438 H. L. FAIRCHILD — GLACIAL GENESEE LAKES. 



road near Belvidere. The higher was estimated as in the neighhorhood 

 of 150 feet above the river plain, or about 1,520 feet ; it is probably higher 

 rather than lower, as such estimates of distant points usually fall under 

 the truth. 



At Caneadea there are several distinct high levels of erosion, the lower 

 ones belonging to the next stage of the static waters. The highest level 

 upon the west side of the valley is upon a kame or moraine deposit, which 

 dammed the lateral valle}'' and produced the tributary morainal Rush- 

 ford lake (see page 451), and the level is believed to belong to that local 

 lake. A lower terrace on the river side of the moraine is believed to be a 

 delta of the Rushford lake outlet or a plane of the Genesee waters, at 

 an altitude of 1,514 to 1,530 feet (aneroid, with spirit-level). 



At Fillmore the lower of the elevated terraces Avere measured by spirit- 

 level and a careful estimate of the added height of the distant summit 

 terrace gave a result for the latter of somewhat more than 1,500 feet. 



FIFTH STAGE: PORTAOEVILLE-NUNDA LAKE. 



Outlets. — The immediate or ])rimary outlet was b}'- the up})er Canase- 

 raga cliannel, the waters falling into Dansville lake. The ultimate outlet 

 was by the Burns channel to the Chemung — Susquehanna. 



General description. — In connection with this and the succeeding stage 

 there is a complication of conditions and phenomena making a difficult 

 but fascinating problem. For the understanding of the matter by the 

 reader it is necessary to describe the main topograi)hic features of the 

 district comprised by a circuit of Portageville, Nunda, Canaseraga, Dans- 

 ville and Mount Morris, and give an outline of the history. 



At Portage gorge the river dro})S into its postglacial cliannel, reaching 

 to Mount Morris. Upon the west the land is high. Upon the east the 

 ridge dividing the Genesee channel from the broad, low valley of the 

 Kishawa creek (Nunda valley) is lower, ranging from 1,100 down to 800 

 feet. The present Kishawa valley heads in a lieavy moraine south of 

 Nunda village and a branch leads southeast to a col. From this col, a 

 few miles north of Swains station, a fine rock channel leads south and 

 then east to Canaseraga village. In this old, abandoned river channel 

 rises the Canaseraga creek, which, one mile east of Canaseraga village, 

 drops into the gorge locally known as Poags Hole ; then a few miles north 

 emerges into the broad Dansville valley and finally joins the Genesee 

 river near Mount Morris. The main divide between these waters and the 

 Susquehanna waters is at the head of Poags Hole, one or two miles north 

 of Burns station on the Erie and the Central New York and Western 

 railroads. 



The history in brief seems to be as follows : Before the Cuba outlet 



