148 Agricultural Experiment Station, Ithaca, N. Y. 



Line to Hamburg, I Lave not found a single rock cliff. In some 

 cases wells have reached roct near the front edge of the gravel 

 terrace, suggesting the possibiUt}'^ of such cliffs veneered over with 

 gravel which has slipped down from above. This would be 

 possible only with low rock cliffs ; and we may therefore conclude 

 that in this part of the shore line there are no wave-cut cliffs which 

 are at all comparable in size to those of the present lake shore. 

 "Whether there are any wave-cut cliffs of gravel I am not so certain. 

 There are places where the lowest terrace may be of this nature ; 

 but this could not be proved, for beach gravel covers the face and 

 base. 



In any event, it may be concluded that the prevailing feature of 

 these ancient shore lines is the wave-bnilt, instead of the wave-cut 

 terrace. In this respect there is a marked difference in the features 

 of the present lake shore, and a resemblance to such coasts as the 

 sandy shores of New Jersey and the Carolinas. This is a feature 

 which needs to be explained and will be discussed in later pages. 



Irregularities of level of gravel ridges. — When formed by the 

 lake waters, these ridges were essentially horizontal. That is to say, 

 leaving out of question certain minor variations from place to place, 

 such as we see on any beach at present, the average crest of each 

 beach from one end of the region to the other, was a horizontal line, 

 just as is the case on the present lake shore. Still, at present, these 

 ridges are not horizontal. As determined by careful lines of levels, 

 and by numerous elevations obtained by other means, they are tilted 

 so that the eastern end is higher than the western. This necessarily 

 records a change in the level of the land since the beaches were de- 

 posited. Along the line of beaches from Cleveland to Silver Creek 

 the change amounts to over 90 feet. Therefore, since the dis- 

 tance is about 150 miles, the change in level amounts on the average 

 to about three-fifths of a foot per mile. The levels made in the 

 grape belt are not of decisive value for the distance between them 

 is not great. Still in the profiles (Fig. 69) one sees that very nearly 

 the same change is recorded.* 



* From Section 1 to Section 3 the distance is 3G miles. The crest of the 

 second beach is 185 feet above lake level at State Line, 195 feet at Port- 

 land and 221 foot just oast of Silver Crook. In other words, the beach 

 increases in elevation at the rate of about 1 foot a mile. There is little 

 doubt that the uplift is greater in the east than in the west. 



