86 Dr. Bigsby's Sketch of the Topography 



Indian Hut Island, the only one remaining which requires 

 distinct notice, guards the mouth of Goose Creek Bay. It is 

 rocky, a mile and two thirds long, and from six hundred to 

 seven hundred yards in average breadth. It is 360 yards from 

 the eastern outer angle of the bay. It belongs to the United 

 States. 



The Geology of Lake Ontario. 



The situations where the loose transported matters covering 

 the fixed rocks of Lake Ontario particularly abound, have 

 been noticed ia the topographical part of this paper, and the 

 inferences they lead to have been stated in the general view of 

 the detritus of Canada, read before the Geological Society of 

 London in the winter of 1826-7. 



While the parallel ridge west and south of the lake is com- 

 posed almost wholly of rock, the eminences bordering this 

 body of water on the north-west are formed of these later de- 

 posits, which also overspread in great thickness the interval 

 of thirty-seven miles between Lakes Ontario and Simeoe, and 

 near the latter of which are penetrated for two hundred feet 

 by the River Holland at Robinson's Mills. At that place, a 

 hard well-cemented conglomerate of small primitive pebbles 

 is now forming near the water level. It was altogether out of 

 my power to make any very accurate observations on the na- 

 ture and position of the component parts of the highlands of 

 York and their vicinity alluded to above. I landed at the 

 highest part of the cliffs six miles east of York, and found the 

 castellated masses there to be of brown marl, effervescing 

 smartly on exposure to acids, tolerably firm in its texture, and 

 full of very small fragments of black limestone. But in the 

 greater part of these heights, the lower half or thereabouts is 

 occupied by a dark blue substance, either a clay or marl, and 

 a yellow material which I take to be sand. This is particularly 

 striking in the second bay from the east. In several places 

 along-shore, about the middle of this line of precipices the beds 

 of sand and clay seem to alternate. There is here so large an 

 accumulation of diluvium, and it is so freely exposed by nu- 

 merous and deep ravines, that it must be a very favourable spot 

 for the discovery of animal remains : some of which indeed 

 have been discovered in Lake Erie. 



Boulders, numerous and of great size, abound everywhere. 

 They are chiefly primitive, and can be referred to their parent- 

 rock in many cases, as in the instance of the milky quartz 

 near Kingston, which extends in rolled fragments even to Lake 

 Erie, having ascended the heights of Queenston. The re- 

 markable augitic trap of Montreal is found in the Genesee 



Country ; 



