110 in li'AL MICUJOAN 



the southern peninsula of Michigan. The Survey 

 regards this as probably less than one-fourth of the 

 total number in this peninsula. Some deposits are 

 1,000 acres in extent and have an average depth of 

 twenty or more feet. The Upper Peninsula also has 

 marl deposits. IMarl is found in twenty-two counties 

 of the State. The total area is estimated at 27,000 

 acres. Some of these marl deposits are unfavorably 

 situated for development, but many others are ad- 

 vantageously located and are at present being ex- 

 ploited in the manufacture of cement. Shale is 

 distributed very widely throughout the State, often 

 in close association with other raw materials required 

 in cement making. Cement manufacture began in 

 Michigan in the early seventies at Kalamazoo, where 

 marl and clay were employed in a vertical kiln. 

 While this enterprise was a financial failure, other 

 plants sprang up and the industry developed very 

 rapidly after l(Si)5. The later stage of the industry 

 involves the use of rotary kilns and powdered coal 

 as fuel. Since 1S!)(!, thirty-five cement plants are 

 said to have been built or projected in Michigan, 

 of which eleven were still in operation in 1917. Of 

 these eleven, six were using marl and clay, and five 

 limestone and shale. Cement plants have been lo- 

 cated at Alpena, Fenton, Bellaire, Bellevue, Bronson, 

 Coldwater, Kalamazoo, Elk Rapid.s, Farwell, White 

 Pigeon, Charlevoix, Marlborough, Bay City, Lupton, 

 Chelsea, Cement City, Spring Arbor, Lakeland, 

 Athens, Three Rivers, Gray Village, Wyandotte, 

 Xewago, Mocherville, Union City, Petoskey, Man- 



