56 Observations on ih.e Suuilt Sole of Ontario Valley, 



the valley of Tonawanta creek. All Grand Island, and tlie small 

 ones around it are of this clay bed. It may be traced far west on 

 the Chippewa and over on the Grand river. 



The lime stratum of Niagara Falls, with shells, is of very great 

 extent, particularly eastward. Over it falls the Oak Orchard 

 creek, Genessee river, Canandaigua outlet, Seneca outlet, and the 

 streams from the lakes Owasco, Skaneateles, and Otisco, and it 

 may be traced as far east as the falls of Skanado creek in Oneida 

 county. The terminating edge of this lime stratum, is generally 

 very straight, and varies but little from an east and west course. 

 For the first 20 miles east of Niagara river, it ends in a denudated 

 rock, projecting so much, that when tracing the level of the surface 

 of lake Erie along the north side of it, in 1810, it was found a very 

 convenient shelter from the showers. 



Mr. William Smith and his followers observe of the British stra- 

 ta, that in all the eastern parts of England, they " end successive- 

 44 ly towards the N. W., generally with a fingered or digitated out- 

 44 line, running out into ridges, beyond the general range of the 

 44 edge or limit of the stratum." The outline or terminating edge 

 of this great lime stratum, which is such a distinguishing feature 

 in the south side of the great Ontario valley, is towards the north, 

 and instead of a fingered form, thus, 



^fy^^^gl^!^^ may be repres ented 



calling the side above the line, the terminating edge or ending, as 

 Mr. Smith would term it. This formation, as has been mentioned, 

 is more particularly to be observed between the Niagara river and 

 the 18 mile creek. In almost all the indents or chasms that run 

 back, south of the general range of termination, streams run from 

 the level table-land above, and by wearing their respective chasms, 

 have given them the appearance of being formed by the action of 

 said steams. That all these ravines have been scooped out by the 

 agency of streams that occupy them, would be readily conjectured 

 by every superficial observer, more particularly the one in whicli 

 runs the Niagara river. 



At the head springs of the 18 mile creek, it is shown to be other- 

 wise. From three of these indents, the west branch of the 18 

 mile creek is formed as sketched below. 



