194 



of the Wabash Drainage System," in this volume. The westward wall 

 of ice along this Tippecanoe Gulf helps to explain the laking which was 

 due to the obstruction of drainage toward the west. 



Commenting on the theory proposed, Dr. C. R. Dryer mentioned that 

 the Iroquois Beach in New York is thickly strewn with bowlders in much 

 the same way as the Indiana belts mentioned. 



Aids in Teaching Physical Geography. 

 By V. F. Marsters. 



Harper's Ferry Sheet. 



The past decade has witnessed a growing interest in and a correspond- 

 ing advancement along rational lines in geography, now justly regarded 

 as a technical science. One of the pertinent reasons for this is that the 

 seeker after knowledge, long before the college is reached, is becoming 

 cognizant of the fact that the mere accumulation of geographical facts 

 does not constitute geographical knowledge in the scientific sense. To 

 know where the Blue Ridge is, is simply memorizing a fact; to know 

 lohat it is, and, still further, to find out for one's self something about 

 the sequential history of this topographic feature, constitutes real geo- 

 grapMc knowledge. The former calls for observation and the sole exer- 



