Project Gutenberg #20417
The Outline of Science, Volume 1
J. Arthur Thomson
1922Thomson's broad popular-science survey of astronomy, biology, and Earth science, prepared section by section from Project Gutenberg HTML.
Project Gutenberg #20417 Public domain in the United States Cover source Local typographic cover created for MojiMori from public-domain source metadata
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Until comparatively recent times, until, in fact, the full dawn of modern science, the tides ranked amongst the greatest of nature's mysteries. And, indeed, what agency could be invoked to explain this mysteriously regular flux and reflux of the waters of the ocean? It is not surprising that that steady, rhythmical rise and fall suggested to some imaginative minds the breathing of a mighty animal. And even when man first became aware of the fact that this regular movement was somehow associated with the moon, was he much nearer an explanation? What bond could exist between the movements of that distant world and the diurnal variation of the waters of the earth? It is reported that an ancient astronomer, despairing of ever resolving the mystery, drowned himself in the sea.