Let us now visit some quarries in East Cheshire. We shall find considerable difficulty in reaching some of them. It will be necessary to get permission from the owners of the quarries, put on a special suit of clothes, enter an iron cage, and descend many hundred feet perhaps into the depths of the earth's surface until we find ourselves—in a coal-mine!

Unlike the New Red Sandstones, which are found for the most part in flat horizontal beds, the coal beds slope downwards from east to west. This is due to the uplifting of the East Cheshire hills, which we shall presently explain. When this uplift took place, the coal beds, which were originally flat, became raised in the east and equally lowered in the west. When the sea flowed over them they became covered by sandy deposits of such a thickness that in the greater part of Cheshire the coal cannot be reached. The earliest sands laid down formed what are called the Permian rocks, and the later layers the New Red Sandstone series mentioned in the last chapter. The Permian rocks may be well seen at Stockport, in the river beds of the Tame and the Goyt which have cut their way through them. In the strip of country between Stockport and Macclesfield, and again on the south-eastern borders of Cheshire, the upturned edges of the coal beds have been left exposed so that the coal is near the surface and can be easily extracted.

Coal consists of the vegetable remains of forest trees and their undergrowth. If you look at a lump of coal you will see that it has been pressed down into thin layers like the leaves of a book. When these layers are split apart there are often found the fossil remains of leaves and roots of trees, fronds of ferns, seed-cones and stems of plants which grew in the forests. Some of these, particularly the ferns, are often of great beauty. You may see a number of these 'coal pictures' in the Vernon Park Museum at Stockport. Here too you will find portions of the actual trunks of trees that have been dug up just where they stood when the seas flowed over them.

You may learn even to distinguish different varieties of these forest trees, just as you are able to distinguish the oak and the beech and the elm of to-day. Latin names such as Sigillaria, Lepidodendron, and Salisburia have been given to them. The most beautiful of all is a Maidenhair Tree-fern. The Calamites was a huge 'Horse-tail' plant of which you may find small varieties to-day on banks and in hedgerows.

On the coast of Wirral, between Meols and New Brighton, are the remains of a forest which has only in very recent years been covered by the sea. Boys who live in this neighbourhood may have heard their parents tell of the stumps of tree-trunks sticking out through the sands when the tide was low. This shows that the land is continually undergoing changes, at one time being raised above the seas, at another time sinking beneath the waves.

The beds or 'seams' of coal vary in thickness from a thin film to several yards, and are separated from one another by layers of hard clays and flagstones. From the flagstone beds are obtained the square slabs with which the pavements of our towns and cities are laid. In many of the quarries near the Cheshire coal-field you may watch the workmen cutting and shaping these stones.

The beds of clays and seams of coal make up what are called the 'Coal Measures'. These in their turn rest upon a foundation of hard rock, harder than any we have yet examined, called Millstone Grit or Gritstone. Boys who live in the hilly parts of East Cheshire are very familiar with it, for very probably the houses in which they live and the churches and chapels where they worship have been built of this stone. It is composed of coarse sand and grit, and, like the red sandstone, is a waterlaid deposit several thousand feet in thickness. The Pennine Hills, on the borderland of Cheshire and Derbyshire, are covered with Millstone Grit, which has been thrust upwards by the crumpling and arching of the rocks beneath it.

Below the Gritstone are still older rocks of a different character called the Limestone series. The uppermost beds contain layers of a sandy substance called Yoredale sandstones. Mixed with them are layers of shale, a dark bluish grey clay that crumbles into thin fragments when crushed with the hand, and thin seams of limestone and, occasionally, of coal. These are the oldest rocks that are found anywhere in Cheshire. You may see them in the hills east of Macclesfield and Congleton and the higher parts of Longdendale. Below these beds is a mass of Mountain Limestone which has been forced upwards into an arch by tremendous pressure of rocks from either side, and has lifted up the Gritstone above to a height of nearly two thousand feet. In this way the highlands of East Cheshire, and indeed the whole of the Pennine Chain, have been formed. The Mountain Limestone, which consists almost entirely of animal remains, especially shells and corals, extends right under the highest hills of Cheshire, and comes to light in the cliffs of the beautiful dales of Derbyshire. Only at one spot, a quarry near Astbury, does it appear at the surface in Cheshire.

The Coal Measures, Millstone Grit, Yoredale sandstones, and Mountain Limestone make up what geologists call the Carboniferous or Coal-bearing series, so called because in England our chief supplies of coal are obtained from this group of rocks.

But we should have to dig deeper even than the Mountain Limestone before we could reach the original surface of the earth in Cheshire. Long ages ago, ages so distant that not even the most learned men of science can reckon them, our earth was a globe of fiery molten rock. As the surface gradually cooled it became wrinkled, as a baked apple will when taken from an oven. Water collected in the hollows into which fragments of rock were washed down from the ridges, and thus the waters were raised and formed into seas and lakes. But we shall not find any of these rocks in Cheshire, though you may see them in great masses in the mountains of Cumberland and Wales, where they have been forced upwards by the violent movements always at work in the interior of the earth. It is of these molten rocks that the mass of stone which was brought by the ice from Cumberland and left on Eddisbury Hill is composed.