NARRAGANSETT PIER. 245 



considerable length, of darker and finer grain, showing the carbonaceous 

 character of the inclusion. Strike of the same, N. 16° E., dip 45° E. 



A third of a mile northwest of the Clump Rocks the pegmatite incloses 

 a small fragment of Carboniferous shaly sandstone. 



The eastern and much larger hill of Boston Neck shows frequent 

 pegmatite exposures on the eastern side toward the top, directly west of Bon- 

 net Point, and over a considerable area near its southern termination, south 

 of Watsons Pier. It is more probable, however, that this hill is composed 

 of pegmatite and Carboniferous rocks in frequent alternation than that it is 

 underlain by pegmatite alone. The more western hill contains numerous 

 exposures of granitic rock verging into pegmatite, near the Narrows, and 

 a few exposures of the same rocks on the western side. 



On Little Neck there are frequent exposures. They were not carefully 

 searched, but all the rocks examined were granitic, usually medium grained, 

 whitish or reddish, cut by pegmatite dikes or containing blotches of peg- 

 matite, the pegmatite being unusually coarse just west of the north end of 

 Beach Pond, where the mica plates are at times 6 inches broad. 



Between the two old wharves at Narragansett Pier, east of the Casino, 

 the Carboniferous rock is seen again, included as a very large block in the 

 granitic rock. It is chiefly sandstone, decidedly quartzitic, with white and 

 black mica, the latter more common along certain layers parallel to the 

 stratification. There is considerable crumpling in this rock, especially 

 toward the south end. The rock contains also. a layer of conglomerate. 

 The pebbles are so much drawn out and flattened along' the plane of schis- 

 tosity that they appear as indistinctly bordered whiter blotches on the general 

 rock surfaces; but transverse to the schistosity, especially along their shorter 

 diameter, their outline is often fairly distinct. They are usually one-fourth 

 of an inch thick, rarely more than a third of an inch, with a width of 1 to 

 1£ inches and a length of 3 to 4 inches. No one who had followed the 

 Carboniferous series in the order here indicated would fail to recognize the 

 Narragansett Pier exposure as belonging to this series. 



The granite at the pier is reddish and often pegmatitic. The exposures 

 were followed southward for 2 miles along the shore. It is undoubtedly 

 the same granite as that on Little Neck and Boston Neck. Since it includes 

 fragments of the Carboniferous series, as well as intersects the strata of this 

 series, it must be of more recent age. This subject is further discussed 



