THE GORGE OF THE AAR AND ITS TEACHINGS 141 



I refer to this argument, because, since my articles first 

 appeared, I have received from two American geologists 

 copies of papers showing that similar features have been 

 observed in some of the American valley-lakes, and the 

 same general conclusion has been drawn from them. In a 

 paper on " Glaciation in the Finger Lake region of New 

 York," by Dr. D. F. Lincoln (in the American Journal of 

 Science, vol. xliv., October, 1892), it is shown that Seneca 

 Lake is bordered through a great part of its circumference 

 by vertical cliffs of rock, that it undulates in moderate 

 curves, and that inflowing streams with rocky beds enter 

 it, either near the level of the water or at a considerable 

 elevation. In some cases a lateral stream flows over 

 nearly level ground to the cliff-edge without any valley 

 banks, suggesting that the main valley occupied by the 

 lake was formerly at this high level. The conclusion is 

 reached that this and other lakes with similar characteris- 

 tics have been " deeply gouged by ice." In a later paper 

 (dated August, 1893) he notices the absence of side-valleys 

 along Seneca and Cayuga Lakes, and points out the 

 remarkable difference in this respect between these lakes 

 and valleys situated south of the great moraine, which 

 latter are " notched down to the flood-plain level every 

 mile or two," while " the lake-side for stretches of ten 

 to fifteen miles seems like an artifically smoothed garden 

 slope." 



In the Bulletin of the Geological Society of America, vol. v., 

 pp. 339—356 (March, 1894), Mr. Ralph S. Tarr has a 

 paper on " Lake Cayuga a Rock-basin," illustrated by a map 

 and section. He maintains that Lake Cayuga is situated 

 in a rock-basin, about 435 feet deep, and formed by glacial 

 erosion ; the proof being that the pre-glacial tributaries of 

 the valley are rock-enclosed, and that tlieir loivest points are 

 above the present lake-surface. The map shows all the lakes 

 of this region to have the very same kind of contour as 

 that on which I founded my argument. 



I venture to hope that the brief sketch I have here 

 given of one of the grandest and most interesting valleys 



