TEE SALT-DEPOSITS OF WESTERN NEW YORK. 533 



It is stated that the superior strength of the Warsaw brine makes 

 it possible for one ton of coal to produce more salt, by sixty-four 

 cents' worth, than can be produced from the Syracuse brine. This fact, 

 together with the falling off in the Syracuse output, has called marked 

 attention to the Warsaw wells. 



The product of salt from the Michigan wells is over 15,000,000 

 bushels annually, on which the profit is large because the fuel consists 

 of slabs and sawdust, a mere nothing. An eminent authority — Dr. 

 Mitchell — states that there are three sources of the salt-supply in 

 Michigan : 1. In the coal-measures and in the white and porous 

 Parma sandstone, which serves as a reservoir. 2. The " Michigan Salt- 

 Group," which lies between the carboniferous limestone and the sand- 

 stones at the base of the carboniferous system. This group consists 

 of various shales, magnesian limestone, and beds of pure gypsum. The 

 material of the reservoir is Napoleon limestone. The depth of boring 

 is 600 to 700 feet, and the total area of the territory is about 17,000 

 square miles. 3. The " Onondaga " or Salina Salt-Group, which lies 

 500 feet below the Michigan Salt-Group, and in which alone are found 

 the beds of rock-salt. The most important well is that at Marine 

 City, on the St. Clair River, the total depth being 1,633 feet, and the 

 thickness of the salt-beds 115 feet. The well at Muskegon, on 

 Lake Michigan, is 2,000 feet deep, and the thickness of the salt-beds 

 is 50 feet. Other important wells are operated at Bay City and at 

 Manistee. 



Similar beds are found in the Province of Ontario, at Goderich, 

 Huron County. They are in the Salina formation also, the depth 

 averaging about 1,000 feet, and the thickness of the salt about 30 

 feet. Exceptionally deep wells have been driven to a depth of 1,600 

 feet through six layers of salt aggregating 125 feet in thickness. The 

 salt area of Canada is estimated at 2,000 square miles, and the proba- 

 ble quantity of salt still in the beds is called 200,000,000,000 tons. 

 The Canadian salt is superior to the Michigan salt in regard to 

 the absence of the earthy chlorides, as the following analysis will 

 show : 



The salt-beds of Michigan underlie each other like a nest of saf- 

 cers — the oldest being in the old dolomite limestones in the ancient 



