182 E. C. QUEREAU—JAMESVILLE LAKE, NEW YORK. 
considerable. The network of perpendicular and cross fissures have in 
places cut blocks of the rock entirely loose, so that they tilt when one 
steps upon them. The fissures, with their cave-like expansions, would 
in this and other ways undoubtedly assist materially in hastening the 
removal of the rock by running waters. It does not seem probable, how- 
ever, for a number of reasons, that this is to be considered the chief or 
even a very prominent factor in comparison with the work of running 
waters. Thus the outlines of the depressions are too regular and their 
form too symmetrical for them to have been cave chambers, at least un- 
less they have subsequently been much modified by other agencies. 
There are some two dozen of the depressions lying in the abandoned 
watercourses of this region, but outside of these watercourses the sur- 
face of the country all about is free from them. In the whole region 
where the depressions are so abundant only one or two caves are known 
and these are smaller than the great majority of the kettles and of very 
different form; while on the other hand, in other parts of the county, 
where caves of larger size are reported, sinkholes or kettle-like depres- 
sions are not known. 
The formation of gorges like the Jamesville gorge and Rock gorge, the 
carrying of such large amounts of fragmental material as are found at 
the east end of these gorges and the carving of these into terraces which 
rise 50 to 60 feet above the gorge bottom could certainly not be ascribed 
to cave streams. A short distance east of Jamesville lake, Oriskany sand- 
stone and the Corniferous limestone are not found in place, as explained 
above, and yet we find blocks or boulders of these rocks 3 and 4 feet 
long which have been transported half way down the gorge. These facts 
point also to powerful water'action. The conditions found in Rock gorge 
confirm our conclusions as to the former presence of large and powerful 
erosive water currents. Our conclusion is, therefore, that the kettle-like 
depressions at and about Jamesville lake were formed, like the terraced 
channels in which they lie, chiefly through the action of postglacial 
streams, aided in some degree by percolating waters, which produced 
a network of fissures and cave-like openings in the rocks and thus ren- 
dered them a more ready prey to the action of eroding streams. If this 
diagnosis shall prove to bea correct one, the term “ pothole lake” would 
perhaps not be inappropriate. 
It is not intended to have it implied by what was said in the begin- 
ning that all the small, “round” lakes of the state are necessarily of the 
same origin as Jamesville lake. I am not sufficiently well acquainted 
with the class to be able to say to what extent this may be the case. I 
am, however, quite sure from what I have’seen that Jamesville lake is 
not the only one of its kind in this part of New York. 
