221 



tinuous from the end <»(" Portuguese Lane south to the point, the 

 total exposed thickness being, probably, not less than 500 feet. 

 The slate is of a very uniform character, — gray, rather coarse, 

 very thinly and evenly bedded, well jointed, but without marked 

 cleavage. Some layers are finely pitted by weathering and 

 wave-action, indicating, possibly, some lime in the rock ; and 

 there are some indistinct concretions. But although the section 

 appears in every way favorable for the occurrence of fossils, I 

 have searched for them in vain. In the most northerly outcroj) 

 of the slate it is distinctly and repeatedly interstratified with 

 layers of hard, gray, and rather coarse sandstone, from two 

 inches to two feet thick. Since such intercalations of coarse 

 material are wholly wanting in the remaining 500 feet of the 

 slate, this outcrop is regarded as marking the transition from 

 the underlying conglomerate and sandstone (13) to the slate ; 

 and it is the chief fact relied upon in drawing the boundary on 

 the map. It is imnecessary to dwell upon its importance as 

 evidence that the slate conformably overlies the conglomerate 

 series. It may well be, however, tluit, as in the case of the 

 conglomerate in the Unit's Cove section, to I)e descril)ed in the 

 following pages, this intercalated coarse material is underlain 

 by a considerable thickness — 100 feet or more — of slate. 



It is impossible to carry the section farther south ; for the 

 cast and south shores of Beal's Cove are wholly composed of 

 modified drift which rises from 30 to 80 feet above the water, 

 and extends southeast across the Hockley district to the rail- 

 road, blottinij out everythinp^ but an occasional ledire of cfranite. 

 .Following the east shore of Weymouth Back River south 

 from Beal's Cove, no ledges of any kind are observed for 

 about 800 feet from the south angle of the cove, and then, 

 when nearly opposite the south side of Whale Island, we 

 reach the beginning of an outcrop of coarse granite which is 

 almost continuous along; the shore for 500 feet. The ijranite 

 is divided by three large east-west dikes ; but there is not a 

 trace of slate or any sedimentary rock. Between the nearest 



