No. 4.] CLAYPOLE — PRE-GLACIAL GEOGRAPHY. 227 



APPENDIX, 



As any contribution however small to the Preglacial Geography 

 of the lake reoion and the course of the old 'Mohawk must 

 possess some value I add the following : 



During the summer of 1877 when on the St. Lawrence I met 

 one of the inspectors on the new Welland Cannal. In the course 

 of conversation he mentioned that some difficulty had been found 

 in choosino; a site for Lock No. 1, Port Dalhousie. Visitins; the 

 spot soon afterwards he explained to me that where it was at first 

 intended to construct this lock no rock could be found by probing 

 the soil except at the southern end. It was consequently deter- 

 mined to remove the site back from the lake about the length of 

 the lock in order to place it on a solid foundation. Lock No. 1, 

 therefore now stands upon the very edge of a buried cliff, its 

 north-western corner projecting beyond the line and being sup- 

 ported on piles. The same gentleman also informed me that at 

 the distance of a few feet from the lock-sill towards the lake a 

 rod was sunk to the depth of forty feet through soft ooze or peat 

 without finding anything solid. 



It may be that we have here another small link in the chain 

 of evidence which will some day map out for us the Preglacial 

 Mohawk. This buried cliff it should be remembered is below 

 the water level of Lake Ontario and consequently more than 300 

 feet below the surface and about 100 feet below the bottom of 

 Lake Erie, and of the buried channel of Detroit. It would 

 therefore appear as if there may have been a swift current or 

 possibly rapids between these valleys in Preglacial times as there 

 is now. 



