136 



The Philippine Journal of Science 



II show the analyses and the physical tests made on the cements 

 as received. 



Table I. — Chemical analyses of cements as received." 



[Numbers give percentages.] 





Cement— 



A. 



B. 



C. 



D. 



E. 



F. 





2.50 

 0.30 



21.10 

 8.76 

 1.42 



63.10 

 1.26 

 0.67 

 0.93 



2.80 

 0.60 



20.00 

 8.86 

 1.34 



63.00 

 1.34 

 0.86 

 1.16 



1.50 

 0.30 



22.50 

 7.58 

 1.12 



63.00 

 1.74 

 1.34 

 0.87 



2.40 

 0.80 



18.80 

 9.18 

 1.12 



64.10 

 1.12 

 1.34 

 1.16 



2.00 

 0.45 



18.95 

 9.52 

 1.38 



63.80 

 1.80 

 1.24 

 0.87 



22.32 

 8.21 

 3.64 



63.15 

 1.62 



trace 

 1.09 





Silica (Si02) 













.Potassium and sodium oxides (K2O, Na20) 



Most of these analyses were made by Francisco Pefia, inorganic chemist, Bureau of Science. 



Table II. — Physical tests of cements as received. 



Per cent. 

 87.6 



Per cent. 

 99.0 



9 6 



6 40 



7 16 



Tensile strength b — kilograms per square centimeter. 



Neat cement. 



1 day. 7 days. 28 days. 60 days. 



1 day. 7 days. 28 days. 60 days. 



24. S 

 23.6 

 23.2 

 24.5 

 27.3 



41.2 

 44.5 



44.2 



47.8 

 50. 7 

 51.3 



*.:-> 



30.9 

 29.1 



Brand F, without any addition of calcium sulphate, was quick-setting ; consequently no 

 test was made on the original material. 



b Each result is the average of six briquettes. United States Government specifications 

 were followed. 



