PACINI, METAMORPHISM OF PORTLAND CEMENT 



215 



Table 24 

 Analyses of the Cements Used in Tests with Saline Solutions 





Per cent 



A 



B 



c 



Si0 2 



23.50 

 2.36 

 7.28 



62 18 

 2.29 

 1.11 

 1.28 



19.74 



2.75 

 8.77 

 60.86 

 2.86 

 1.39 

 3.63 



22.99 

 2.42 

 6.79 



60.84 

 4.14 

 1.76 

 1.06 



Fe,0 3 



A1 2 3 



CaO 



MgO 



S0 3 



C0 2 H 2 0, alkalies 



The cubes were stored 24 hours in the damp closet, and then trans- 

 ferred to the solutions mentioned in the following table, three cubes to 

 each liquid, and there stored for three months, then broken. 



- , ■* 

 Table 25 



Compressive Strength of Mortars Stored for Three Months in Various Saline 



Solutions 



(Each value is the average of three determinations) 



Storage medium 



Pounds per square inch 



High 

 silica 



Gain, 

 per 

 cent 



Low 



silica 



Gain, 

 per 

 cent 



Finely 

 ground 



Gain, 

 per 

 cent 



Coarsely 

 ground 



Gain, 

 per 



cent 



Croton water. . . 



Sodium 5% 

 sulphate, 10% 



Magnesium 5% 

 sulphate, 10% 



Sodium 5% 

 chloride, 10% 



Magnesium 5% 

 chloride, 10% 



Calcium 5 % 

 chloride, 10% 



Average gain 

 (per cent) 



2217 



2267 

 3264 



3244 



2604 



2365 



1778 



2331 

 1757 



2653 

 2224 



2 

 47 



46 



18 



7 

 -20 



5 

 -21 



19 

 



2462 



2090 

 2035 



1787 

 2646 



1785 

 2019 



1827 

 1769 



2516 9 

 1994 



-15 

 -18 



-28 



7 



-28 

 -18 



-26 



-28 



2 

 -19 



2134 



3266 

 2223 



2233 

 3003 



2305 



2968 



2731 

 2570 



2219 

 2042 



53 

 4 



5 



42 



8 

 40 



33 

 20 



4 

 -4 



2066 



2273 

 2262 



2759 

 2489 



2695 

 2044 



2305 

 2269 



1808 

 2238 



10 

 9 



33 

 20 



30 

 -1 



12 

 10 



-13 



8 



10 



-17 



20 



12 



Average of two determinations. 



