STEDCTUEB OF THE BASIK 



123 



strata, of which there can not be less than 12,000 feet now remaining. 

 East of this Hne the upper strata are apparently denuded and the structure 



y/'^o' 



'7/VS* 



-Jl^O' 





^S'Oii 



JfPfS 



4i'^ 



i?2«00' 



-^/•.*^ 



^/'aa 



' 7/ W* 



Fig 9 —Outline map and general cross section of the basin 



is less well shown (see fig. 8)^ largely owing to the coveiing of glacial 

 drift. In the southern arm, as is shown in Dr. Foerste's report, like 





Kg 10 —Edward Hitchcock's cross section, of the Carbomferou«j area (1841) 



changes have taken place, and the incursion of the sea has done that which 

 is performed by sheets of sand and gravel in other parts of the basin. 



