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

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“But at the period of this greatest elevation, when this tropical region assumed individual independence, and embodied a geognostic importance comparable to the vast continents it lay between—at this time—the Isthmus of Panama did not exist, and through a wide water-way the Atlantic mingled its tides with those of the Pacific.

“We are thus led to believe that as between the West Indian terranes and the neck of land now embraced in the Isthmus of Panama, we have a relation of Isostacy.’”

The speaker, armed with this formidable verbal equipment of attack upon his audience, had walked to the front of the platform, and, harboring some unusual confidence in his powers, had deserted his manuscript. Isostacy, he had realized, possessed probably unqualified novelty, and by way of assurance, lest its terrors might empty the hall, he assumed a colloquial relation to his dazed hearers, and offered an explanation of this unexpected mystery. “Isostacy,” he resumed, “is simply this: Equilibrium. It is the maintenance of average level—as if one part of the earth’s surface was pushed up, above a mean level, then the requirements of Isostacy would depress another part, below it. We can also call it the adjustment of a changing load, as if through depression, from the dumping upon the floor of the ocean of a great amount of sediment, derived from the land surface of the earth, neighboring areas of the land of the oceanic floors were raised. Two contiguous regions might—and,” the lecturer turned directly toward the President, who in his own earnestness of attention had elbowed himself round into a direct line with Mr. Binn, “in the case of the West Indian continent and the Isthmus of Panama, have maintained between them, an up and down reciprocity of movement, as, when one was up, the other was down, and vice versa.”