Chapter X

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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