THE HAMILTON ASSOCIATION 6 1 



of the more ancient ones, known at the time of pubUcation as Lower 

 Silurians. 



The low swampy fields close to the Corporation Drain have 

 contributed as usual some interesting specimens of what we may call 

 flint flake fossils. I have already expressed astonishment at the 

 inexhaustible supply turning up annually there. A new drain on the 

 McVittie Farm throws considerable light on the matter since the 

 swamp was drained many years ago. It appears clear enough now. 

 That the plough has never penetrated deep enough to disturb the chert 

 beds (in situ) underneath was Dr. Spencer's view. While 

 admitting its probability, I felt inclined to believe the swamp water- 

 had rotted away the softer portion of the upper chert, leaving no 

 impression on the hard part composed of silex (flinty matter.) 



Both theories are quite erroneous. This new drain exposes 

 the thin flakes, embedded, in countless numbers, in a white stiff clay, 

 viz., the ground-up meal of local rocks, pulverized by the glacier. 

 When it retreated, while it left Moraines in some localities adjacent, 

 there it dropped what we now find resting on the chert beds below. 

 This escaped observation when the Corporation Drain was first opened. 

 When it was subsequently deepened, the layers removed would only 

 hide more effectually the matter originally thrown out. 



Water or Weather-ivorn Greenstones SLnd granites are sometimes 

 found with Xho. flint flakes. Occasionally the latter occur below, dis- 

 playing a similar conveyance as regards both. The boulder clay or 

 till of Europe in many places exactly corresponds with the clay 

 resting on our local chert beds, and underlying that ancient lake 

 beach, known to us as the Burlington Heights. 



The remarkable preservation noticeable to us in the beds at the 

 top of the escarpment of the glacial striae is mainly owing to the 

 resistance it offers to the penetration of surface water. The color 

 proves it was little affected by the stagnant marsh which existed 

 before the Corporation Drain was excavated, where bog iron pene- 

 trated and stained the flint red or yellow. It was absent, probably, 

 when the workmen were cleaning out the drain a few years ago. I 

 remarked the coloring was confined to isolated patches. I think, 

 therefore, I cannot be far astray in arriving at this conclusion. Many 

 of the large travelled Niagara boulders resting on the Barton Ridge 

 beyond the drain, as well as the till, have been removed by the 



