CARBONIFEROUS LIMESTONE. 121 



stone on Crawford's farm have been used for lime-burning, but at 

 present the kilns lie idle. The islands of Saginaw Bay, lying in 

 front of Wild Fowl Bay, are all underlaid by this limestone forma- 

 tion. On several of them, particularly on Mr. Heinzelman's Island, 

 quarries are opened which provide the cities along Saginaw River 

 with the necessaiy stone for foundation walls and like purposes. 

 To supply a local demand, a portion is converted into lime. 



