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constantly to the west, varying from 45° to 60° or more 

 as we approach the conglomerate, the actual exposed thick- 

 ness of the slate being, probably, about 900 feet. In one 

 ledge only on the northeast shore of the cove, a few scatter- 

 ing pebbles have been observed in the slate. It resembles 

 the lower slate in the fine and perfect jointing, which is 

 particularly well developed on the point, yielding prismatic 

 blocks which are sometimes remarkably slender, less than a 

 square inch in section, and several feet in length — monolithic 

 columns in miniature. For the most part, at least, it is of a 

 darker gray color than the lower slate, and somewhat darker, 

 also, than the slate of the Beal's Cove section. In following 

 the slate north from Huit's Cove, the strike seems to change 

 gradually with the conglomerate, and the dip becomes more 

 variable ; but on crossing the fault terminating the conglom- 

 erate the strike changes abruptly to N. 65°-70° E., and holds 

 that general direction across the north end of the melaphyr ; 

 while the dip between the melaphyr and the north shore is 

 extremely inconstant. This mass of slate is, in fact, highly 

 contorted, being contrasted in that respect with all the other 

 outcrops of Hingham. The slate shows no special alteration 

 in tlie vicinity of either the melaphyr or the great masses of 

 diabase which break through it. In general it is a soft, thin- 

 bedded, dark gray slate, showing in some of the ledges a good 

 lamination cleavage ; althougli the true slaty cleavage, which 

 holds a nearly constant attitude throughout this district, is 

 usually transverse to the bedding. In spite of the fact that 

 tlie dip of the slate is extremely variable, it is easily seen that, 

 as the map shows, the prevailing or true dip is north near the 

 melaphyr and south near the shore, indicating an irregular 

 synclinal fold east of the transverse fault, the axis of which 

 is roughly marked by the great dike. It does not appear, 

 however, that the dike has materially influenced the character 

 of the folding. The contortions are, of course, a normal 

 feature of an open syncline ; but whether either the fold or 



