No. 8.] SPENCER — GEOLOGICAL SKETCHES. 463 



GEOLOGICAL SKETCHES OF THE NEIGHBORHOOD 



OF HAMILTON. 



By J. W. Spencer, Bac. App. Sc. 



The country in the vicinity of Hamilton, Ontario, affords a 

 very interesting field to the geologist. Within a limited dis- 

 tance there are excellent exposures of the upper members of the 

 Medina, as well as of the Clinton, and the lower part of the 

 Niagara formations. These reward the persevering collector 

 with a goodly number of fossils, besides several mineral species. 

 The superficial geology of the region in question is likewise well 

 worthy of study. 



The most prominent feature of the Western Peninsula is the 

 Niagara Escarpment (popularly called at Hamilton " the Moun- 

 tain"), which, crossing into Canada at Niagara Falls, skirts the 

 western end of Lake Ontario, and extends northward to the 

 Manitoulin Islands. The escarpment rises several hundred feet 

 above Lake Ontario, sometimes forming abrupt cliffs, and at 

 others having a more gradual ascent. At Hamilton it is about 

 two miles from the lake, or rather from Burlington Bay, and 

 396 feet above the bay, or 628 feet above the sea. West of the 

 city it recedes eight or nine miles from the bay, the north side 

 of which it, however, again approaches, forming the valley in 

 which Dundas is situated. 



The object of this paper is to give a few facts concerning the 

 strata composing this escarpment in the neighborhood of Hamil- 

 ton, together with notes on the superficial geology, mineralogy, &o. 



The Medina Formation. 



This formation has only its upper members exposed at Hamil- 

 ton, although at Oakville, on the north side of the lake, the 

 lower beds are seen, being underlaid by the Hudson River 

 rocks. The whole thickness is estimated by the Geological 

 Survey at 614 feet, of which only about 100 feet of the upper 

 part are seen at Hamilton, and still less at Dundas. The whole 

 formation consists essentially of shales with some sandstones. 

 Near the summit is the " Gray Band," a fine-grained and irregu- 

 larly deposited sandstone, with a thickness at Hamilton varying 

 between seven and fourteen feet. Above this there are eight 

 feet of impure, slightly calcareous sandstones, in thin beds with 



