318 LIMESTONE. 



Eange, Extent and Thickness. 



We will speak first of the dove-colored variety of the limestone portion of the group. 

 We take the following remarks concerning it, from Prof. Thompson's notes : 



"This rock was first observed [Jin Chittenden county], beginning at the south in 

 Charlotte, just east of the summit of the high ridge extending south from Globe Hill. Its 

 thickness here is only a few feet, and it is seen only a short distance north and south. It 

 next appears on the west side of Lonerock Point. Lying in the form of a wedge between 

 the red sandrock and black slate, rapidly increasing in thickness towards the north, attain- 

 ing to 20 or 30 feet before it becomes concealed at Eagle Bay. It appears again in Colches- 

 ter on the southeast side of Mallet's Head: also at Stave Point on the north side of the 

 outlet of Mallet's Bay, where there is a kiln for burning it into quicklime. In all these places 

 it lies under, and in contact with the red sandrock. From Milton through Georgia to 

 St. Albans Bay, it is abundantly developed at a short distance from the lake shore, being 

 most of the way several rods in width, at the surface of the ground. In Swanton it 

 appears again at several places; and at one locality, half a mile southeast from Swanton 

 Falls, it has been quarried for marble. The width of the exposure here of nearly naked 

 rock is about 25 rods, and it extends half a mile north and south, only very slight signs 

 of stratification are any where to be found in it. It is cracked and checked in various 

 directions, and there are some appearances of planes of deposit dipping East about 45. 



"This rock shows itself through most of the township of Highgate, and extends into 

 Canada." 



There is a large amount of this limestone in Highgate. There is no slate between it 

 and the Trenton limestone. It is from one to two miles in width, narrowing at the south 

 part of the town. North of Saxe's mill it appears in large, white bosses arising out of 

 the lowland. Near Church's house, nearly east from Franklin house, the limestone is 

 brecciated, and among the fragments the Trenton limestone is clearly discernible. At 

 Highgate Falls this limestone is interstratified with various kinds of slate, as is seen in 

 Fig. 256, and the great mass of it extends quite near to the Falls. East of Swanton Falls 

 it is very wide, and is of fine quality, insomuch that it has been sawed for marble, but 

 with poor success. Much of it is traversed by numerous small reticulated veins of calcite, 

 and it breaks into irregular angular fragments, like the limestone in Colchester. 



In passing south to the coarser limestones, we first find it northwest of Burlington, in 

 the vicinity of Lone Rock Point. We next saw it in Ferrisburgh, in occasional suddenly 

 expanding beds ; particularly east of Vergennes, and in sight of the village. It much 

 resembles serpentine at a distance. We crossed the range next northeast of Snake Mount- 

 ain, where the western border of the Red Rock, the east line of Addison and the carriage 

 road from Addison to New Haven, all meet at Otter Creek. At about the middle of the 

 highest part of Snake Mountain on the west side among the debris, this ugly rock takes 

 another start ; and we can trace it a great distance. It appears through the whole of the 

 east part of Bridport. A few obscure fossils, probably of the genus Euomphalus, appear 

 in it in the northwest part of the town. It is in a ledge of this rock, near Mr. Gale's 

 house, near the east line of Bridport, that metamorphosis first fairly takes hold. East of 

 it, as far as the quartz rock, nothing but white limestone is found ; west of this ledge 

 fossils occur abundantly in the unaltered Trenton limestone. 



