104 RURAL MICHIGAN 



lake facilitated shipment, where gravity could be 

 relied on to bring the rough stone from the pits to 

 the finishing mills beside the docks. The stone, 

 -when first extracted from its matrix, was readily 

 workable into any desired design by machine tools, 

 and then, when exposed to the air, dried and hardened 

 into a condition of great duration both as against 

 fire and weather. The many abandoned open pits 

 along the south shore of Lake Superior testify to 

 the very active demand once entertained for this 

 building-material, a demand now transferred to the 

 less sightly but more adaptable and cheaper concrete 

 construction. At present (December, 1931), there 

 remains only one active sandstone quarry operating in 

 Michigan, near Grindstone City, Huron County. 



From 1860 to 1916 Michigan produced 236,724,878 

 barrels of salt, valued at $98,815,061.^ The output 

 of salt in 1919 was 2,492,378 short tons. Salt was 

 one of the first mineral resources of Michigan to 

 whi-ch attention was given by the State Geological 

 Survey. Douglass Houghton, the first State Geo- 

 logist, was convinced of the presence of salt in the 

 Saginaw valley and he persuaded the legislature to 

 make provision for exploratory work under State 

 direction. Investigations were conducted both in the 

 valleys of the Grand and the Saginaw rivers, but 

 early results were not encouraging and State efl'orts 

 were discontinued. Some years later private agencies 

 resumed these investigations and by 1860 the definite 

 success of salt production in Michigan was estab- 



^ "Mineral Resources of Michigan," Lansing, 1916, p. 159. 



