The evolution of the scenery of these islands has been a long-continued process, wherein the chief part has been played by the air, rain, rivers, frost, and the other superficial agencies which are continually at work in wearing down the surface of the land. Each different kind of rock has yielded in its own fashion to the agents of destruction. Those rocks which have offered least resistance have been worn down into hollows and plains. Those of a more durable nature have been left standing up as ridges, hills, or mountains. The composition of the rocks has likewise governed the nature of the soils and the distribution of vegetation. Chalk, for instance, forms long ridges of grassy and bushless down. Sandy and gravelly tracts are marked by heather and pine-trees. Volcanic rocks often rise into isolated crags with verdant slopes below. Granite lifts itself into mountains and rocky moorlands, with cliffs, corries and 'tors' and long trails of naked scree. For the purposes of the present Lecture, I will arrange the scenery of this country in three leading types: I. LOWLANDS. II. UPLANDS. III. HIGHLANDS. These types are not always separable from each other by any definite lines of boundary. The lowlands, for example, include ranges of hills, and here and there gradually rise into uplands, which in turn occasionally mount into lofty, rugged ground that may well be called highland. Moreover, each type presents a number of local varieties, dependent on geological structure. Thus the English lowlands differ in many respects from the Scottish, and both from the Irish. The arrangement now proposed, though not strictly scientific, is for the proposed discussion convenient. We shall find, I think, that each of the three main types has had a perceptible influence on our literature, and not only so, but that even the local variations of each type have left their impress on our literary history. To treat the subject as fully as it deserves to be treated would require a course of lectures. I can only attempt to illustrate it by selecting a few instances from our poets where the relation that I wish to establish seems to be most readily perceptible. I. THE LOWLANDS OF BRITAIN. If a line be drawn across England from the mouth of the Humber through the Midlands to the Bristol Channel, it will divide the country into two sharply contrasted portions. To the west of it, the older, harder, and therefore more durable rocks rise into the high grounds of Wales, the Pennine Chain, and the Lakes. To the east of it, on the other hand, the younger, softer, and consequently more destructible, formations occupy the whole of the territory, giving a characteristic lowland topography to the districts that have been longest settled and cultivated, which include the greater portion of what is most familiar and typical in English landscape.