SALT ENTERPRISE IN MICHIGAN. 275 



tion, making a deep indentation in the peninsula, and 

 occupying a denuded space in the sandstones just at that 

 point where the latter comes in contact with the lime- 

 stone of the north" (p. 10). * * * "These hills [the 

 highlands of the Au Sable] follow the line of bearing of 

 the rock formations, and no doubt extend diagonally com- 

 pletely across the state " (p. 6). 



These, and numerous similar expressions in his reports, 

 are entirely inconsistent with that dish-shaped conforma- 

 tion which we have found to exist, and inconsistent with 

 any conception of a " salt basin " in the state. The first 

 foreshadowings of any basin arrangement are found in 

 the reports of Mr. C. C. Douglass and Mr. Bela Hubbard, 

 dated January 4 and January 24, 1841. Mr. Douglass 

 remarks that " the same rocks, with one or two excep- 

 tions, occur on both sides of the state, having the same 

 geological position ; also, they have very nearly parallel 

 and uniform positions" (p. 103). This seems to contem- 

 plate the existence of a synclinal trough running north 

 and south across the peninsula. Mr. Hubbard, however, 

 traces the outcrop of the Coal Measure rocks from east 

 to west across the southern part of the peninsula, and 

 thus more distinctly shadows forth the conception of a 

 basin structure (p. 125). He says, moreover, "All the 

 rocks on the eastern slope of the peninsula south of Sagi- 

 naw Bay have a general dip northwesterly, while the dip 

 along the southerly and westerly border of the basin of 

 coal-bearing rocks is such as to indicate the counties of 

 Clinton and Gratiot as occupying nearly the central part 

 of the coal basin" (p. 137). This, indeed, is a recognition 

 of a basin structure, but it locates its center more than 

 fifty miles southwest of the Saginaw valley. Moreover, 



