to a layer of limestone, would you not say the same?  And if you found that limestone full of shells and corals, dead, but many of them quite perfect, some of the corals plainly in the very place in which they grew, would you not say—These creatures must have lived down here before the coal was laid on top of them?  And if, lastly, below the limestone you came to a bottom rock quite different again, would you not say—The bottom rock must have been here before the rocks on the top of it?

And if that bottom rock rose up a few miles off, two thousand feet, or any other height, into hills, what would you say then?  Would you say: “Oh, but the rock is not bottom rock; is not under the limestone here, but higher than it.  So perhaps in this part it has made a shift, and the highlands are younger than the lowlands; for see, they rise so much higher?”  Would not that be as wise as to say that the bottom of the pond was not there before the pond mud, because the banks round the pond rose higher than the mud?

Now for the soil of the field.

If we can understand a little about it, what it is made of, and how it got there, we shall perhaps be on the right road toward understanding what all England—and, indeed, the crust of this whole planet—is made of; and how its rocks and soils got there.

But we shall best understand how the soil in the field was made, by reasoning, as I have said, from the known to the unknown.  What do I mean?  This: On the uplands are fields in which the soil is already made.  You do not know how?  Then look for a field in which the soil is still being made.  There are plenty in every lowland.  Learn how it is being made there; apply the knowledge which you learn from them to the upland fields which are already made.

If there is, as there usually is, a river-meadow, or still better, an æstuary, near your town, you have every advantage for seeing soil made.  Thousands of square feet of fresh-made soil spread between your town and the sea; thousands more are in process of being made.

You will see now why I have begun with the soil in the field; because it is the uppermost, and therefore latest, of all the layers; and also for this reason, that, if Sir Charles Lyell’s theory be true—as it is—then the soils and rocks below the soil of the field may have been made in the very same way in which the soil of the field is made.  If so, it is well worth our while to examine it.

You all know from whence the soil comes which has filled up, in the course of ages, the great æstuaries below London, Stirling, Chester, or Cambridge.

It is river mud and sand.  The river, helped by tributary brooks right and left, has brought down from the inland that enormous mass.  You know that.  You know that every flood and freshet brings a fresh load, either of fine mud or of fine sand, or possibly some of it peaty matter out of distant hills.  Here is one indisputable fact from which to start.  Let us look for another.

How does the mud get into the river?  The rain carries it thither.

If you wish to learn the first elements of geology by direct experiment, do this: The next rainy day—the harder it rains the better—instead of sitting at home over the fire, and reading a book about geology, put on a macintosh and thick boots, and get away, I care not whither, provided you can find there running water.  If you have not time to get away to a hilly country, then go to the nearest bit of turnpike road, or the nearest sloping field, and see in little how whole continents are made, and unmade again.  Watch the rain raking and sifting with its million delicate fingers, separating the finer particles from the coarser, dropping the latter as soon as it can, and carrying the former downward with it toward the sea.  Follow the nearest roadside drain where it runs into a pond, and see how it drops the pebbles the moment it enters the pond, and then the sand in a fan-shaped heap at the nearest end; but carries the fine mud on, and holds it suspended, to be gradually deposited at the bottom in the still water; and say to yourself: Perhaps the sands which cover so many inland tracts were dropped by water, very near the shore of a lake or sea, and by rapid currents.  Perhaps, again, the brick clays, which are often mingled with these sands, were dropped, like the mud in the pond, in deeper water farther from the shore, and certainly in stilt water.  But more.  Suppose once more, then, that looking and watching a pond being cleared out, under the lowest layer of mud, you found—as you would find in any of those magnificent reservoirs so common in the Lancashire hills—a layer of vegetable soil, with grass and brushwood rooted in it.  What would you say but: The pond has not been always full.  It has at some time or other been dry enough to let a whole copse grow up inside it?

And if you found—as you will actually find along some English shores—under the sand hills, perhaps a bed of earth with shells and bones; under that a bed of peat; under that one of blue silt; under that a buried forest, with the trees upright and rooted; under that another layer of blue silt full of roots and vegetable fibre; perhaps under that again another old land surface with trees again growing in it; and under all the main bottom clay of the district—what would common sense tell you?  I leave you to discover for yourselves.  It certainly would not tell you that those trees were thrust in there by a violent convulsion, or that all those layers were deposited there in a few days, or even a few years; and you might safely indulge in speculations about the antiquity of the æstuary, and the changes which it has undergone, with which I will not frighten you at present.

It will be fair reasoning to argue thus.  You may not be always right in your conclusion, but still you will be trying fairly to explain the unknown by the known.

But have Rain and Rivers alone made the soil?

How very much they have done toward making it you will be able to judge for yourselves, if you will read the sixth chapter of Sir Charles Lyell’s new “Elements of Geology,” or the first hundred pages of that admirable book, De la Bêche’s “Geological Observer;” and last, but not least, a very clever little book called “Rain and Rivers,” by Colonel George Greenwood.

But though rain, like rivers, is a carrier of soil, it is more.  It is a maker of soil, likewise; and by it mainly the soil of an upland field is made, whether it be carried down to the sea or not.

If you will look into any quarry you will see that however compact the rock may be a few feet below the surface, it becomes, in almost every case, rotten and broken up as it nears the upper soil, till you often cannot tell where the rock ends and the soil begins.

Now this change has been produced by rain.  First, mechanically, by rain in the shape of ice.  The winter rain gets into the ground, and does by the rock what it has done by the stones of many an old building.  It sinks into the porous stone, freezes there, expands in freezing, and splits and peels the stone with a force which is slowly but surely crumbling the whole of Northern Europe and America to powder.

Do you doubt me?  I say nothing but what you can judge of yourselves.  The next time you go up any mountain, look at the loose broken stones with which the top is coated, just underneath the turf.  What has broken them up but frost?  Look again, as stronger proof, at the talus of broken stones—screes, as they call them in Scotland; rattles, as we call them in Devon—which lie along the base of many mountain cliffs.  What has brought them down but frost?  If you ask the country folk they will tell you whether I am right or not.  If you go thither, not in the summer, but just after the winter’s frost, you will see for yourselves, by the fresh frost-crop of newly-broken bits, that I am right.  Possibly you may find me to be even more right than is desirable, by having a few angular stones, from the