182 GLACIAL GRAVELS OF MAINE. 



The series beg-ins near the south line of Norridgewock as a number of 

 ridges separated by intervals varying up to near 1 mile. The series extends 

 southwestward along a low pass to Smithfield Village, where it expands into 

 a plain more than 50 feet high. On the north the plain is continuous for 

 about one-fourth of a mile from east to west, and it sends out three parallel 

 tongues south for one-third of a mile. The material is coarse gravel and 

 cobbles at the north side of the plain, but becomes rapidly finer toward the 

 soixth, passing into fine sand, and this into sedimentary clay. A continuous 

 plain of sedimentary clay extends from Norridgewock along the line of this 

 gravel series, and thence all the way to Augusta. The surface of this clay 

 is strewn with numbers of stones and angular bowlders 2 to 12 feet in 

 diameter, but not with anything resembling a sheet of till; hence I refer 

 the erratic bowlders to floating ice. The bowlders may have been deposited 

 either in a broadened osar channel, in which case this is a plain of osar 

 border clay, or in an arm of the sea, or in an overflow channel of the great 

 Sandy River (Kennebec estuary of that time). The graA^el plain at Smith- 

 field Village is a delta-plain of some sort, and it is situated at about 350 

 feet elevation by aneroid. This makes it probable that the glacial stream 

 here flowed into a glacial lake, or, what is equivalent, a broadened osar 

 channel. For several miles soiith of this point the clays bordering this 

 gravel series have an elevation of more than 250 feet. 



South of Smithfield Village there is apparently no gravel for about 2 

 miles, and then a series of gravel ridges crosses the northeastern arm of 

 Belgrade Great Pond. It appears for about a mile on the east shore of the 

 pond, and at Horse Point runs southward into the Avater as a long gentle 

 sloping cape. It reappears on the south side of the pond, and soon takes 

 the form of a series of reticulated ridges inclosing kettleholes and lake- 

 lets. About a mile north of Belgrade station of the Maine Central Rail- 

 road a rather level plain extends for one-fourth of a mile or more to the east 

 of the main ridge. It was thrown out from the west around the south end 

 of the high hill known as Belgrade Ridge. It consists of rather horizontally 

 stratified fine gravel and sand, with a few layers of clay, and is plainly a 

 small delta. To the east of this deposit lies the valley of Messalonskee (Snows) 

 Pond, in Belgrade and Sidney. The plain in question is from 40 to 60 feet 

 above the pond, which is 240 feet above the sea. East and northeast of the 

 delta-plain just described no sedimentary clay appears on the northwest side 



