rl06 NEW YORK STATE MUSEUM 



reference to the higher, and earlier channels cut by the overflow 

 of the glacial waters. 



3 In westward extension of the study, a large area was 

 examined in Cattaraugus and Chautauqua counties. 

 - The glacial phenomena are so varied and complex, specially in 

 the last two districts, and the territories so large that it was not 

 poeeible in one season to complete the study. However, it is 

 desirable to describe some of the phenomena with considerable 

 fulness and detail in this report. The districts will be taken up 

 in the order given above. 



1 THE IROQUOIS SHORE LINE 

 Introduction, historical 



The ancient, high-level beach phenomena in the Ontario basin 

 were noted by the early settlers and travelers, and their character 

 as beaches was generally recognized. They were the subject of 

 study and printed notice by Thomas Roy (1887), Lyell, Hall and 

 others long before their glacial relationship was recognized. The 

 earliest description of these ancient shores in New York state 

 was by Prof. James Hall, in the Geology of Neiv York; 4th geologi- 

 cal district, p. 348-51. In hie chapter on lake ridges he marshals 

 the facts in proof of their beach origin, and describes their form 

 and structure. He also discusses briefly their relationship to the 

 land surfaces of central New York, and their hlght above Lake 

 Ontario. The elevation of the beaches he attributed to changes 

 in land level, and admitted the possibility of their marine origin. 

 As he was personally acquainted with only the stretch between 

 Niagara and Sodus, he did not recognize the deformation of the 

 shore line from the horizontal. 



In recent years these beaches have been traced in New York 

 state by Gr. K. Gilbert, and in Canada by J. W. Spencer. It has 

 been demonstrated, specially through the work and writings of 

 Mr Gilbert, that the beaches are the shore of a great lake which 

 had its outlet at Rome N. Y. to the Mohawk valley, and was held 

 up to that level by the continental ice sheet, which covered and 

 blocked the St Lawrence valley. The name Iroquois was given 



