I have called this “the Geological Part,” and the name Geological comes from two Greek words meaning “a talk about the earth;” but now you know it in its English dress it will be easy to recollect it. Geology is then the study of the many kinds of rocks and fossils which makeup our World, but we must know something of the way in which they are placed. You may have noticed, if you have made many journeys to different parts of England or Wales, that the rocks or soils are very different in various places. Sometimes we find numerous chalk-pits, as in parts of Kent, or Sussex; if we go into Devonshire we may notice the very red colour of the soil and of the cliffs, especially near Sidmouth, Dawlish, and Teignmouth; in North Wales we find great quarries and hills of slate; while around London we see a great deal of clay used for making bricks, and called the London clay, as well as many pits in gravel so useful for making paths and mending roads, and in Kent and Sussex chalk cliffs and hills are common. Now after studying these various rocks all over our country, we find that there is a certain regular order in which they are found; some have been made a long time before others, and while most kinds contain some fossils, those found in the oldest rocks are much less like the living plants and animals than the fossils we find in the newer rocks. But you will want to know how it is that we can tell that one rock is older than another, when both appear at the surface of the earth. It would take a long time to make sure of this for ourselves, but it will be enough to say that the various cliffs, quarries, and railway-cuttings often show one kind of rock resting upon another, and these always occur in a certain order. Thus we never find the Chalk resting on the London Clay, but we constantly find the London Clay resting on the Chalk. And this is proved in another way, by deep well-borings. Underneath London many wells have been carried down right through the London Clay, and if only continued deep enough they always reach the Chalk. In the same way, the order of the other rocks has been ascertained in different parts of the country, by examining all the pits and quarries, and cliffs and cuttings, with the help of what knowledge can be obtained from deep mines and wells. You will now begin to wonder why the older rocks should appear at the surface. I have told you about earthquakes, and you will find that many dreadful earthquakes must in former times have ravaged our country. The reason why the old rocks come to the surface is because they have been lifted up sometimes violently, but more often very slowly. And the newer rocks which formerly rested on them have very often been quite washed away, either by the sea or by rivers and little streams which formerly acted upon them.