16 TUB CANADIAN NATURALIST. [March 



greater, exceeding by an unknown amount, in these localities, 854 

 and 700 feet. The Corniferous at its outcrop in Woodhouse, 

 twenty-five miles to the east of Tilsonburg, measures only 

 ] GO feet thick, so that there is evidently, in the localities just men- 

 tioned, a great increase in the volume of the Salina formation 

 from the 300 feet observed in western New York. At Goderich, 

 on Lake Huron, the thickness of this formation is much greater. 

 Here are found non-fossiliferous strata, having the character 

 of the so-called Water-lime beds, which belong to the summit 

 of the Salina formation, and are immediately overlaid by 

 fossiliferous strata belonging to the Corniferous formation. 

 At this point a boring in search of petroleum penetrated not less 

 than 775 feet of solid white, gray and blue limestones, chiefly 

 magnesian, with occasional thin beds of sandstone. Below this 

 depth the strata consisted chiefly of reddish and bluish 

 shales, with interstratified beds of gypsum, sometimes ten feet in 

 thickness. After the 164 feet of these, rock-salt was met 

 with, interstratified with clay, through a distance of forty-one 

 feet, beneath which the boring was carried five feet in a solid 

 white limestone, probably belonging to the underlying Guelph 

 formation. We have thus, for the entire thickness of the Salina 

 formation at Goderich, 980 feet, of which the upper 775 are hard 

 strata, chiefly magnesian limestones, and 205 feet gypsiferous 

 and saliferous shales. Several wells since sunk in this vicinity, 

 one of them twelve miles to the south-westward, have given almost 

 identical results, including the mass of rock-salt at the base. 

 These borings now yield, by pumping, a copious supply of brine, 

 nearly saturated and of great purity, so that this newly discovered 

 saliferous deposit has already attracted the attention of salt 

 manufacturers, both in Ontario and New York. A detailed 

 description of the first well, with an analysis of the brine, will be 

 found in the Geological Report for 1866, already referred to. 



Brines are said to have been met with at tliis horizon in 

 Michigan, where the formation will probably be found to have a 

 much greater thickness than that hitherto assigned to it. 



It thus appears that the Salina formation, after being reduced 

 to less than 300 feet at the Niagara river, again assumes, to the 

 north-westward, a thickness of nearly 1,000 feet, and becomes 

 once more salt-bearing, as in the State of New York. The in- 

 creased thickness of the formation, in these two regions, connect- 

 ed with accumulations of salt at its base, would seem to point to 



