CLAYS, SHALES, AND SLATES. 



355 



dividing line between these classes will be fixed arbitrarily at 5 per 

 cent of lime (CaO) and magnesia (MgO) together, all clays containing 

 over 5 per cent of both oxides being called limey clays, while those 

 carrying less than 5 per cent are termed normal clays. 



TABLE 160. 

 ANALYSES OF NORMAL CLAYS USED IN AMERICAN CEMENT-PLANTS. 



I, 2. Whitecliffs P. C. Co., Whitecliffs, Ark. Trans. Amer. Inst. Mining Engrs., vol. 21. 



3. Santa Cruz, Calif. Mineral Industry, vol. 1, p. 52. 



4. Pacific P. C. Co., Suisun, Calif. C. J. Wheeler, analyst, 



5. " 



6. 



7. 



G! Bedford P. C. Co., Bedford, Ind. A. W. Smith, analyst. 25th Ann. Rep. 'Indiana Dept. 



Geology, p. 328. 



10. Wyandotte P. C. Co., Wyandotte, Mich. 



II. Peerless P. C. Co., Union City, Mich. Lundteigen, analyst. 

 12. Peninsular P. C. Co., Cement City, Mich. 



13. 

 14. 

 15. 



1?! Catskill P. C. Co., Smiths Landing, N. Y. 



18. American Cement Co., Jordan, N. Y. 



19. Iroquois P. C. Co., Caledonia, N. Y. 



20. Hudson P. C. Co., Hudson N. Y. Heiberg and Roney, analysts. 



21. Castalia P. C. Co., Castalia, Ohio. 



22. Omega P. C. Co., Jonesville. Mich. Vol. 8, Mich. Geol. Survey, p. 229. 



23. Almendares P. C. Co., Marinao, Cuba. Engineering Record, vol. 49, p. 37- 



