674 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



farther east, but seems to continue across Wales Township, Erie County, to 

 the interlobate moraine in Sheldon Township, Wyoming County. 



The general width of this moraine is only about a mile and it is often 

 considerably narrower. Its narrowest portions are usually the best defined, 

 for the moraine is so weak that when spread over a width of more than a 

 mile it becomes difficult to map its limits. 



RANGE IN ALTITUDE. 



The portion of the Gowanda moraine Avest of Cattaraugus Creek has a 

 range of only about 100 feet in altitude, the lowest points being near the 

 level of the Belmore beach, 840 to 850 feet above tide, and the highest 

 about 950 feet. From Cattaraugus Creek northward past Lawton it 

 remains at similar low altitudes, but in crossing the ridge east of North Col- 

 lins it rises to about 1,300 feet. In each of the branches of Eighteenmile 

 Creek its altitude is not far from 1,000 feet, but on the ridge between it is 

 fully 1,300 feet. Farther east it fluctuates between about 1,100 feet in the 

 valleys and 1,500 feet or more on the ridges, and is fully 1,500 feet at its 

 iunction with the interlobate tract in Sheldon Township, Wyoming County. 



TOPOGRAPHY. 



This moraine throughout its course consists largely of small swells, 10 

 to 15 feet high, which are separated by sags and winding, poorly drained 

 depressions. Occasionally knolls 25 to 40 feet or more in height are found, 

 and on the whole the portions in valleys carry larger knolls than the por- 

 tions on ridges. Where the moraine is narrowed to about a half-mile the 

 knolls are usually very closely aggregated and the expression is strong; 

 but where it spreads out to a width of more than a mile the knolls become 

 more scattering and the expression correspondingly weak. In the portion 

 from South Wales eastward, as noted above, the knolls are very scattered 

 and it becomes difficult in places to determine the limits of the moraine. 



STRUCTURE OF THE DRIFT. 



In the portion of the moraine west of Cattaraugus Creek, and also 

 on the ridges farther east, the Gowanda moraine consists mainly of till. 

 Wells often pass from a yellow into a blue till at 8 or 10 feet. The till is 

 clayey in the low tract west from Cattaraugus Creek, but on the high tracts 



