6/2 MARIUS R. CAMPBELL 



latter stream, hence we conclude that the prevailing tilt of the 

 surface has been toward the northwest and away from the Cum- 

 berland River. 



Some of the peculiarities cannot now be satisfactorily 

 explained even on this basis, but the writer believes that it is 

 because of the lack of reliable data and of the complexity of the 

 problem. They are doubtless due to the same cause, but in all 

 probability it has not always acted in the same place, nor in the 

 same direction. 



(3) REMOTE CHANGES SHOWN IN THE STREAMS OF THE ATLAN- 

 TIC SLOPE. 



Throughout the gulf coast of the Atlantic slope there are 

 numerous examples of migration of divides and the consequent 

 unsymmetrical condition of the stream basins. The limits of 

 this paper will not permit of a full discussion, so only a few can 

 be mentioned. 



{^a) Chattahoochee River. — The most pronounced case of the 

 kind is the encroachment of the Atlantic streams upon the Chat- 

 tahoochee River. From Columbus, Georgia, to its headwaters, 

 the drainage basin of this river is limited almost entirely to its 

 northwestern side. Figure 1 2 shows the arrangement of the drain- 

 age lines in the region about the headwaters of the Chattahoo- 

 chee River. A B is the Etowah River ; C D, the Chattahoochee 

 River ; G, the Oconee River ; //, the Broad River ; and K L, the 

 Savannah River. The Atlantic streams, or those flowing toward 

 the southeast, have symmetrical basins in which are developed 

 beautiful dendritic drainage lines. The small branches are num- 

 erous and have straight, regular courses at right angles to the 

 main line of the Chattahoochee River This arrangement of the 

 minor drainage lines is indicative of a strong southeastward 

 slope of the surface. These minor streams have not only 

 arranged themselves parallel with the line of greatest slope, but 

 they have also extended their courses headwards, until at one 

 point they are within a mile of the Chattahoochee River and at 

 least 100 feet below it. 



