54 



the Mount Bethel Church, pursuing the same Hne of elevation, 

 namely, that immediately west of Musconetcong Valley, we trace 

 the same anticlinal line, or more probably, one parallel and nearly 

 continuous with it, through what is termed the Mansfield Valley. 

 This is properly the axis of the upheaved belt of gneiss which lies 

 between the Musconetcong and Pohatcong streams. We have 

 proofs that the elevatory force extended southwestward, nearly 

 to the Delaware, inclining the beds of limestone, on the one hand, 

 towards the Musconetcong ; and on the other, towards the Po- 

 hatcong. 



That this axis of elevation is not strictly coincident with that 

 which comes in to meet it from the northeast, is rendered likely 

 by the variable undulating dip of the rocks along the centre of 

 the Mansfield Valley, where these axes should pass. It is a phe- 

 nomenon which the geologist may often have occasion to remark 

 when detecting the near juxtaposition of two anticlinal axes 

 which overlap or pass each other, that the strata immediately 

 within its range are almost invariably thrown in a succession of 

 opposite or undulating dips. 



To the southeast of the general axis of elevation, viewing it as 

 one, thus traceable from near Lockwood to the Delaware, we 

 have the singularly uniform straight and narrow synclinal valley 

 of the Musconetcong, along nearly the whole length of which 

 the limestone will be found dipping away from the hills which 

 bound it towards a synclinal axis, which ranges not exactly along 

 its centre, however, but lies nearest to its southeastern margin, 

 approaching the stream itself. This departure from a central po- 

 sition in the synclinal axis of the valley, is a very usual feature in 

 the axes of the Appalachian chain. It results as a necessary con- 

 sequence from the northwestern dips belonging to the anticlinal 

 axes lying next to the southeast, or that of the Schooley's Moun- 

 tain chain, being steeper than the southeastern dips from the axis 

 of elevation northwest of it. This want of symmetry in the dip 

 of the strata would not claim a special mention in this place, but 

 for the truly remarkable circumstance, that throughout nearly the 

 whole length of the Appalachian chain, embracing many hundred 

 anticlinal axes, the same rule prevails with scarcely an exception, 

 the northwestern dips being steeper than the opposite south- 

 eastern ones. 



