The Evolution of the Sciences 



streets of the town of Malmo have disappeared 

 into the Baltic Sea. 



Similar observations have been made in 

 every part of the world. In France Picardy is 

 gaining on the sea, while Normandy and some 

 parts of Brittany are sinking into it. Aunis and 

 Saintonge are rising, while Gascony is sinking. 



Some of these displacements may be ex- 

 plained by local or superficial causes, or by 

 modifications of the regular course of the tides. 

 But for many others a return to the hypothesis of 

 the internal fluidity of the globe is imperative. 

 An entirely solid mass, cooling and contracting 

 by jerks, gives way suddenly when its limit of 

 elasticity has been exceeded; only a fluid mass 

 can present the slow, continuous movements 

 proved to be universal by our observations. 



We might fancy that almost unawares we 

 have watched the work which, continuing for 

 thousands of years, has built up our great 

 mountain chains and hollowed out the abysses 

 of the sea. As the earth cools the fluid mass 

 within contracts more rapidly than the crust, 

 because fluids are always more expansible than 



solids, and for this reason the crust wrinkles like 



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