APPENDIX 
( A. ) 
Riclge Road of Lake Ontario. 
The elevations given of the Ridge Road bordering Lake Ontario, shows no important variations 
within the limits of the Fourth District. Since that portion of the Report passed through the press, I 
have had an opportunity of examining a continuation of the same, or another similar ridge, in the 
northern part of Oswego and the southern part of Jefferson counties, and about six or eight miles 
distant from the shore of Lake Ontario. This ridge is about four hundred feet higher than the lake, 
but having been traced only for a few miles, it is impossible to say whether it continues at a uniform 
elevation. I am aware that this discrepancy in the elevations between this portion and that in the 
western part of the State, has been urged as an objection to the supposed mode of its production. I 
consider, however, that the existence of such a ridge, with all the attendant phenomena before noticed, 
is paramount to every objection regarding its mode of formation; and different elevations of different 
portions do not in the least impair the force of the conclusion. 
In the example before us, it offers a fact in proof that the lake was not quietly drained by the 
reduction of the barrier at its outlet, but that the change has taken place by an elevation of the land. 
The varying elevation of the ridge proves that the amount of upheaval was greatest towards the north¬ 
east, in the region of a nucleus of hypogene rocks, and that it gradually subsided towards the south¬ 
west, where the strata become undisturbed. 
It is not improbable, however, that further investigations will prove the existence of a series of 
parallel ridges in New-York, showing the effects of successive elevations, aided likewise by a reduction 
of the outlet. 
The different elevations of the well marked Tertiary deposits, upon the valley of Champlain and 
the St. Lawrence, as well as those upon the New England coast, become interesting in connexion with 
this subject; and, as before suggested, it is not improbable that future investigations will prove the eleva¬ 
tions of these deposits, and the production of the lake ridges, to be synchronous, at least to a certain 
extent. Still it is very probable that some of the more elevated ridges may have emerged before any of 
the marine tertiary appeared above the level of the Ocean. 
[Geol. 4th Dist.] 83 
