GEOLOGY OF TKE CONNECTICUT VALLEY DISTRICT. 2// 



and the Wing road the position is 80° N. 42° W. Oak hill shows the 

 dip of 40° N. 42° W. The inclination is like this a quarter of a mile 

 north of the Littleton cemetery, at E. P. Miner's. I think the dip is 

 higher at the most northern development of the gneiss, on Mann's hill. 

 Common gneiss and hornblende schists are interstratified there. Two 

 of the sections soon to be presented show this gneiss in its relations to 

 the chloritic strata, it being ajDparently beneath them unconformably. 



3. HUKONIAN. 



This formation exists in this field in three parts, — the Lisbon and 

 Lyman groups, and the auriferous conglomerate. The two first are sep- 

 arated upon Fig. 27, and were described for the first time, under these 

 appellations, in the article cited above. The first is the lower division, 

 embracing the greenish schists, conglomerates, copper-bearing strata, 

 quartzites, jaspers, and dolomites, usually referred to this age and re- 

 garded as characteristic of the group. This rock is disposed in a syn- 

 clinal way, dipping north-westerly where it is nearest the Atlantic gneiss, 

 upon the east side of the basin, and south-easterly upon the west side, or 

 on Gardner mountain. The upper series is inclosed within the limits 

 of the Lisbon group, and consists of drab schists, mostly of silica, with 

 small percentages of iron, lime, and magnesia, and weathering very light, 

 so that in the field we called them "white schists." Many ledges are 

 conglomeratic, the pebbles being mostly elongated, and composed of es- 

 sentially the same material with the mass of the formation. Dolomite is 

 especially abundant in it. The uppermost member is a conglomerate of 

 siliceous pebbles, never exceeding two hundred feet in thickness. It is 

 called auriferous, because assays of it in several places indicate the pres- 

 ence of a small amount of gold. Irregularities of direction and faults 

 are beautifully illustrated by the areas occupied by this member, as will 

 be particularly described. Though somewhat thrown out of place, the 

 general arrangement of the Lyman group and the conglomerate is that 

 of subordination to the Lisbon series, or a synclinal arrangement within 

 the limits of the latter. 



In order to illustrate the relations of the three members of the Huro- 

 nian system to each other, and to the underlying and upper strata, I will 

 insert a section showing the outcrops between Bronson's lime quarry, in 



