206 



CEMENTS, LIMES, AND PLASTERS. 



TABLE 91. 

 ANALYSES OF NATURAL-CEMENT ROCKS, CUMBERLAND AND HANCOCK, MARYLAND. 



Data insufficient for averaging. 



1. Hancock, Md. C. Richardson, 



2. Cumberland, Md. E. C, ~ 



Mortars", p. 125. 



wdson, analyst. Brickbuilder, vol. 6, p. 151. .July, 1897. 

 . Boynton, analyst. Quoted by Gillmore, "Limes, Cements, 



and 



3. Hancock, Md. C. Huse, analyst. Quoted by Gillmore, "Limes, Cements, and Mortars' 



p. 125. 



4. Cumberland, Md. C. Richardson, analyst. Brickbuilder, vol. 6, p. 151. July, 1897. 



5. Average of preceding four analyses. 



TABLE 92. 

 ANALYSES OF NATURAL-CEMENT ROCK, MANKATO, MINN. 



1. C. F. Sidener, analyst, llth Ann. Rept. Minn. Geol. Surv., p. 179. 

 2-6. Clifford Richardson, analyst. Cement Directory, p. 206. 



The second plant is said to be located at Austin, Mower Co. If this 

 location be correct, the limestone used is probably of Devonian age. 



ANALYSIS OF NATURAL-CEMENT ROCK, AUSTIN, MINN. 



Silica (Si0 2 ) ^ 



Alumina (A1 2 O 3 ) / 15>5y 



Iron oxide (Fe 2 O 3 ) 2.09 



Lime (CaO) 27. 55 



Magnesia (MgO) 13.80 



Sulphur trioxide (SO 3 ) .06 



Carbon dioxide (CO 2 ) 36.84 



