OF THE APPALACHIAN CHAIN. 483 



to the Geological Association, speaking of the remarkable appar- 

 ent inversion of the dip, along the western side of New England, 

 and through the Appalachian chain, no longer ascribes the phe- 

 nomena simply to a toss over of the strata, but to a succession of 

 folded axes, causing a high or more frequently an inverted dip on 

 the western side. In another part he states, that although he does 

 " not fully adopt, he cannot but look with a favorable bias upon 

 this solution of the problem." In explanation of the manner in 

 which the strata acquired this folded structure, he supposes that 

 while yet in a plastic state, and but slightly elevated, they were 

 acted upon by a force exerted in opposite du'ections, from near 

 the Hudson and Connecticut rivers ; and observes, that this force, 

 " if powerful enough, might cause them to be folded up into sev- 

 eral ridges, and if more powerfvd along the western than the 

 eastern side, they might fall over so as to take an inverted dip, 

 mthout producing any remarkable dislocation." 



In the second edition of his Elementary Geology, published 

 in August, 1841, Prof. Hitchcock, in discussing the phenomena, 

 refers again to the theory of two forces acting in opposite direc- 

 tions at the tAVO extremities of the strata, and suggests in addition 

 the elevating action of gaseous or melted matter beneath, omitting, 

 however, to account for the general southeasterly direction of 

 the dip. 



As the priority of our views in respect to the fact of an inverted 

 and folded structure throughout the chain from Virginia to west- 

 ern Massachusetts, is, we think, clearly established, by our several 

 publications above cited, we can only ascribe the omission, on 

 the part of om* esteemed friend, Prof. Hitchcock, distinctly to re- 

 cognize it, to the insulated manner in which our descriptions and 

 general views have appeared in ovir Annual Reports and other 

 occasional publications. 



Of the Flexures of the Strata, and the Law of their 

 Gradation, from Southeast to Northwest. 



The above-described phenomena of the dips in the Appalach- 

 ian range may, we think, be readily accounted for by the peculiar 



