218 



REIBLING AND REYES. 



The silica, aluniina and iron oxide from the fuel may or may not have combined 

 with the ealcixim oxide in the raw meal, and therefore consideration of this fact 

 is given by formulas of columns 9 and 10. The possibility of magnesia acting 

 as lime and iron oxide as alumina has also been included in the diagnosis of 

 these cements. 



We also were unable to obtain more definite information as to the 

 probable setting qualities by taking into consideration the nature of 

 the raw materials used or the burning processes employed. Our knowl- 

 edge in this respect is somewhat limited, but the evidence given in 

 Table XXII is sufficient to justify the conclusion that if we consider 

 the setting properties of Portland cements, there is no characteristic 

 belonging to them which necessarily would indicate that the cement 

 had been manufactured by any certain process of burning or from any 

 definite class of raw materials. 



Table XXII. — Changes in physical properties produced by thoroughly aerating 

 standard Portland cements. 



Description. 



a 60 si 



as. 



O C 



(S 03 — 

 > 



dP..2 



St ^ *3 



P ci c 

 »^ t- O 

 o o o 



c'o'3 



Setting time. 



Initial 

 set. 



Final 

 set. 



Cements made from hard mountain limestone and clay by the set-kiln process. 



Brand "X." 



Fineness=8S.8 and 97.3 per cent. 

 Loss bv ignition=2.70 per cent. 

 Per cent of S03=2.16. 



Coal was burned in direct con- 

 tact with the raw-meal bricks. 

 Clinkering temperature produced 

 bv direct combustion of coal. 



25.5-29.0 







3.06 



20.0 



1 



10 



25. 5-27. 5 



3 



3.045 



21.8 



3 







26. 0-30. 5 



7 



2.99 



22.0 



1 



30 



25. 2-27. 



28 



2.97 



24.5 







40 



26. 0-28. 5 



60 



2.92 



28.0 



1 



15 



26.0-28.5 



270 



2.807 



39.0 



105 



X 



26.5-30.0 







3.12 



21.0 



2 



30 



26.5-30.0 



3 



3.10 



19.5 



2 







25. 0-29. 



7 



3.08 



20.0 



3 







26. 0-30. 



14 



3.07 



21.0 



2 







26. 0-28. 



28 



3.04 



22.0 







8 



25. 5-30. 



30 



3.04 



22.0 







15 



26. 0-30. 



60 



2.99 



23.0 



2 



30 



26.0-30.0 



90 



2.90 



24.0 



3 



10 



26. 0-28. 5 



270 



2.857 



30.0 



7 



X 



2 

 6 

 6 

 1 

 2 

 552 



Brand "L." 



Fineness=75.0 and 93.0 per cent. 

 Loss bv ignition=2.52 per cent. 

 Per cent of SO3=0.60. 



Coal was ground to pea size 

 thoroughly mixed with raw-meal 

 and the whole compressed into 

 bricks. Clinkering temperature 

 produced by the combustion of 

 carbon monoxide. 



7 

 6 

 5 

 6 

 6 

 6 

 .7 



8-f 

 144 





 10 

 30 

 20 





 30 





 X 

 X 



Cement made from hard mountain limestone and clay by the rotary process. 



Brand "G." 



Fineness=79.2 and 93.0 per cent. 

 Loss by ignition=2.10 per cent. 

 Per cent of 803=1.37. 



26-28. 







3.10 



19.0 



2 







6 



26-30. 



15 



3.08 



21.0 



1 



30 



4 



27-30.0 



35 



3.06 



21.0 



2 







5 



27-30. 



50 



3.048 



22.0 



2 



30 



5 



27-28. 5 



60 



3.046 



22.5 



2 



20 



5 



27-28. 



90 



2.99 



24.0 



3 



10 



8- 



20 

 30 

 30 

 

 

 X 



