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.

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 encyclopædia 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.")

CHAPTER IV

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.

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.

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:

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

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.

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.

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.

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.

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.

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!

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.

CHAPTER V

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 Cæsar did, captures the whole of England—all the best parts of it—and then, unlike Cæsar, 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!

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.

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.