88 PEOCEEDINGS OF THE PRINCETON MEETING 



serpentine reliefs. A general classification of reliefs makes more clear the 

 dynamic and structural relations of the statenliths. The chronologic and 

 stratigraphic relations of the type example are also discussed. 



Eead in full from manuscript. 



Discussion 



Dr. E. O. HovEY remarked that the spine of Mont Pele could not be regarded 

 as the elevated or extruded plug of a volcano, but rather as the residue left 

 by explosions of vapor which carried away portions of an exuding dome of 

 lava which had solidified before it formed an ordinary flow. 



EROSIVE POTENTIAL OF DESERT WATERS 

 BY CHARLES KEYES 



i Abstract) 



Since the origin of the dominant relief features in arid lands has been so 

 long and persistently accounted for wholly on the hypothesis of general stream 

 corrasion — by a process differing only in degree from that displayed in a nor- 

 mal humid climate — we may, with advantage, quantitatively measure some of 

 the actual effects as presented under conditions of aridity, at the same time 

 noting some of the limitations which are necessarily placed on water action 

 by the exigencies of the desert. From consideration of the erosional modifica- 

 tions demanded by the special climatic conditions imposed by deficient rain- 

 fall, it follows that the gradational effects of the aqueous agencies must be 

 assumed at the outset to be far below that which is commonly expected of 

 them. Consideration is briefly given to the subjects of desert run-off, sheet- 

 flood action, through-flowing rivers, piedmont arroyos, mountain streams, in- 

 land seas, ephemeral lakes, playas, salinas, and ground-water level. 



Presented by title in the absence of the author. 



SUBMARINE TOPOGRAPHY IN GLACIER BAY, ALASKA i 

 BY LAWRENCE MARTIN 



(Abstract) 



During the summer of 1913 a National Geographic Society party studied 

 submarine topography in Glacier Bay, especially in Tarr, Muir, Queen, and 

 Tidal inlets. 



Tarr Inlet is 816 to 1,320 feet deep, in contrast with about 60O feet in outer 

 Glacier Bay. Nineteen years ago the thickness of Grand Pacific Glacier at 

 the international boundary, 12 miles from the glacier terminus of 1894, was 

 over 3,000 feet. The fiord is broadly U-shaped below, as above, sealevel. 

 The longitudinal section shows irregularities impossible for a river-carved and 



1 Presented by permission of Henry Gannett, chairman of the Research Committee of 

 the National Geographic Society. 



