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THE ADVENTURES OF A GRAIN OF DUST
_STRANGE ADVENTURES IN NATURE'S WONDERLANDS_
THE ADVENTURES
OF A GRAIN OF DUST
BY
HALLAM HAWKSWORTH
AUTHOR OF "THE STRANGE ADVENTURES OF A PEBBLE"
CHARLES SCRIBNER'S SONS
NEW YORK CHICAGO BOSTON
COPYRIGHT, 1922, BY
CHARLES SCRIBNER'S SONS
Printed in the United States of America
C
[Illustration]
JUST A WORD
I don't want you to think that I'm boasting, but I _do_ believe I'm one
of the greatest travellers that ever was; and if anybody, living or
dead, has ever gone through with more than I have I'd like to hear about
it.
Not that I've personally been in all the places or taken part in all the
things I tell in this book--I don't mean to say that--but I do ask you
to remember how long it is possible for a grain of dust to last, and how
many other far-travelled and much-adventured dust grains it must meet
and mix with in the course of its life.
The heart of the most enduring grains of dust is a little particle of
sand, the very hardest part of the original rock fragment out of which
it was made. That's what makes even the finest mud seem gritty when it
dries on your feet. And the longer these sand grains last the harder
they get, as you may say; for it is the hardest part that remains, of
course, as the grain wears down. Moreover, the smaller it gets the less
it wears. If it happens to be spending its time on the seashore, for
example, the very same kind of waves that buffet it about so, waves
that, farther down the beach hurl huge blocks of stone against the
cliffs and crack them to pieces, not only do not wear away the sand
grains, to speak of, but actually save them from wear. The water between
the grains protects them; like little cushions. And the sand in the
finer dust grains carried by the wind is protected by the material that
gathers on its surface.
Why, if a pebble of the size of a hickory-nut may be ages and ages
old--almost in the very form in which you see it,[1] think what the age
of this long-enduring part of a grain of dust must be.
[1] "The Strange Adventures of a Pebble."
Then remember what the ever-changing material on the surface of these
immortal grains is made of; the dust particles of plants and animals, of
buried Caesars and still older ancients, such as those early settlers of
Chapter II.
Finally, if what we call flesh and blood can think and talk, why not a
grain of dust? In fact, what is flesh and blood but dust come back to
life? Says the poet--and the poets know:
"The very dust that blows along the street
Once whispered to its love that life is sweet."
You see it's as likely a thing as could happen--this whole story.
THE GRAIN OF DUST.
(Per H. H.)
CONTENTS
CHAPTER PAGE
I. _The Little Old Man of the Rock_ 1
II. _Some Early Settlers and Their Bones_ 19
III. _The Winds and the World's Work_ 37
IV. _The Bottom-Lands_ 55
V. _What the Earth Owes to the Earthworm_ 75
VI. _The Little Farmers with Six Feet_ 92
VII. _Farmers with Four Feet_ 114
VIII. _Water Farmers Who Help Make Land_ 137
IX. _Farmers Who Wear Feathers_ 162
X. _The Busy Fingers of the Roots_ 186
XI. _The Autumn Stores and the Long Winter Night_ 204
XII. _The Brotherhood of the Dust_ 225
_Index_ 247
THE ILLUSTRATIONS
The author wishes to make special acknowledgment to the following
publishers for their courtesy in supplying illustrations:
The Macmillan Company for the pictures from Tarr and Martin's "College
Physiography" on page 239; Darwin's "Formation of Vegetable Mould" on
page 77.
D. Appleton and Company for the pictures from Gilbert and Brigham's
"Introduction to Physical Geography" on page 94; "Picturesque America"
on page 243.
J. B. Lippincott Company for the pictures from Beard's "American Boy's
Book of Bugs, Butterflies, and Beetles" on page 229; McCook's "Natural
History of the Agricultural Ant of Texas" on pages 206 and 213.
_McClure's Magazine_ for the pictures on pages 149 and 157.
Scientific American Publishing Company for the picture from "Scientific
American Boy at School" on page 227.
Harper and Brothers for the pictures from McCook's "Nature's Craftsmen"
on pages 98, 105, 109, 207, and 208.
_Strand Magazine_ for the pictures on pages 165, 182, and 204.
Charles Scribner's Sons for the pictures from Yard's "Top of the
Continent" on page 5; "Country Life Reader" on pages 9, 64, 85, 114,
186, and 241; Osborn's "Men of the Old Stone Age" on page 33. Hornaday's
"American Natural History" on pages 116, 117, 119, 123, 130, 144, and
225; Seton's "Life Histories of Northern Animals" on pages 123, 129,
147, and 151.
Henry Holt and Company for the pictures from Beebe's "The Bird, Its Form
and Function" on page 167; Salisbury's "Physiography" on pages 55, 71,
and 167.
Carnegie Institution of Washington for the pictures on pages 8 and 69.
University of Nebraska for the picture on page 37.
Columbia University Press for the picture from Wheeler's "Ants and Their
Structure" on page 95.
Houghton Mifflin Company for the pictures from Sharp's "Year Out of
Doors" on page 11; "Riverside Natural History" on page 117; Mill's "In
the Beaver World" on pages 152 and 153.
Ginn and Company for the pictures from Breasted's "Ancient Times" on
page 67; "Agriculture for Beginners" on page 47; Bergen's "Foundation of
Botany" on pages 49, 190, and 197; Bergen's "Elements of Botany" on
pages 193 and 195; Beal's "Seed Dispersal" on page 51.
U. S. Geological Survey for the pictures on pages 21, 22, 23, 30, 31,
and 59.
New York Zoological Society for the pictures on pages 145, 159, and 216.
_School Arts Magazine_ for the picture on page 221.
U. S. Department of Agriculture for the pictures on pages 125 and 189.
American Museum of Natural History for the pictures on pages 20, 24, 26,
139, and 162.
Cassell and Company for the pictures from "Popular History of Animals"
on pages 118, 177, 179, and 217; "Popular Science" on page 242.
Hutchinson for the pictures from "Marvels of the Universe" on pages 92,
101, 103, 141, 169, and 173; "Marvels of Insect Life" on page 211.
The Dunham Company for the picture on page 45.
International Harvester Company for the picture on page 199.
Northern Pacific Railway for the pictures on pages 235 and 237.
THE ADVENTURES OF A GRAIN OF DUST
It will be understood, as stated in the preface, that, like "The Strange
Adventures of a Pebble," this is an autobiography. In other words, it is
the grain of dust itself that tells the story of the life of the soil of
which it is a part.
THE ADVENTURES OF A GRAIN OF DUST
CHAPTER I
(JANUARY)
In truth you'll find it hard to say
How it could ever have been young
It looks so old and grey.
--_Wordsworth._
THE LITTLE OLD MAN OF THE ROCK
Some say it was Leif Ericson, some say it was Columbus, but _I_ say it
was The Little Old Man of the Rock.
And I go further. I say he not only discovered America but Europe, Asia,
and Africa, and the islands of the sea. I'll tell you why.
I. HOW LITTLE MR. LICHEN DISCOVERED THE WORLD
As everybody knows, we must all eat to live, and how could either
Columbus or anybody else--except Mr. Lichen--have done much discovering
in a world where there was nothing to eat? When the continents first
rose out of the sea[2] there wasn't anything to eat but rock. Rock, to
be sure, makes very good eating if you have the stomach for it, as Mr.
Lichen has. It contains sulphur, phosphorus, silica, potash, soda, iron,
and other things that plants are fond of, but ordinary plants can't get
these things out of the rock--let alone human beings and other animals;
and that's why Mr. Lichen had the first seat at the table and always
does.
[2] "The Strange Adventures of a Pebble."
On bare granite boulders in the fields, on the rocky ruins at the foot
of mountains, and even on the mountain tops themselves, on projecting
rocks far above the snow line, you find the lichens. On rock of every
kind they settle down and get to work. They never complain of the
climate--hot or cold, moist or dry. When the land goes dry they simply
knock off, and then when a little moisture is to be had they're busy
again. A little goes a long way with members of the family who live in
regions where water is scarce. Indeed, most of them get along with
hardly any moisture at all. The very hardiest of them are so small that
a whole colony looks like a mere stain upon the rock.
While lichens are generally gray--they seem to have been _born_ old,
these queer little men of the rock--you can find some that are black,
others bright yellow or cream-colored. Others are pure white or of
various rusty and leaden shades. Some are of the color of little mice.
To make out any shapes in these tiny forms, you must look very close;
and if you have a hand lens you will be surprised to find that this
fairy-land of the lichens isn't so drab as it seems to the naked eye.
For there are flower gardens--the tiny spore cups. Some of them are
vivid crimson and, standing out on a background of pure white, they're
very lovely. Some of the science people believe the colors attract the
minute insects that the lens shows wandering around in these fairy
flower gardens. But just what the insects can be there for nobody knows,
since the lichens are scattered, not by insects, but by the wind.
As a rule lichens grow only in open, exposed places, although some are
like the violets--they enjoy the shade. Some varieties grow on trees,
some on the ground, others on the bleached bones of animals in fields
and wastes and on the bones of whales cast up by the sea.
Of course the whole country was awfully wild when the continents first
came out of the sea, but that just suited Mr. Lichen, for there is one
thing he can't stand, and that is city life, with its smoke and bad air.
"Why, one can't get one's breath!" he says.
WHY THE LICHENS DISLIKE CITY LIFE
So, while you will not meet Mr. Lichen in cities--at least, until after
the people are all gone; that is to say, on ruins of cities of the
past--you will find him beautifying the ancient walls of abbeys, old
seats of learning like Oxford, and the tombstones of the cities of the
dead.
Mr. Lichen always travels light. On the surface of the lichens are what
seem to be little grains of dust, and these serve the purpose of seeds.
A puff of wind will carry away thousands of them, and so start new
colonies in lands remote.
You see, the fact that he requires so little baggage must have been a
great advantage to Mr. Lichen in those early days, when he had to
discover not only America but all the rest of the world map, spread out
so wide and far. You can just imagine how the grains of lichen dust,
the seed of the race, must have gone whirling across the world with the
winds.
But if a breath of wind would carry them away so easily, how could they
_stay_ on a rock, these tiny lichen travellers? Especially as they have
no roots? They have curious rootlike fibres which absorb food by
dissolving the rock, and this dissolved rock, hardening, holds them on.
The fibres of lichens that grow on granite actually sink into it by
dissolving the mica and forcing their way between the other kinds of
particles in the rock that they can't eat. Thus they help break it up.
As we all know, little people are great eaters in proportion to their
size, but it is said the lichens are the heartiest eaters in the world.
They eat more mineral matter than any other plant, and all plants are
eaters of minerals.
Yet, you'd wonder what they do with the food they eat--most of them grow
so slowly. A student of lichens watched one of them on the tiled roof of
his house in France--one of the kind of lichens that look like plates of
gold--and in forty years he couldn't see that it had grown a single bit,
although he measured it carefully.
HOW MR. LICHEN EATS UP STONES
But how could such feeble creatures, as they seem to be, ever eat
anything so hard as rock? Well, they couldn't if it wasn't for one
thing--they understand chemistry. At least they carry with them, or know
how to make, an acid, and it's this acid which enables them to dissolve
the rock so that they can absorb it. The acid is in their fibres--what
answer for roots. And the dissolved rock not only gives them their daily
bread, but, as I said a moment ago, holds them on. This use of acid is
their way of eating; chewing their food very fine, and mixing it with
saliva, as all of us young people are taught to do.
The first and smallest of the lichen family spread and decay into a thin
film of soil. This decay makes more acid, just as decaying leaves do
to-day--they learned it, no doubt, from the lichens--and this acid of
decay also eats into the rock and makes more soil. (You see nature, from
the start, has been helping those that help themselves, just as the old
proverb has it.) Then, after the first tiny lichens--mere grains of dust
that have just begun to feel the stir of life--come somewhat larger
lichens which can only live where there is a little soil to begin with.
These in turn die, which means a still deeper layer of soil, still more
acid of decay, and so on up to larger lichens and later more ambitious
plants. Then, on the soil made by these successive generations of
lichens, higher types of plants--plants with true roots--get a foothold.
Besides making soil themselves, the lichens help accumulate soil by
holding grains of rock broken up by their fibres and loosened by the
action of the heat and cold of day and night and change of season. These
little grains become entangled in the larger lichens and are kept, many
of them, from being washed away by the heavy rains. So held, they are in
time crumbled into soil by the action of the acids and by mixture with
the products of plant decay. To this day, go where you will, over the
whole face of the earth, and you'll find the lichens there ahead of you,
dressed in their sober suits, some gray as ashes, others brown, but some
are as yellow as gold; for even these old people like a little color
once in a while. As travellers they beat all.
"Their geographical range is more extended than that of any other
class of plants."
That's how the learned lichenologists put it. For these lichens, these
humble little brothers of our dust, that many of us never looked at
twice on the stones of the field, or the gray stumps and dead limbs in
the wood, are so interesting when you've really met them--been properly
introduced--that a whole science has grown up around them called
"lichenology." And exciting! You ought to hear the hot discussions that
lichenologists get into. You read, for instance, that such and such a
theory "was received with a storm of opposition" (as most new theories
are, by the way, particularly if they are sound).
But the tumults and the strifes of science, of politics, or of wars
don't disturb little old Mr. Lichen himself. There on his rock he'll
sit, overlooking the scenery and watching life and the seasons come and
go for 100, 200, 500 years, and more. For while they grow so slowly the
lichens make up for it by living to an extreme age.
THE LICHENS AND THE ROMAN EMPIRE
Why, do you know that during the lifetime of certain lichens that are
still hale and hearty, not only a long line of Caesars might rise,
flourish, die, and, with their clay, stop holes to keep the wind away,
as Mr. Shakespere put it, but the vast Roman Empire could and did come
into being, move across the stage with its banners and trumpets and
glittering pomp and go back to the dust again.
Some lichens, growing on the highest mountain ranges of the world, are
known to be more than 2,000 years old!
[Illustration: THE SEQUOIAS; THE SUNLIGHT AND THE SHADE
Wonderful sunlight effect, isn't it? We are here in Sequoia National
Park and those big trees are sequoias, members of the pine-tree family.]
II. THE MARCH OF THE TREES
Of course I don't mean to say it takes any 2,000 years for the average
lichen to die and turn to dust. These long-lived lichens are the
Methuselahs of their race. Most kinds die much younger, as time goes
among the lichens, and in a comparatively few years, a century say,
after their first settlement on the rock, the lichens have become soil.
All this time the heating of the rock by day and the cooling off at
night, the work of frost and the gases of the rain and the air[3] have
also helped to make more soil and by and by there is enough for lichens
of a larger growth; and mosses begin to get a foothold. These, in turn,
die and, in decaying, make acids, as did the little lichens before
them, and this acid joins hands with all the other forces to work up the
rock into soil. Presently there is enough soil to let certain
adventurers of the Weed family drop in. The picking is very thin, to be
sure, but some of these Weed people have learned to put up with almost
anything. Don't suppose, however, that all weeds are alike in this
respect. Oh, dear, no! They come into new plant communities just as the
trees do, not haphazard, but according to a certain more or less settled
order. Some of them, the adventurer type, will, it is true, settle down
and seem contented enough on land so poor that to quote the witty Lady
Townshend "you will only find here and there a single blade of grass and
two rabbits fighting for that"; while other weeds will have nothing to
do with soil that, in their opinion, is not good enough for people of
their family connections.
[3] All these things put together are called "weathering."
[Illustration: EARLY SETTLERS IN THE DESERT
Besides earning their own living under hard conditions, these sturdy
pioneers of the desert are preparing the way for plants of a higher
kind, as the next two pictures will tell you.]
It has long been known that the character of soil may be told, to a
considerable degree, by the kind of weeds that grow on it. An old
English writer pointed this out in his quaint way some 200 years ago:
"Ground which, though it bear not any extraordinary abundance of
grass yet will load itself with strong and lusty weeds, as
Hemlocks, Docks, Nettles and such like, is undoubtedly a most rich
and fruitful ground for any grain whatsoever."
But, he goes on to say:
"When you see the ground covered with Heath, Broom, Bracken, Gorse
and such like, they be most apparent signs of infinite great
barrenness. And, of these infertile places, you shall understand,
that it is the clay ground which for the most part brings forth the
Moss, the Broom, the Gorse and such like."
Wherever soil is coarse and bouldery the weeds also are of a sturdy
breed. In his long, delightful days among the mountains Muir[4] tells us
what a brave show the thistles made in this new world of soil; how royal
they looked in their purple bloom, standing up head and shoulders above
the other plants, like Saul among the people.
[4] Muir. "The Mountains of California."
[Illustration: WHAT THE DESERT PIONEERS DO FOR FUTURE GENERATIONS
Only the sturdiest kinds of shrubs and weeds, such as you see in the
desert, can earn their keep in sandy soil, always thirsty, like that on
the right. But the desert vegetation, dying and decaying--it is then
called "humus"--not only knits the soil together but absorbs moisture
and ammonia from the air and so helps grow good crops.]
HOW PLANT PEOPLE PAY THEIR TAXES
In all these plant republics each citizen must pay something into the
common treasury for its board and keep. This fund not only meets
"national expenses" during the lifetime of the ones who pay these taxes,
but it helps prepare the land for the great citizens of the future--the
trees. In another hundred years--making two hundred in all, after the
arrival of the very first lichens--low shrubs and bushes often find
spots in these new communities where the soil is thick enough for their
needs.
It is very curious how members of the plant world, growing side by side,
seek their food at different depths, and send out their roots
accordingly. It reminds one of the rigid class distinctions below stairs
in a nobleman's household where the chef has his meals in his own
private apartment, the kitchen maids in their quarters, the chauffeurs,
footman, under butler, and pantry boys in the servants' hall.
[Illustration: THE LEADERS OF THE GRAND MARCH]
But most striking, it has always seemed to me, is the settled order in
which trees march into the land. Why shouldn't the oaks come before the
maples? Or the maples before the beeches? Or the beeches before the
pines? Why is it that, with the exception of a straggler here and there,
the first trees to climb the stony mountainsides are the pines? Then
close behind come such trees as the poplars, and along the streams
below, the willows. Still farther down the valley are the beeches;
farther still the maples, and last of all the oaks.
So it is they advance in a certain regular way, each in its own place in
the ranks. At first it seems as strange as the coming of Birnam wood to
Dunsinane that gave poor Macbeth such a turn that time. But, after all,
the explanation is quite simple and no doubt you have guessed it
already.
The reason such trees as the pines, poplars, and willows come first is
that the seeds are so light they are easily carried by the winds and so
reach new soil ahead of other trees with winged seeds like the beeches
and the maples; for, although these seeds also travel on the wind, they
are much larger than the winged seeds of the pine and they travel much
more slowly and for shorter distances.
Moreover, at the end of their first journey, having once fallen to the
ground, they are apt to stay. Then there is no further advance, so far
as these particular seeds are concerned, until trees have sprung from
them and they, in turn, bear seeds. In the case of very light seeds,
like those of the pines, the wind not only carries them far beyond the
comparatively slow and heavy march of the beech and the maple, but if
they fall on rock with little or no soil the next wind picks them up and
carries them farther, so that they may strike some other spot where
there is soil and perhaps a little network of grass and weeds to secure
them until they can take root and so hold their own. It is not only a
great advantage to the pine seeds to be so small, so far as getting
ahead of other trees is concerned, but it is an advantage in another
way. Because they are so small they require comparatively little soil to
start with, are more easily covered up, and so they soon begin to
sprout. The very winds that carry them up among the mountain rocks are
quite likely to cover them with enough dust to start on, and I myself
have helped raise many a giant of the mountain forests in this way. It
is really wonderful how little soil a pine-tree can get along with; if,
say, its fortunes are cast on some mass of mountain rock. Somehow it
manages to get a living among the cracks and at the same time to hold
its own in the bitter struggle with the winds.
"The pine trees," says Muir, "march up the sun-warmed moraines in long
hopeful files, taking the ground and establishing themselves as soon as
it is ready for them."
[Illustration: _From the painting by Rousseau in the Metropolitan Museum
of Art._
THE EDGE OF THE WOODS
Last of all come tramping along the sturdy old oaks.]
Last of all come tramping along the sturdy old oaks and the nut-bearing
trees. Their seeds are so heavy they get little help from the winds, and
then only in the most violent storms. They must advance very slowly
indeed, with occasional help from absent-minded squirrels who carry away
and bury nuts and acorns and then forget where they put them.
[Illustration: HOW SQUIRRELS HELP OAKS TO MARCH
Sometimes they bury acorns and forget just where. When frightened they
often drop them and run away.]
ROUGH CITIZENS AMONG THE PIONEERS
The beginnings of a forest are stunted because the soil is thin.
Moreover, the company in which the trees find themselves is very
miscellaneous, like the population of all pioneer communities--weeds,
grasses, briers, shrubs. High up on a mountainside you can find all
these types of vegetation. Pines growing clear to the snow line; farther
down the mountain, in crannies, sumach and elder bushes with field
daisies and goldenrod scattered among them; while on the barren rocks
are the lichens and the mosses.
Not only do the citizens of the plant world follow a certain fixed order
in coming into new regions, but also in giving place to one another. All
plants of a higher order can live only on the remains of those of a
lower, and it is most interesting to note the process by which each
lower form comes, does its work, passes on, and is replaced by a
superior type. The shrubs, which can only grow after the weeds and
grasses have made enough soil for them, at length shade out these
smaller pioneers. Haven't you often noticed, when picnicing in deep
woods, that the grasses and flowers are to be found only in the sunny
spaces, where there are no trees?
But these thickets themselves, after a while, disappear, and pines take
their places. I am speaking now of the growth of forests, where the
soil-making has so far advanced that forests are possible. The thickets,
with their good soil and the shade which keeps it damp, are just the
places for the pine seeds brought in by the wind to get a foothold and
sprout up. When they grow into big trees they gather with their high
branches so much of the sunshine for themselves that little of it gets
through to the shrubs below, so these shrubs disappear, surviving only
in the sunny open spaces or along the borders of the wood.
But now notice what happens to the pines. When the trees become larger,
the young pines that spring up beneath their shade can't get enough
sunshine, so, as the big trees grow old and die, there are fewer and
fewer young pines to take their places. Now comes the turn of the
spruces. For spruces require more and better soil than the pines and
they don't mind a reasonable amount of shade. So, as the woods grow
thicker and shadier, the pines gradually disappear and the spruces take
their places.
At first, in the reign of the spruces, some of the old residents begin
to come back. A spruce forest, not being so dense in the beginning as a
pine forest, lets in a good deal of sunlight, and you'll find scattered
through its aisles and byways gentians, bluebells, daisies, goldenrod.
In course of time, however, the leaves and branches of the spruces
become so thick that hardly a sunbeam can get through and you have a
forest where noontime looks like twilight; a forest of deep shade and
silence with its thick carpet of brown needles, and where all the shrubs
and grasses and flowers have disappeared, except in the open spaces. It
was in such a forest and in one of these sunny glades, no doubt, that
the knight the little girl tells of in Tennyson:
"... while he past the dim lit woods
Himself beheld three spirits mad with joy
Come dashing down on a tall wayside flower
That shook beneath them as the thistle shakes
When three gray linnets wrangle for the seed."
HOW NATURE RESTORES ABANDONED FARMS
So it is that new lands pass from barren rock to forest, and deep rich
soil, and so it is that worn-out soils, the result of reckless farming
are finally restored. Hardly any soil is too poor for some kind of a
weed. These weeds springing up, die and make soil that better kinds of
weeds can use. Later come a few woody plants. In the course of fifteen
or twenty years the soil is deep enough to support trees; and in fifty
years there is a young forest. At the end of a century fine timber can
be cut, the land cleared, and the old place may be as good as new.
But it's a long time to wait! It's a much better plan to take care of
the land in the first place.
HIDE AND SEEK IN THE LIBRARY
One of the strangest things about Mr. Lichen, as you will see by
looking up the subject in any botany or encyclopaedia, is that he is
really _two_ people--two different plants that have grown into
partnership; and that one of the partners supplies water for the
firm while the other furnishes the food.
The part of "him" that supplies the food is green, or blue-green,
and that is why it is able to do this. This idea that Mr. Lichen is
really two people was one of those that was "received with a storm
of opposition," but certain lichenologists actually took two
different kinds of plants, put them together and _made_ a lichen
themselves, as you will see when you look the matter up.
As to just who among these two kinds of plants shall go into
partnership--that usually depends on chance and the winds; although
in the case of some lichens, the parents determine upon these
partnerships, just as they often do in human relations.
If you want to continue this interesting study and become Learned
Lichenologists, you will be interested to know that there are a lot
of things to be learned, including not only no end of delightful
names, such as _Endocarpon_, _Collema_, _Pertusaria_, not to speak
of _Xanthoria parietina_, and loads of others, but there are still
things unknown that _you_ may be able some day to find out. For
instance, while they know that the two kinds of vegetation that
together make a lichen, feed and water each other, it's not known
exactly _how_ they do it; although the "Britannica" article has a
picture showing the two partners in the very act of going into
partnership. The article in the "Americana" shows some striking
forms of lichens, and how nature from these very dawnings of life
begins to dream of beauty. You will be surprised at the forms shown
in the "Americana," they are either so graceful, symmetrical, or
picturesque. One of them looks like a very elaborate helmet
decoration, or plume of a knight.
This article also tells what an incredible number of species of
lichens there are--enough to make quite a good-sized town, if they
were all real people.
It also tells why the orange and yellow lichens take to the shady
side of the rock; and something about how the lichens get those
remarkable decorations and sculpturings, and what the weather has
to do with it.
There you will also get a probable explanation of the fact that the
manna which the Israelites found on the ground in the morning
appeared so suddenly.
In the article in the "International" you will find another picture
of how the two partners--the fungus and the alga--make the lichen,
and you will learn that Mr. Lichen's name, like Mr. Lichen himself,
is centuries old; being the very name given him by the Greeks, and
afterward by the Romans.
In the "Country Life Reader" there is an article on the soil that
has a very close relationship to the subject of the lichens and
their work. It tells, among other things, about the value of
humus--decayed leaves, grass, etc.--to the soil. It was the
lichens, you know, who _started_ the humus-making business.
The article in the reader on "Planting Time," by L. H. Bailey,
expresses the wonder we must all feel when we stop to think about
it, at the magic work of the soil in changing a little speck of a
seed into a plant.