Arabella B. Buckley.

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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 manner 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.



Week 23

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
(sigillum, a seal) all up the trunk, due to the scars left by the
leaves when they fell from the tree. You will see the
Sigillarias 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 sane; 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 is the root of the Sigillaria, 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 our
mountain lakes.

But what is that curious reed-like stem we found in the piece of
shale (see Fig. 47)? That stem is very important, for it
belonged to a plant called a Calamite, which, as we shall see
presently, helped to sift the 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. 52, is seldom more than
a foot, and never more than 4 feet high in England, 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. 51), with leaves arranged
in stars round the branches, are only larger copies of the little
marsh-plants; and the seed-vessels of the two plants are almost
exactly the same.

These great trees, the Lepidodendrons, the Sigillarias, and the
Calamites, together with large tree-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 Lipidodendrons 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 began to crowd out the
old giants of the coal-forests, so that they dwindled and
dwindled from century to century 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 marshes 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,
compared to the huge trees and tangled masses of ferns and reeds
which covered the whole ground, or were reflected 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, instead 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 across the Atlantic to the shores of America, and to land
at Norfolk in Virginia, because 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 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 constantly, 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 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
forests, 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
Dismal Swamp, and would keep out all earthy matter, so that year
after year the plants would die and form a thick bed of peat,
afterwards to become coal.



Week 24

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 Mississippi, to
make a layer over the dead plants. You will easily understand
that this mud would have many 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. 46) 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 hundred of feet above the buried
coal-bed b, 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 beautiful plants on the surface.
We cannot tell exactly all the ground over which these forests
grew in England, because some of the coal they made has been
carried away 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 then.

Try and picture to yourselves that on the east coast of
Northumberland and Durham, where all is now black with coal-
dust, and grimy with the smoke of furnaces; and where the noise
of hammers and steam-engines, and of carts and trucks hurrying to
and fro, makes the country re-echo with the sound of labour;
there ages ago in the silent swamp shaded with monster trees, one
thin layer of plants after another was formed, year after year,
to become the coal we now value so much. In Lancashire, busy
Lancashire, the same thing was happening, and even in the middle
of Yorkshire and Derbyshire the sea must have come up and washed
a silent shore where a vast forest spread out over at least 700
or 800 square miles. In Stafford-shire, too, which is now almost
the middle of England, another small coal-field tells the same
story, while in South Wales the deep coal-mines and number of
coal-seams remind us how for centuries and centuries forests must
have flourished and have disappeared over and over again under
the sand of the sea.

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 thousands 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 they escape again give back the
sunbeams in a bright flame. The hard stone coal, on the contrary,
has lost a great part of these oils, 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. 53). This is the way all our gas 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 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 coal in a fire, and making little black
bubbles which burst and burn. It is from this tar that James
Young first made the paraffin oil we burn in our lamps, and the
spirit benzoline comes from the same source.

From benzoline, 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 sweets which children like to well, are
actually flavoured by essences which come out of coal-tar. Thus
from coal we get not only nearly all our heat and our light, but
beautiful colours 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-world now.

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 admire their
beautiful green foliage except a few croaking reptiles, and
little crickets and grasshoppers; and they lived and died all on
one spot, generation after generation, without seeming to do much
good to anything 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 the
iron. We have proof of this in Sussex. The whole country is
full of iron-stone, and the railings of St. Paul's churchyard are
made of Sussex iron. Iron-foundries were at work there as long
as there was wood enough to supply 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 iron-stone 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, almost everything we use could only have
been made with difficulty and in small quantities; and even if we
could have made them it would have been impossible to have sent
them so quickly all over the world without coal, for we could
have had no railways or steamships, 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 our colonies.

In consequence of this we should have remained a very poor
people. Without manufactories and industries we should have had
to live chiefly by tilling the ground, and everyone being obliged
to toil for daily bread, there would have been much less time or
opportunity for anyone to study science, or literature, or
history, or to provide themselves with comforts 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,
England owes her greatness, 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 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



Week 25

Lecture IX
Bees in the Hive

I am going to ask you to visit with me to-day one of the most
wonderful cities with no human beings in it, and yet it is
densely 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 conspicuously 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 follows
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 wait upon her, she would do nothing
but amuse herself. 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.

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 anthill, can we find so busy, so industrious, or
so orderly a community as among the bees? More than a hundred
years ago, a blind naturalist, Francois Huber, set himself to
study the habits of these wonderful insects and with the help of
his wife and an intelligent manservant 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 and the life of its
inhabitants, I think you will acknowledge 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 approaching 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 neighbours 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 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. 54), who never do any work except during one or two days in
their whole lives. But the smaller working bees (1, Fig. 54) begin
to be busy at once. Some fly off in search of 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


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