Читать книгу The Romance of Modern Geology. Describing in simple but exact language the making of the earth with some account of prehistoric animal life онлайн

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We will not at this moment stop to give further examples. We will only try to see whether there is any explanation which would make it possible to understand why there should be these slow upheavals and subsidences of the earth's surface. The chief and most important reason is that the earth is not so solid as it looks, and not so solid as it feels. It would be easier to realise this if, instead of living in a part of the earth like Great Britain, where there are very few earthquakes, we lived in Japan, or Central America, or in the archipelago of islands which runs from Java to Borneo and further south. In these places, where never a year passes but that the earth can be felt to quiver beneath one's feet, and where earthquakes which wreck houses are at least as common as eclipses of the moon, it is easier to believe that the earth is a rather shaky body; or, as scientific men would call it, a rather unstable body. But if, like those scientific men who take up the study of earthquakes, or "seismology," we equipped ourselves with instruments to measure or record earthquakes, we should perceive even in England that the earth is nearly always quivering. Something is always snapping or giving way in its interior, and producing trembling fits that sometimes can be felt hundreds of miles away, and sometimes can be felt all over the earth. There are on the average at least twenty earthquakes a year which make the whole of this round globe tremble.