No. 5.] SPENCER — SURFACE GEOLOGY. 265 



SURFACE GEOLOGY OF THE REGION ABOUT THE 

 WESTERN END OF LAKE ONTARIO. 



By J. W. SpkxNcer, B.A.Sc, M.A., Ph.D., F.G.S., 

 Vice-President of the University of King's College, Windsor, Nova. Scotia. 



(For previous parts, see this Journal, Vol. X., Nos. '.) and 4.) 



At the time when the " Preglacial outlet of the Basin of Lake 

 Erie, &c." was written (Feb. 1881) I felt confident that the 

 Presrlacial outlet of Lake Ontario would be more or less easily 

 revealed, and therefore neglected to give due consideration to the 

 erosion that would be effected by the action of the rain and rain- 

 water. This may well be summed up by quoting from a criticism 

 on my above mentioned paper, by Prof. J. P. Lesley, the Direc- 

 tor of the Geological Survey of Pennsylvania^' •' For a number 

 " of years I have been urging upon geologists, especially those 

 " addicted to the glacial hypotheses of erosion, the strict analogy 

 " existing between the submerged valleys of Lakes Michigan, 

 " Huron and Erie, and the whole series of dry Appalachian 

 " ' Valleys of VIII,' stretching from the Hudson river to 

 " Alabama ; also of Green Bay, Lake Ontario and Lake Cham- 

 " plain, with all the dry ' Valleys of II and III.' One single 

 " law of topography governs the erosion of them all, without 

 " exception, whether at present traversed by small streams or 

 " great rivers or occupied by sheets of water ; the only agency 

 " or method of erosion common to them all beine; that of rain 

 " water ; not in the form of a great river, because many of them 

 *' neither are now nor ever have been great water-ways. As a 

 " consequence of their absolute similarity of geological position, 

 " general form and common genesis, their age must be one and 

 " the same. The sea has had nothing to do with their production 

 " for it has permanently invaded some of them, or even 

 " temporarily others. Ice has had nothing to do with their 



* See Report Q4 of that Survey, 1881. 

 Vol. X. R 2 No. 6. 



