GEOLOGICAL SEASONS. 195 



have discovered, in high eccentricity, a cosmical cause ca- 

 pable of putting in action such terrestrial agencies as must 

 necessarily lead to the extensive glaciation of the north- 

 ern and southern hemispheres alternately. 



This conclusion affords us a glimpse into the possible 

 future of the course of civilization. When, in some re- 

 mote coming age, the softening influence of the Gulf 

 Stream shall be transferred from the western shores of 

 Europe to the eastern shores of Patagonia, the climate of 

 Great Britain will return to the condition determined by 

 the fundamental astronomical factors of climate. What 

 this condition is may be understood from the present cli- 

 mates of other regions in the same zones of latitude, and 

 not influenced by oceanic currents, Athabasca, Labrador, 

 Tobolsk in Siberia, and Central Kamtchatka. Then the 

 Falkland Islands and Tierra del Fuego will acquire the 

 present climate of Great Britain. London will have dwin- 

 dled to a whaling station in the icy seas of the far north. 

 Another London will have sprung up on the genial shores 

 of Falkland; another Paris will have been built on the 

 Straits of Magellan, and all the centers of human civili- 

 zation and industrial activity will have been transferred 

 to the southern hemisphere. The lands of the north will 

 have been borne down by a load of arctic ice, beneath the 

 cold waters of the North Atlantic, and the now submerged 

 continents of the south will have been disburdened of their 

 secular glaciers, so as to rise up and offer a new theater 

 for the activities and further progress of the human 

 species. 



The present theory of glacial periods affords us a clew 

 to the solution of the difficult problem of geological time. 

 The epochs of high eccentricity are susceptible of deter- 



