PART I. 



PHYSIOGRAPHIC GEOLOGY. 



11. The systematic arrangement in the earth's features is every- 

 way as marked as that of any organic species ; and this system 

 over the exterior is an expression of the laws of structure beneath. 

 The oceanic depressions or basins, with their ranges of islands, and 

 the continental plains and elevations, all in orderly plan, are the 

 ultimate results of the whole line of progress of the earth ; and, by 

 their very comprehensiveness as the earth's great feature-marks, 

 they indicate the profoundest and most comprehensive movements 

 in the forming sphere, just as the exterior configuration of an 

 animal indicates its interior history. This subject is therefore an 

 important one to the geologist, although its facts come also within 

 the domain of physical geography. They lie at the top in geology 

 as its last results, and, thus situated, they constitute necessarily 

 the arena of the physical geographer. 



The following are the divisions in this department : — 



1. The earth's general contour and surface-subdivisions. 



2. System in the reliefs or surface-forms of the continental lands. 



3. System in the courses of the earth's feature-lines. 

 These topics are followed by a brief review of, — 



4. The system of oceanic movements and temperature. 



5. The system of atmospheric movements and temperature. 



6. The general law for the distribution of forest-regions, prairies, 

 and deserts. 



1. THE EARTH'S GENERAL CONTOUR AND SURFACE- 

 SUBDIVISIONS. 



12. The subjects under this head are — the earth's form ; the 

 distribution of land and water ; the depth and true outlines of the 



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