8 



OUTLINES OF GEOLOGY. 



perature has taken place for more than 2000 years, There 

 are, however, some who maintain that the state of equilibri- 

 um between solar and terrestrial radiation has not yet been 

 reached, and that the earth is still decreasing in temperature, 

 although so slowly that it cannot be detected by the method 

 to which we have referred. 



III. 



OF THE DISTRIBUTION OF LAND AND WATER ON THE 

 SURFACE OF THE GLOBE. 



12. The solid crust of our globe is far from being level, 

 but presents a succession of prominences and cavities irregu- 

 larly distributed. The deepest of these cavities communis 

 cate with each other, and are filled with a great mass of 

 water, which we call the ocean. This is of such extent as 

 to cover, at least, three-fourths of the surface of the globe. 

 We distinguish different portions of this mass by names, al- 

 though there is no precise limit between these several portions, 

 and although to a general and systematized view the sur- 

 face of the globe presents the aspect of a single great ocean, 

 in which are situated two great and an infinite number of 

 small islands. The two great islands are the Old and New 

 Continents ; of the smaller islands New Holland is the most 

 extensive. 



13. In order to exhibit this arrangement of the surface 

 of the globe in the clearest light : — take a terrestrial globe, 

 elevate its southern pole 50°, and bring New Zealand to the 

 meridian, the hemisphere which now lies above the horizon 

 is wholly covered with water, except many small islands, 

 the southern extremity of South America, New Holland, and 

 the Indian Archipelago. In the opposite hemisphere and im- 

 mediately adjacent to the part above the horizon, are por* 



