OF THE APPALACHIAN CHAIN. ^ 529 



composed of the lower part of this series ; for, stUl further south, 

 the dip is reversed to the south-southeast, and in a traverse from 

 Seigen to the Taunus, across the strike, (a distance of about fifty- 

 miles,) the same dip is continued, with very few interruptions. 

 Considering their high inclination, this fact seems to give an 

 almost incredible thickness to the deposits in question. But the 

 vertical sections do not give the order of superposition, for at 

 Dillenburg, and on the Lahn, two great Devonian troughs are 

 brought in among the older strata, without any general change of 

 dip ; and if we accepted the vertical sections as the sole proofs of 

 superposition, we must place the Devonian, and a part of the car- 

 boniferous series, under the chain of the Taunus." 



If we are correct in our interpretation of the phenomena here 

 described, they present an instance of sli-ucture which is of fre- 

 quent occurrence in the Appalachian beh, where the rocks of the 

 southeastern portion of a synclinal flexure, are folded over into 

 southeastern or inverted dips, or where the axis-planes of both anti- 

 clinal and synclinal flexures are inclined very obliquely to the 

 horizon, dipping in parallel directions to the southeast. The chain 

 of the Hundsruck, and its continuation, the Taunus, of which they 

 regard the Quartzite and Chlorite slates as " but altered forms of 

 a great Silurian group, under the Eifel limestone," would thus ap- 

 pear to occupy a similar position to that of some of the ridges on 

 the southeastern margin of the Appalachian region, where we meet 

 with very similar phenomena of alteration, accompanied by a 

 large amount of intrusive matter, and adjacent to this, on the 

 northwest, many inversions and foldings of the strata. Including, 

 in one view, the portions of Belgium, the Rhenish provinces, the 

 Westphalian coal-field, and the Hundsruck, Taunus, and Hartz 

 ranges, described by those geologists as displaying an extended 

 series of Cambrian, Silurian, and Devonian strata, we are strongly 

 of opinion, that the relations of dip which they present, will be 

 found reducible, in great part, to the laws of structure we have 

 endeavored to develope, and fairly referable to a similar undula- 

 tory movement directed towards the northwest. 



From the observations of Dr. Fitton, on the structure of the 

 Wealden and associated formations, as detailed in his admirable 



