202 THE BOOK OF NATURE STUDY 



bricks; petroleum; lime for mortar, cement, and smelting; 

 sandstone and grits for building, paving, and the making of 

 millstones and grindstones; as well as ores of lead and 

 zinc. The typical moorland landscape of the Pennine Chain 

 is due to the outcrop of the grit beds of the Millstone Grit, 

 while the limestone country is either grass-covered and cut into 

 abrupt valleys, once perhaps caves, or is barren and terraced, 

 scarred with great cracks running along the joints widened by 

 solution, and waterless because the drainage finds its way down 

 these cracks into caves and underground channels (Figs. 33 and 74). 

 The Coal Measure landscape was doubtless once beautiful, and is 

 even now at times interesting when forest covered, as much of it 

 doubtless originally was. 



The Permian Rocks consist of sandstones, conglomerates, and 

 breccias, generally stained deep red with oxide of iron. There is 

 often present a peculiar limestone containing magnesium carbonate 

 as well as calcium carbonate. It yields few fossils, those present 

 belonging to few species. These are of marine type, but stunted 

 and dwarfed in development, as though living in a most un- 

 favourable environment. It is generally thought that this 

 indicates formation in a salt lake in a dry climate. This is 

 borne out by the nature and unfossiliferous character of associated 

 deposits, by the nature of the scree-like breccias; and by com- 

 parison of the British rocks with marine deposits of this age 

 known on the continent of Europe. The most important new- 

 comers in the life are the earliest reptiles. The rest of the 

 fauna is an impoverished descendant of that of the Carboni- 

 ferous without any remarkable new ingredients. The plants are 

 the last survivors of Carboniferous types with a few Cycads. 

 But in Europe outside Britain, in addition to the Palaeozoic types 

 of life, there are found also the first representatives of those 

 types which are soon to become abundant and give its character 

 to the Mesozoic life. The sandstones and magnesian limestones 

 are used for building, but there is little else of economic interest, 

 and the landscape of the rocks calls for no remark. In a few 

 places there are volcanic rocks of this date, but this was the 

 last effort of the Palaeozoic volcanoes, and the country was quite 

 quiescent in this respect during the Mesozoic Era. 



