112 THE WONDERFUL CENTURY. CHAP. xn. 



catastrophe theory, and demonstrated, by a vast array of 

 facts and the most cogent reasoning, that almost every 

 portion of it was more or less imaginary and in opposi- 

 tion to the plainest teachings of nature. The victory 

 was complete. From the date of the publication of the 

 " Principles of Geology " there were no more English 

 editions of " The Theory of the Earth." 



Lyell's method was that of a constant appeal to the 

 processes of nature. Before asserting that certain re- 

 sults could not be due to existing causes he carefully ob- 

 served what those causes were now doing. He applied 

 to them the tests of accurate measurement, and he 

 showed that, taking into account the element of long- 

 continued action, they were, in almost every case, fully 

 adequate to explain the observed phenomena. He 

 showed that modern volcanoes had poured out equally 

 vast masses of melted rock, which had covered equally 

 large areas, with any ancient volcano; that strata were 

 now forming, comparable in extent and thickness with 

 any ancient strata ; that organic remains were being pre- 

 served in them, just as in the older formations; that 

 land was almost everywhere either rising or sinking, as 

 of old; that valleys were being excavated and mountains 

 worn away; that earthquake shocks were producing 

 faults in the rocks ; that vegetation was now preparing 

 future coal-beds; that limestones, sandstones, meta- 

 morphic and igneous rocks were still being formed; and 

 that, given time, and the intermittent or continuous 

 action of the causes we can now trace in operation, all 

 the contortions and fractures of strata, all the ravines and 

 precipices, and every other modification of the earth's 

 crust supposed to imply the agency of sudden revolutions 



