CHAPTER X.. The Structure of the Stratified Part of the Earth's

The structure of the stratified part of the earth's crust conveniently studied by the examination of a single formation--A coal-field selected for this purpose--Illustration of the principles necessary to such an investigation--The antiquities of a country of value in compiling its pre-historic annals--Geological antiquities equally valuable and more satisfactorily arranged--Order of superposition of stratified formations--Each formation contains its own suite of organic remains--The age of the boulder defined by this test from fossils--Each formation as a rule shades into the adjacent ones--Mineral substances chiefly composing the stratified rocks few in number--Not of much value in themselves as a test of age--The Mid-Lothian coal-basin--Its subdivisions--The limestone of Burdiehouse--Its fossil remains--Its probable origin--Carboniferous limestone series of Mid-Lothian--Its relation to that of England--Its organic remains totally different from those of Burdiehouse--Structure and scenery of Roman Camp Hill--Its quarries of the mountain limestone--Fossils of these quarries indicative of an ancient ocean-bed--Origin of the limestones--Similar formations still in progress--Coral-reefs and their calcareous silt--Sunset among the old quarries of Roman Camp Hill,

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