PROPERTIES OF PORTLAND CEMENT. 

 versus free lime — Continued. 



395 



Interpretation of microscopic test. 



Result of soundness tests. 



Condition and amount 

 of free lime. 



Soundness. 



In steam. 



In air. 



In water. 



In steam. 



In air. 



In water. 



No free lime 



Sound 



do—. 



do ... 



Sound 



do____ 



do 



Sound 



do___. 



do 



Sound 



Small radi- 

 al cracks. 

 Hard, but 

 warped 

 scinch. 



Sound 



do. 



do 



Sound. 

 Do. 



Do. 



A little sintered lime 

 and a little slaked 

 lime. (A well- 

 burned or a well- 

 seasoned cement.) 



Only a trace of slaked 

 lime. (A very well- 

 burned or a very 

 well-seasoned c e - 

 ment.) 













