GEOLOGY OF THE CONNECTICUT VALLEY DISTRICT. 353 



tinues into Corey hill, is cut deeply by the valley of Mink brook, but 

 rises into large hills in the north part of Lebanon. These are again cut 

 by the Mascomy river; and the country rises into considerable eminences, 

 but falls off before terminating in the south part of the town. As rocks, 

 we have, first, the typical variety of protogene ; second, common gneiss, 

 or that which contains a considerable black mica ; third, schists, consid- 

 erably ferruginous, passing into mica schists ; fourth, quartz beds ; fifth, 

 hornblende schist, at the borders, which may belong to the Huronian 

 system. The most northern of the hills referred to this series is deeply 

 covered by drift, with a strongly ferruginous soil. Next, the Spencer 

 hill has ledges of gritty pyritiferous mica schist. About L. Hall's the 

 rock is similar, dipping as much as 55° N. W. South of O. Pinneo's we 

 have a mixture of ferruginous, micaceous, and gneissic strata, dipping 

 45°-50° N. 32° W. With them is a quartz bed ten or twelve feet wide, 

 extending for several rods. About on the top of Prospect hill the rocks 

 are similar, dipping 20° N. 26° E. They are the same on the summit. 

 North of Lord's hill, where a road turns to O. Pinneo's and to the south, 

 are ledges of micaceous and ferruginous rocks dipping 50° N. At J. C. 

 Child's the same schists, less siliceous, dip 50° N. W. At H. S. Davis's 

 there is gneiss dipping 65° N. 32° W. Lord's hill is composed appar- 

 ently of the same materials with Prospect. Perhaps the schists as far 

 south as the bases of Prospect and Lord's hills should not be ranked 

 with the Bethlehem. I put them here provisionally, chiefly to render 

 unnecessary the making of another division of the strata. 



The unequivocal strata show themselves to the south of these high 

 hills. At A. Wright's the gneiss dips N. 13° E.; at J. J. Mason's the 

 dip is 25° N. 2° W., with a band of white quartz twelve or fifteen feet 

 wide, and like that mentioned on the north side of Prospect hill. The 

 ledges on the south side of the last-named hill are numerous, dipping 20° 

 northerly. It is 18° N. 12° W. at T. W. Durkee's. By C. C. Foster's 

 the dip of gneiss is 30° north-westerly. The gneiss may be followed a 

 short distance down the ravine towards C. Houston's till it adjoins horn- 

 blende schist, dipping in the same general direction. Near W. Hall's, on 

 top of Balch hill, is a gneiss dipping 20° N. ^,7° W. The rock contains 

 a large part of black mica, and this seems to characterize all the layers 

 on the west side of the area, others occurring in Lebanon. The same is 

 VOL. II. 45 



