38 I ROORESS : ITS LAW AND CAU8K. 



plcx structure, exposing many strata irregularly distributed, 

 raised to various levels, tilted up at all angles, must, undoi 

 the same denuding agencies, give origin to immensely mul 

 tiplied results ; each district must be differently modified; 

 each river must carry down a different kind of detritus ; 

 each deposit must be differently distributed by the en 

 tangled currents, tidal and other, which wash the con 

 torted shores; and this multiplication of results must 

 manifestly be greatest where the complexity of the surface 

 is greatest. 



It is out of the question here to trace in detail the genesis 

 of those endless complications described by Geology and 

 Physical Geography : else we might show how the general 

 truth, that every active force produces more than one 

 change, is exemplified in the highly involved flow of the 

 tides, in the ocean currents, in the winds, in the distribu 

 tion of rain, in the distribution of heat, and so forth. But 

 not to dwell upon these, let us, for the fuller elucidation 

 of this truth in relation to the inorganic world, consider 

 what would be the consequences of some extensive cos- 

 inical revolution say the subsidence of Central America. 



The immediate results of the disturbance would them 

 selves be suflicicntly complex. Besides the numberless 

 dislocations of strata, the ejections of igneous matter, the 

 propagation of earthquake vibrations thousands of miles 

 around, the loud explosions, and the escape of gases ; there 

 would be the rush of the Atlantic and Pacific Oceans to 

 supply the vacant space, the subsequent recoil of enormous 

 waves, which would traverse both these oceans and produce 

 myriads of changes along their shores, the corresponding 

 atmospheric waves complicated by the currents surrounding 

 each volcanic vent, and the electrical discharges with which 

 such disturbances are accompanied. But these temporary 

 effects would be insignificant compared with the permanent 

 ores. The complex currents of the Atlantic and Pacific 



