172 ^Agricultural Geology of Onondaga County. [April, 



which had peopled those formations, not a vestige of them go up; 

 .tnd so far as succeeding deposits are concerned, their places are 

 as vacant as though they had never existed. This period passed 

 and that of the Onondaga limestone ushered in, and we are once 

 more introduced to new forms. If those of the water lime series 

 or of the magnesian rocks do not altogether cease, by far the 

 greater portion of them have passed away, and as before, the era 

 is a new one in the annals of life. The shelving beaches are 

 strewed with beings which the waters had never before cast up. 



To reach another era we have only to follow the layers of the 

 Onondaga limestone to that place where the black Marcellus 

 shales first appear. Not one of all the corals or of the molusca 

 pass beyond the limits of the limestone, and however strange it 

 may seem these shales are equally prolific in forms which are 

 confined to its own layers. It is not determined, however, whether 

 some of these may not go up into the Hamilton group; as a 

 whole they are limited to the walls of the shales, and the beings 

 which lived in the waters from which this group was deposited, 

 were not colonies going up from the shale. 



Let us retrace our steps and see how the matter stands in re- 

 view. 1. We begin with a blank in the organic world, in the 

 era of red and green marls. 2. New forms appear in the water 

 lime series, which constitute a second era. 3. The Onon- 

 daga limestone gives us a new platform, upon which life and 

 tenements are built. The fourth era is that of the Marcellus 

 shales, and lastly the Hamilton group is entitled to the place of 

 the fifth. We believe that some of the estates of Onondaga 

 county cover the five eras of ancient life. 



We are unable to give a satisfactory account of the waters of 

 Onondaga, though they rank among the most important in the 

 state. They belong, as a class, to the hard waters, excepting 

 those which originate in the most elevated parts of the county, 

 upon the hills which are capped with the silicious rocks. The 

 varieties of water are numerous. Among the most important are 

 the mineral springs, the well known salines, which, as they are 

 so well known, do not require a notice in this place. The wells 



