OPINIONS OF PREVIOUS WRITERS. 343 



plain evidence 5f the origin of these valleys. In the following discus- 

 sion of the literature it will be found that opinions of different kinds are 

 freely expressed, but that, with few exceptions, reasons for these opinions 

 are not stated. 



The first geologist to describe the region was Vanuxem,* who points 

 out that the accordance of the strata on the two sides of the valley pre- 

 cludes faulting, and that a subsidence of the.bottoni is too extravagant a 

 supjDOsition. He says : 



"The laken to the south of HelderJjerg range are an important and interesting 

 feature of the district, furnishing facts to show that the excavation of those at the 

 west end of the district (Cayuga, et cetera) was anterior to the dip of the rocks, et 

 cetera. . . . The whole of these lakes differ in no respect from the long parallel north 

 and south valleys of the same section, but in depth of water and apparently greater depth of 

 excavation." f 



Being puzzled by'the presence of rolled stones froai the north, he con- 

 cludes that the original flow was to the south, but the height of the 

 divide seemed to preclude that. He therefore concluded that the exca- 

 vation was accomplished before the dip was given to the strata. 



Vanuxem's discussion of the lakes ends with this remarkable truism, 

 which deserves to he kept prominentl}^ ])efore the mind in all investi- 

 gations : 



" Whatever he the real facts as to the flow of waters in opposite directions, patient 

 investigation in time, if true, will harmonize their results ; for truths only appar- 

 ently conflict with each other, the real conflict being solely in the minds of those 

 occupied with them." 



Dr Hall, speaking of the same lakes, says : X 



" The valleys of Seneca, Cayuga and Crooked lakes, Canandai<rua lake and others, 

 are of nearly equal width from one extremity to the other, with nearly i)erpen- 

 dicular banks above the water. It seems liardly possible that such channels could 

 -be excavated by the advancing and retiring, waves upon a coast which was gradu- 

 ally emerging from beneath an ocean." 



The same author says : § 



"They (the lakes) are all situated in valleys of erosion ; the rocky strata, with a 

 slight dip to the south, appearing on both sides." 



One of the first to describe the geology of the Great lakes after the 

 glacial hypothesis had become fairly well established was Dr Newberry, 

 and, although his descriptions were not of the region immediately in 



♦Geology of New York, Third District, vol. iii, 1842, p. 237. 

 fTiie italics are not in the original. 



J Geology of New York, Fourth District, vol. iv, 1843, p. 321« 

 g Ibid., p. 405. 



