258 GEOLOGY OF THE THIRD DISTRICT. 



ore, that of Verona being preferred. The discovery of gypsum, in the purest state in which 

 this substance is known to exist in large masses, may prove of importance, and lead also to 

 the discovery of other localities in the same position. The gypsum occurs in the upper layers 

 of the grey sandstone, the second deposit of the east end of the Onondaga salt group cover- 

 ing the sandstone ; and the adit by which the gypsum was obtained, is in part excavated in this 

 mass. Throughout the county, the group is readily recqgnized in all the water courses south 

 of the river, after passing the conglomerate ; being between that rock and the red shale, 

 which latter extends from the west to Crugar's, formerly Tisdale's saw-mill. From an un- 

 known point to the east of the saw-mill, and west of the creek at Wicks' store, the red shale 

 ends, and the next deposit of the Onondaga salt group takes its place, and extends east to 

 near the Hudson. 



The Onondaga salt group ranges parallel with the lower group and rocks through the 

 coimty. Its lower mass, the red shale, terminates to the east of Crugar's saw-mill, although 

 its thickness cannot be less at the mill than forty or fifty feet. The mass above, and which 

 succeeds to it, consists of yellowish and drab layers by exposure, usually thin, some more or 

 less earthy, and others solid. They, with the overlying Water-lime group, and other calca- 

 reous masses, have given rise to several deposits of tufa, which skirt the Clinton group in 

 part. The first mass of tufa to the east, ccvers the hill-side east and west of C rill's : it is 

 colored yellow by hydrate of iron. The nexi deposit is more considerable ; it is in greatest 

 amount near Mr. Field's distillery, and extends up to near the top of the hill. It is earthy 

 and solid, some of which is in the state of alabaster, but the latter is in no great quantity; 

 this deposit extends along the road by the side of the creek, for a mile and more. The third 

 deposit of note is in Myers' creek, on the line of the red shale and the Clinton group ; the 

 lower part shows thin solid layers, very tough, and is burnt for lime and carried to Utica, 

 making a very white lime ; the part above, is the usual irregular deposit. There are other 

 depositions along the range, but of small amouit. 



South of this group is the Water-lime group, whose range is readily traced from the hill 

 to the south of Crill's ; south of Mr. Crugar's kouse ; Cedarville village ; and the hill side on 

 the farm of Edward S. Brown in Litchfield. This group furnishes good building stone for 

 common purposes, and good lime ; and though no water-lime is made in the county, if a de- 

 mand existed, there is no reason why it should not ke made. 



The Pentamerus limestone, the Catskill shaly limestone, the Cauda-galli grit, the Onon- 

 daga limestone, and the Comiferous limestone, extsnd through the county ; their surface in 

 many places is covered with high east and west ridges of alluvion, particularly through the 

 towns of Warren and Columbia. All information CDllected of these rocks were given imder 

 their respective heads. 



The Marcellus shales underlie the soil of alluvion in the south part of the towns of Warren, 

 Columbia, and the greater part of all Winfield. In Columbia, it is frequently met with upon 

 the surface. 



