Í9I3-] ORTMAXX— THE ALLEGHENIAN DIVIDE. 389 



Potomac drainage: 



/4« = Antietam Creek. 5. B. = South Branch Potomac 



River. 

 Con = Conococheague Creek. To — Tonoloway Creek. 



A r . 5. = North Branch Potomac f<F = Wills Creek. 

 River. 



James drainage: 



N = North River (headwaters called: Calf Pasture River). 

 RF = Rockfish Creek. Riv = Rivanna River. 



Roanoke drainage: 

 N. F. = North Fork Roanoke River. 



Holston drainage: 



ffofoíon = North Fork Holston 5". F. = South Fork Holston River. 



River. 

 M. F. = Middle Fork Holston River. 



EXPLANATION OF PLATE XIII. 

 Profiles of Rivers. 



Fig. i. Profile up from Pittsburgh, Pa., along Allegheny River, Mahon- 

 ing and Little Mahoning Creeks to Divide, and thence down along Cush 

 Cushion Creek, West Branch Susquehanna, and Susquehanna River to Havre 

 de Grace, Md. (sea level). 



Between Curvensville and Keating the river has not been accurately sur- 

 veyed. 



Compiled from : U. S. Geol. Surv. Atlas Sheets, and Hoyt and Ander- 

 son, 1905, pi. 28 and 29. 



Fig. 2. Profile from a little above McKeesport, Pa., up the Mononga- 

 hela and its tributaries (Youghiogheny, Cheat and Shavers Fork, Tygart 

 Valley River, West Fork River) to the Divide, and thence down the South 

 and North Branch and the Potomac River, to Washington, D. C. 



The sources of Shavers Fork and South Branch Potomac are about 

 twenty miles apart. On account of the exaggerated vertical scale, the head- 

 waters of all rivers appear much longer than they actually are. 



Compiled from : U. S. Geol. Surv. Atlas Sheets, and Bolster, 1907, pi. 5 

 and 6. 



