The Adventures of a Grain of Dust

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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.

Chapter II

(February)

Behold a strange monster our wonder engages! If dolphin or lizard your wit may defy. Some thirty feet long, on the shore of Lyme-Regis With a saw for a jaw and a big staring eye. A fish or a lizard? An Ichthyosaurus, With a big goggle-eye and a very small brain, And paddles like mill-wheels in chattering chorus Smiting tremendous the dread-sounding main.

--_Professor Blackie._

Some Early Settlers And Their Bones

But a farm where nothing but plants grow isn't much of a farm. Every good farmer knows that nowadays, and so he stocks his place with horses and cows and chickens and things. Mother Nature understood this principle from the beginning, and the plants and animals on her farm have always got on well together.

For one thing the plant and the animal each help the other to get its breath. That is to say, plants, when they take in the air, keep most of the carbon there is in it and give back most of the oxygen, which is just what the animal world wants; while the animals, when they breathe, keep most of the oxygen and give back most of the carbon--just the thing that plants grow on.

But the service of the animals to the plants is very important after they have stopped breathing altogether; since their flesh and bones, like the dead bodies of the plants, go back to enrich their common dust. The bones and bodies and shells of members of the animal kingdom, however, are far richer food for soils than is dead vegetation. The shell creatures of the sea to which we owe our wonderfully fertile limestone soils are--many of them--so small that you can only make them out with a microscope; while certain other contributors to our food-supply were so big that one of them, walking down a country road, would almost fill the road from fence to fence.

I. Mr. Dinosaur And His Neighbors

A Strange Face In The Meadow

Now let's take a look at some of these big fellows. How would you like to have such a creature as the one at the right of this page come ambling up to meet you at the meadow gate of an evening when you went to milk the cows? Yet more than likely either this gentle animal, or some of his kin, browsed over the very field where now the cattle pasture, for he, too, was a grass-eater, and with an appetite most hearty. If you kept him in a barn his stall would have to be eighty feet long, and it would be necessary to fill his rack with a ton of fodder every third day. But, assuming there was a market for him in the shape of steaks and roasts, you would be well repaid; for, in prime condition, he weighed twenty tons.

[Illustration: IN THE LAND OF HIS FATHERS]

These monsters who ate grass, and other monsters who ate them, and still other monsters who lived in the sea, appeared comparatively late in the life of the world.

[Illustration: NO WONDER HE NEVER WORRIED!

Quite aside from the fact that he had so little brain to worry with, it seems highly improbable that the Stegosaurus ever felt any apprehension about attacks from the rear, in the frequent military operations which distinguished the times in which he lived. In addition to the horny plates down his back he had those horny spines which were swung by a tail some ten feet long.]

Tons And Tons Of Ancient Bones

It is only about 15,000,000 years ago, for example, that the biggest of them all, the Dinosaurs, lived, while the earth itself is now supposed to be some 100,000,000 years old. Their numbers were enormous, and it is probable there is not an acre of ground from the Atlantic to the Pacific, and from Alaska to the tip end of South America that has not been fertilized by their bones. In fact, of certain species I have found the bones scattered all the way from Oregon to Patagonia; so this must have been their pasture.

They were not only all over the land, but in the lakes and in the great sea that once extended right through North America from the Gulf of Mexico to the Arctic Ocean. And they were along the shores of the sea and in the swamps. The bones of the ancestors of the whale were found in such quantities in some of the Southern States that they were used to build fences until it was found they were much more valuable to enrich the fields themselves.

[Illustration: THE HEAD OF HESPERORNIS

"Then there was a great toothed, diving creature with wings. They've named him the Hesperornis, which means 'western bird,' because the fossils of the best-known species were found in the chalk-beds of Kansas."]

In the great American inland sea of those days swam one kind of fierce fish-lizard that took such big bites he had to have a hinge in his jaw. Because of this hinge he could open his mouth wider without putting anything out of place, don't you see? He was called the Mesosaur. But he never bit the Archelon, who was in his crowd, because he couldn't. The Archelon was the king of turtles, and, like all the turtle family, wore heavy armor. He was over twelve feet long. And sharks--no end of them! A shark at his best is bad enough, but the sharks of those days were almost too terrible to think about. Such jaws! And teeth like railroad spikes! Then there was a great toothed diving creature with wings. They've named him the "Hesperornis," which means "western bird." He was given the name because the fossils of the best-known species were found in the chalk-beds of Kansas.

[Illustration: GREATEST OF ANCIENT FLYING MACHINES

Mr. Pterodactyl, on his way to dinner, looked like this. He was the largest of all flying-machines before the days of the Wright brothers. He would have measured--if there had been anybody to measure him--twenty feet across the wings! Like the Hesperornis, he always dined on fish.]

Over the waters flew another bird-like, fish-like, bat-like thing called the Pterodactyl. Look at his picture and you will see how he got his nickname. It means "finger-toe." He was the largest of all flying-machines until the days of the Wright brothers. It was over twenty feet across his wings, from tip to tip; and, like the Hesperornis, he always had fish for dinner.

[Illustration: A BIG "LITTLE FINGER" AND WHAT IT WAS FOR

Mr. Pterodactyl means "finger toe." What is our little finger was the longest of his five digits. It helped support and operate that big bat-like wing extending from his arms to his toes.]

The Earliest Rulers Of The Sea

The first monsters, like the first of almost everything else, including the land itself, were in the sea.[5] For a time giant fish, armor-plated like a man-of-war, and with awful appetites, just about ran everything. Then came the reign of the sharks. Some of them had jaws that opened to the height of a door--six feet or over. Next in succession, as rulers of the sea, were the fish-lizards, of whom that hinge-jawed Mesosaur was one. Of another of these fish-lizards a famous teacher of Edinburgh University, Professor Blackie, wrote that funny verse at the head of this chapter. The bones of this particular specimen were found sticking out of a cliff at Lyme-Regis, a popular watering-place in the English Channel, by a pretty English girl who was strolling along the beach.

[5] "The Strange Adventures of a Pebble."

[Illustration: A FAMILY PARTY

The imagination of the artist enables us to picture this family party--Mrs. Ichthyosaurus and her children out for a stroll in prehistoric waters.]

The Ichthyosaurus, as Professor Blackie says in his verse, was some thirty feet long, with a comparatively large head--like an alligator's--set close to his body. Another fish-lizard, well and unfavorably known by his neighbors of the sea, was the Plesiosaurus. Instead of fins he had big paddles resembling those of the seal. He was a kind of side-wheeler, like the Mississippi River steamboats, and he could go like everything! His neck was long and he darted after the smaller creatures he lived on.

Reign Of The Lizard Family

But these queer fish seem to have just been getting ready to land; for, by being lizards, they after a while managed it. A lizard, you know, belongs to the reptile family, and out of these sea reptiles there grew, in course of time, reptiles which lived, not in the sea but in the swamps along the sea. These reptiles were the Dinosaurs, and they are related to the Minosaurs and the Ichthyosaurus, and the rest of the Saurs, as you can see by the family name; for "saur" means lizard. Dinosaur means "terrible lizard." Don't you think he looks it?

Although some of these Dinosaurs were no larger than chickens, others were by far the largest creatures that ever were, on sea or land. Many of the biggest lived on grass, just like an old cow, while the flesh-eating Dinosaurs lived on them. Some of these Dinosaurs went on all fours, while others ran about on their hind legs, and when they stood still, propped themselves up on their big, thick tails as do kangaroos. The Camptosaurus, one of whose favorite resorts was the land that is now Wyoming, was thirty feet long. Another called the Brontosaurus, was sixty feet long. The Atlantosaurus, one of the pioneers of Colorado, measured eighty feet from the end of his nose to the end of his tail, and all of them were built in proportion. The Stegosaurus, also an early settler in Wyoming, had huge bony plates, like ploughshares, sticking out all along his back from the nape of his neck to the end of his tail. He seems to have gone about looking quite ugly and humpbacked, as our old cat does when she has words with the dog.

After the swamps dried up and the lizards could no longer make a living, came the reign of the mammals; including the Mastodons and the Mammoths, marching in countless herds, trumpeting through the forests.

How Some Monsters Ploughed The Field

But besides what they did in the way of fertilizing the land with their flesh and bones some of the mammals did a good deal of ploughing. Among these early ploughmen were the Mastodons and the Mammoths, and another elephant-like creature with two tusks, that he wore, not after the fashion among elephants to-day, but curving down from his chin, somewhat like Uncle Sam's goatee. He used these tusks, it is supposed, not only for self-defense, but for grubbing up roots which he ate. If so, they must have been about as good ploughs as those crooked sticks that were used by the early farmers among men, and that are still in use among primitive peoples.

The Elephant Family As Ploughmen

What makes it more likely that the creature with the down-curving tusks stirred the soil with them is that his cousins, the elephants of to-day, are themselves great ploughmen. Elephants feed, not only on grass and the tender shoots of trees, but on bulbs buried in the soil, which they hunt out by their fine sense of smell. In digging these bulbs they turn up whole acres of ground. Elephants also do a great deal of ploughing by uprooting trees so as to make it more convenient to get at their tender tops. Sir Samuel Baker, the explorer, says the work done by a herd of elephants in a mimosa forest in this way is very great and that trees over four feet in circumference are uprooted. In the case of the biggest trees several elephants work together, some pulling the tree with their trunks, while others dig under the roots with their tusks. To be sure, the mimosa-trees have no tap roots, but tearing them out of the ground is no small job, nevertheless. It takes strength and it takes engineering.

Another early ploughman was a bird, the Moa. The Moa had no wings, but his muscular legs were simply enormous, and so were his feet. New Zealand seems to have been the headquarters of the Moas. There used to be loads of them as shown by the huge deposits of their bones. They are supposed to have been killed in countless numbers during the Ice Ages in the Southern Hemisphere; for there were Ice Ages in the Southern as well as the Northern Hemisphere. In one great morass in New Zealand abounding in warm springs, bones of the Moas were found in such countless numbers, layer upon layer, that it is thought the big birds gathered at these springs to keep warm during those great freezes.

The Millstones Of The Moas

Besides the work they did with feet and bills you may imagine how much nice fresh stone the Moas must have ground up in their crops during the millions of years they existed. It was a regular mill--the gizzard of a Moa--full of pebbles as big as hickory nuts. Scattered about the springs where their bones are found are little heaps of these pebbles, each the contents of a gizzard. Like miniature tumuli, they mark the spots where the bodies of the Moas returned to dust.

Perhaps some of those flesh-eating Dinosaurs did a little ploughing once in a while, too; for one theory is that those ridiculous little arms were used for scratching out a nest for the eggs, just as the crocodiles and the alligators and the turtles dig nests for their eggs to-day. For all these animals, as did the Dinosaurs, belong to the reptile family, and show the family trait of digging out nests for their eggs.

[Illustration: A PUZZLE PAGE FROM THE GREAT STONE BOOK

Talk about your cut-out puzzles! Here is a specimen of the kind of puzzle Nature and the course of things in the darkest ages of world history have cut out for the paleontologists. It is a find of ancient bones in the asphalt deposits near Los Angeles.]

Although the Dinosaurs roamed the swamps and lowlands of all the ancient world, their favorite resort was the territory now occupied by our Western States--judging from the quantities of bones they left--while that old Mediterranean Sea of ours was full of their kin, the sea-lizards. Professor Marsh, of Yale, who was among the first explorers of the graves of these monarchs of the past, says that one day, while riding through a valley in the Rocky Mountains, he saw the bones of no less than seven sea-lizards staring at him from the cliffs. Yet, only here and there by the wearing through of the rocks by flowing streams has nature opened up these vast mausoleums, the mountains and the cliffs. What enormous quantities of bones, then, must still be buried there, what tons and tons must have given their lime and phosphate to the soil. So you see this story of old bones, even from a farming standpoint, is no light matter.

[Illustration: HOW THE WISE MEN ANSWER THE PUZZLES

By their marvellous skill and their knowledge of the mechanics of monster anatomy the paleontologists fit one bone fragment to another, supply the missing parts in artificial material, and behold! the monsters take their places in the long procession of the ages. There has been nothing equal to it since the vision of the prophet in the Valley of Dry Bones. (Ezekiel 37:1-10.)]

II. How The Monsters Died And Returned To Dust

"But you said these monsters lived in the sea and in swamps. Then how, in the name of common sense, did their bones get up into the mountains?"

When The Inland Sea Went Dry

Well, it's like this: As I said a while back, in the days of the monster fish and the monster lizards, there was a great sea reaching clear from the Gulf of Mexico to the Arctic Ocean, and with swamps along the borders extending far into lands that afterward became the Rocky Mountains. When the land began to rise, due to the shrinking of the earth--a thing that has been going on ever since the earth was born--the sea and the swamps went dry, and far to the west the land wrinkled up into the Rocky Mountains. In these layers of rock that made the mountains were the bones of the monsters that had died when the rocks were still mud, in the swamps and along the borders of the inland sea.

Not only did the land under the western portion of the sea slowly rise until the waters were completely closed in on the west, and the sea thus made that much narrower, but the rise of the land on the south cut off connection with the great salt ocean which surrounds the continents to-day. So the salt-water fish, for lack of salt water, died, and with them the monsters like the Ichthyosaurus that lived on the salt-water fish that lived in this salt sea.

But it wasn't alone that the seas grew narrower and more shallow because of the elevation of the lands. The mountains rising in the west, cut off the rain-laden winds which blew from the Pacific in those days just as they do now. Thus the seas dried up so much the faster. But first, before the sea went entirely dry, its place was taken by the lakes and swamps into which it shrivelled up. Low, swampy land is just what reptiles like, so this was their Golden Age, just as the previous time of the wide, deep sea was the Golden Age of the big fish and the fish-lizards.

Then, as the land still rose and the climate grew dryer, the reptiles passed away, and in came the mammal family, to which the cows and the horses and the cats and the kittens, and all the rest of us, belong.

[Illustration: THE TIGER WITH THE SABRE TEETH

Tigers like this lived ages ago in both the Old World and the New. They had canine teeth, curved like a sabre, in the upper jaw.]

Too Much Brawn, Too Little Brain

Of course, even where they didn't die with their boots on, so to speak, as so many of them did in those lawless days, there came a time for each monster, in the order of nature, when he drew his last breath. But what seems so strange is that all these monsters--the biggest and strongest of them--entirely disappeared and left no descendants![6] The whole of the mystery has not been unravelled yet, even by the wise men of science, but still they have learned a good deal. For one thing, they know that most of the reptiles and the fish-lizards disappeared because so much of the land where they lived went dry. They had to get a new boarding-place, and there wasn't any to get! Another thing was that these big fellows, although they _were_ so big, and got along finely while everything was just so, had so little brain they couldn't change their habits to meet new conditions, as our closer and cleverer cousins, the mammals, did. Why, do you know that one of these monsters, who was twenty-five feet long if he was an inch, and twelve feet high, had a brain no bigger than a man's fist? All the monsters of those days were like that--tons of bone and muscle, but a very small supply of brains.

[6] That is to say, no descendants worthy of them. It is now thought some of the modern reptiles may be degenerate descendants of the big reptiles of old.

So when things went against them, they just had to give up, and, like a queer dream, they faded away. But their history makes one of the most interesting chapters in the whole wonderful story of the dust.

Of all the live stock that have fed on the great world-farm and helped enrich it with their bones, these animals were surely the strangest that ever were seen!

Hide And Seek In The Library

"But since these monsters passed away many millions of years ago, and all that is usually found is a piece of them here and there, how do the men of science know so much about them--how they looked, and how they ate, and how they treated one another?"

That's a good question. It _does_ seem strange. Why, to hear them talk, you'd suppose these men, learned in ancient bones, had actually _met_ the monsters! And, speaking of meeting them, I must tell you a little story. It's a good story and it will answer your question.

Baron Cuvier, one of the most famous of the paleontologists, awoke from a deep sleep to see standing by his bed a strange, hairy creature with horns and hoofs. And it said:

"Cuvier! Cuvier! I have come to eat you!" But the baron, taking in the form of the monster at a glance, only laughed.

"Horns and hoofs? You can't. You're a grain-eater!"

See the point? The baron argued that because the monster had horns and hoofs he must be a grain-eater; for all creatures with both horns and hoofs are grain-eaters. This particular creature, to be sure, was an eater of both meat and grain--being one of Cuvier's students who was trying to play a trick on him. But the principle holds good. The scientists, _knowing_ one thing, _infer_ another. Because animals with both horns and hoofs eat no meat Cuvier knew his visitor couldn't eat _him_, even if he'd been real and not just made up.

For another instance, take our queer old friend that Professor Blackie wrote the funny rhyme about--the Ichthyosaurus "with a saw for a jaw and a big staring eye." The scientists figure, just from looking into the hollow socket where the eye used to be, that he could see at night like a cat--and right through muddy water, too; that he spent most of his time in shallows near the shore; that it didn't make any difference to him whether a fish was near or far, provided it wasn't too far, of course, for he could see it and catch it, just the same. They also said--these learned men, after peering into the dark hollow where that remarkable eye used to be--that Mr. Ichthyosaurus spent a great deal of time diving and a great deal of time with his homely face just above the surface of the water.

Why they could reason all this from a hollow eye socket and some bony, flexible plates around the outer edge of it, you will see by referring to such books as "Animals of the Past," by F. A. Lucas, director of the American Museum of Natural History; "Creatures of Other Days" and "Extinct Monsters," by Hutchinson; "Extinct Animals," by Lankester; "Mighty Animals," by Mix; the chapter "When the World was Young," in Lang's "Red Book of Animal Stories," and "Restoring Prehistoric Monsters" in "Uncle Sam, Wonder Worker," by Du Puy.

Here are some more conclusions they draw from certain facts. See how near you can come to reasoning them out for yourself before looking them up in the books that tell.

Why it is supposed the Dinosaurs swam like Crocodiles. (Look at the picture of Mr. I., and pay _particular_ attention to his tail.)

Why it is they say that the sea-lizards with long necks must have had small heads.

Why it is argued that because the Mesosaurus had a hinge in his jaw he must have had a big, loose, baggy throat.

"Keeping Up the Soil," in "The Country Life Reader," deals with the subject of the use of fertilizers on the farm--how easy it is to waste them, how easy it is to save them, and how important it is that they should be saved; while the article on "Acid Soils" tells how the lime in the bones of the monsters has helped keep the soil from getting "sour stomach," and also how they unlocked the potash and phosphorus in the soil so that the plants could get at them.

[Illustration: FERTILE FIELDS THAT RODE ON THE WIND

The winds that now help grow the corn and wheat on these broad fields by carrying the pollen from one plant to another, also brought the soil on which they grew. These are the loess plains of Nebraska. There are 42,000 acres of them.]

Chapter III

(March)

... the busy winds That kept no intervals of rest.

--_Wordsworth._

Except wind stands as never it stood 'Tis an ill wind turns none to good.

--_Tusser._

The Winds And The World'S Work

That saying "idle as the winds" must have started in the days when they didn't know; for if ever there was a busy people, it's the Winds.

Not only do they help plant the trees of the forest, sow the fields with grass and flowers, and water them with rain, but they make and carry soil all over the world. And, like everything else in Nature, they have a sense of beauty and the picturesque. Rock, for example, weathered away into dust by the help of the winds, as it is, takes on all sorts of picturesque shapes. And, of course, the winds love music; everybody knows that. Before we get through with this chapter we're going to end a happy day outdoors with a grand musical festival in the forest, with light refreshments--spice-laden winds from the sea. There'll be nobody there but the trees and the winds and John Muir and us; all nice people.

I. Such Clouds Of Dust!

March leads the procession of the dusty months because the warming up of the land, as the sun advances from the south, brings the colder and heavier winds down from the north. These winds seem to have a wrestling match with the southern winds and with each other, and among them they kick up a tremendous dust, because there's so much of it lying around loose; for the snows have gone, and the rainy season hasn't begun, and the fields are bare.

About The Dust We Get In Our Eyes

Most people think these March winds a great nuisance because some of us dust grains are apt to get into their eyes; but dust in the eye is only the right thing in the wrong place. Just think of the amount of dust going about in March that _doesn't_ get into your eye; and how nice and fine it is, and how mixed with all the magic stuff of different kinds of soil, thus brought together from everywhere.

An English writer on farming says he thinks the fact that English farms have done their work so well for so many centuries is due, in no small degree, to the March winds that have brought us world-travelled dust grains from other parts of the globe.

And the wind is a good friend to the good farmer, but no friend to the poor one; for it carries away dust all nicely ground from the fields of the farmer who doesn't protect his soil and carries it to farmers who have wood lots and good pastures and winter wheat, and leaves it there; for woods and pastures and sown fields hold the soil they have, as well as the fresh, new soil the winds bring to them.

Most of the fine prairie soils in our Western States owe not a little of their richness to wind-borne dust. In western Missouri, southwestern Iowa, and southeastern Nebraska are deep deposits of yellowish-brown soil, the gift of the winds. And, my, what apples it raises! It is in this soil that many of the best apple orchards of these States are located. And now, of course, the apple-growers see to it that this soil stays at home.

But there's another kind of dust that deserves special mention, and that's the kind of dust that comes from volcanoes. Volcanoes make a very valuable kind of soil material, often called "volcanic ash." It isn't ashes, really. It's the very fine dust made by the explosion of the steam in the rocks thrown out by the volcano. The pores of the rocks, deep-buried in the earth, are filled with water, and when these rocks get into a volcanic explosion, this water turns to steam, and the steam not only blows out through the crater of the volcano, but the rocks themselves are blown to dust. This dust the winds catch and distribute far and wide. Sometimes the dust of a volcanic explosion is carried around the world. In the eruption of Krakatoa, in 1883, its dust was carried around the earth, not once but many times. The progress of this dust was recorded by the brilliant sunsets it caused. It is probable that every place on the earth has dust brought by the wind from every other place. So you see if you happen to be a grain of dust yourself, and keep your eyes and ears open, you can learn a lot, as I did, just from the other little dust people you meet.

The Winds And Volcanoes

But that isn't all of this business--this partnership--between the volcanoes and the winds. Did anybody ever tell you how the volcanoes help the winds to help the plants to get their breath? It's curious. And more than that, it's so important--this part of the work--that if it weren't carried on in just the way it is, we'd all of us--all the living world, plants and animals--soon mingle our dust with that of the early settlers we read about in the last chapter. In other words, all the _plant_ world would die for lack of fresh air and all the _animal_ world would die for lack of fresh vegetables. So they say!

According to that fine system--the breath exchange between the people of the plant and animal kingdoms--the plants breathe in the carbon gas that the animals breathe out; you remember about that. But the amount of carbon gas in the air is never very large, and if there were no other supply to draw on except the breath of animals and the release of this same gas when the plants themselves decay, we'd very soon run out.

Now this needed additional supply comes from the volcanoes. Every time a volcano goes off--and they're always going off somewhere along the world's great firing-line--it throws out great quantities of this gas, and this also the winds distribute widely and mix through the atmosphere.

And another thing: This carbon in the air helps crumble up the rocks already made, and it enters into the manufacture of the limestone in the rock mills of the sea. This limestone will make just as rich soil for the farmers of the future as the limestones of other ages have made for the famous Blue-Grass region of Kentucky, for example.

All of which only goes to show how first unpleasant impressions about people and things are often wrong. A "dusty March day," you see, isn't just a dusty March day. It's quite an affair!

II. The Dust Mills Of The Wind

But wind is not alone a carrier for other dust-makers; it has dust mills of its own. The greatest of these mills are away off among the mountains and in desert lands, but after making it in these distant factories the winds carry much of this fresh new soil material to lands of orchard and pasture and growing grain.

Not long ago two of the professors at the University of Wisconsin found a good illustration of what an immense amount of soil is distributed in this way, and what long distances it travels. Among the weather freaks of a March day was a fall of colored snow that, it was found, covered an area of 100,000 square miles, probably more. The color on the snow was made by dust blown clear from the dry plains of the Southwestern States, a thousand miles away. The whole of this dust amounted to at least a million tons; and may even have amounted to hundreds of millions of tons, so the professors think.

[Illustration: TYPES OF NATURE'S SCREW PROPELLERS

You can see for yourself (from the picture on the left) that long before man ever thought of driving his ships through the water with screw propellers or pulling his flying machines through the air by the whirligigs on the end of their noses, some flying seeds, such as those of the ash here, had screw propellers of their own. And do you know that Nature also employs the propeller principle, not only in the operation of the wings of birds but in the wing feathers themselves? The two pictures on the right show the action of the wing and the wing feathers when a bird is in flight.]

Little Millstones In Big Business

For grinding rocks to get out ore, or for making cement in cement mills, men use big machines, somewhat on the style of a coffee-mill. These machines are called "crushers." The winds, in their enormous business of soil-grinding, however, stick to the idea you see so much in Nature, that of using _little_ things to do _big_ tasks; as in digging canyons and river beds, and spreading out vast alluvial plains by using raindrops made up into rivers; in working the wonders of the Ice Ages with snowflakes; and building the bones and bodies of those big early settlers, and of all animal life, and the giant trees of the forest out of little cells. For, what do you suppose the winds take for millstones in grinding down the mountains into dust? Little grains of sand!

And with the help of the sun and Jack Frost it makes these fairy millstones for itself. The outside of a big rock grows bigger under the warm sun, in the daytime, and then when the sun goes down and the rock cools off it shrinks, and this spreading and shrinking movement keeps cracking up and chipping off pieces of rock of various sizes. Up on the mountain tops, among the peaks, the change of temperature between night and day is very great, and even in midsummer you can always hear a rattling of stones at sunrise. The heat of the rising sun warms and expands the rock, and so loosens the pieces that Jack Frost has pried off with his ice wedges during the night.

Then also during periods of alternate freezing and thawing in Spring and Fall, the rock is slivered up. These changes in the weather as between one day and another are due to the winds. In January and February, for example, thaws and freezes are common. When the winds blow from the south, the snow melts, water runs into cracks in the rock and fills their pores; then a shift of the winds to the north, a freeze, and the water in the crevices and the pores turns to ice, expands, and breaks off more rock.

And what muscles Jack has! Freezing water exerts a pressure of 138 tons to the square foot; so there's no holding out against him once he gets his ice wedges in a good crack. He sends huge blocks tumbling down the mountainside. The larger blocks, striking against one another, break off smaller fragments. The smallest fragments the wind seizes. Others are washed down by the rains. The largest, carried away by mountain torrents, bump together as they thunder along, and so break off more fragments and grind them so small that the wind can pick them up along the banks when the torrents shrink, or in their beds when these sudden streams go dry.

Running Water And The Winds

In changing rock into soil, running water and the winds each have an advantage over the other. Water weighs a great deal more than air--over 800 times as much--and so grinds faster with its tools of pebbles and sand. The winds, on the other hand, get over a great deal more territory, and they, like the lichens, understand chemistry. Two of the gases they always carry right with them--carbon dioxide and oxygen--help decay the rocks.

As I said, the winds do most work in dry and desert regions, but when you remember that over a fifth of the globe is just that--dry as a bone most of the time--you see this is a great field. It has been so from the beginning, for it is thought probable that there was always about the same proportion of desert lands. Night and day the winds have been busy through all these ages. Dust is carried up by ascending air currents. Then the same force that keeps the earth in its orbit--gravity--pulls down on a grain of dust. But its fall is checked by the friction of the air. You see there's a lot of mechanics involved in moving a grain of dust; and Nature goes about it as if it were the most serious business in the world; handles every grain as if the future of the universe depended on it. In the case of sand or coarse dust, unless the winds are very strong, gravity soon gets the best of it, and down the dust grain comes to the ground again; then up with another current, then down again--carried far by stiff breezes, only a short distance by puffs--a kind of hop, skip, and jump. But fine dust getting a good lift into the upper currents at the start may stay in the air for weeks.

[Illustration: _Courtesy of The Dunham Company._

To Keep Moisture And Soil At Home

In the broad fields of the West, where "dry-farming" is practised, they have these huge machines. They are called "Cultipackers." They are cultivators with big, broad-brimmed wheels that pack the surface of the soil after the blades of the cultivator have stirred it. This not only prevents the moisture in the soil from evaporating as fast as it would otherwise do, but keeps the winds from carrying away the soil itself.]

In very wild wind-storms it has been figured out that there may be as much as 126,000 tons of dust per cubic mile; several good farms in the air at once, over every square mile of the earth below!

III. The Storm Ploughs Of The Wind

Two Kinds Of Wooden Ploughs

They use wooden ploughs, these winds, just as primitive man did, and as primitive peoples do now; but not quite in the same way, and the ploughing they do is much better. For man's wooden plough is a crooked stick made from the branches of a tree while the winds use the whole tree--roots and all, and both on mountainsides and on level lands the amount of ploughing they do is immense.

Almost all forests are liable to occasional hurricanes which lay the trees over thousands of acres in one immense swath. A large number of these trees, owing to their strong trunks, do not break off but uproot, lifting great sheets of earth. Soon, by the action of its own weight and the elements, this soil falls back. The depth to which this natural ploughing is done depends, of course, on the character of the tree, but as it is the older and larger trees that are most likely to be overturned, since they spread more surface to the wind, the ploughing is much deeper than men do with ordinary ploughs.

The result is that new unused soil is constantly being brought to the surface; and not only this, but air is introduced into the soil far below the point reached by ordinary ploughing. The soil needs air just as we do; for the air hurries the decay of the soil and its preparation for the uses of the plant. The immediate purpose of ploughing is to loosen the soil so that the roots of the plants can get their food and air more easily. It also helps to keep the fields fertile by exposing the lower soil to more rapid decay.

But here's the trouble: While the ordinary plough introduces air into the soil for a few inches from the surface, the subsoil, which is very important to the prosperity of the plant, is practically left out of it, so far as getting needed fresh air is concerned. The long roots of the trees that, among other things opened for it channels to the air, are gone. The burrowing animals that used to loosen up the earth, man has driven away. More than that, the foot of the plough which has to press heavily on the subsoil in order to turn the furrow, smears and compacts the earth into a hard layer, which shuts out the air, and also--to a certain extent--the water from the lower levels.

[Illustration: HOW THE SOIL GETS ITS BREATH

Plants must have air to breathe, both above and below the soil, and the microscope is showing us here how a sandy loam allows the air to reach the roots.]

In mountain regions these "storm ploughs," as we may call them, not only help to renew and prepare the soil in the valleys, but are a part of the machinery of delivery of new soil from mountain to valley. When trees on the mountainside are overturned, they not only bring up the soil, which the mountain rains quickly carry to the valleys, but the roots having penetrated--as they always do--into the crevices of the rocks, bring up stones already partly decayed by the acids of the roots. These stones, as the roots die, decay and so release their hold, and also go tumbling down toward the valley.

Consider how much of this storm-ploughing must be done in the forests of the world in a single year, and that this has been going on ever since trees grew big on the face of the earth. In a storm in the woods of California, Muir heard trees falling at the rate of one every two or three minutes. And, as I said, it is precisely the trees that can do the most ploughing--the older and larger trees--that are most apt to go down before the wind. Younger trees will bend while older and stiffer trees hold on to the last. Before a mountain gale, pines, six feet in diameter, will bend like grass. But when the roots, long and strong as they are, can no longer resist the prying of the mighty lever--the trunk with its limbs and branches--swaying in the winds, down go the old giants with crashes that shake the hills. After a violent gale the ground is covered thick with fallen trunks[7] that lie crossed like storm-lodged wheat.

[7] Muir: "Mountains of California."

There are two trees, however, Muir says, that are never blown down so long as they continue in good health. These are the juniper and dwarf pine of the summit peaks.

"Their stout, crooked roots grip the storm-beaten ledges like eagle's claws, while their lithe, cord-like branches bend round completely, offering but slight holds for winds, however violent."

At The Storm Festival With Mr. Muir

Trees were among Muir's best friends, and he spent a large part of his life chumming with them. What do you think that man did once? He was always doing such things. He climbed a tree in a terrific gale so that he could see right into the heart of the storm and watch everything that was going on. Just hear him tell about it:

"After cautiously casting about I made choice of the tallest of a group of Douglas spruces that were growing close together like a tuft of grass, no one of which seemed likely to fall unless the rest fell with it. Being accustomed to climb trees in making botanical studies, I experienced no difficulty in reaching the top of this one, and never before did I enjoy so noble an exhilaration of motion."

And such odors! These winds had come all the way from the sea, over beds of flowers in the mountain meadows of the Sierras; then across the plains and up the foot-hills and into the piny woods "with all the varied incense gathered by the way."

[Illustration: THREE KINDS OF SEED THAT THE WIND SHAKES FREE

Here are three kinds of seed adapted for dispersal by the shaking action of the wind.]

Though comparatively young, these trees--the one Mr. Muir climbed into and its neighbors--were about 100 feet high, and "their lithe, brushy tops were rocking and swirling in wild ecstasy." In its greatest sweeps the top of Muir's tree described an arc of from twenty to thirty degrees, but he felt sure it wouldn't break, and so he proceeded to take in the great storm show.

"Now my eye roved over the piny hills and dales as over fields of waving grain, and felt the light running in ripples across the valleys from ridge to ridge, as the shining foliage was stirred by the waves of air. Oftentimes these waves of reflected light would break up suddenly into a kind of beaten foam and finally disappear on some hillside, like sea waves on a shelving shore."

This was his impression of the forest as a whole, a dark green sea of tossing waves. But if we study trees as long and lovingly as Muir did, we can pick out the different members of the family a mile away--even several miles away--by their gestures, their style of grave and graceful dancing in the wind.

[Illustration: TYPES OF FLYING MACHINE

Here is the type of flying machine that carries men. On the opposite page is the kind that carries the dandelion seeds.]

[Illustration: THE DANDELION-SEED FLYING MACHINE

The dandelion on the left shows how the seeds are kept in the "hangar" at night and on rainy days, shut up tight to prevent them from getting wet with rain or dew and so made unfit for flying.]

Muir especially mentions the sugar-pines as interpreting that storm to him. They seemed to be roused by the wildest bursts of the wind music to a "passionate exhilaration," as if saying "_Oh_, what a glorious day this is!"

This was the picture part of it--the glorious moving-picture show. Now listen to some of the music:

"The sounds of the storm corresponded gloriously with the wild exuberance of light and motion. The profound bass of the naked branches and boles booming like waterfalls, the quick, tense vibrations of the pine-needles, now rising to a shrill, whistling hiss, now falling to a silky murmur. The rustling of laurel groves in the dells, and the keen metallic click of leaf on leaf--all this was heard in easy analysis when the attention was calmly bent.

"Even when the grand anthem had swelled to its highest pitch I could distinctly hear the varying tones of individual trees--spruce, fir, pine, and oak--and even the infinitely gentle rustle of the withered grasses at my feet."

When the winds began to fall and the sky to clear, Muir climbed down and made his way back home.

"The storm tones died away, and turning toward the east I beheld the countless hosts of the forests hushed and tranquil, towering above one another on the slopes of the hills like a devout audience. The setting sun filled them with amber light, and seemed to say while they listened:

"'My peace I give unto you.'"

Hide And Seek In The Library

Did you know that the ash and maple seeds actually have screw propellers, like a ship, so that they can ride on the wind? Pettigrew's great work, "Design in Nature," makes this very plain, both in word and picture.

In what way does the wind help to _produce_ the seed of grasses as well as carry and plant them? (Any encyclopaedia or botany will tell you how plants are fertilized.)

How could a tempest that blew down a tree help its seeds to get a start? Wallace, in his "World of Life," says that on a full-grown oak or beech there may be 100,000 seeds that are thus given a better chance of life.

Speaking of "wind ploughs," what is the object of ploughing anyway? The article on preparing the seed bed in "The Country Life Reader" tells about what ploughing means to the soil and also:

Why good soil takes up more room than poor.

Why it is a good thing to plough deep, but a bad thing, if you don't do it just right.

And farther on there is a most inspiring poem about the history of the plough from the days of early Egypt to the present. It begins like this:

"From Egypt behind my oxen, With their stately step and slow, Northward and east and west I went, To the desert and the snow; Down through the centuries, one by one, Turning the clod to the shower, Till there's never a land beneath the sun But has blossomed behind my power."

The deserts have helped to make western China fertile. How did they do it? (Look at your geography map and remember that the prevailing winds of the world are westerly.)

You'll find many interesting things about the winds and the soil in Keffer's "Nature Studies on the Farm" and Shaler's "Outlines of Earth's History." Shaler's "Man and the Earth" says a single gale may blow away more soil from an unprotected field than could be made in a geological age, and an hour's rain may carry off more than would pass away in a thousand years if the land were in its natural state. He also tells what to do to prevent the best part of ploughed fields from being carried off by the wind.

Have you any idea how far seed may be carried by a hurricane? Wallace, in his "Darwinism" deals with this question, and it's very important in the story of the earth. Beal's admirably written and illustrated little book on "Seed Dispersal" tells a world of interesting things about the wind as a sower. For instance:

How pigweed seeds are built so that wind can help them toboggan on snow or float on water;

How wind and water work together in the distribution of seeds;

About seeds that ride in an ice-boat;

About the monoplane of the basswood;

About the "flail" of the buttonwood, and how the wind helps it to whip out the seeds; and how the seeds then open their parachutes.

Dandelions go through quite a remarkable process in preparing for flight. I wonder if you have ever noticed it. Before the seeds get ripe Mother Dandelion blankets them at night and puts a rain-cloak on them on rainy days, and just won't let them get out, as shown on page 51. And do you know how she opens the flowers for the bees on sunshiny days?

There is no island, no matter how remote, that isn't supplied with insects. How do you suppose they get there? You may be sure the wind has something to do with it or I wouldn't mention the subject at the end of this chapter. (Wallace: "Darwinism.")

[Illustration: THE WEST WINDS AND THE RAINS

On the western slopes of this mountain the trees, with the help of the winds and the rain, climb to the very summit, while the other side of the mountain remains only a barren rock. The moisture-laden winds from the west glide up the slope, the air expands as it rises, the expansion cools it and down comes the rain! But the eastern slope gets little or none of it.]

Chapter IV

(April)

The higher Nilus swells The more it promises; as it ebbs, the seedsman Upon the slime and ooze scatters his grain, And shortly comes the harvest.

--_Shakespere: "Antony and Cleopatra."_

The Bottom-Lands

All that wind was bound to blow up rain. I said so at the time. And, sure enough, here it is; right where we want it, at the beginning of April, a month famous for its rains.

The work of the rains is going to make one of the most interesting chapters in the long story of the dust. At least I hope so. But don't think I intend to tell it all. Why, it would make a whole book in itself. But you can believe every single thing I do tell, no matter how it makes you open your eyes; for, if I've helped it rain once I've helped it rain a million times!

I. The March Dust And The April Rains

How Rain Goes Up Before It Comes Down

It's this way: You remember how you can "see your breath," as we say, on a cold morning? Well, that's because the moisture in your breath is condensed by the cold. Now as the waters of the earth--the seas, lakes, rivers, ponds, and so on--are warmed by the sun, the air above them is filled with moisture, for the heating of the air causes it to expand and draw in moisture from the water like a sponge. Expansion makes it lighter also, and it rises. Rising, it turns cooler, and the moisture condenses and comes down as rain. Mountains usually have clouds around them because moist air striking the mountainside is driven up the slope, cooling as it rises. So rain and snow fall often in mountain regions, and that's why so many rivers rise in mountains. The moist air is also condensed when it meets other and cooler air currents. But right here is where the work of the dust comes in. For to make rain you've got to have clouds, and clouds are due to this moisture collecting around the little particles of dust of which the air is full. When these little motes of matter become cooler than the air that touches them the moisture in the air condenses into a film of water around them. Fairy worlds with fairy oceans floating in the sky!

Each of these baby worlds is falling toward the big world below. But very slowly; only a few feet a day, so that even if nothing happened it might be months--yes, years--before it would come to the ground, even in still air. But when air is very thick with moisture the water films on these dust particles grow rapidly, and thus increasing in weight, they fall faster and faster, and finally strike the earth as raindrops.

But here's another thing that helps. On the way down two or more raindrops, falling in with each other, will go into partnership--melt into one--and then they hurry down so much the faster. That's why the sky grows darker and darker just before a rain, and why the lower part of a rain-cloud is the darkest: the little raindrops are forming into bigger raindrops as they fall.

The Little Artists That Shape The Clouds

But the shapes of clouds are supposed to be due to another thing, the mysterious force we call electricity, and that other mysterious force we call gravity. Just as the worlds attract each other by gravity so these raindrops--or dust grains growing into raindrops--are drawn toward one another. Here's where Electricity steps in. These rain particles are full of electricity and when two of these electrified particles meet in the air--unless they strike one another in falling, in which case, as I said a moment ago, they blend into one--they get very close together and yet keep dancing around one another without touching! It is this dancing about that makes all those strange and beautiful and ever-changing forms in the vast picture-gallery of the sky.

Of course the wind currents help to change these shapes, but I'm talking about the original designs.

II. The Raindrops And The River Mills

So much for the dust that helps make raindrops; now for the raindrops that help make dust. This the raindrops do in several ways. Falling on big rocks or decaying pebbles, for example, they pound loose with their patter, patter, patter, any little bits of soil and grains of sand that have been made by the other soil makers--the sun, the wind, the lichens, the chemists of the air, and so on. This soil and these sand particles, if there is already any depth of earth there, they carry down into the ground. Some of this soil, with various stops and mixings with other soils on the way, finally reaches the sea, where it helps to make the rich limestone soils for the Kentuckies of millenniums yet to be, by supplying food for sea creatures and lime for their shells. For these shells become limestone when the shell-fish are through with them. Mother Nature, in addition to feeding her big, hungry families of to-day in the plant and animal world, is always laying by something for the future. But before it gets back to the sea, by far the greatest part of the ground-up soil the rivers carry is spread out in the lowlands in those "alluvial plains" your geography tells about and that make a large proportion of the fertile farms of the world. If the raindrops fall on comparatively barren rock--in the mountains, say--they carry some of this fresh soil to the mountain valleys below, and some of it they may spread in bottom-lands a thousand miles away, where the new soil helps feed the plants. The sand grains in it not only help the soil to get its breath by making little air spaces, but these sand grains themselves slowly decay and so make more soil.

[Illustration: WHAT IRRIGATION DOES FOR DESERTS

It is such land as this, in the arid regions of the West, that irrigation converts from a desert to a garden of abundance. The soil is rich in all the substances that plant life needs.]

But it isn't alone that they carry away the soil already made and bury the sand grains. Some of the raindrops soak into cracks in stones and dissolve the material that binds the rock particles together, and so get them ready to give way under the fairy hammers of the next shower that comes along.

After Nature finally gets an original waste of barren rock all nicely set with grass and flowers and trees and things, the raindrops help to make soil in still another way. Soaking through the decaying leaves, they pick up acids which are just the thing for eating into rock and crumbling it into soil. To be sure, the water soaking into the soil and coming out of springs carries some plant food away with it; but it takes it to lands farther down the river valleys, and more than makes up for what it carries away by the new soil made by its acids from the rocks, as it soaks into their pores and runs among the cracks.

How Raindrops Manage To Grind Up The Rocks

Moreover, raindrops actually grind up rocks. In order to do this a lot of raindrops have to get together, to be sure, and become rivers; but after all it's the raindrops that do it. There'd never be any rivers if it weren't for the rains and, of course, the snows.

Well, anyhow, the rivers, besides running other people's mills, have mills of their own; and millstones. Most of these stones originally came from mountains and were brought into the milling business by mountain streams, with the help of Jack Frost. For the frost not only pries stones from the mountains and so sends them tumbling down the slopes, but it keeps edging them along and edging them along, farther down, after they have fallen. You'd hardly think that, would you? Yet it's simple enough. The water in the pores of the rock expands when it freezes and that makes the whole rock expand, for the time being. Then when the frozen water in the rock pores thaws out, the rock contracts, and this spreading out and pulling together, small as it is, causes the rock to keep hitching along down the incline; oh, say a fraction of an inch a year. But still, in the course of the ages, these inches foot up, and after a while this tortoise-like gait lands the stone--lands tens of thousands of such stones--in the beds of the mountain torrents that run along at the bottom of these inclines. There they get ground together and so grind out more soil material, particularly when the floods are on, with the melting of the snows in spring and the falling of the heavy and frequent rains.

[Illustration: AN OLD RIVER MILL

It used to do a lot of business--this old river mill. Its grist was ground-up rock that helped make fine farming land in the bottoms along the river's course. Such mills, called "pot holes," are found in the rocky floors of rapid streams, where the eddying current or the water of a waterfall wears depressions in the bed. Into these depressions stones are washed, and then by the whirl of the flowing water kept going round and round, grinding themselves away and grinding out the sides and bottom of the mill.]

Another curious thing is how the river mills help themselves to new millstones when they need them. If a river hasn't enough for its work, it has a way of drawing on its banks for more. Whenever the stones in its bed get scarce, so that it can make comparatively little new soil--having so few stones to grind together--it proceeds to dig its own bed deeper, since this bed is no longer protected by a rock pavement in the bottom. This, of course, deepens its channel, and so adds to the steepness of the slope of its banks. Then, owing to this increase in the incline of the slope, more rocks tumble in, and the "milling business" picks up again.

The Governor In The River MILL

But there may be too much of a good thing; the rocks may come in faster than the river mill can take care of them. Then the river bottom becomes so completely paved over that the channel stops wearing down at all, to speak of, and the river remains at the same level until the rains and the wind and other workers have worn the banks down and lessened the incline. Then, with fewer and fewer fresh stones tumbling in, the river gets a chance to catch up with its work.

It is this ground-up rock stuff of the mountain river mills, made by the grinding of the running streams all the way down, that has helped form the rich bottom-lands of the Mississippi Valley. For uncounted ages, the water of the Mississippi and its tributaries have been at work, and by the time you get down into southern Louisiana you come to the delta where this rich soil has been piled up for more than 1,000 feet above the bottom of the old Mediterranean Sea, that used to reach north and south across the country.

You remember the lines, don't you:

"Little drops of water, little grains of sand Make the mighty ocean and the pleasant land."

Well, this is how they do it; all this that I've been telling you.

[Illustration: _Courtesy of the Scientific American._

Thousands Of Farms Poured Into The Gulf

The Father of Waters is a good farmer in some respects but needs training in others. The Mississippi's floods, like those of Father Nile, enrich the bottom lands, but the river is apt to break all bounds and do a lot of damage. Moreover, every year it carries away thousands of acres of good soil and pours it into the Gulf. How to teach the Mississippi to work in harness, as the Nile has been taught to do in recent years, is one of the problems which will require all of Uncle Sam's ingenuity and skill to solve. A good deal of the yearly waste could be prevented, however, by the various means employed by good farmers.]

III. How The Rivers Act As Bankers For The Farmers And The Sea

We speak of river banks and the kind of banks that handle those promissory notes our arithmetics tell about as if they were entirely different; and so they are, I suppose, if one just looks at the surface of the thing. But if we dig into the subject a little we shall see that they are much alike in the fact that one of the principal businesses of both kinds of banks is to make loans at interest. Men's banks loan money, to be sure, while the river banks loan pebbles, but if it were not for these pebble loans there would be a mighty sight less money for the banks to loan, or the farmer to borrow; and the way both banks do business ought to be a good lesson to certain farmers I know, who seem to think they can always be cashing checks on their banks--the farm lands--by hauling away the crops without ever putting anything back.

[Illustration: WHERE THE RIVERS ACT AS BANKERS

Here is a fine piece of bottom land, one of those "banks" where the rivers keep "checking accounts" for the farmers and the sea; using pebbles for currency, as explained in this chapter.]

How The Rivers Place Pebbles On Deposit

The rivers make loans to the soil by depositing pebbles in the broad bottom-lands along their banks, and then draw interest by carrying along to other lands, from time to time, some of the fine rich soil these pebbles help make by their decay. And the river does this in regular banking style, "checking out" the pebbles from time to time, and then depositing other pebbles in their places. Take the banks and bottom-lands of the Mississippi River, for example. It has been estimated that it requires about 40,000 years for a pebble to make the journey to the Gulf from the mountains of a tributary stream where it was first broken from the rock as a sharp fragment.

The first part of the journey in the mountains is over steep down grades, and so is comparatively fast, but as the river gets farther from the mountains, the slope of its bed becomes less and less, the onward movement is slower and slower, and more of the pebbles stop to rest. In times of flood they are carried far away from the regular channel and spread over the wide flood-plain of the river. Then, as the flood goes down, they are left buried there under a coating of mud. So buried, they decay and enrich the soil. Then the next flood that comes along sweeps the pebbles with it--checks them out of the bank--but at the same time carries away not only some of the soil richness which these pebbles helped to make but the soil material made by the decay of the vegetation these pebbles thus helped to grow, such as the roots and blades of wheat and corn and stubble and chaff left in the fields. That's the interest on the loan. Then, when the flood subsides, the pebbles are again deposited farther along in the river's course, but meanwhile the same flood has brought fresh deposits of pebbles from up-stream, and these are left in place of those taken away.

River Banking And Human Civilization

This banking business has been going on for ages and is a very important part of the history of civilization. Here and there along the sides of the older and larger river valleys are found the remains of ancient plains. These plains are now, many of them, quite a distance above the level of the stream. This means that they were at one time the bottom-lands of that same stream, but the stream, as it dug deeper and deeper into its bed, grew narrower, and so abandoned its old flood-plains. As savage man gradually settled down and took to farming, he found these bottom-lands, with their rich, mellow soil, just the thing for his crooked-sticks and stone hoes--the only kinds of ploughs and hoes there were in those days. With such crude farming tools he couldn't have managed to scratch a living on any other kind of soil. When the river floods came along, all these crooked-stick farmers had to do was to keep out of the way until the floods went down, and there were their fields all fertilized for them, as good as new, and they could go on for thousands of years working the same fields without ever bothering their heads as to whether they needed any lime or potash or nitrogen, or anything; for they didn't. The river floods attended to all that.

[Illustration: FATHER NILE AND THE MAKING OF EGYPT

"Egypt," said Herodotus, "is the gift of the Nile"; and it is true so far as her fertile lands are concerned. The ancients attributed the annual floods to the god of the Nile, as shown in that statue of Father Nile in the Vatican. Below is a threshing scene in Egypt painted by Gerome. The last picture, from a carving in the tomb of an Egyptian noble, shows how they ploughed and sowed in the Pyramid age.]

So, in course of time, civilizations such as those of Egypt and India and Persia grew up, and in further course of time these civilizations spread into Europe, and finally to the New World.

How River Banks Go Bankrupt

Now all this is very well, this leaving it to Nature to fertilize the fields, where everything is just right for it, as it is along the Nile, but in most lands it won't do it all. The trouble is that, in raising the grain foods, the ground must be kept free of grass and weeds, and well ploughed during the rainy season. But the same rains that water the fields wash more or less good soil into the streams; much more than Nature alone can put back. For instance, down in Italy where, if the old forests were still there, the rains wouldn't wash away more than a foot of soil in 5,000 years, this soil is being carried into the Po, and by the Po emptied into the sea so fast--a foot in less than 1,000 years--that if you visit Italy to-day, say, and then go back in ten years, you'll see bare rocks on many a hillside that is now clothed in green. On such rocks the soil is already thin, and in ten years more it is all gone; all washed away! This thing is going on all around the shores of the Mediterranean. You are constantly coming on sections of country that used to be covered with great forests and prosperous farming communities where the soil has vanished, and many stretches of barren, rocky land where hardly a weed can find a foothold.

[Illustration: WHAT HAPPENS TO THE LAND WHEN THE TREES ARE GONE

Could anything be more desolate? You can see from this example how vital to our national life is the forest conservation work of our government. Trees, by the network of their roots, keep the soil from washing away, retain moisture by their shade, and absorb the water of the rains and the melting snows so that it reaches the rivers and the creeks gradually. But when the trees are gone the water, unchecked, rushes down the slopes in floods, washing away the precious soil and leaving them as barren as a desert.]

"But, what are you going to do about it?" you say. "You can't change the slope of the hills, can you? And the farmer has _got_ to plough his land--you just said so yourself."

Yes, he's got to plough his land, to be sure; but so has he got to have pasture for his live stock. If he hasn't any live stock, that just shows what kind of a farmer he is. Every farmer ought to have live stock. Corn always brings a great deal more when it goes to market "on four feet," as the saying is; and, besides, the live stock give back to the fields, in the shape of manure, a large part of what they eat. Now, if you have live stock you must have pasture, and all land with a slope of more than one foot in thirty should be used partly for pasture and partly to grow wood for the kitchen stove, and hickory-nuts and walnuts for winter firesides. Although the land slopes, the mat made by the grass roots will keep it from washing away.

"But suppose you lived where there wasn't any land to speak of that didn't tip up; in New England, say--what would you do then?"

Leave the upper part of the slopes in the woods. Then the water that carries off the soil will not run entirely away, as it does in ploughed fields, but will creep down slowly, and, charged with the decay of the woods, help fertilize the lower lands and change the rocks beneath them into soil--the acids from the decaying vegetable matter eating into them.

"But still," you say, "there are farm lands that must be ploughed even if they do wash away; they're all the land a man has, sometimes. What then?"

Plough deep. Then the soil soaks up more of the rain and lets the water pass away in clear springs. This not only saves soil but, as we have just said, helps to decompose the subsoil and the bed rock.

Then there's another thing that good farmers do in such cases. They plough ditches along the hillside leading by a gentle slope to the natural watercourses; so the water of the rains, instead of going down the hills with a rush, and going faster the farther it runs--like a boy on a toboggan--is caught and checked in these sloping ditches, and much of the soil it contains deposited before it reaches the streams.

[Illustration: HOW THE FRENCH PROTECT THEIR HILLSIDE FARMS

This is how the French peasant keeps the mountain torrents from carrying off his precious soil.]

The best way of all, of course, is to build terraces, as they do in the thickly settled parts of Europe. But this is only profitable for the more valuable crops and not for ordinary grains.

Such Spendthrifts Of God'S Good Soil!

My, but it's a shame the way we've wasted soil in this country. What spendthrifts! To start with--when the country was first settled--there seemed no end to the fine land, and every one could have a good farm for the asking. All he had to do was to make his wants known to Uncle Sam and then go out and help himself. What happened then? Why, what always happens? Easy come, easy go. These pioneer farmers worked their farms for all there was in them; didn't bother, many of them, even to haul the barn manure into the fields. Then when the old farm was exhausted they moved off to new lands and did the same thing over again.

[Illustration: A HOME IN THE DESERT

Doesn't look much like a home in the desert, does it? But it is--a lovely home in what the old geographies called "The Great American Desert." In the Sahara oases are few and far between, but modern irrigation engineering makes oases to order--thousands and thousands of acres of them!]

They ploughed on steep hillsides; they allowed gulches to form, as they will quickly do on sloping ploughed land, if you don't watch out; they cut away the timber. It's easy in a hill country like the eastern part of the United States to have all the good top-soil washed away in twenty years after the forests have been destroyed; the good soil that it probably took 2,000 years to make.

Doctor Shaler[8] estimated that in the States south of the Ohio and the James Rivers more than 8,000 square miles of originally fertile land had, by this shiftless and thoughtless way of doing things, been put into such a state that it wouldn't grow anything; and over 1,500 square miles of this, actually worn down to the subsoil, and even to the bed rock, so that it may never be profitable to farm again--at least not in our time--no matter what they do!

[8] "Outlines of Earth's History."

I knew a farmer with a small son to whom he intended to leave the farm when he grew up, who did things like that for twenty years. By the time the little boy was old enough to vote, there was no farm to leave; all the good part of it was gone.

Serious thing for that little boy, wasn't it?

Hide And Seek In The Library

What have burrowing animals to do with the drainage system of the land? (Keffer's "Nature Studies on the Farm.")

How do angleworms help drain the soil?

How do the forests help make good use of the rain that falls, not only for themselves but for the rest of us?

How do the rains help to warm the ground in the spring? The heat they carry into the soil is produced in two ways. The book mentioned above tells of one of these ways, and Russell's little book, "The Story of the Soil," tells of another.

Beale's "Seed Dispersal" tells how the raindrops (working together, of course) help plant maple, elm, sycamore, willow, and other trees that grow by the waterside, to scatter their seeds.

You'd be surprised what a series of adventures the seeds of a bladderwort have before they get planted on some new shore, after having left the parent shrub. First, they float down-stream, as you know, but when autumn comes on, what do you suppose they do? They go to bed. Where? Right in the bottom of the stream. Then how do they ever get up and get planted on the shore? Well, you just look it up in that Beale book and see.

Do you know how the rains help to get the mineral food up into the plant?

And why swamps are such poor producers?

And how the sun acts as a pump for the plant world?

You will find answers to all these questions in Shaler's "Outlines of Earth's History" and in your books on botany and agriculture.

Russell's book on the soil tells how the ancient Gauls and Britons used to fertilize their land with marl, and how the tides help to fertilize England. It's just the reverse of the way Father Nile looks after Egypt, as you will see.

If you want to read an interesting description of the difficulties of farming on wet lands, you will find it in this meaty little book.

If you don't know how serious a thing it is to let gullies form in land, look it up in Shaler's "Man and the Earth" and you will see.

How do you suppose deserts that get so little rain themselves could _help make it rain_ in other places? For example, the desert of Thibet is the chief cause of the monsoon rains that do so much for India. That part of your geography that explains the circulation of the air will help you figure this out; particularly with a map under your eye that shows the relative location of the desert and the Indian Ocean, over which the monsoon winds blow.

[Illustration: AN EXAMPLE OF MAN'S DEBT TO THE EARTHWORM

Much of the earth's Maytime bloom and beauty is due to the labor of our humble little brother of the dust, the earthworm; a striking fact which was never recognized until the great Charles Darwin looked into the matter and wrote a book about him. This picture by Millet is called "Springtime" and hangs in the Louvre, in Paris.]

Chapter V

(May)

It may be doubted whether there are many other animals which have played so important a part in the history of the world as these lowly organized creatures.

--_Darwin: "The Formation of Vegetable Mould."_

What The Earth Owes To The Earthworm

Suppose father had a hired hand who would plough his fields, fertilize them at his own expense, build his own house, board himself, and for all this ask only the privilege of living on the place, studying Botany, Geology, and Geometry, and enjoying the scenery.

"Where can I get a man like that?" I imagine father saying.

"You've got him now," you might reply. "He's already working for you--thousands of him, and has been working for you--millions of him--for thousands and millions of years."

We have all known him well from boyhood by several names--angleworm, fishworm, earthworm. He also, as you will find in the dictionary, has a nice long Latin title. And it is particularly fitting that his name should be so associated with antiquity, since he belongs to one of the oldest families in the world; a family far older than the Roman Empire itself, which his people long ago helped grind back into the dust from which it came.

And, speaking of Romans, every few years Mr. Earthworm does what Julius Caesar did, captures the whole of England--all the best parts of it--and then, unlike Caesar, gives it back to the English, made over again, better than it was before, as you will see.

I. The Cities Of Worms

If you happen to be a high school boy you, of course, know about a certain city of Worms and what great things took place there once upon a time, but there are many cities of worms on any good farm, and each has more inhabitants than the famous city of Worms of history--something like 25,000 to the acre; and, in garden soil, 50,000!

[Illustration: ANOTHER "CATHEDRAL OF WORMS"

In the story of the Reformation in your history you will read of a certain Cathedral of Worms and what took place there once upon a time. Here is a "cathedral of worms" as interesting to the student of nature as that famous edifice is to the historian and the architect. It is the tower-like casting of a big earthworm and was found in the Botanic Garden at Calcutta. The picture is "life-size."]

Did you ever notice how big boulders in a field are frequently sunk into the ground as if dropped from a great height? It is the earthworms that help sink them in the course of their soil-making. They like the moist shelter of the stones and burrow under them. Finally the weight of the stones crushes the burrows, and so the stones sink down.

Pioneer Life Among The Earthworms

Poor soil, as every boy knows, is a poor place to look for fishworms. But you have noticed that the mounds the worm throws up on such soil are larger than those on rich soil. The reason is that the soil, being less nutritious, the worm must eat more of it and, in so doing, pulverizes and fertilizes it. But a menu of earth alone not being to the earthworm's liking, undesirable regions have fewer of these farmers working underground; and this, for the same reason that these regions are sparsely settled on the surface--it is so hard to make a living.

So the earthworms may be said to have a decided taste in landscape. They don't care for desert scenery like Gerome's picture of the lion's big front yard,[9] but they are very fond of orchards where the soil is rich and leaves are plenty. The pathways artists are fond of putting in landscapes would also probably attract the eyes of earthworms--if they had any, for the worms prefer soil a little packed, as it is in pathways, because it makes more substantial burrows. And, singularly enough, the worms also like most the very thing that the artist emphasizes to lead the eye into his picture--the border lines that _define_ the path. It is along the edges of a pathway that you find most worms.

[9] "The Two Majesties." This painting, by a great French realist, shows a lion getting home rather late, after his night out, stopping for a look at the rising sun; a thing with which, owing to his habits, he is not very familiar.

[Illustration: _Painted by F. O. Sylvester._

_Painted by Westman._

The Earthworm'S Taste In Scenery

Two features common to both these pictures--the trees and the pathways--appeal to earthworms as well as artists, for reasons you have learned in this chapter.]

The earthworm, in addition to working over and fertilizing the soil already made, actually helps make soil out of rock. He does this in two ways: (1) With acids--for, like the Little Old Man of the Rock, he is a chemist; (2) by grinding up rock in a little mill he always carries with him.

How The Earthworm Cooks His Meals

The earthworm's favorite diet is leaves and he has a way of cooking them. It is not quite like our way of cooking beet or dandelion leaves, but it answers the same purpose--it partially digests them. In glands, in his "mouth," he secretes a fluid which, like our saliva, contains an alkali. But the earthworm's alkaline solution is much stronger, and when he covers a fresh green leaf with it--as he is usually obliged to do in Summer when there are so few stale vegetables, the kind he prefers, in his market--the leaf quickly turns brown and becomes as soft as a boiled cabbage.

Of course, there are always dead leaves in the woods, and these, which even the cow with her fine digestive outfit cannot handle, are a delight to the earthworm; for he also has a much larger supply of pancreatic juice than the higher animals, and this takes care of the leaves after he has swallowed them. He swallows bit by bit; just like a nice little boy who has been taught not to bolt his food.

The acids in the earthworm's "stomach," acting on the leaves, help make other acids which remain in the soil after it has passed through the earthworm's body and help dissolve those fine grains of sand which make your bare feet so gritty when mud dries on them. And, not only that, but this coating of soil lying upon the bed rock hastens its decay; for the earthworm's burrow runs down four to six feet, sometimes farther.

Besides the soil he thus grinds up and fertilizes so well with leaf-mould--what your text-book on agriculture calls "humus"--the earthworm does a lot of useful grinding in connection with the building of his house. He begins, as we do, by digging the cellar; but there he stops, for _his_ house is _all_ cellar! He makes it in two ways: (1) By pushing aside the earth as he advances; (2) by swallowing earth and passing it through his body, thus making the little mounds you see on the surface.

The Earthworm System At Panama

A principle similar to his swallowing operations is frequently employed in engineering; as in making the Panama Canal, where dredging machinery dug out swamps and pumped the mud through a tube into other swamps to fill them up and help get rid of the mosquitoes.

In pushing the earth away the worm uses the principle of the wedge, stretching out his "nose"--as you have often seen him do when crawling--and poking it into the crevices in the ground; much as the wheat roots poke _their_ little noses through the fertile soil the earthworm makes.

And, as in human engineering and the work of the ant, the earthworm doesn't throw the dirt around carelessly. He casts it out, first on one side and then on the other; using his tail to spread it about neatly.

The Tiling In The Earthworm'S House

The walls of the earthworm's house are plastered, too. At first they are made a little larger than his body. Then he coats them with earth, ground very fine, like the clay for making our cups and saucers, and for making the beautiful white tiling on the walls at the stations of a city subway. When this earthworm "porcelain" dries it forms a lining, hard and smooth, which keeps the earthworm's tender body from being scratched as he moves up and down his long hallway. It also enables him to travel faster because it is smooth, and it strengthens the walls.

The burrows which run far down into the ground, as all finally do toward Autumn, end in a little chamber. Into this tiny bedroom the worm retires during the hot, dry days of August and there he spends the Winter--usually with several companions, all sound asleep, packed together for warmth.

And Rugs On The Floors!

Sometimes the Summer and Winter residences are quite ambitious, several burrows opening into one large chamber and each tunnel having two, sometimes three, chambers of its own--like a fashionable apartment with its main reception-room, and still more like the central sitting-rooms in Greek and Roman palaces. And the earthworm seems even to have some idea of mosaics, for it is the general practice to pave these chambers with little pebbles about the size of a mustard-seed. This is to help keep the worm's body from the cold ground. In addition to the mosaic floors the earthworms have rugs with lovely leaf patterns like the Oriental rugs that are so highly prized; and, as in the case of genuine Oriental rugs, no two patterns are alike. These rugs are leaves which the earthworm drags into his burrow, not for food but for house furnishing. When used for house furnishing they are placed in the entrance-hall; that is to say, they are used to coat the mouth of the burrow to prevent the worm's body from coming in contact with the ground. The mouth of the burrow, of course, is just where it is coldest at night in the Summer, the time of year when the earthworm spends a great deal of his time in the front of his house. The surface of the earth, you know, cools very rapidly after sunset and the dew on the grass in the morning is so cold it makes your bare feet ache. The worm requires damp earth around him because he breathes through his skin and must keep it moist, but at the same time he is sensitive to cold.

And to drafts. Ugh!

Pebble-Fort Defenses Against The Foe

So he is very careful to keep the front door closed. This he does by stopping it up with leaves, leaf stems, and sticks. He also protects the door with little heaps of smooth round pebbles; but these pebbles are of a larger size than those he uses for paving the floor of his chamber. Besides helping to keep out drafts these pebbles serve another purpose. As our ancestors, the cave-builders, barred the door with boulders to keep out bears and other unwelcome callers, so the earthworms are protected by the pebbles, to a certain extent, from one of their enemies--the thousand-legged worm. Because of these little forts, the earthworms can remain with more safety near the doorway and enjoy the warmth of the morning sun. (So we might have reproduced Corot's "Morning" as a kind of landscape the earthworm enjoys!)

II. The Mind Of The Earthworm

From all of which you can see the earthworm, for what small schooling he gets, is a very bright boy! If we were as bright, according to our opportunities, we would probably have answered long ago such puzzles as the question whether there is really anybody at home in Mars, how to keep stored eggs from tasting of the shell, and other great scientific problems of our day.

Where Mr. Earthworm Keeps His Brain

Just as we have little brains in the tips of our fingers, the earthworms have brains in the ends of their "noses." They have neither eyes nor ears, but, like that wonderful girl, Helen Keller, they make up for the lack of these senses, to a remarkable degree, by the development of the sense of touch. They acquire quite a little knowledge of Botany, for example. They not only know that leaves are good to eat, but they know which is the "petiole" and which is the "base." They always drag leaves into their burrows by the smallest ends, because this makes it easier to get them through the door. And it is not by mere instinct that they do this. Supply worms with leaves of different form from those which grow in the region where they live, and they will experiment with them until they find just the best way in which to pull them into the burrows. After that they will always take hold of them so, without further experiment. That is the majority of them will do this; for earthworms are like other little people--all of them are not equally ambitious or studious.

And the earthworm also knows something about Geometry. Cut paper into little triangles of various shapes and pretend to the worms that they are leaves by scattering them near the mouths of the burrows. Then remove the leaves with which the burrows are stopped. The worms will pull in the slips to close the door and they will--most of them--take hold by the apex of the triangle because that is the narrowest point.

The Earthworm'S Taste In Music

So you see the earthworm is a very cultivated country gentleman with his knowledge of Botany and Geometry, and his taste for landscape. But this is not all. He also has opinions about music. There are certain notes that apparently get on his nerves. Put worms in good soil in a flower-pot, and some evening when they are lying outside their burrows set the pot on the piano and strike the note C in the bass clef. Instantly they will pull themselves into their burrows. They will do the same thing at the sound of G above the line in the treble clef. Although they cannot hear, they are sensitive to vibrations, and these are carried from the sounding-board of the piano into the pot. They are less sensitive when the pot itself is tapped. The music seems to go right through them.

Why The Early Bird Gets The Worm

Except in rainy weather worms ordinarily come out of their burrows only at night. By early morning they have withdrawn into their holes and lie with their noses close to the surface to get the warmth of the morning sun. Then the early bird gets _them_! The reason a robin cocks his head in such a funny way--like a lord with a monocle--just before he captures a worm, is not because he is _listening_, as many people think; for the worm isn't saying a word and he isn't moving, and wouldn't make a bit of noise if he did move. The robin's eyes are on each side of his head and not in the middle of his face like ours, so he must turn his head in order to bring his eye in line with the hole where he sees the tip of Mr. Earthworm's nose.

[Illustration: THREE EARLY BIRDS. FIND THE THIRD

Don't they look happy--these two tow-heads? They are evidently going fishing in the early morning. Another early bird--several of him--that we are saying a good deal about in these pages is to be found in the can. Still another, the one at the bottom of the page, is taking advantage of the earthworm's family habit of warming his "nose" in the early sun rays.]

[Illustration]

And many people also believe that earthworms come down with the rain. Even park policemen believe it. At least, one said to me, in Central Park:

"In dhry spells ye won't see wan. But let there come a little shower an' th' walks and the dhrives will be covered wid them; like the fairy stones that fall wid the rain in the ould counthry."

Do Earthworms Come Down With The Rain?

The reason you see so many worms after a rain is that earthworms like moisture, and the rain seems to make them feel particularly good and breed a spirit of adventure. So out of their holes and away they go! A rain is their shower-bath; and you know how a shower-bath makes you feel. The mornings when the earthworms are apt to be thickest are those following a comparatively light rain in early Spring when the worms have recently awakened from their long Winter nap. With the beginning of the rainy season in the Fall, the worms also do a good deal of travelling into foreign lands, but in both Spring and Fall you will usually find more worms after a light shower than after a long, heavy downpour. If the worms were drowned out it would be the other way around, don't you see?

To be sure, you will often find dead worms in shallow pools by the roadside; particularly after Autumn rains. These are sick worms and the chill was too much for them. But it's remarkable how low a temperature a good husky angleworm can stand. A professor in the University of Chicago, near which I live, tells me he has often found the ground in the neighboring park covered with worms after November rains when his hands, and those of the students who were helping him gather them for study, were numb with the cold.

And how much work do you suppose these farmers do in grinding up and fertilizing the soil? In many parts of England the whole of the best land--the vegetable mould--passes through their bodies every few years, and they are doing similar work all over the world.

They not only fertilize the earth by mixing it with the leaves they eat and those that decay in their burrows, but their castings help to bury fallen leaves and twigs and dead insects, and they also bring up lower soil to the surface, thus increasing its fertility. And by loosening the soil they let in more air. Remember that roots, like people, must have air.

III. The MILL Of The Earthworm

For the grinding up of the earth and the leaves, the earthworm has, as I have already said, a little mill that he always carries with him. Do you know what a gold mill is? Well, a gold mill is a mill that grinds up rock and so grinds out the gold. The earthworm's mill, in a manner of speaking, also grinds out gold, for it grinds the little particles of stone in the soil, and this soil grows fields of golden grain.

The earthworm's mill is his gizzard. This gizzard is made and works very much like the gizzard of the chicken. And like the chicken the earthworm swallows little stones to help his digestion. So these stones, too, are ground into soil.

Like the chicken's gizzard the gizzard of the earthworm is lined with a thick, tough membrane, and it has muscles--such muscles! There are two sets of these muscles and they cross each other somewhat like the warp and woof of the cloth in your clothes. The muscles that run lengthwise are not so very strong, for all they have to do is to help the earthworm swallow, but the muscles that run around the gizzard are wonderfully strong. They are about ten times as thick as the other muscles. One of Mr. Earthworm's French biographers[10] calls these muscles "veritable armatures"; that is, freely translated, "veritable hoops of steel."

[10] When you study French, if you want to read this book--like most French works on science it is very interesting--ask for Perrier's "Organization des Lumbricus Terrestris."

I said, in the second paragraph above this, that worms swallow grains of sand and stones to help their digestions, as chickens do. But the earthworm saves time, for he takes the stones with his meals; just as some Englishmen, fat old squires, when they get along in years, or for any other reason are a little weak in their digestive regions--keep pepsin on the table with the pepper and salt.

And--believe it or not--the earthworm actually makes his _own_ millstones sometimes! The chalk in the chalky fluid of the glands that help him digest his meals frequently hardens into little grains in grinding the food. It's almost as if the saliva in our mouths, in addition to acting directly on the food, also made a new set of teeth for us!

Suppose we had a stomach like the earthworm, wouldn't it be fun? We could digest the biggest dinners at Thanksgiving and Christmas and picnics and birthdays. We could even eat apples without waiting for them to get quite ripe. Haven't you done it to your sorrow? And no stomachache and no mince-pie nightmares!

Why The Earthworm Never Has Nightmares

By the way, the earthworm, although he has his troubles like the rest of us, never _has_ nightmares. For one thing he has that stomach[11] and--a still better reason, perhaps--he never sleeps at night. Like the moths and the bats and the burglars and members of Parliament, he makes night his busy day.

[11] Just listen to this: "Worms," says Mr. Darwin, in that remarkable book of his, "are indifferent to very sharp objects, even rose thorns and small splinters of glass."

And, in other ways, while he is so much like the rest of us worms of the dust, his life differs from that of most people. For instance, he not only works by night while we work by day, and works underground while we work on top, but he takes his vacation in the Winter while we take ours in Summer. In that respect Mr. Earthworm is like the millionaires at Palm Beach; for in Winter he, too, goes in the direction we call south on the map--that is to say _down_.

But, as you say, it takes all kinds of people to make a world; including earthworms and millionaires!

Hide And Seek In The Library

Who was that in Mother Goose that went a-fishing "for to catch a whale"? Anyhow, there are fishworms so big that one might suppose they were made for catching whales. How long do you suppose they are, these big fishworms? A foot?

Pshaw! We have fishworms of our own a foot long. Two feet? More. Three feet? More. You look it up in the article on the earthworm in the "Britannica."

And how many kinds of earthworms do you suppose there are? You will be surprised to learn.

Also, you will find that the earthworms have relatives who live in the water all the time.

The article in the "International" tells why these modest neighbors of ours don't come to the surface in the daytime. That will be an interesting thing to know. Don't you think so?

And did you ever count an earthworm's rings? Other scientists have. (All live boys and girls are scientists; they want to _know_.) Try counting the rings of an earthworm and then compare your figures with those given in the article in the "International."

How many hearts do you suppose an earthworm has? You will find in the "International's" article they have a good many of what are sometimes called "hearts," and how different the earthworm's circulation system is from ours.

Does our saliva do for us anything like what it does for the earthworm; and our pancreatic juice?

Compare the earthworm's method of digging his subway with that of the armadillo. How do they differ in the way of using their noses?

Do you know how men dig subways; like those under New York City and Boston, for instance? Books that tell about this phase of human engineering and tell it in a very interesting way are "On the Battle-front of Engineering" ("New York's Culebra Cut") and "Romance of Modern Engineering" ("City Railways"), "Travelers and Traveling" ("How Elevated Roads and Subways Are Built").

Speaking of the earthworm's wedge and how he uses it, do you know that all of man's complicated machinery is the result of only a few simple mechanical principles combined; and that the wedge is one of the most important? Look up "_wedge_," "_machine_," "_simple machine_," etc., in the dictionary or encyclopaedia.

How does the earthworm's method of pushing his way in the world with the end of his nose compare with the way a root works along in the ground? (See Chapter X.)

The earthworm's neat way of disposing of the dirt he casts out reminds me of how the beaver handles dirt when he builds a canal, and the way of the ants in digging their underground homes. (Chapters VI and VIII.)

We have little brains in our finger-tips just as the earthworm has on the end of his nose. How much do you know about the little brains scattered through our bodies (_Ganglia_)?

You see the simple earthworm is the A, B, C of a lot of things; and even Mr. Darwin's famous book doesn't contain all there is to be learned about him in books and in personal interviews with Mr. Earthworm himself. A farm boy to whom the writer read the story of the earthworm, when asked how he thought the worm could turn in his burrow when it fits him so closely, said, "Why, he turns around in that little room at the end of the hall," thereby solving, as I think, a problem that puzzled Mr. Darwin, and which he left unsolved.

[Illustration: SINFUL TACTICS OF A SACRED BEETLE

The beetle pushing backward is the owner of the ball and is on his way--as he thinks--to his burrow. The other is altering the direction toward his own burrow. Fabre's book on the Sacred Beetle--the tumblebug of our fields and roadways--tells how the thing came out.]

Chapter VI

(June)

Go to the ant, thou sluggard; Consider her ways, and be wise.

--_Proverbs_ 6:6.

The Little Farmers With Six Feet

I don't believe I've ever heard anybody say anything against an angleworm; although not many people, even to this day, I'll be bound, realize what a useful citizen the angleworm is.

But now we come to a class of farmers that, as a class, are positively disliked; farmers that nobody has a good word for, that nobody wants for neighbors. The charge against them is that, like the man in the Bible, they are always reaping where they have not sown; always helping themselves to other people's crops--bushels of wheat, bushels of rye, tons of cotton, loads of hay and apples and peaches and plums; and nice garden vegetables; and even the trees in the wood lot. It is estimated, for instance, that the chinch-bug helps himself every year to $30,000,000 worth of Uncle Sam's grain; while other insects make away with 10 per cent of his hay crop, 20 per cent of mother's garden vegetables, $10,000,000 worth of father's tobacco; and the Hessian fly sees to it that between 10 and 25 per cent of the farmer's wheat never gets to mill.

"Yes, and sometimes it's 50-50 between the farmer and the fly," said the high school boy, who often spends his vacation with a country cousin.

Then there are insects that injure and destroy forest trees because they like to eat the leaves or the wood itself; and some 300 kinds of insects that make themselves free with other people's orchards.

I. Considering The Ant

But, as I said a few moments ago, it takes all sorts of people to make a world; and as there are good and bad citizens among men, so there are good and bad among insects. Indeed there are so many useful insects that help make or fertilize the soil by grinding up earth and burying things in it, that even this chapter, which is rather long, as you see, can't begin to tell about all of them. So suppose we give our space to a few by way of example, and then look up others in other books in the library.

Amount Of Work Done By Ants

First of all let us consider the ways of the ant (as the Bible tells us to). The ant's work may be said to take up where the earthworm leaves off. Mr. Earthworm, as we have seen, is a little fastidious about the kind of land he tills. Among other things, he is inclined to avoid sandy soil, while the ants will be found piling up their pretty cones of sand or clay as well as of black earth. And in some soils the ants do more important work than the worm that helped make Mr. Darwin famous. In the course of a single year they may bring fresh soil to the surface to the average depth of a quarter of an inch over many square miles. This not only helps to keep the farmer's fields fertile by adding fresh, unused earth, but enriches them by burying the vegetation--such as leaves and twigs and branches broken from dead trees by storms--so that it decays. This burying of vegetation is the very thing the good farmer does when he spreads his fields with manure from the barnyard, or when he ploughs under the stubble.

[Illustration: A HEAP OF GRIST FROM AN ANT SOIL MILL

Something of an ant-hill, isn't it? It is a foot high and measures nearly three feet across. You will find such ant hills in the Arkansas Valley in Colorado, where the photograph of this one was taken.]

Ants are very glad to do this for the farmer because it isn't any extra trouble for them. Their little heaps of fresh earth are thrown out in connection with the building of their homes. The mining ants dig galleries in clay, building pillars to support the work and covering them with thatches of grass. The red and yellow field ants are the masons. They first raise pillars and then construct arches between them, covering these arches with the loose piles of soil which we know as ant-hills. The carpenter-ants bore their cells in the dead limbs of trees, and the wood dust they make from them hurries on the process of returning these dead limbs to the soil. One kind of carpenter-ant covers its walls with a mixture of sawdust, earth, and spiders' webs. An ant in Australia builds its home of leaves fastened together with a kind of saliva. One kind of ant, whose calling card among scientific people is Formica fusca,[12] adds new stories to old houses as the colony grows; much as in the growth of cities and hamlets the buildings grow taller with the growth of the town. Just as men do, such ants first build the side walls and then the ceilings. As if these ants are working under contract and must get their job done by a certain time, two groups are employed on the ceiling at the same time, each group working toward the other from the opposite wall and meeting in the middle.

[12] In the world of science, the ant goes by her Latin name, _Formica_, and the whole family is known as the _Formicidae_. To a Roman boy _Formica_ simply meant "ant." _Fusca_ is also Latin, and means "dark"; so you can see this part of the story is about a species of dark ant. As a matter of fact he is dark brown.

[Illustration: THE DESERTED VILLAGE UNDER THE STONE

If Oliver Goldsmith had been as much interested in ants as was the French "Homer of the insect," Henri Fabre, he might have written of another kind of "Deserted Village," its "desert walks" and its "mouldering walls." This is a deserted village of ants. The little citizens that built it lived under a stone. When the stone was lifted it took the entire roof off the place.]

The Ant Who Didn'T Know His Trade

As you may suppose, this is real architectural engineering and no place for amateurs. I once saw a foolish worker starting a roof from the top of one of the side walls without paying any attention to the fact that the other wall was much higher. The result was he struck the middle of it, instead of joining it at the top. Another ant passing, possibly the supervising architect, saw what was going to happen. So what does he do but stop and tear down the other's work and build the ceiling over again!

"There! _That's_ the way to put in a ceiling," he seemed to say. "For goodness sake, where _did_ you learn your trade?"

Huber, the famous student of ants, saw two of these wonderful insects do the very same thing.

Sometimes the situation is such that it is necessary to build a very wide ceiling, so wide that it would fall of its own weight unless supported in some way. Then what would you do; that is, if _you_ were an ant?

"Why, I'd put up pillars to hold it."

That's exactly what the ants do; they put up pillars; but instead of using steel beams, as men do in this day of steel, the ant architects make pillars of clay--build them up with pellets, little clay bricks which they shape with their mandibles--their jaws.

But the ants seem to have some of the methods of steel construction, too; the use of girders and things. Ebrard, a French student of ants, tells how, when a certain roof threatened to fall, some Sir Christopher Wren of the ant world used a blade of grass as a girder, just as Sir Christopher in his day put in girders to support the roof of Saint Paul's Cathedral, and as men use steel girders to-day. The ant fastened a little mass of earth on the end of a grass stalk growing near to bend it over; then gnawed it a little at the bottom to make it bend still more, and finally fixed it with mud pellets into the roof.

But here's something that will make you smile! You have heard about the lazy man down in Arkansas with the hole in his roof? You remember he never mended it in dry weather because it didn't need it, and when it rained he _couldn't_ mend it on account of the rain!

Rainy-Day Work In The Ant World

Well, these _Formica fusca_ folks are as different from that Arkansas man as anything you could imagine. First of all, being ants, they are anything but lazy; secondly, they never put off needed work on their roofs on account of rain. In fact, they _choose_ the first wet day to do it. As soon as the rain begins they build up a thick terrace on the roof of the old dwelling, carrying in their jaws little piles of finely ground earth which they spread out with their hind legs. Then, by hollowing out this roof, they turn it into a new story. Last of all they put on the ceiling. You see the rain helps them in mixing their clay. There are ants that build up vaulted viaducts or covered ways, and they use clay for that.[13] They make the clay by mixing earth with saliva. Some of these viaducts reach out from the house--the ants' house--to their "cow" pasture.

[13] The scientific name for this particular kind of ant is _Lasius niger_.

[Illustration: AN ANT CARRYING ONE OF HER COWS]

You know about how ants keep cows, little bugs called aphids? The aphids feed on plants, and the clay viaducts protect the ants from their enemies and from the sun in going to and from the pasture; for this particular family of ants doesn't like the sun. They make clay sheds for their cattle, too. Here and there along the clay viaduct are large roomy spaces, cow-sheds, so to speak--where the little honey cows gather when they aren't feeding. Another kind of ant builds earth huts around its cow pastures. The large red ants (_F. rufa_), sometimes called "horse ants," build hills as large as small haycocks.

II. The Termites And Their Towers Of Babel

But speaking of big buildings, did you ever hear of a skyscraper a mile high? Well the home of the six-footed farmer I am going to tell you about now is as much taller than he is as a mile-high skyscraper would be taller than a man. The remarkable little creatures that build these skyscrapers are called "termites." Termites are also known as "white ants." This seems funny when we know that they are neither "ants" nor are they white. The young of the workers are white, to be sure, but the grown-ups are of various colors, and never milky white as they are when young. The termites were first called "white ants" in books of travel because the termites the travellers saw were the young people.

How Termites Are Like The Ants

The termites are really closer relatives of dragon-flies, cockroaches, and crickets than of the ants, but they do look a great deal like an ant, and they have many of the ways of the ants. As in the case of ants, all the members of one community are the children of one queen. The king lives with the queen in a private apartment. Sometimes--as with human royalties--the king and queen will have separate residences, but the termite royalties always live in the same house with their people; they are very democratic.

Some kinds of termites live in rotten trees, which they tunnel into, and that is their contribution to soil-making; while others build great, big solid houses of earth and fibres, mixed. These houses are called "termitariums," and are six, eight, ten, even twenty-five feet high; fully 1,000 times the length of the worker. Think of a man five feet high, and then multiply by 1,000, and you see you have got nearly a mile!

[Illustration: SKYSCRAPERS A MILE HIGH

"Some kinds of termites build great, solid houses of earth and fibres mixed. These houses are six, eight, ten, even twenty-five feet high, fully one thousand times the length of the worker. Think of a man five feet high and then multiply by one thousand, and you see you have got nearly a mile."]

These termite skyscrapers aren't much to look at on the outside, but inside they're just fine; they have everything the most particular ant could want. For instance, the termites are right up-to-date in their ideas about fresh air, their houses being well ventilated through windows left in the walls for that purpose. You can see the importance of this fresh-air system when you know there are thousands of termites under the same roof. They also have a sewage system for carrying off the water of the rains. And a fine piece of mechanical engineering the building of it is, too; for these "water-pipes" are the underground passages hollowed out in getting the clay to build the homes. The termites build their homes with one hand and dig the sewer with the other, so to speak.

The Thermostats For The Nurseries

The termitarium has as many rooms in it as a big hotel--oh, I don't know _how_ many--and they are all built around the chambers of the king and queen. Next to the royal apartments are the pantries, a lot of them, and they are all stored with food. In the upper part of the termitarium are the nurseries--many nurseries--for no one nursery could care for any such numbers of babies as the queen has. Between the nursery and the roof is an air-space, and there are also air-spaces on the sides and beneath. The nursery thus being surrounded by air, the eggs and, when they come along, the babies are protected from changes of temperature. It's the same principle that's employed in making refrigerators and thermos bottles. The rooms in which the eggs are kept are divided by walls made of fragments of wood and gum glued together. This mixture is a bad conductor[14] of heat or cold. And so the eggs are kept at an even temperature.

[14] A "bad" conductor is often a _good_ thing, as you'll see by looking it up in the dictionary.

While we cannot see any of the termite skyscrapers in the United States, because we have none of the species of termites that build them, we can see a member of the termite family. This is the common white ant that digs into joists of houses. On the outside of these same joists, and up in the attics of old farmhouses, if there happens to be a broken window-pane, or some other hole through which she can get in, you can see the nest of another tiller of the soil, the wasp. The mason-wasps or mud daubers are the most common. You will find their nests on the rafters of the barn when you go to throw down hay, or when you go into the corn-crib. They have all sorts of fancies--these wasps--about their clay homes and where to build them. Some build on the walls and some in the corners of rafters, others prefer outdoor life. Some want to live alone, others like society. What are known as "social" wasps sometimes build their nests in tiny hollows that they dig in the ground; others fasten their nests to the boughs of trees. The work of these wasps, from the farming standpoint, is useful not alone in grinding the soil, but helping to supply it with humus; for their nests are made of wood fibre, which they tear with their mandibles from gateposts, rail fences, and the bark of trees.

[Illustration: NESTS OF MASON-WASPS]

The carpenter-wasp is both a wood-worker and a clay-worker. He cuts tubular nests in wood and divides them by partitions. We think we're pretty smart, we humans, because we are always picking up ideas, but here's a creature, no bigger than the end of your finger, who has picked up an idea from the carpenter-bee, grafted it on his native trade of clay-worker, and made himself as nice and cosey a country place as you'd want to see!

About The Wasp, The Fox, And The Bumblebee

Here's another example of the same thing, this spreading of good ideas among the neighbors. It's about the fox, the digger-wasps, and the bumblebee. The fox can dig his own burrow when he has to, but if he finds somebody else's that he can use, he just helps himself--provided, of course, the owner isn't Brer Bear, or some other big fellow that Brer Fox doesn't care to have any words with. In the same way the digger-wasps make their own little burrows if they are obliged to, but prefer to help themselves to ones they find already made, although they don't drive anybody else out. They simply take possession of holes left by field-mice. The bumblebee does the same thing. The bumblebee digs a hole a foot or more deep, carpets it with leaves, and lines it with wax. Leading up to the home is a long, winding tunnel. As Bumblebeeville grows bigger there may be two or three hundred bees in one nest. As the bumblebee babies keep coming and coming, the burrow has to be dug bigger and bigger, to take care of them.

III. The House That Mrs. Mason Built

But the greatest of bee workers in the soil is the mason-bee. You can get an idea of what a useful citizen the mason-bee is when I tell you that one of the little villages of one species sometimes contains enough clay to make a good load for a team of oxen. Yet for all that, they might have gone on with their work for years and years to come--just as they have for ages in the past--and people wouldn't have thought much about it, if it hadn't been for some boys.

One time, in a village in southern France, a school-teacher, who was getting on in years, took his small class of farmer boys outdoors to study surveying--setting up stakes and things, you know, the way George Washington used to do. It's a stony, barren land--this part of France--and the fields are covered with pebbles. The teacher noticed that often when he sent a boy to plant a stake, he would stoop every once in a while, pick up a pebble and _stick a straw into it_! That's what it looked like! Then he would suck the straw.

Well, to make a long story short,[15] these pebbles had on them the little clay cells of the mason-bee. Mrs. Mason-Bee fills these cells with honey, lays an egg in the honey, and when the babies come along--don't you see? In other words, Mother Bee not only puts up their lunch for them, but puts them right into the lunch! This makes it convenient all around; for, like almost all insect mothers, Mrs. Mason-Bee is never there after the babies come.

[15] The whole story is told in the famous book, "The Mason Bee," by Henri Fabre. He was the teacher.

[Illustration: MASON-BEE CELLS AMONG THE ROCKS]

There were so many of these pebbles scattered over the plain, and the bees that were building new homes or repairing old ones flew so straight and so fast between the pebbles and a near-by road that "they looked like trails of smoke," as Fabre expresses it.

Now, you may well wonder why the bees flew clear over to that road to get dirt to build their nests when there was plenty of loose earth right at their own door-steps; right around the pebbles themselves. Isn't that queer?

Well, here's something that sounds stranger still. Mrs. Mason-Bee takes those extra trips because a roadway is so much harder to dig in! It's not because she needs the exercise, goodness knows--this busy Mrs. Mason-Bee--but because the hard earth of the roadway makes the strongest homes; that is, when she finally gets it dug out and worked up. And here's another thing that will seem odd at first; although the soil she thus works over must be dampened before she can plaster it into the walls of her home, she just won't use damp soil to begin with. Nothing will do her but dust, and dust that she herself scrapes from the