2o8 
Frank Carney 
It is observed (i) that the present day idea of the amount of 
glacial erosion does not differ much from estimates written thirty 
years ago; (2) that the method of, and the several lines of evidence 
of, ice-work were slowly understood and analyzed; and (3) that 
the most convincing evidence of deep valley erosion, the hanging 
valley, was described fifteen years ago, while the truncated spur 
characteristic was later recognized. 
Geological Department 
Denison University 
February, 1909 
