PETEOLEUM IN ONTARIO. 109 



Ontario, where their increase or decrease goes on at pretty regular rates, so that we are 

 able to predict with tolerable accuracy the depth at which any one of them may be 

 found by boring at a given locality. 



Dr. T. Sterry Hunt, in his valuable Report for 1866, has put on record the " logs " of â 

 large number of wells which had been bored up to that time in western Ontario, and 

 which would have been otherwise lost. It is to be regretted that the registers of the still 

 greater numbers of wells which have been sunk since that time, have not been systema- 

 tically preserved. In regard to general deductions, from information obtained by well- 

 boring, the extensive experience of our neighbors in the analagous regions of Ohio and 

 Michigan, is of great value to us. 



The petroleum of the Enniskillen region has hitherto been supposed to have origin- 

 ated in the Corniferous formation, biit from circumstances which have lately come to light, 

 it seems possible that it may have its origin, wholly or in part, in the Trenton limestone. 

 Without necessarily adopting this view, the writer may mention the following, among 

 other circumstances which appears to faA'or it : — 



(1). The Trenton limestone along the Cincinnati anticlinal has proved to be eminently an 

 oil-producing formation in north-western Ohio, as well as near Barksville and elsewhere 

 in Cumberland County in Kentucky, where great flowing wells of petroleum were found 

 in boring for brine in 1829. Wells sunk in the same region in later years have yielded 

 large quantities of oil. (Dr. Hunt's Report for 1866, p. 253). This formation is not likely 

 to have lost its oil-producing character within a short distance on passing into Canada. 

 On the contrary, we know that much further to the north it yields petroleum on Mani- 

 toulin Island, where the writer has seen wells drilled into it near Wequimakoug and at 

 Pike Lake. Petroleum, or pitch resulting from it, are found in this formation in other 

 parts of the Dominion. At one of these localities near Chicoutimi on the Saguenay, where 

 petroleum exudes from the Trenton limestone, gallons of it have been collected, by 

 breaking open the cavities in the rock. Again, to the west, the Lower Silurian limestones 

 in the vicinity of Chicago, are said to hold petroleum. 



(2). The Trenton formation is of a more generally bituminous character than the Cor- 

 niferous, and it is also much thicker. In various parts of the provinces of Quebec and 

 Ontario it ranges from 600 to ^50 feet in thickness, including the Black River and Birds- 

 eye, but not the Utica ; and at Findlay in Ohio, the drill has passed through 550 feet of it. 

 (Prof. Orton's Report, p. 18.) 



(3). In the States of New York and Ohio, the Corniferous is not a petroleum-bearing 

 formation. Although oil has been observed in its cavities in some places in the south- 

 western part of Ontario, there is nothing to show that it was originally formed in these 

 rocks. Its thickness in western New York is only ninety feet, but in the townships 

 of Woodhouse and Townsend in Ontario, seventy miles west of Niagara River, it has 

 attained 160 feet. In Ohio, its thickness is from 75 to 1*75 feet, and at Mackiuaw, in the 

 northern jiart of Michigan, it is 275 feet. In south-western Ontario, well-borings have 

 given the following thickness for limestones believed to represent the Corniferous : Port 

 Lambton, 820 feet ; Petrolia, 248 and 878 ; one mile south-west of Belle River, 209 ; Leam- 

 ington, 310 ; bx;t it is difficult in all cases to draw a line between the limestones of this 

 formation and those of the underlying Lower Helderberg or upper part of the Onondaga 

 (salt) formation. For example, the following thickness of limestones were obtained in 



