"... Time piles rock upon rock. The sea comes and goes with the passing geological ages. Unless other events intervened, my trilobite would have become interred within an ever deeper pile of sediments, to a depth possibly beyond the deepest coal seam, and buried into an obscurity from which it would never emerge. But often in geology that which is buried is destined to rise. Phases of mountain building throw up rocks that were once deep beneath the surface. The British isles have been through no fewer than three such phases since my trilobite scuttled about on the sea floor. The first of these — the — was responsible for disinterring my fossil."