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TESTS ON CEMENT 



Bunsen burner and is filled with water. The water in the 

 tank is kept at a uniform height by means of a constant-level 

 bottle. A wire screen placed an inch from the bottom of 

 the tank prevents the specimens from coming into contact 

 with the heated bottom. The test pieces, which are 24 hr. 

 old, are placed in the apparatus, which is filled with water of 

 a normal temperature, and heat is applied at a rate such that 

 the water will come to boiling in about ^ hr. Quiet boiling 

 is continued for 3 hr. , after which the specimens are removed 

 and examined. Care must be taken that the water employed 



is clean and fresh, because impure water may seriously 

 affect the results. The same water, also, should never be 

 used for more than one test. A good cement will not be 

 affected by this treatment, and the ball will remain firm and 

 hard. Inferior cement will fail by checking, cracking, or 

 entirely disintegrating. 



The steam test is made in the same way as the boiling test, 

 except that instead of immersing the specimens in water, 

 they are kept in the steam above the water. The apparatus 

 employed is the same as that used for the boiling test. The 



