432 BIRD MOUNTAIN. 



range is found in the west part of Danby running nearly north and south. It is tho 

 direct continuation of a range of mountains in Sandgate, viz., Swearing Hill, Minister 

 Hill, Seymour Peak, and Bear Mountain, and composed of the same schists, though not 

 quite as high. The same rocks occupy much of the area of the State, west of Danby. 



Numerous details of these rocks in Tinmouth and Middletown are given upon Section 

 V. The range of mountains before mentioned, passes through Danby, Tinmouth, West 

 Clarendon, Ira, Rutland, Pittsford and Sudbury, where it degenerates into a hill, termin- 

 ating finally in Cornwall. Its eastern limit lies along the west line of Clarendon, and 

 then turns northwesterly, through a district recently ceded to Ira, and, by a small neck 

 on the Rutland and Clarendon line, joins an otherwise isolated deposit of schist running 

 lengthwise through Rutland into the towns north and south, each a short distance. The 

 length of this small range is eight miles, and it is usually less than a mile wide. It is a 

 sort of talco-argillaceous schist, and may be seen to good advantage upon the hill east of 

 the marble quarries in West Rutland, especially where the road to Rutland has crossed it. 

 It appears in numerous ledges south of the latter locality, and in Clarendon less than a 

 mile southeasterly from the springs. The hill may be easily traced into Pittsford 

 northerly the rock having essentially the same character throughout. A small portion 

 of the same kind of rock is associated with the quartz rock on the east side of Otter 

 Creek, near Mr. Grigg's house. 



Bird Mountain in Ira is an interesting locality. The summit is composed of a conglom- 

 erate of blue hyaline quartz in a talcose base, the pebbles seldom exceeding a kernel of 

 corn in size. Some metamorphic action has very greatly obscured the dip of the rocks 

 upon the summit. There are planes, probably of cleavage, dipping 57 W., and indica- 

 tions of strata dipping to the west a few degrees. A mile south of the summit, the notes 

 of one observer (Mr. Hager) state that the conglomerate is interstratified with a slate that 

 dips 45 E. It is certain that in the valley east of Bird Mountain (the range runs north 

 and south), the slate dips to the east. Hence it is most likely that this conglomerate is 

 interstratified with the slates. Further south it is said to occur, though not abundantly. 

 It has not been found north, but the line of its strata passes through an unexplored 



region. 



Herrick Mountain, in Ira, is composed of a talco-argillaceous schist very much contorted. 

 It is in the same range with Bird Mountain. 



There are beds of limestone in Ira that are quite interesting. Upon the land of Joseph 

 Tower, three miles southwest of West Rutland, on the eastern declivity of a hill is a bed of 

 fossiliferous limestone. There seems to be some local change in its position, for in com- 

 pany with an overlying slate it dips to the west, while both dip east forty rods north on 

 the line of strike. Upon Ira Mann's land there is a bed of limestone twenty-five feet 

 thick, without fossils. Fossils were also found near the middle of the town, and on the 

 south line of Ira next to Middletown. West of Middletown Center there were also indica- 

 tions of a considerable amount of limestone in the slate. The town is in general made 

 up of green and black clay slate more or less contorted. In most of the territory occupied 

 by the talcose and talcoid schists there is little of interest. 



There is a curious gap excavated through the range of mountains composed of the tal- 

 coid schist, in Ira. Its bottom is lower than the level country towards Rutland, so that 



