A HISTORY OF SCIENCE 



vastly more rapid and pronounced than those of a later 

 day; and to every clear thinker this truth also must 

 now seem axiomatic. 



Whoever thinks of the earth as a cooling globe can 

 hardly doubt that its crust, when thinner, may have 

 heaved under strain of the moon's tidal pull whether 

 or not that body was nearer into great billows, daily 

 rising and falling, like waves of the present seas vastly 

 magnified. 



Under stress of that same lateral pressure from con- 

 traction which now produces the slow depression of the 

 Jersey coast, the slow rise of Sweden, the occasional 

 belching of an insignificant volcano, the jetting of a 

 geyser, or the trembling of an earthquake, once large 

 areas were rent in twain, and vast floods of lava flowed 

 over thousands of square miles of the earth's surface, 

 perhaps, at a single jet; and, for aught we know to the 

 contrary, gigantic mountains may have heaped up their 

 contorted heads in cataclysms as spasmodic as even the 

 most ardent catastrophist of the elder day of geology 

 could have imagined. 



The atmosphere of that early day, filled with vast 

 volumes of carbon, oxygen, and other chemicals that 

 have since been stored in beds of coal, limestone, and 

 granites, may have worn down the rocks on the one 

 hand and built up organic forms on the other, with a 

 rapidity that would now seem hardly conceivable. 



And yet while all these anomalous things went on, 

 the same laws held sway that now are operative ; and a 

 true doctrine of uniformitarianism would make no 

 unwonted concession in conceding them all though 

 most of the imbittered geological controversies of the 



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