GEOLOGY OF THE CONNECTICUT VALLEY DISTRICT. 289 



glomerate lie in the centre of the field, and are therefore the newer 

 members of the series. 



I have not traversed the country between this mine and the road run- 

 ning north-east from Parker hill. The examination of the adjacent terri- 

 tory, however, indicates the character and position of the strata here. 

 We have, first, the argillitic Lyman schists, with south-easterly dip; then 

 a conglomerate composed of fragments of the same rock; and, lastly, 

 green-colored schists dipping 85° N. 40° W., indicating the presence of 

 an anticlinal axis before reaching the Parker Hill road and the repetition 

 of the clay slates. 



This new slate range begins at Parker hill, and widens northerly, being 

 half a mile wide on the section line, and nearly two miles by the north 

 town line. This slate is usually inclined very steeply in a south-easterly 

 direction. 



Passing on to the hill between this slate range and that next farther 

 west, we find a development of the Lisbon group between them. The 

 slate extends about a quarter of a mile w^est of the road at L, B. Hos- 

 kins's. The schists are considerably slaty, and there are narrow beds 

 of jasper intercalated with them. Certain cupreous veins cut across dol- 

 omitic strata, dipping 60° a little east of south. This set of cupreous 

 veins is probably continuous from the beds west of the Grafton mine, 

 represented upon Fig. 30. There must be an anticlinal in this area west 

 of Hoskins's, because the slates make their appearance, with the usual 

 high south-easterly dip, at the east base of Gardner mountain. The axis 

 may be an inverted one ; but we have no direct evidence from observa- 

 tion along this line. The clay slates occur, with the dip of about 60° S. 

 E., along the carriage-road at the east foot of the mountain. This may 

 be two hundred or three hundred feet thick, but sufficiently abundant to 

 indicate the presence of a newer rock, and consequently of a synclinal 

 fold in the strata. At the Oro mine the position of the strata is essen- 

 tially the same with that of the slates just mentioned. East of it there 

 is a band of quartzite ; and three hundred and seventy-five feet further 

 up the mountain is a band of dolomite. Much of the rock on the east 

 side of the mountain, near the copper belt, is soft and light-colored, and 

 therefore suggestive of the Lyman group. 



Fig. 32 shows the position of the Huronian rocks, without so many of 



VOL, II. ij 



