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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Now a golf ball, however carefully it is made, is not always evenly made. It weighs a little more on one side than another; and the best golf balls, those which fly truest and farthest, are those which are most evenly made: so that we might say of them that the centre of their weight was exactly the same as the centre of the ball. If it is not, then the strains in the ball are always pulling it a little more out of shape; and the ball, as golfers say, flies badly. Now the earth is like a badly made golf ball. The centre of its weight, or, as we call it, the centre of gravity, is not quite at the centre of the earth. Moreover, owing to the enormous pressures which exist right through the earth, and which are by no means the same at every place inside the earth, but are, in fact, continually changing, owing to hundreds of causes, the whole of the earth's interior is in a state of unequal strain. What is the consequence that you would expect? Is it not that the earth should always be making efforts to adjust its weight, and, as it were, to distribute it evenly? It has been doing this for millions of years. It has not yet finished.