^t^HB^

^^wlS^£

\A/HATEVER thouf^lns ^^'rJhHP^'
>'* each one of you may l^^m

^ ■

have brought to the lecture

to-day, I want you to throw them all aside an

1 fancy 1

_ yourself to be in a pretty country garden on a hot ■
^h summer's morning. Perhaps you have been walking, ^|

220 ^^^ FAIRY-LAKD OF SCIENCE.

or reading, or placing, but it is getting too hot now to
do annhing; and so you have chosen the shadiest
nook under the old walnut-tree, close to the flower-
bed, on the lawn, and would almost like to go to sleep
if it were not too early in the day.

As you lie there thinking of nothing in particular,
except how pleasant it is to be idle now and then,
you notice a gentle buzzing close to you, and you see
that on the flower-bed close by several bees are work-
ing busily among the flowers. They do not seem to
mind the heat, nor to wish to rest; and they fly so
lightly and look so happy over their work that it does
not tire vou to look at them.

That great humble-bee takes it leisurely enough as
she goes lumbering along, poking her head into the
larkspurs, and remaining so long in each you might
almost think she had fallen asleep. The brown hive-
bee, on the other hand, moves busily and quickly
among the stocks, sweet peas, and mignonette. She
is evidently out on active duty, and means to get all
she can from each flower, so as to carry a good load
back to the hive. In some blossoms she does not stav
a moment, but draws her head back directly she has
popped it in, as if to say, " No honey there." 'But
over the full blossoms she lingers a little, and then
scrambles out again with her drop of honey, and goes
off to seek more in the next flower.

Let us watch her a little more closely. There are
plenty of different plants growing in the flower-bed,
but, curiously enough, she does not go first to one
kind and then to another; but keeps to one, perhaps
the mignonette, the whole time, till she flies away.

BEES AND FLOWERS. 221

Rouse yourself up to follow her, and you will see she
takes her way back to the hive. She may perhaps
stop to visit a stray plant of mignonette on her way,
but no other flower will tempt her till she has taken
her load home.

Then when she comes back again she may perhaps
go to another kind of flower, such as the sweet peas,
for instance, and keep to them during the next jour-
ney, but it is more likely that she will be true to her
old friend the mignonette for the whole day.

We all know why she makes so many journeys
between the garden and the hive, and that she is
collecting drops of honey from each flower, and car-
rying it to be stored up in the honeycomb for winter^s
food. How she stores it, and how she also gathers
pollen-dust for her bee-bread, we saw in the last lec-
ture; to-day we will follow her in her work among
the flowers, and see, while they are so useful to her,
what she is doing for them in return.

We have already learned from the life of a prim-
rose that plants can make better and stronger seeds
when they can get pollen-dust from another plant, than
when they are obliged to use that which grows in the
same flower; but I am sure you will be very much
surprised to hear that the more we study flowers the
more we find that their colours, their scent, and their
curious shapes are all so many baits and traps set by
nature to entice insects to come to the flowers, and
carry this pollen-dust from one to the other.

So far as we know, it is entirely for this purpose
that the plants form honey in different parts of the
flower, sometimes in little * nds, as in the

222 THE FAIRY-LAXD OF SCIENCE.

petals of the buttercup flower, sometimes in clear
drops, as in the tube of the honeysuckle. This food
they prepare for the insects, and then they have all
sorts of contrivances to entice them to come and
fetch it.

You will remember that the plants of the coal had
no bright or conspicuous flowers. Now we can under-
stand why this was, for there were no flying insects
at that time to carry the pollen-dust from flower to
flower, and therefore there was no need of coloured
flowers to attract them. But little by little, as flies,
butterflies, moths, and bees began to live in the world,
flowers too began to appear, and plants hung out these
gay-coloured signs, as much as to say, " Come to me,
and I will give you honey if you will bring me pollen-
dust in exchange, so that my seeds may grow healthy
and strong.'*

We cannot stop to inquire to-day how this all
gradually came about, and how the flowers gradually
put on gay colours and curious shapes to tempt the
insects to visit them ; but we will learn something
about the way they attract them now, and how you
may see it for yourselves if you keep your eyes
open.

For example, if you watch the different kinds of
grasses, sedges, and rushes, which have such tiny
flowers that you can scarcely see them, you will find
that no insects visit them. Neither will you ever find
bees buzzing round oak-trees, nut-trees, willows, elms,
or birches. But on the pretty and sweet-smelling
apples-blossoms, or the strongly scented lime-trees,
you will find bees, wasps, and plenty of other insects.

BEES AND FLOWERS.

223

The reason of this is that grasses, sedges, rushes,
nut-trees, willows, and the others we have mentioned,
have all of them a great deal of pollen-dust, and as
the wind blows them to and fro, it wafts the dust from
one flower to another, and so these plants do not want
the insects, and it is not worth their while to give out
honey, or to have gaudy or sweet-scented flowers to
attract them.

But wherever you see bright or conspicuous flow-
ers you may be quite sure that the plants want the bees
or some other winged insect to come and carry their
pollen for them. Snowdrops hanging their white
heads among their green leaves, crocuses with their
violet and yellow flowers, the gaudy poppy, the large-
flowered hollyhock or the sunflower, the flaunting
dandelion, the pretty pink willow-herb, the clustered
blossoms of the mustard and turnip flowers, the bright
blue forget-me-not and the delicate little yellow tre-
foil, all these are visited by insects, which easily catch
sight of them as they pass by and hasten to sip their
honey.

Sir John Lubbock has shown that bees are not only
attracted by bright colours, but that they even know
one colour from another. He put some honey on slips
of glass with coloured papers under them, and when
he had accustomed the bees to find the honev al-
ways on the blue glass, he washed this glass clean,
and put the honey on the red glass instead. Now if
the bees had followed only the smell of the honey,
they would have flown to the red glass, but they did
not. They went first to the blue glass, expecting to
find the honey on the usual colour, and it wa?

/**-■"-=:.

'. ■-: .:si:::i: «■::-:•: zi^lz zs.ty went off to

•: . ::::-:. -. .:.::.i '\i' zzt r right pleasant

: - r.:i:'.r :: f. -. trf. irt r:-: onlv orna-

:.:.- ". :■: irt :.Siri_ ini i::r.g their part

.s \ : '-^1': .m: ? rt: scer.is can do.

• :■ -:•:•: :'•: irl.r. :-> 5n:e!I which

'« ' ■ "- .c^'-'ictt. rh'.'T'.e. roseniarv,

.. -s;:" . — .r; :r.r 5r/.^l hiiier. bunches

.--«■" .* ^:cr. z'r.t zzr.y r.o'.vers of the

-.. :.:.■> *^ i ::-r.I another way of

-^.:> :': .Tj-vr r.: r.eec of bright

- -».-. ■: ^ : J -.i j^ :r.:e anc certain a

■i; ^.- ~si-.: :: '■:*-: once begin to

-' .1- >.::r j,r.L ivM or dark-

- ;•■ s :-::->rrr.:ri. -.vhile graiidy flow-

, : : ;\^". :vr. ir..: ho'.'.vhock. have
......... ...^. ^^ .,, .y.^ world we

. . L j-T/.ir.c t.^ attract others

■ ^. *: ;;-i"?>. /.ever::e>s, kindliness,

:s ■ L r.:*. '. 5:r::e r.owers. like the

: > . ." ' >i- .i:::l :he celicate hya-

;. : :.;..' ;.- ' >:;:::: ar.o. graceful shapes

';■.:: • : .-.-: :'..: ;■ ;:: :'.;..ir*.y a: an end of the con-
:r:-. .i:'^:v> * -' "c'^ :^ >c\:v.rc :;:e visits of insects.
1 1 :i V y ,^ V. V. : ; V > c rv c : : :•. .-.: v*. : r: orent flowers open
ail*, c'.oso a: ^■.irrcTo::: :i:v.c>: The daisy receives its
r.air.o. i:\;;.V ■.■\i\ 'H'cav.so i: o'pens at sunrise and
cl'jses at sunset, wr.ilo t::o even in i:: primrose {(Enothcni
biennis) and the night campion [Silcnc noctillora)

BEES AND FLOWERS. 225

spread out their flowers just as the daisy is going to
bed.

What do you think is the reason of this? If you
go near a bed of evening primroses just when the sun
is setting, you will soon be able to guess, for they will
then give out such a sweet scent that you will not
doubt for a moment that they are calling the evening
moths to come and visit them. The daisy opens by
day, because it is visited by day insects, but those
particular moths which can carry the pollen-dust of
the evening primrose, fly only by night, and if this
flower opened by day other insects might steal its
honey, while they would not be the right size or shape
to touch its pollen-bags and carry the dust.

It is the same if you pass by a honeysuckle in the
evening ; you will be surprised how much stronger its
scent is than in the day-time. This is because the
sphinx hawk-moth is the favourite visitor of that flow-
er, and comes at nightfall, guided by the strong scent,
to suck out the honey with its long proboscis, and
carry the pollen-dust.

Again, some flowers close whenever rain is coming.
The pimpernel (Anagallis arvensis) is one of these,
hence its name of the " Shepherd's Weather-glass."
This little flower closes, no doubt, to prevent its
pollen-dust being washed away, for it has no honey;
while other flowers do it to protect the drop of honey
at the bottom of their corolla. Look at the daisies
for example when a storm is coming on; as the sky
grows dark and heavy, you will see them shrink up
and close till the sun shines again. Th^" "" "''s
because in each of the little yellow flore
16

226 THE FAIRY-LAND OF SCIENCE.

tre of the flower there is a drop of honey which would
be quite spoiled if it were washed by the rain.

And now you will see why cup-shaped flowers so
often droop their heads — think of the harebell, the
snowdrop, the lily-of-the-valley, the campanula, and
a host of others; how pretty they look with their
bells hanging so modestly from the slender stalk!
They are bending down to protect the honey-glands
within them, for if the cup became full of rain or dew
the honev would be useless, and the insects would
cease to visit them.

But it is not only necessary that the flowers should
keep their honey for the insects, they also have to
take care and keep it for the right kind of insect.
Ants are in many cases great enemies to them, for
thev like honev as much as bees and butterflies do,
yet you will easily see that they are so small that if
they creep into a flower they pass the anthers without
rubbing against them, and so take the honey without
doing any good to the plant. Therefore w-e find
numberless contrivances for keeping the ants and other
creeping insects away. Look for example at the hairy
stalk of the primrose flower ; those little hairs are like
a forest to a tiny ant, and they protect the flower from
his visits. The Spanish catchfly (Silene otites)^ on the
other hand, has a smooth, but very gummy stem, and
on this the insects stick, if they try to climb. Slugs
and snails too wnll often attack and bite flowers, un-
less they are kept away by thorns and bristles, such
as we find on the teazel and the burdock. And so
we are gradually learning that everything which
a plant does has its meaning, if we can only find

BEES AND FLOWERS. 227

it out, and that even every insignificant hair has
its own proper use, and when we are once aware
of this a flower-garden may become quite a new
world to us if we open our eyes to all that is going
on in it.

But as we cannot wander among many plants to-
day, let us take a few which the bees visit, and see
how they contrive not to give up their honey without
getting help in return. We will start with the blue
wood-geranium, because from it we first began to
learn the use of insects to flowers.

More than a hundred years ago a young German
botanist, Christian Conrad Sprengel, noticed some soft
hairs growing in the centre of this flower, just round
the stamens, and he was so sure that every part of a
plant is useful, that he set himself to find out what
these hairs meant. He soon discovered that they
protected some small honey-bags at the base of the
stamens, and kept the rain from washing the honey
away, just as our eyebrows prevent the perspiration
on our faces from running into our eyes. This led
him to notice that plants take great care to keep their
honey for insects, and by degrees he proved that they
did this in order to tempt the insects to visit them
and carry off their pollen.

The first thing to notice in this little geranium
flower is that the purple lines which ornament it all
point directly to the place where the honey lies at
the bottom of the stamens, and actually serve to lead
the bee to the honey ; and this is true of the veins
and marking of nearly all flowers except of those

228 "^li^ FAIRY-LAND OF SCIENCE.

which open by night, and in tliese they would be useless,
for the hisccts would not see than.

When the geranium first opens, all its ten stamens
are lying flat on the corolla or coloured crown, as in
the left-hand tlower in Fig. 62, and then the bee can-
not get at the honey.
But in a short time
five stamens begin to
raise themselves and
cling round the stig-
ma or knob at the top
of the seed-vessel, as
in the middle flower.
Xow you would think
they would leave their
dust there. But no!
the stigma is closed
up so tight that the
dust cannot get on to
the sticky part. Now,
Yu: (,2.—c,^ra,„i,m ivfr^/ifuw the however, the bee can
Uo(j(i Geranium. In the lefl-

hand flower the slamens are all ^^^ ^^ *"^ honey-
lying down. In the middle glands on the OUtside
fion-er five stamens clasp the of the raised Stamens ;
stigma. In the right - hand a^j ^g ^e sUcks it, his
oner e s igma is open a er |jg^,j^ tOUches the an-
thers or dust -bags,
and he carries off the pollen. Then, as soon as all
the dust is gone, these five stamens fall down, and the
other five spring up. Still, however, the stigma re-
mains closed, and the pollen of these stamens, too,
may be carried away to another flower. At last these

BEES AND FLOWERS. 229

five also fall down, and then, and not till then, the
stigma opens and lays out its 'five sticky points, as
you may see in the right-hand flower, Fig. 62.

But its own pollen is all gone, how then will it get
any? It will get it from some bee who has just taken
it from another and younger flower; and thus you
see the blossom is prevented from using its own pollen,
and made to use that of another blossom, so that its
seeds may grow healthy and strong.

The garden nasturtium, into whose blossom we saw
the humble-bee poking its head, takes still more care
of its pollen-dust. It hides its honey down at the end
of its long spur, and only sends out one stamen at a
time instead of five like the geranium ; and then, when
all the stamens have had their turn, the sticky knob
comes out last for pollen from another flower.

All this you may see for yourselves if you find
geraniums * in the hedges, and nasturtiums in your
garden. But even if you have not these, you may
learn the history of another flower quite as curious,
and which is found in any field or lane in England, and
is not uncommon in America. The common dead-net-
tle (Fig. 63) takes a great deal of trouble in order that
the bee may carry off its pollen. When you have found
one of these plants, take a flower from the ring all
round the stalk and tear it gently open, so that you can
see down its throat. There, just at the very bottom,
you will find a thick fringe of hairs (/, No. 2, Fig. 63),

* The scarlet and other bright geraniums of our flower-gar-
dens kre not true geraniums, but pelargoniums. You may,
however, watch all these peculiarities in them if you cannot
procure the true wild geranium.

Z30

THE FAIRY-LAXD OF SCIEN^CE.

and you will guess at once that these are to protect a
drop of honey below. Little insects which would
creep into the flower and rob it of its honey without
touching the anthers of the stamens (a, Fig. 63) can-

FlG. 63.— Flower of the Dead-Nettle {Lamium album). I, Whole.
2, CuL in half. /, Fringe of hairs protecting honey at base.
J, Stigma, a. Anthers of stamens. /, Lip of flower.

not get past these hairs, and so the drop is kept till
the bee comes to fetch it.

Now look for the stamens : there are four of them
(a a), two long and two short, and they are quite
hidden under the hood which forms the top of the
flower. How will the bee touch them? If you were

^ BEES AND FLOWERS, 23 1

to watch one, you would find that when the bee
ah'ghts on the broad lip /, and thrusts her head down
the tube, she first of all knocks her back against the
little forked tip s. This is the sticky stigma, and she
leaves there any dust she has brought from another
flower; then, as she must push far in to reach the
honey, she rubs the top of her back against the anthers
a a, and before she comes out again has carried away
the yellow powder on her back, ready to give it to
the next flower.

Do you remember how we noticed at the beginning
of the lecture that a bee always likes to visit the same
kind of plant in one journey? You see now that this
is very useful to the flowers. If the bee went from
a dead-nettle to a geranium, the dust would be lost,
for it would be of no use to any other plant but a dead-
nettle. But since the bee likes to get the same kind
of honey each journey, she goes to the same kind
of flowers, and places the pollen-dust just where it is
wanted.

There is another flower, called the Salvia, which
belongs to the same family as our dead-nettle, and I
think you will agree with me that its way of dusting
the bee's back is most clever. The Salvia (Fig. 64) is
shaped just like the dead-nettle, with a hood and a
broad lip, but instead of four stamens it has only two,
the other two being shrivelled up. The two that are
left have a very strange shape, for the stalk or ^/a-
mcnt of the stamen (i /) is very short, while the anther,
which is in most flowers two little bags stuck together,
has here grown out into a long thread a b, with a
little dust-bag at one end only. In i, Fig. 64, '

232

THE FAIRY-LAND OF SCIENCE.

only st^c one of these stems, because the flower is c
in half, but in the whole flower, one stands o
side just within the lip. Now, when the bee puts 1
head into the tube to reach the honey, she passesd

Fig. 64.— Flower of the Salvia. 1. Half a flower, showing the;
filament /, the swingiog anther a 6, 11 a , and the Stigma j,
a. Bee entering the flower pushes the anther so tha
the position a 6' , No. i, and hits him on the back. 3. Olderi
flower : stigma touching the bee.

right between these two swinging anthers, and knock-J
ing against the end b pushes it before her and so bring!
the dust-bag a plump down on her back, scattering
the dust there ! You can easily try this by thrustin
a pencil into any Salvia flower, and you will see th<3
anther fall.

You will notice that all this time the bee does noj
touch the sticky stigma which hangs high above hei
but after the anthers are empty and shrivelled the
of the stigma grows longer, and it falls lower dow
By-and-hy another bee, having pollen on her bacfj

BEES AND FLOWERS. 233

comes to look for honey, and as she goes into No. 3,
she rubs against the stigma and leaves upon it the dust
from another flower.

Tell me, has not the Salvia, while remaining so
much the same shape as the dead-nettle, devised a
wonderful contrivance to make use of the visits of
the bee?

The sweet white violet (Viola blandd) or the dog
violet {Viola canina), which you can gather in any
meadow, give up their pollen-dust in quite a different
way from the Salvia, and yet it is equally ingenious.
Everyone has noticed what an irregular shape this
flower has, and that one of its petals has a curious
spur sticking out behind. In the tip of this spur
and in the spur of the stamen lying in it the violet
hides its honey, and to reach it the bee must press
past the curious ring of orange-tipped bodies in the
middle of the flower. These bodies are the an-
thers a a. Fig. 65, which fits tightly round the stig-
ma Sy so that when the pollen-dust /», which is very
dry, comes out of the bags, it remains shut in by the
tips as if in a box. Two of these stamens have
spurs which lie in the spur of the flower, and have
honey at the end of them. Now, when the bee
shakes the end of the stigma s, it parts the ring of
anthers, and the fine dust falls through upon the
insect.

Let us see for a moment how wonderfully this flow-
er is arranged to bring about the carrying of the
pollen, as Sprengel pointed out years ago. In the first
place, it hangs on a thin stalk, and * ' * '— d down
so that the rain cannot come the

234

THE FAIRY -LAND OF SaSNCE.

Spur, and also so that the pollen-dust falls forward
into the front of the little box made by the closed
anthers. Then the pollen is quite dry, instead of being
sticky as in most plants. This is in order that it may
fail easily through the cracks. Then the style or stalk
of the stigma is very thin and its tip very broad, so
that it quivers easily when the bee touches it, and so
shakes the anthers apart, while the anthers themselves
fold over to make the box and yet not so tightly but

Fig. 65.— Section of the Dog Violet. Lubbock A, Anthers
stigma enlarged, a a. Anthers, s. Stigma. /, Pollen,

that the dust can fall through when they are shaken.
Lastly, if you look at the veins of the flower, you will
find that they all point toward the spur where the
honey is to be found, so that when the sweet smell of

BEES AND FLOWERS.

235

the flower has brought the bee, she cannot fail to go
in at the right place.

Two more flowers still I want us to examine to-
gether, and then I hope you will care to look at every
flower you meet, to try and see what insects visit it, and

Fig, bb.— Lotus corniculahis, Bird's-foot Trefoil. I. Fu!] flower:
sta, SUndard : u\ Wings : k. Keel. 2. Keel of flower : d.
Depression into which wings fil. 3. Inlerior of flower : j,
Stigma ; /. Pollen ; a, Anthers ; h. Place where honey lies.

how its pollen-dust is carried. These two flowers are
the common Bird's-toot trefoil (Lotus comiculatus) and
the Early Orchis (Orchis vtascuh).

The Bird's-foot trefoil, Fig.66,* you will find almost

• This plant is not found wild
I the flower may be studied, though \

1 America, but the parts of
ith slight differences, in the

236 THE FAIRY'LAND OF SCIENCE,

anywhere all through the summer, and you will know
it from other flowers very like it by its leaf, which is
not a true trefoil, for behind the three usual leaflets
of the clover and the shamrock leaf, it has two small
leaflets near the stalk. The flower, you will notice,
is shaped very like the flower of a pea, and indeed it
belongs to the same family, called the Papilionacece or
butterfly family, because the flowers look something
like an insect flying.

In all these flowers the top petal (sta. Fig. 66)
stands up like a flag to catch the eye of the insect,
and for this reason botanists call it the " standard."
Below it are two side-petals w called the " wings," and
if you pick these off you will find that the remaining
two petals k are joined together at the tip in a shape
like the keel of a boat (2, Fig. 66). For this reason
they are called the " keel." Notice as we pass that
these two last petals have in them a curious little
hollow or depression d, and if you look inside the
" wings " you will notice a little knob that fits into
this hollow, and so locks the two together. We shall
see by-and-by that this is important.

Next let us look at the half-flower when it is cut
open, and see what there is inside. There are ten
stamens in all, inclosed with the stigma in the keel ;
nine are joined together and one is by itself. The
anthers of five of these stamens burst open while the
flower is still a bud, but the other stamens go on grow-
ing, and push the pollen-dust, which is very moist
and sticky, right up into the tip of the keel. Here
you see it lies right round the stigma s, but as we
saw before in the geranium, the stigma is not ripe

BEES AND FLOWERS, 237

and sticky yet, and so it does not use the pollen-
grains.

Now suppose that a bee comes to the flower. The
honey she has to fetch lies inside the tube at h, and
the one stamen being loose she is able to get her
proboscis in. But if she is to be of any use to the
flower she must uncover the pollen-dust. See how
cunningly the flower has contrived this. In order to
put her head into the tube the bee must stand upon
the wings w, and her weight bends them down. But
they are locked to the keel k by the knob fitting in
the hole d, and so the keel is pushed down too, and
the sticky pollen-dust is uncovered and comes right
against the stomach of the bee and sticks there! As
soon as she has done feeding and flies away, up go
the wings and the keel with them, covering up any
pollen that remains ready for next time. Then when
the bee goes to another flower, as she touches the
stigma as well as the pollen, she leaves some of the
foreign dust upon it, and the flower uses that rather
than its own, because it is better for its seeds. If
however no bee happens to come to one of these
flowers, after a time the stigma becomes sticky and it
uses its own pollen : and this is perhaps one reason
why the bird's-foot trefoil is so very common, because
it can do its own work if the bee does not help it.

Now we come lastly to the Orchis flower.* Mr.
Darwin has written a whole book on the many curi-
ous and wonderful ways in which orchids tempt bees
and other insects to fertilize them. We can only take
the simplest, but I think you will say that even this

* The nearest species for study in America are the Habenarias.

THE FAIRY-LAND OF SCIENCE.

W 238

^M blossom is more like a conjuror's box than you wouldl

H have supposed it possible that a flower could be.

H Let us examine it closely. It has six deep-red

Fig. tT.—Oi-cAis mascula. tfr, Calyx, cs. co. co. Corolla. pA
Poll en- masses, r. Rostellum or lid covering ihe knob atj
the end of pollen -masses. / s. Stigmas. P, a Pollinia otT
pollen-mass, of which a ia the pollen and rf is the sticky^
gland which adheres to the head of Ihe bee. sv, Seed-v
sei. sp. Spur of the flower.

calyx or outer cup, the three co, co, co, belonging t
the corolla or crowTi of the flower; but all six j
coloured alike, except that the large one in front,!
called the " lip," has spots and lines upon it which willi
suggest to you at once that they point to the honey.I
But where are the anthers, and where is the stig;ma?j

BEES AND FLOWERS,

239

Look just under the arch made by those three
bending flower-leaves, and there you will see two
small slits, and in these some little club-shaped bodies
p py which you can pick out with the point of a needle.
One of these enlarged is shown at P. It is composed
of sticky grains of pollen a held together by fine
threads on the top of a thin stalk ; and at the bottom
of the stalk there is a little round body d. This is
all that you will find to represent the stamens of the
flower. When these masses of pollen, or pollinia as
they are called, are within the flower, the knob at the
bottom is covered by a little lid r, shutting them in
like the lid of a box, and just below this lid r you will
see two yellowish lumps sSy which are very sticky.
These are the top of the stigma, and they are just
above the seed-vessel sv, which you can see in the
lowest flower in the picture.

Now let us see how this flower gives up its pollen.
When a bee comes to look for honey in the orchis,
she alights on the lip, and guided by the lines makes
straight for the opening just in front of the stigmas
s s. Putting her head into this opening she pushes
down into the spur spy where by biting the inside skin
she gets some juicy sap. Notice that she has to bite,
which takes time.

You will see at once that she must touch the
stigmas in going in, and so give them any pollen she
has on her head. But she also touches the little lid r,
and it flies instantly openy bringing the glands d at the
end of the pollen-masses against her head. These glands
are moist and sticky, and while she is gnawi?

240

THE FAIRY-LAND OF SCIENCE.

inside of the spur they dry a little and cling to her
head and she brings them out with her. Darwin once
caught a bee with as many as sixteen of these pollen-
masses clinging to her head.

But if the bee went into the next flower with these
poUinia sticking upright, she would simply put them
into the same slits in the next flower, she would not
touch them against the stigma. Nature, however, has
provided against this. As the bee flies along, the
glands sticking to its head dry more and more, and as
they dry they curl up and drag the pollen-masses
down, so that instead of standing upright, as in i,
Fig. 67, they point forward, as in 2.

And now, when the bee goes into the next flower,
she will thrust them right against the sticky stigmas,
and as they cling there the fine threads which hold
the grains together break away, and the flower is
fertilized.

If you will gather some of these orchids during
your next spring walk in the woods, and will put a
pencil down the tube to represent the head of the bee,
you may see the little box open, and the two pollen-
masses cling to the pencil. Then if you draw it out
you may see them gradually bend forward, and by
thrusting your pencil into the next flower you may see
the grains of pollen break away, and you will have
followed out the work of the bee.

Do not such wonderful contrivances as these make
us long to know and understand all the hidden work
that is going on around us among the flowers, the
insects, and all forms of life ? I have been able to tell

BEES AND FLOWERS.

241

you but very little, but I can promise you that the
more you examine, the more you will find marvellous
histories such as these in simple field-flowers.

Long as we have known how useful honey was to
the bee, and how it could only get it from flowers,
yet it was not till quite lately that we have learned to
follow out Sprengel's suggestion, and to trace the use
which the bee is to the flower. But now that we have
once had our eyes opened, every flower teaches us
something new, and we find that each plant adapts
itself in a most wonderful way to the insects which
visit it, both so as to provide them with honey, and at
the same time to make them unconsciously do it good
service.

And so we learn that even among insects and
flowers, those who do most for others, receive most
in return. The bee and the flower do not either of
them reason about the matter, they only go on living
their little lives as nature guides them, helping and
improving each other. Think for a moment how it
would be, if a plant used up all its sap for its own life,
and did not give up any to make the drop of honey
in its flower. The bees would soon find out that
these particular flowers were not worth visiting, and
the flower would not get its pollen-dust carried, and
would have to do its own work and grow weakly and
small. Or suppose, on the other hand, that the bee bit
a hole in the bottom of the flower, and so got at the
honey, as indeed they sometimes do ; then she would
not carry the pollen-dust, and so would not keep up
the healthy strong ^' * * ' make her daily food.

But this, as On the con-

242

THE FAIRY-LAND OF SCIENCE.

trary, the flower feeds the bee, and the bee quite
unconsciously helps the flower to make its healthy
seed. Xav more: when vou are able to read all that
has been written on this subject, you will find that
we have good reason to think that the flowerless
plants of the Coal Period have gradually put on the
beautiful colours, sweet scent, and graceful shapes of
our present flowers, in consequence of the necessity of
attracting insects, and thus we owe our lovely flowers
to the mutual kindliness of plants and insects.

And is there nothing beyond this ? Surely there
is. Flowers and insects, as we have seen, act without
thought or knowledge of what they are doing; but
the law of mutual help which guides them is the same
which bids you and me be kind and good to all those
around us, if we would lead useful and happy lives.
And when we see that the Great Power which rules
^ver our universe makes each work for the good of all,
even in such humble things as bees and flowers ; and
that beauty and loveliness come out of the struggle
and striving of all living things ; then, if our own life
be sometimes difficult, and the struggle hard to bear,
we learn from the flowers that the best way to meet
our troubles is to lay up our little drop of honey
for others, sure that when they come to sip it they
will, even if unconsciously, give us new vigour and
courage in return.

And now we have arrived at the end of those sub-
jects which we selected out of the Fairy-land of Sci-
ence. You must not for a moment imagine, how-
ever, that we have in any way exhausted our fairy

BEES AND FLOWERS.

243

domain; on the contrary, we have scarcely explored
even the outskirts of it. The ** History of a Grain of
Salt," " A Butterfly's Life," or " The Labours of an
Ant," would introduce us to fairies and wonders quite
as interesting as those of which we have spoken in
these lectures. While " A Flash of Lightning," " An
Explosion in a Coal-mine," or " The Eruption of a
Volcano," would bring us into the presence of ter-
rible giants known and dreaded from time imme-
morial.

But at least we have passed through the gates, and
have learned that there is a world of wonder which we
may visit if we will ; and that it lies quite close to us,
hidden in every dewdrop and gust of wind, in every
brook and valley, in every little plant or animal. We
have only to stretch out our hand and touch them
with the wand of inquiry, and they will answer us
and reveal the fairy forces which guide and govern
them; and thus pleasant and happy thoughts may
be conjured up at any time, wherever we find our-
selves, by simply calling upon nature's fairies and
asking them to speak to us. Is it not strange, then,
that people should pass them by so often without a
thought, and be content to grow up ignorant of all
the wonderful powers ever active in the world around
them?

Neither is it pleasure alone which we gain by a
study of nature. We cannot examine even a tiny
sunbeam, and picture the minute waves of which it
is composed, travelling incessantly from the sun, with-
out being filled with wonder and awe at the marvellous
activity and power displayed in the infinitely small as

244

THE FAIRY-LAND OF SCIENCE.

well as in the infinitely great things of the universe.
We cannot become familiar with the facts of gravi-
tation, cohesion, or crystallization, without realizing
that the laws of nature are fixed, orderly, and con-
stant, and will repay us with failure or success ac-
cording as we act ignorantly or wisely; and thus we
shall begin to be afraid of leading careless, useless, and
idle lives. We cannot watch the working of the fairy
" life " in the primrose or the bee, without learning
that living beings as well as inanimate things are
governed by these same laws of nature; nor can we
contemplate the mutual adaptation of bees and flow-
ers without acknowledging that it teaches the truth
that those succeed best in life who, whether conscious-
ly or unconsciously, do their best for others.

And so our wanderings in the Fairy-land of Sci-
ence will not be w^asted, for we shall learn how to
guide our own lives, while we cannot fail to see that
the forces of nature, whether they are apparently me-
chanical, as in gravitation or heat ; or intelligent, as
in living beings, are one and all the voice of the Great
Creator, and speak to us of His Nature and His Will.

I NDEX.

Adelsberg stalactite grotto,

121.

Aerial ocean, 53, 73.

Agassiz on ** erratic blocks," 127.

Air, bad, in close rooms, 57.

carrying water-vapour, 77,

78, 81, 96.

elasticity of, 61.

its pressure on the earth, 64.

made of two gases, 55.

rising of hot, 72.

weight of, 62.

Air-atoms, forming waves of

sound, 135.
Air-bubbles bursting in waves,

148.
Air-currents, cause of, 71.
Albuminoids, 157, 164.
Almond-seed, 156.
Alum Bay Chine, 116.
Ammonia in air, 58.
Anaxagoras on size of the sun, 29.
Antarctic Continent, snowfields

of, 97.
Anthers of stamens, 168.

bursting of, 170.

Aqueous vapour, whence it comes,

80.
Arbroath, waste of cliffs at, 122.

Ariel's song, 5.

Atmosphere causing the spread of
light, 74.

height of, 62.

weight of, 64-70.

Aurora borealis, 55, 75.
Avalanche, noise of, 152.

Balloon ascents, 62.

Balls illustrating soundwaves, 133.

Barometer and its action, 67-70.

Bee-bread, 209.

Bee, pollen-masses on head of,

239-
Bees and flowers useful to each

other, 242.

and orchids, 237.

cementing dead bodies, 217.

feeding of, 210, 212.

Huberon, 202,

length of life of, 217.

nursing, 206.

sentinel, 217.

swarming, 203, 213, 214.

ventilating, 216.

visit one set of flowers at a

time, 221, 231.
worker, queen, and drone.

204.

245

246

INDEX.

Bees, young princess, 212.
Beetles, timber-boring, 152.
Biot, Professor, on sound in tubes,

137.
Bird's-foot trefoil, structure of,

235-
Birds, trill of, 153.

Bischoff, on lime in River Rhine,

112.
Blackgang Chine, 116.
Bones of the ear, 142.
Bonn, solid matter carried past,

112.
Breathing and burning, 57.
Brood-comb of bees, 211.
Brook, song of the, 148.
Burning and breathing, 57.
Buttercup, honey-glands in, 222.
Buxton, Poole's Cavern, near, 120.

Calamites of the coal, 184.
Calyx, use of, 166.
C'afions of Colorado, 116.
Carbon in plants, 162.

in sugar, 163.

C'arhoiuitc of lime crystals, 120.
(!arl)()nic acid in air, 58.
(lardboard of colours, revolving,

41.
C'arruthers, Mr., cited, 181, 184.
Caverns, stalactitic, 121.
Caves on sea-shore, 122.
Cells of a plant, 158.

of bees, 207.

Chalk-builders, 4, 100.
Chemical action, 12, 16, 56.

rays, 48.

Chlorophyll in leaves, 161.
Cissy and the drops, 14.

City of the bees, 200.
Clerk-Maxwell on ether, 35.
Clouds, how formed, 78, 81.
Club-mo'ss and coal-plants, 182.
Coal, a piece of, 175.

essences from, 195.

imprisoned fairies in, 11.

its growth and purity, 1S6,

188.

oils, tar, and gas of, 191.

ball, contents of a, 181.

forest, picture of a, 183.

gas, making of, 191.

mine, section of a, 177.

Coal-plants, what they have done

for us, 195.
Cobwebs and dewdrops, 87.
Cochlea of ear, 144.
Cocoon of bees, 2 10-21 1,
Cohesion and its work, 8, 12,

83.
Coke, 191.

Colorado cafions, 116.
Colour, bees distinguish, 223.
Colours, cause of, 44.

revolving disk of, 41.

Coral, Huxley on, 21.

picture of, 20.

island, 23.

Corolla, use of, 170.
Corti's organ, 144.
Country, sounds of the, 131.
Crevasses, 126.
Crystallization, 90, 92.

a fairy force, 10.

Crystals in sugar-candy, 89.

how they form, 92.

in many substances, 90,

of sea-salts, 100.

INDEX.

247

Crystals of snow, 93.
Cumberland, rain in, 84.

Daisy, opening of the, 224.

closing in rain, 225.

Darwin, Mr., cited, 237-240.
Dead-nettle, structure of the, 229,

230.
Deltas, 119.

Deposition of mud, 119.
Dew, how formed, 86.

artificial, 87.

Distillation of water from sea, 96.
Drones, slaughter of, 215.

Ear, construction of the, 141.

stones, 143.

Earth, its size compared to the
sun, 29.

Earth-pillars, picture of, 106.

Earth's state if there were no sun,
28.

Echoes, 138, 139.

Eggs, laying of queen-bee, 211.

Enemies of bees, 217.

of plants, 226.

Equisetum, or horse-tail, 185.

Erratic blocks, 127.-

Ether, waves of the, 35, 85.

Eustachian tube, 142.

Evaporation from rivers and seas,
80.

Evening primrose, insects visit-
ing, 224.

Eye, light-waves entering, 38-42.

Fairies, or forces of nature, 6-12.
Fairy " Life," 173.
Fairy-tales and science, 2,

Flowers bright to attract insects,
223.

times of opening of, 224.

Food of a plant, 159.

Frost bursting water-pipes, 95.

breaking up the fields, 124.

Ganges Delta, 119.
Gas, definition of a, 15.

in coal, 190.

Gay-Lussac's balloon ascent, 62.
Geikie, Mr., cited, 122.
Geneva, mud in lake of, 126.
Geranium, fertilization of, 227,

sylvaticum, 228.

of the garden, 229.

Glacial Period, 128.
Glaciers, 98, 124.

blocks carried by, 127.

Glaisher's balloon ascent, 62, 66.

God in nature, 25.

Graphite, hardened by pressure,

190.
Grass, dew forming on, 86.
Gravesend, mud-banks at, 119.
Gravitation and its work, 8, 12.
Great Dismal Swamp, America,

186.
Greenland, glaciers of, 124.

snow-fields of, 97.

vapour carried from, 82.

Gulf of Mexico, vapour carried up

from, 82.

Hailstones, how formed, 88.
I Hard water, 99.
' Hartshorn, spirits of, 58.
i Heat, a fairy force, 8.

cut off by water-vapour, 85.

248

INDEX.

Heat necessary to turn water into

vapour, 96.

of the sun, 32,

work done by, 46.

imprisoned in coal, 47.

of our bodies, 46.

Helpfulness, mutual, of insects

and flowers, 242.
Herschel, Sir J., on the sun, 32.
Hive-bee, forming cells, 207,
Hives, ventilation of, 216.
bees cementing cracks in,

204.
Hoar-frost, 94.
Honey, carried by bee, 208.
secreted by flowers for bees,

222.

use of, to the primrose, 171.

Honeysuckle, scent at night, 225.
Hooker, Sir J., on rainfall, 83.
Horse-tails and calamites, 185.
Huber on bees, 202.
Huxley, Mr., on coral, 21.

cited. III.

Huyghens on light, 34.

Ice, formed of pressed snow, 97.

purity of, 98.

sculpturing power of, 124.

water-flowers in, 95.

Icebergs, 98.

Imagination in science, 7.
Indian Ocean, vapour carried up

from, 80.
Insects attracted by scent and

colour, 224.

buzzing of, 152.

visiting the primrose, 171.

Iron, use of, in leaves, 161.

Iron worked in Sussex, 197.
Ives, Lieut., on Caiions, 117.

Jar, resonance in a, 149.
Judd, Professor, cited, 178.

Kentucky, Mammoth Cave of,

121.
Kettle, crust in a, 112.

vapour rising from a, 78,

Khasia Hills, rain in, 83.

Lace, photographed during lec-
ture, 48.

Lake-district, rain in the, 84.

Land-breeze and sea-breeze, 73.

Landslips, 109.

Lamium album, 230.

Larva of bees, 210.

Laws of nature, 24.

Leather wetted, lifting a weight,
65.

Leaves, oxygen-bubbles rising
from, 162.

stomates in, 165.

the stomach of a plant, 165.

Lepidodendrons, trees of coal,
181, 183, 185.

Life of a plant, 173.

Light, coloured spectrum of, 39.

dark and light bands of, 37.

of the sun, 31.

effect of, on plants, 45.

reflection of, 43.

scattered by particles in air,

74.
Light-waves entering the eye, 39,

size of, 38.

Lightning, 55, 75.

INDEX,

249

Lime, carbonate of, petrifying,

120.
Limpet clinging to a rock, 65.
Liquid, definition of a, 15.
Lines in flowers, 227.
Llanberis Pass, 127.
Looking-glass, cause of reflection

in, 44.
Lotus comiculatus, 235.
Lubbock, Sir J., cited, 223, 234.
Lycopodium like coal-plants, 182.

Magnets, attraction and repul-
sion of, 91.
Martineau, Miss C, on echoes,

139-
Mediterranean, vapour carried up

from, 82.
Mercury, action of, in a barometer,

68.
Metal reflecting light, 44.
Meteors, height of atmosphere

shown by, 63.
Mississippi delta, 119.
Moraines, 125.

Mountains causing rainfall, 83.
Mouse breathing in bell-jar, 57.
Mud in river-water, 112.
Musical notes, 144, 145-147.

Nasturtium and the bee, 229.
Nature and her laws, 24.

love of, 19.

Neath Colliery, fossils from, 178.
Newton on light, 34.
Nile plain and delta, 119.
Nitre crystals, how to make, 90.
Nitrogen in air, 56.
Nodules in coal, 180.

Noise and music, 145.

Norfolk, Virginia, Dismal Swamp

in, 186.
Notes of music, 146.

Oil, its heat and light, 47.

wells, 192.

Oils in coal, 190, 191.

in plants, 157, 163, 192.

Orange-cells, 158.
Orchis mascula, its structure, 237.
Otoliths, or ear-stones, 143.
Ovules of plants, 166.
Oxygen in air, 56.

Pan-pipes, 150.

Paper, pressure of air on square

inch of, 64.
Paraffin from coal, 192.
Peat, formation of, 187.
Petrifactions, 120.
Pelai^oniums, 229.
Pennine Hills causing rainfall,

84.
Peter Bell on a primrose, 7.
Phosphoric acid, 56.
Phosphorus burning in air, 56.
Photography, 48.
Pimpernel, closing for rain, 225.
Plant-cells, 158.
Plant, food of a, 159.

water rising in a, 160.

Plants absorbing rain, 84.

annual and perennial, 165.

contrivances for protection

in, 226.

effect of light on, 45.

fertilized by wind, 222.

in a coal-mine, 177.

250

INDEX,

Plants, light and heat imprisoned

in, 173.

remains in coal-nodules, 180.

Poker, sound of a vibrating,

133.
Pollen-dust carried by bees, 222.

of flowers, 234, 236.

Pollen, gathering of, 208.

use of, 168.

PoUinia of an orchis, 238.

Polyps, coral, 2i.

Poole's Cavern, 120.

Popgun, compressing air in, 61.

Potash formed, 17.

Potassium in water, 16.

Pot-holes, 115.

Pressuie, making coal hard, 190.

Primrose, corolla falling off, 170.

Protoplasm, 159.

green granules of, 161.

Primrose, the life of a, 154.

two forms of, 167.

Princess-bees, slaughter of, 215.

Prism giving coloured light, 39.

Propolis, or bee-cement, 204.

Queen-bee, flight of, 209.
laying eggs, 210.

Rain, causes of, 82, 83.

fairies working in, 8.

fall of barometer before, 70.

Ravine worn by water, 114.
Reflection of light, 43.
Resonance in ajar, 150.
Rhine, amount of lime carried by,

112.
Roches moutonnees, 126.
Rock hurled by waves, 122.

St. John's Wood, explosion in,

138.
Salvia, bee entering the, 232.
Sap of plants, 161.
Scent of flowers attracts insects,

225.
Science, fairy-tales of, 2.

how to study, 18.

Sculptors, water and ice, 103, 123.
Sea-breeze and land-breeze, 73,
Sea, why salt, 99
what becomes of solid matter

in, 100.
Seeds, how formed, 169.

oils in, 192.

Selaginella, figure of, 182.

Shale, piece of, with plants, 178.

Shelley, cited, 148.

Shell, music of the, 150.

Sigillaria, 179, 183.

Snow, cause of whiteness of, 94.

fairies working in, 9

Snow-crystals, 94.

Snow-drop fairies, 10.

Snowfields, 97.

Snow-flakes, crystallization of, 93.

Solid, definition of a, 15,

Sound, globes of, 137.

its nature, 132.

reflection of, 138.

Sounds of town and country, 130,

132. ^

Sound-waves, 135.

South Ouram, coal-nodules at,
180.

Spectrum, coloured, 40.

Sphinx hawk -moth visiting honey-
suckle, 225.

Spores of club-moss, 182,

INDEX.

251

Spores in coal, 181, 183.
Sprengel on insects and flowers,

227, 233, 241.
Springs, 97.

mineral, 99.

Stalactites, 120.
Stalagmites, 121.
Stamens of a flower, 168.
Starch in plants, 157, 162.
Stars, light of the, 36.

twinkling of, 75.

Stigma of a flower, 169.
Stigmas of orchids, 238.
Stigmaria root, 178.
Stomates in leaves, 165.
Striae made by ice, 126, 127.
Sugar, carbon in, 163.

-candy crystals, 89.

Sun, distance of the, 29.

size of the, 29.

heat and light of, 32.

Sunbeams, 27, 42.

causing colour, 44.

causing wind, 71.

how few reach the earth, 32.

made of many colours, 40.

rate at which they travel, 38.

turning water to vapour, 77,

80.
Sunrise, 27.

Sussex, iron worked in, 197.
Swamp, Great Dismal, 187.
Swarming of bees, 203, 213.
Switzerland, glaciers of, 124.

Tar from coal, 191.
Tennyson's " In Memoriam "

cited, 199.
poem of a flower, 155.

Thames, drainage of, iii.

mud-banks, 119.

Thunder, noise of, 151.

Trade-winds, 73.

Treacle and water mixing through

a membrane, 160.
Trees of the coal-forest, 183.
Trefoil, structure of flower of,

235.
Tumbler of water inverted, 66.

Tuning-forks vibrating, 146.

Turin, moraines near, 125.

Twinkling of stars, 75.

Tympanum of the ear, 142.

Tyndall, Dr., cited, 78, 91, 95,

I33» 149-

Underclays of coal, 179.
Undercliff", Isle of Wight, no.
Undulatory theory of light, 33-35.

Vibration of tuning-forks,

146.
Violet, structure of the, 234.

Wales, rain in, 84.

Water, cutting power of, 111-118.

" hard," 99.

heat required to vaporize, 96.

how it rises in a plant, 160.

in U tube kept up by pres-
sure, 67.
solid matter dissolved in.

112.
Water-dust, 78.
Waterfalls, how formed, 114.
Water-flowers in ice, 95.
Water-pipes, cause of bursting of,

95.

252

INDEX.

Water-vapour invisible, 78, 80.

screening the sun's heat, 85.

Waves, noise of the, 147, 148.

of light measured, 37.

of sound crossing each other,

139.
Wave-theory of light, 33-35.

Wax, plate of, in hive, 206.

formation of, 206.

Weight and pressure of air, 62,

64.

barometer measuring, 67-70.

Wheel revolving to make musical

note, 145.
Williams, Mr. J., cited, 17S,
Wind, cause of, 71.

noise of the, 149-151.

fertilizing plants, 223.

Winds, land and sea, 72.

trade-, 73.

Woodstock Park, echoes in, 139,
Work of the sunbeams, 42.

Young, Dr., cited, 192.

THE END.

S^oS"

(8)

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