THE STORY OF NINETEENTH-CENTURY SCIENCE 



the same laws held that now are operative ; and a. true 

 doctrine of uniformitarianism would make no unwonted 

 concession in conceding them all though most of the 

 embittered geological controversies of the middle of our 

 century were due to the failure of both parties to realize 

 that simple fact. 



And as of the past and present, so of the future. The 

 same forces will continue to operate; and under oper- 

 ation of these unchanging forces each day will differ 

 from every one that has preceded it. If it be true, as 

 every physicist believes, that the earth is a cooling 

 globe, then, whatever its present stage of refrigeration, 

 the time must come when its surface contour will assume 

 a rigidity of level not yet attained. Then, just as sure- 

 ly, the slow action of the elements will continue to wear 

 away the land surfaces, particle b} r particle, and trans- 

 port them to the ocean, as it does to-day, until, compen- 

 sation no longer being afforded by the upheaval of the 

 continents, the last foot of dry land will sink for the 

 last time beneath the water, the last mountain -peak 

 melting away, and our globe, lapsing like any other 

 organism into its second childhood, will be on the sur- 



O 



face as presumably it was before the first continent 

 rose one vast " waste of waters." As puny man con- 

 ceives time and things, an awful cycle will have lapsed ; 

 in the sweep of the cosmic life, a pulse-beat will have 

 throbbed. 



