698 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



The main ridge leads from Royaltou eastward to West Shelby, but 

 becomes irregular, aud at West Shelby connects with a prominent morainic 

 spur which extends north about 2 miles It also changes in constitution 

 to a mixture of gravel and till. In the spur that leads north from West 

 Shelby there are sharp knolls 20 to 40 feet high, among which basins are 

 incloseci that cover areas of from 1 to 5 acres each. It is a very gravelly 

 belt, but there is usually a thin capping of till thickly set with bowlders 

 About a mile east from the north end of this morainic spur is an isolated 

 sharp ridge of sandy till, on which Ryan geodetic station was placed. 

 The ridge is about one-half mile long and trends north-northeast to south- 

 southwest. Its highest points are about 60 feet above the bordering 

 plain. There are knolls 15 to 30 feet high along its slopes. 



On the east side of Oak Orchard Creek there is greater complexity 

 than on the west. The main ridge is very definite all the way from the 

 creek to West Barre, but ridges north and south of it are scattered over 

 a neaidy plane tract occupying only a small part of the surface. The 

 main ridge in places presents a smooth surface like a beach line and is 

 narrow and low, the height being but 10 to 15 feet and width 50 to, 75 

 yards; but usually its surface is more irregular than a beach line, there 

 being variations of 15 to 20 feet in height within short distances. The 

 biilk is also greater on the whole than beaches commonly display, the 

 width being from an eighth to a fourth of a mile and the height from 10 to 

 40 feet. 



Of the scattering ridges found south of the main ridge the most 

 prominent is at Edwards geodetic station, its height being about 50 feet. 

 The majority are between 15 and 25 feet in height. These ridges are 

 commonly but an eighth of a mile or less in width and one-lialf mile to a 

 mile or more in length. The usual trend is from north of east to south of 

 west, being similar to that of the drumlins, but this is the onl}^ point of 

 resemblance, the surface being less regular than that of drumlins. They 

 also are largely composed of sand and gravel, while the drumlins are 

 mainly of till. 



North of the main ridge there are only scattering knolls and low wind- 

 ing ridges for a mile or two east from Oak Orchard Creek. A sharp range 

 of gravelly hills then sets in, which trends northwest to southeast. Its 

 highest points stand 75 to 100 feet above bordering plane tracts and its 



