244 



Report of the State Geologist. 



and rocky for most of the distance to Jamesville, thft average descent being 

 about fifty feet per mile. North »f Jamesville, where it breaks through the 

 limestone beds, it becomes a narrow gorge, with a cascade at Dunlop's mills, 

 w here the first saw mill in the county was built, in 1792, and the first grist 

 mill, in 1793, by Asa Danforth. Half a mile north of Dunlop's mills the 

 ''Jamesville cut,' 1 a canyon fifty rods wide, 250 feet deep, and three miles 

 long, diverges towards the w est and connects Butternut creek \ alley w ith the 

 Onondaga valley. The Delaware, Lackawanna and Western railroad runs 

 through this cut and the entire length of the Butternut creek valley south 

 of Jamesville. 



The Onondaga valley is t he north end of an ancient river bed that, at the 

 close of the glacial epoch, had been tilled with drift to so great a height in 

 w hat is now the township of Tully, that a col w as formed at an elevation of 

 1,200 feet A. T., the w ater on the south side following the old channel to ihe 

 Susquehanna river, and on the north to Onondaga lake and the Seneca river. 

 At the point where the southern boundary line of Onondaga county crosses, 

 the valley is about three miles w ide, the southern extension of Butternut 

 creek valley coming into it just there from the east and nearly doubling the 

 w idth. The sides are 300 to 500 feet high and very precipitous. The col, 

 or separating ridge, lies on the north side of all the Tully lakes, except Crooked 

 lake. Two and one-half miles north of the county line, the high upper section 

 ends abruptly, and the floor of the valley sinks, in the distance of about half 

 a mile, from 1,200 feet A. T. to 800 feet A. T. At the foot of this declivity 

 a well sunk near the middle of the valley, which is here about a mile wide, 

 penetrated 400 feet of clay, sand and fine gravel, and w as abandoned without 

 reaching bed rock, from which it appears that the morainic tilling of the old 

 channel is at least 800 feet thick. Many copious springs burst out on the 

 steep slope of the gravel bed, forming small streams that unite with the Vesper 

 brook which comes in from the west through a deep ravine, and over a cascade 

 seventy feet high, and together make the Onondaga creek. The water of these 

 springs is saturated with lime taken up from the drift, and large masses of 

 travertine have been deposited in many places. An extensive deposit of red 

 clay, the material of which is evidently derived principally from the red Salina 

 shales, lies nearly across the extreme south end of this lower section of the 

 vallev. From this point to Syracuse, about seventeen miles, the valley is 

 from one to two miles wide, the sides of the bordering hills sloping gently at 

 the base, but becoming precipitous and in many places rocky in the middle 

 portion, while the upper part is a succession of rounded eminences that rise 



