114 GEOLOGY OF THE THmD DISTRICT. 



at the falls of Perryville, and also that of Cazenoyia falls on Chittenango creek, showing a 

 thickness of over one hundred feet. 



It faces the hill to the south of Chittenango village, on the road to Cazenovia, and is there 

 quarried and burnt for water-lime. At the quarry where the upper layers are exposed, the 

 lowest one is drab or light grey, mottled with blue, divided into two courses, and again sub- 

 divided, but not regularly : four feet thick. This is burnt for water lime. 

 Above : Blue layer, striped ; showing courses by exposure and fracture ; surface often 



notched ; the sides and elevations showing a fibrous structure, and coated with a black 



or brownish glazing : four feet. 

 The 3d layer is also burnt for water lime ; it is of a light drab, in thin irregular courses or 



other divisions, the effect of weathering from an original cause : over tluree feet. 

 4th. Irregularly divided by oblique cracks, usually in three directions ; the outside makes 



good Umc, but there is too often a hard core which renders it useless for burning : five 



feet thick. 

 5th. This layer is in very thin courses, with short curved surfaces, a structure very common 



to much of the limestone through Oneida, that of Oriskany falls being a remarkable 



example. This layer terminates the group at this place. 



24. 



The preceding wood-cut is a representation of two thin layers observed at this quarry, 

 making a part of one of the large layers of water-lime. They were not much over an inch 

 thick, and evidently had hardened or set before the enveloping part had assumed the same 

 state. A reference was made to this fact in the Report of 1839, when explaining the cause of 

 the arching observed above some of the masses of gypsum, and its absence in others. The 

 arching existed where the part over the gypsum was solid ; if otherwise, there was none, 

 showing that the fixation or consoUdation of the arched part took place before the accretion of 

 the gypseous particles, the expanding of which raised the solid or hardened part ; and where 

 this did not exist, the parts above must have subsided to where there was less pressure. 



The next point of interest is in Onondaga county, near Manlius square, at about three- 

 fourths of a mile to the southwest of the village. It shows the same masses as at Chittenango, 

 but differs a little in quality : the lower layer contains a larger proportion of ordinary lime- 

 stone, free from all accretions of a siliceous nature, and therefore makes a first quality of lime. 



It forms the well known falls of Manlius, whose height appeared to be about forty feet. 



At Brown's saw-mill, rather more than a mile to the south of the village, there is the greatest 

 exposition of one of the layers of drab or water-limestone proper, which eidsts in the district, 



