THE NONMETALLIC MINERALS. 199 



Dr. Engelhardt's report/ At Morrisville, in Madison County, it is 

 12 feet thick and at a depth of 1,259 feet; at Tully, in Onondaga 

 County, it varies from 25 to 318 feet, at depths of from 974 to 1,465 

 feet. The seven beds found at Ithaca have a total thickness of 248 feet, 

 the uppermost lying at a depth of 2,244 feet. In the Genesee Valley 

 the beds vary in depth from T50 to 2,100 feet and in thickness from 40 

 to 93 feet. In the Wyoming Valley the depth varies from 610 to 2,370 

 feet below the surface and in thickness from 12 to 85 feet.^ 



Mlcklgan. — The salt-producing areas of this State are, so far as 

 now known, limited to the counties of Iosco, Bay, Midland, Gratiot, 

 Saginaw, Huron, St. Clair, Manistee, and Mason, the beds of the 

 Saginaw Valley lying in the so-called Napoleon sandstone, at the base 

 of the Carboniferous. Professor Winchell has estimated this forma- 

 tion to cover an area of some 17,000 square miles within the State 

 limits. The beds of the St. Clair Valley, on the other hand, are in 

 Upper Silurian strata, being presumably continuous with those of 

 Canada. The manufacture of salt from brines procured from these 

 beds began in the Saginaw Valley in 1860 and has since extended to 

 the other regions mentioned. According to F. E. Engelhardt the 

 rock salt deposits in the Upper Silurian beds, with a thickness of 115 

 feet, were reached at Marine City, in St. Clair County, at a depth of 

 1,633 feet; at St. Clair, St. Clair County, at a depth of 1,635 feet and 

 with a thickness of 35 feet. At Caseville, in Huron County, the beds 

 lie at a depth of 1,164 feet, and at Bay City, Saginaw Bay, at 2,085 

 feet, the salt beds being 115 feet in thickness. At Manistee the bed 

 is 34 feet thick, lying 2,000 feet below the surface, while at Muskegon, 

 in the Mason well, it was 50 feet thick at a depth of 2,200 feet. 

 Although of so recent development, Michigan is rapidly becoming one 

 of the leading salt-producing regions of the world, the estimated manu- 

 facturing capacity being now upward of 5,000,000 barrels annually. 

 The total product of all the years since 1868 is given as 60,614,464 

 barrels of 280 pounds each. 



In Kansas the rock salt occurs in beds regarded as of Permian age, 

 and has been reached by means of shafts in several counties in the 

 southern and central part of the State. The following is a section of 

 a shaft sunk at Kingman in 1888-89: 



Feet. 

 "Red-beds," red arenaceous, limestones, ferruginous clays, and clay shales 



with thin streaks of gray shales and bands of gypsum as satin spar 450 



Gray or bluish ' ' slate, ' ' with 2 feet of limestone at 500 feet 140 



Red clay shale 4 



Gray "slate," with occasional streaks of limestone, 2 to 8 inches thick, and some 



salt partings and satin spar with ferruginous stain 78 



^The Mineral Industry, its Statistics and Trade for 1892, by R. P. Rothwell. 



^ For a very complete historical and geological account of these salt beds and the 

 method of manufacture, see Bulletin No. 11, of the New York State Museum, 1893, 

 by F. J. H. Merrill. 



