VARIETIES. 523 



peculiar appearance. It is very finely grained, perfectly homogeneous, and very compact. 

 The divisional planes, supposed to be planes of stratification, closely resemble the divis- 

 ional planes of the quartz rock west of the Green Mountains for their regularity. Its color 

 is much lighter than that of the ordinary schists. There are also talco-micaceous and 

 epidotic talcose schists in Wolcott. 



The following is the order of rocks from Craftsbury to Johnson in this formation, be- 

 tween the clay slate and gneiss : Talcose schist with a few strata of quartz, novaculite 

 schist, talcose grit, novaculite schist, talcose schist, talcose schist with beds of quartz, 

 ferruginous quartz, hornblende schist, talcose schist, green clay -slate, ordinary clay slate, 

 talcose sandstone, talcose grit, gneissoid rock, talcose rock with silicious layers, gneissoid 

 talcose schist, limestone, calcareous sandrock, talcose schist with pebbles of quartz and 

 feldspar, talcose schist, argillo-talcose schist, a clay slate, talcose schist. In Johnson the 

 strata are full of the minor contortions already described, so much so as to render impos- 

 sible any judicious estimate of the strike and dip of the strata upon many ledges. 



The novaculite schists have changed into excellent novaculite of economical value in 

 Irasburgh. The same range extends to Coventry, and its relations to the adjacent rocks 

 are given in Fig. 268. In going west from the clay slates and upper Silurian limestone 

 of West Coventry village, the following is the order of the talcose rocks : Talcose schist, 

 talcose sandstone and conglomerates, light-green talcose mass with little stratification, 

 talcose schist, novaculite, talcose schist. 



In the north part of Coventry the remarkable bed of conglomerate, described previously 

 under the lithological characters of talcose schist, occurs, and is supposed to form a bed 

 in the formation, although it is within a quarter of a mile of the clay slate. Owing to 

 alluvial accumulations it has been impossible to trace this bed a great distance. 



There is very much of the novaculite in Newport. Some of the honestones from Lake 

 Memphremagog are well known for their excellent sharpening properties. Other varieties 

 of rock in Newport are granite, indurated talcose schist, and epidotic talcose schist. In 

 Troy the talcose rocks contain many small rounded pebbles. The remarkable deposits of 

 serpentine and associated minerals in Orleans County are described elsewhere. 



The widest portion of this middle range of talcose schist is between Hardwick and 

 Mansfield Mountain. It is narrowest in Marlboro, Dover, and Newfane. North of 

 Stockbridge it widens very suddenly. This rapid expansion may be connected with cer- 

 tain foldings of the strata, yet to be investigated. It seems to be connected with a range 

 of mountains running northwesterly in Pittsfield and Chittenden, at variance with the 

 common direction of the Green Mountain ranges. 



The gneiss of the Green Mountains, which has separated the middle and west ranges of 

 talcose schist south of Kichford, is marked upon the map as terminating in Richford. 

 Hence the two ranges unite, and turn sharply around the gneiss. Jay Peak is coarse 

 talcose schist, according to Prof. Adams, the talc being in rather large proportion, with 

 numerous small, irregular masses of pure chlorite, and an irregular vein of white quartz. 

 The rock is often highly charged with crystals of magnetic iron ore, so as powerfully to 

 affect the compass. 



The western range of talcose schist commences at the south line of Lincoln. It is there 

 very narrow. In Lincoln the rocks are talcose schists and sandstones. In Huntington 



