RHODE ISLAXD COAL MEASURES. 201 



South of Middleboro, on the west bank of the Namasket River, are 

 three low outcrops of gritty slate with thin layers of white quartz pebbles, 

 the size of the pebbles being not over an inch in diameter. Beds of this 

 character are probably not far above the base. It is interesting to note 

 again in connection with these beds the outcrop of granitite which occurs 

 immediately north in Namasket village. 



At the southwestern border of Great Cedar Swamp, although there 

 are no outcrops, the abundance of slabby sandstones in the fences indicates 

 the probable eastward extension of the sandstones which occur near the 

 middle of the Coal Measures in the western part of the basin. 



The area of felsites in Plympton has already been described (see 

 p. 116). 



