274 ROCHESTER ACADEMY OF SCIENCE. [Feb. I4, 



The following officers were elected for the year 1899 : 



President, Herman L. Fairchild. 



First Vice-President, Geogre W. Goler. 



Second Vice-President, Charles Wright Dodge. 



Secretary^ Montgomery E. Leary. 



Corresponding Secretary, Chas. Wright Dodge. 



Treasitrer, Joseph E. Putnam. 



Librarian, Miss Florence Beckwith. 



^ .J J f Emil Kuichling, ) ,., 

 Councillors, \ „ \ iintil 1002. 



\ J. M. Davison, i ^ 



The President read a paper illustrated by lantern views, maps 

 and charts, on 



THE PREDECESSORS OF NIAGARA. 

 By H. L. Fairchild. 



(Abstract.)* 



The ancient streams which may be regarded as the ancestors of 

 Niagara were hundreds of miles from the present cataract. These 

 extinct rivers have left remarkable gorges across the ridges separating 

 the north and south valleys of Skaneateles, Otisco, Onondaga, Butter- 

 nut and Limestone, and they lie along a line adjoining the villages of 

 Marcellus, South Onondaga, Jamesville, High Bridge and Mycenae. 

 To trace Niagara's ancestry back to the time when it is possible to 

 discover any trace of the course of the original waters, it is necessary 

 to go back to the glacial period. The last great invasion of ice buried 

 all of New England, all of New York State, except a small area near 

 Salamanca, all of the basins of the Great Lakes and the Mississippi 

 Valley as far south as nearly to the mouth of the Ohio river. 



This ice body, some thousands of feet in thickness, uncovered the 

 land it had invaded, not by general melting of its surface, but by the 

 slow recession of its front. The summer floods from the rainfall and 

 the ice melting carried immense quantities of gravel down the south- 

 leading valleys and filled them deeply with the detritus. When the 

 ice front retreated to the north side of the divide separating to-day the 

 northward drainage of the St. Lawrence from the southward drainage 

 of the Mississippi and Susquehanna, the waters were impounded be- 

 tween the ice front and the north-sloping land surfaces. 



♦Fuller discussion of the subject may be found in Btill. Geol Soc. Am.VoX. lo, pp. 27-68; 

 Am. Jo2ir. Sci., Vol. 7, pp. 249-263 ; 20th An. Rep. Ne7v York Slate Geologist, 1900, pp. H2-130. 



