l893-] UPHAM — ESKERS NEAR ROCHESTER, N. Y. l8l 



ELECTION OF OFFICERS. 



The following officers were elected for the ensuing year : 



President, Herman L. Fairchild. 



First Vice-President, J. M. Davison. 



Second Vice-President, M. L. Mallory. 



Secretary, Arthur Latham Baker. 



Corresponding Secretary, Charles W. Dodge. 



Treasurer, J. Eugene Whitney. 



Librarian, Miss Mary E. Macauley. 



\ H. L. Preston. 

 Councillors, \ ^ -.xr ,tt 



' ( F. \\. Warner. 



In the absence of the author the following paper was read by the 

 President : 



ESKERS NEAR ROCHESTER, N. Y. 



a discussion of the structure and origin of the pinnacle 



hills.* 



By Warren Upham. 



contents. 



Page. 



The Area specially studied i8i 



Description of the Pinnacle Hills 182 



Relationship to the surrounding Country 187 



Altitudes in Rochester and its Vicinity 188 



Eskers in Pittsford 190 



Relationship to Drumlins and Terminal Moraines on the south 191 



Relationship to Glacial Movements 192 



Probable Origin of these Eskers 193 



Application of this E.xplanation to Eskers elsewhere 199 



The Area specially studied. 



On the southeastern border of Rochester, N. Y., a remarkable 

 esker series, named the Pinnacle hills, extends nearly four miles 

 from east-northeast to west-southwest, rising from an approximately 

 level country and forming the only conspicuous elevations of land 

 close to that city. Under the guidance of Mr. G. K. Gilbert, this 

 esker was examined by most of the geologists who attended the 

 meetings of the Geological Society of America and of Section E of 

 the American Association for the Advancement of Science in Roch- 

 ester last August, and on the following morning about an hour was 



*This paper was originally prepared for and read at the Ottawa meeting of the Geological 

 Society of America, December 29, 1892. 



