ILLUSTRATIONS. 



TEXT FIGURES. 



Fig. 1. Sealed tubes showing the effect of water on the formation of calcium 

 hydroxide-phenol crystals. 



2. Characteristic crystals obtained by the microscopic test from calcium 



hydroxide. 



3. Characteristic crystals obtained by the microscopic test from calcium 



oxide. 



4. Crystalline calcium hydroxide obtained from sintered lime. 



5. Characteristic crystals obtained by the microscopic test from calcium 



oxide ignited at a red heat. 



6. Characteristic crystals obtained by the microscopic test from nonsintered 



lime in Portland cement. 



7. Characteristic plume-like formations of crystals obtained from sintered 



lime. 



8. Characteristic plume-like formations of crystals obtained from sintered 



lime in Portland cement. 



9. Characteristic crystals obtained from slaked lime in Portland cement. 



10. Characteristic plume-like formations of crystals obtained from coarse 



particles of sintered lime in nonseasoned, hard-burned Portland cement. 



11. Characteristic rosettes of long, slender crystals obtained from the coarse 



particles of sintered lime in hard-burned cement after they had reached 

 the final stage in the process of hydration by aeration. 



12. Diagram showing the characteristic effects of thorough aeration on the 



different volatile constituents of Portland cement. 



13. Diagram showing variations in the effects of thorough aeration on the 



volatile constituents of Portland cement. 



14. Photograph of commercial Portland cement clinkers showing particles of 



free lime visible to the naked eye. 



1. Stationary kiln clinker (brand L). 



2. Stationary kiln clinker ( brand ) . 



3. Rotary kiln clinker (brand 0). 



4. Rotary kiln clinker (brand K). 



15. Photograph of sound and disintegrated commercial Portland cement 



clinkers. 



1. Characteristic sound, weathered, stationary kiln clinker split open 



to show its homogeneous and perfectly sintered condition. 



2. Piece of raw-meal brick which had almost escaped the fire. The 



particles of ground limestone were held together by the cohesion 

 of the dehydrated, compressed clay. This shows one possible 

 source of the carbon-dioxide in commercial cements. 



3. Characteristic disintegrated product of weathered, underburned, 



stationary kiln clinker. 



417 



