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marked as partly sandstone is also all melaphyr ; so that there 

 is no evidence, as once supposed, of sandstone overlying- the 

 melaphyr. (2) Directly north of these ledges, about half 

 vv^ay between there and the shore, in the area colored as slate, 

 is a ledge w^hich appears on the map as sandstone and slate ; 

 but I am now satisfied that it is really fine-grained granite and 

 felsite overlain by compact, slaty, and chloritic melaphyr. 

 The boundary of the inelapliyr at this point should thus be 

 carried a hundred feet farther north as well as east. But the 

 special significance of this outcrop seems to be that it shows iis 

 the actual base of the melaphyr, and that the northeast corner 

 of this great block of melaphyr is tilted up a little higher, at 

 least, than any other part. 



That tlie contacts between the melaphyr and the sedimentary 

 rocks bounding it on the west and north are lines of profound 

 displacement is unquestionable, unless we are prepared to regard 

 the melaphyr as intrusive in the slate and conglomerate, that 

 is, as forming a vast dike or laccolite ; a view which, it may 

 be stated once more, finds no support whatever in the 

 petrogra[)hic characters of the melaphyr, nor in any facts now 

 exposed to our observation. The slate forming the shores of 

 Unit's Cove and extending around the northern end of the 

 melaphyr is undoubtedly, as previously explained, the great 

 slate (14)of the Beal's Cove section, and in its normal position, 

 or stratigraphically, it must be separated from the melaphyr by 

 more than a thousand feet in thickness of the conglomerate 

 series ; yet here it lies directly against the melaphyr or separated 

 from it only by the single bed of conglomerate, which, as the 

 detailed observations will show, is clearly the highest member 

 of the conglomerate series. We thus see that, simply as a 

 measure of erosion, the melaphyr is impressive, since there 

 must have been removed from its surface, not only the entire 

 couijlomerate series of Hinoiiam, but also the still sfreater volume 

 of the overlying slate scries ; and the l)ordering displacements, 

 although thev have barclv sufficed to brino- the bottom of the 



