122 J. W. SPBNCEE ON 



the large amount of difFerential elevations in their heights indicated great warping in 

 recent geological times. Only a note upon the subject was published ' by Mr. Gilbert,- 

 but I have here to acknowledge my indebtedness to him for the measurement of many 

 X-)oints and other information. 



The writer has followed the beaches on the Canadian side of the lake, and in north- 

 eastern New York beyond the region of Mr. Grilbert's observations. The discoveries 

 made are of great importance, especially in the study of origin of the Great Lakes — a 

 study commenced by the writer ten years ago. In the investigation of this subject, 

 there are two great questions : the origin of the valleys, and the cause of the valleys 

 being closed to form water-basins. With the first of these, this paper has nothing to do. 

 With regard to the latter, Gen. Warren was the first to propose the hypothesis of warping 

 towards the north and east (1875) ' in explanation of the closed basin of Ontario, as well 

 as other basins of the Great Lakes. I accepted the hypothesis — now a theory — and 

 defined the St. Lawrence valley as only a broad continuation of the ancient Ontario 

 valley. The discovery of difFerential elevations in the region of the present outlet, was 

 the first definite proof that most of the warping, assumed by the author, had been 

 produced since the waters of the lake were confined to a basin separated from the other 

 "•reat lakes. In the sea-cliffs, east of Watertown, the inscription of older and greater 

 difierential changes of level can be read, so that the closing of the Ontario basin is no 

 longer a mystery or an hypothesis. Lake Ontario was formerly included in the union 

 of Lakes Huron, Erie etc., which, as jjointed out long ago by the writer, formerly existed as 

 one sheet of water, out of which rose the highlands of Ontario, now standing 1,700 feet 

 above the sea, surrounded by elevated beaches. As reference will be made to this sheet, 

 when all the lakes, in an expanded and united form, stood at the same level, I will name 

 it Lake Wabren, in honor of the late Gen. G. K. Warren, Corps of Engineers, U. S. A. ; 

 whose discovery, in 187-5, that Lake Winnipeg was formerly of great size, occupying the 

 Red River valley in Minnesota and Manitoba, and explaining its existence by difFerential 

 elevation or warping of the earth's crust — which explanation he extended to the 

 Great Lakes — entitles him to be regarded as the father of lacustrine geology in America. 

 The limits of Lake Warren are here defined as that body of water which existed in the 

 Great Lake region from the time that there was the barrier between it and Hudson Bay, 

 sufiiciently high to have held in the waters on the northern side (even though an outlet 

 in that direction should be found), and the time when Lake Ontario was separated from 

 it by a change of level in its surface. The name of Gulf of Warren is here given to the 

 enlarged body of water, before its more complete separation from the sea. The barriers 

 to the south will be explained in a subsequent paper. Since the separation of Lake 

 Ontario from Lake Warren, there has been only one great epoch of rest in the subsidence 

 of its waters — marked by the beach (or a small series of beaches) under consideration. 

 In designating geological features, I am averse to giving names, necessarily non-descrip- 

 tive. But the better method of using geographical names ought not to be adopted arbi- 

 trarily. In this case, there are but two local names that seem to have claim for preference 



' At time of writing tliis paper, Jan. 1888, 

 '^ Report of Proc. A. A. A. S., Science, Sept. 1885. 



■' Appendix J, Report of Ctiiof of Engineers, U. S. A. 1875. See also " Surface Geology of tbie Region about 

 the Western End of Lake Ontario," by J, W. Spencer, in Canadian Naturalist, Montreal, 1882, 



