COAL AN INTER-GLACIAL FORMATION.
Climate of Coal Period Inter-glacial in Character.—Coal Plants
indicate an Equable, not a Tropical Climate.—Conditions
necessary for Preservation of Coal Plants.—Oscillations
of Sea-level necessarily implied.—Why our Coal-fields
contain more than One Coal-seam.—Time required to form a
Bed of Coal.—Why Coal Strata contain so little evidence of
Ice-action.—Land Flat during Coal Period.—Leading Idea of the
Theory.—Carboniferous Limestones 420