Greatest depth. 

 210 G 



70 G 



87 G 

 87 G 

 25 G 



618M 

 435 M 



292 D. F. Lincoln — Glaciation in the 



Altitudes and Depths of Lakes. 



Elevation above tide. 



Erie 572-9 L 



Chautauqua .■ 1291 G 



Conesus 821 R 



Hemlock 898 R 



Canadice 1099 R 



Honeoye less than Hemlock 



Canandaigua 668 G 



Keuka (Crooked) 718' 10" G 



Seneca 441 C 



Cayuga 378 C 



Owasco 670 G 



( 860 G 



Skaneateles . . . . \ 864' 12" 



(861 C 



Otisco .. no data 



Cazenovia 900 G 



Schuyler 1200 G 



Otsego 1193 G 



Onondaga .. 361 G 



f 369 G 



Oneida ■] 367*71 



( 368 C 



Ontario 246 L 738 



L = U. S. Lake Survey. C = Resurvey of 1ST. T. Canals. R = Rochester 

 "Water Works Surveys. P = Perm. & N. Y. R. R. G- = French's Gazetteer of 

 N. T., 1860 (comparatively poor authority.) M= Soundings given on map pub- 

 lished by Engineering Department of Cornell University. 



The entire basin may conveniently be divided into three 

 regions or zones, nearly corresponding with certain geological 

 formations. The northern zone (Silurian) is nearly level, with 

 a heavy mantle of drift ; it extends from the Ontario coast to 

 the northerly escarpment of the Corniferous limestone, which 

 is skirted by the line of railroad, passing through Auburn, 

 Geneva, Canandaigua, and Miller's Corners. The middle zone 

 comprises the moderate ascent of the lower Devonian, extend- 

 ing south from 6 to 20 miles from the railroad. The southern 

 zone, with steep slopes and deep valleys, comprises the Upper 

 Devonian (Chemung and Portage rocks), including on the east 

 the lower Devonian to Skaneateles. The zigzag dotted line of 

 the Tully limestone partially indicates the demarcation between 

 the two latter zones. The terminal moraine bounds the whole 

 on the south. 



