804. S& G. Williams—Dip of the Rocks in New York. 
the Tully has been submerged for more than four miles, it rises — 
again from the lake and makes an arch of 4°4 miles span and 
160 feet in extreme height, descending to the south at the rate 
of 80 feet to the mile and northward 67 feet per mile. On the 
opposite side of the lake, the limestone immediately north of 
the arch is nowhere fully submerged, but after continuing nearly 
horizontal for about three miles, rises into an arch of over six 
miles span, the highest observed point of which is 235 feet 
: southwesterly. From the same point southeastward to the most — 
southern exposure in the Owasco valley, there is a descent of 
_ 810 feet in nine miles, or 34 feet per mile. Some not very — 
0 feet per mile § 
that this is less tl 
f the Tully from 
OtROY 
