DOLOMITE. 387 



gray color, having shining, wavy surfaces, which are covered with an argillaceous film. 

 They split into good flagging stones. Other beds upon Aldis Hill are intermediate 

 between sandstone and hyaline quartz. 



The brecciated rock of this group is also in St. Albans. It may be seen in the south 

 part of the village, and is of a dull gray color, composed of fragments of quartz rock of 

 the same color. 



The quartz rock is more abundant. There are beds of it in the extreme west part of 

 Huntington. Probably such beds are common between Hinesburgh and Westford. The 

 blunt spur, extending from Fairfax to Milton Falls, is mostly quartz rock. In passing 

 from Georgia depot to Fairfax Center, there are alternations of quartz rock and conglom- 

 erate. The number of these beds, and their relation to each other, need investigation. 

 At a saw mill, a short distance east of Georgia depot, the quartz rock is very finely 

 developed. From La Moille River to the east part of St. Albans, the quartz rock may be 

 traced continuously, in quite a wide belt. In St. Albans it occurs upon the high hill east 

 of Aldis Hill. It is of a dun color here, and is thickly traA r ersed by segregated veins of 

 white quartz. A section from the Georgia slate at its southern extremity, in St. Albans, 

 to North Fairfax, passes over the following rocks in an ascending order : Georgia slate, 

 silicious limestone, quartz rock, talcose schist, coarse talcose conglomerate and talcose 

 schist. These are. all members (except the first) of the group of rocks now described. 

 There are other beds of quartz rock in Fairfield and Sheldon. 



The calcareous rocks are not numerous. They are mostly limestones ; but occasionally 

 the talcose schist is calcareous. The latter variety are found in Richmond and Jericho. 

 The limerocks are found in Milton, at the corners of the four towns of Georgia, St. Albans, 

 Fairfax and Fairfield. In Fairfield, No. 3 V G ; Sheldon Four-corners, No. /,| ; and in the 

 west part of Franklin, Nos. jVs to ^ 9 . The limestones in Franklin are quite abundant, 

 and are of good quality. An analysis of one of them gives the following results : 



Silica, or insoluble silicates, 30,419 



Peroxyd of iron and alumina, 2,331 



Carbonate of lime, . . 35,419 



Carbonate of magnesia, . 31,831 



100,000 



This proves to be a dolomite. Its locality is about a mile west of the village of Frank- 

 lin. The rock has been burned for lime. There is not a distinct bed of dolomite, but 

 rather a series of small beds interstratified with talcose schist. There is a similar calcif- 

 erous rock near Judge Hubbard's house, a mile north of the village. Dolomite is still 

 more abundant north of Judge Hubbard's near the Canada line. The rock here is prop- 

 erly the Winooski limestone. 



The novaculite schist is the most common in the north part of the deposit. Upon 

 Section XI, it is found at Fairfax, Fairfield, Westford, and Milton. See Nos. 2 y r , a l 3 l a , 

 to 830, aVz) aVr? an< l sVs- It occurs, also, at Sheldon Four Corners, ^Q, and is very 

 abundant in Franklin. See Nos. ^ to i&. It is one of the most common rocks in 

 Franklin. 



The talcose schist is the most common rock in the belt colored as talcose conglomerates, 

 insomuch that we have sometimes questioned the propriety of separating this belt strati- 



