Читать книгу The Evacuation of England: The Twist in the Gulf Stream онлайн

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“I, a few moments past, called your attention to the fact that ‘if this least massive and most vulnerable type of structure has been subjected to repeated and considerable strains of elevation and depression, and strains recurrent at short intervals, then, without inspection, we know that its interior has been much shattered, and that it has undergone a progressive dilapidation.’

“Precisely such catastrophes are discovered in the history of the geological region now before us. The islands of the West Indies have been subjected to great changes of elevation. They have risen and fallen during the last geological age—the Tertiary—perhaps four times. In their rise they have gathered to themselves marginal extensions of land, now hidden beneath the ocean at comparatively slight depths, while they have at the same time doubtless become blended and unified into a great Antillean continent. This continent was dominated by volcanic protuberances whose growth upward, over accumulations of ashes, has been again symptomatic of undermining operations threatening later subsidence and submergence.