New England, and in a broad mass up the basin of Lake Ontario. 

 The direction in which it advanced is marked by the scratches upon 

 the rocks, the arrangement of boulders along its course, and its 

 terminal moraines. During the lapse of long eras of time the cold 

 grew more and more intense, until its maximum was finally reached. 

 The glaciers invaded regions further and still further south. No 

 longer confined to river channels or mountain gorges, it scaled hills 

 and ridges. A grand mer de glace covered the valley of the Genesee. 

 It filled Lake Erie, which is but eighty feet deep, to its bottom. It 

 pushed against the base of the ridge that bounds the basin of Lake 

 Erie on the south. It forced its way into the gorges at the mouths 

 of the streams of western Pennsylvania and northern Ohio ; which 

 streams, we have seen, discharged their waters northward through 

 the ridge into Lake Erie. As it ascended the chasm of the Cassa- 

 daga it carried away its rough sides, deeply filling them with an 

 earthy mass. It scaled the sides of the dividing ridge, and climbed 

 to the summits of the highest hills of Chautauqua County, spreading 

 deeply over all, highland and lowland, an unbroken sheet of material 

 called drift. As it forced its way up the channel of the Cassadaga 

 and through the passes between the hills of Cattaraugus, it seems 

 to have met a great glacier that had ascended the Genesee river and 

 crossed into the chasm formed by the upper Allegheny. Here these 

 streams of ice, controlled by the same laws that govern the action 

 of running water, but moving with far less velocity, seemed to have 

 formed a great eddy among the hills of Cattaraugus. There we 

 may see to great advantage the effects of the enormous power of 

 these mighty glaciers as they opposed each other like currents of 

 water, in the wonderful sculpturing of the hills and in the carving 

 of the valleys. 



The physical features of Chautauqua County were greatly 

 changed when the glaciers left them. The landscape was also quite 

 different at the close of the ice period from what it is now. There 

 were dumped everywhere confused and unfertile heaps of loose 

 earth, gravel and stones. Huge boulders lay scattered at intervals 

 entirely above the drift and over the whole surface. They lay 

 thickest along the northern face of the ridge and near its brow in 

 the town of Portland, and in the other ridge towns of the county. 

 They some time seem to have been arranged in windrows, and often 

 rest in such high relief above the drift, lying wholly upon its surface, 

 as to lead to the conclusion that they were brought by icebergs. It 

 is quite probable that they were transported by glaciers, but instead 

 of being moved along beneath their under surface like common drift, 

 they were borne upon the upper portions of the glaciers from the 

 granite regions of Canada, and as the ice melted away they were 

 left upon the surface as we find them now. 



44 



