TABLE OF CONTENTS. 



xxni 



PART VII. PUZZOLAN CEMENTS. 

 CHAPTER XLI. 



PUZZOLANIC MATERIALS IN GENERAL. 



PAGE 



Definition of puzzolanic materials 632 



Natural puzzolanic materials 632 



Pozzuolana 633 



Trass 635 



Santorin 635 



Arenes, etc 637 



Range and average composition of natural puzzolanic materials 638 



Natural puzzolanic materials in the United States 638 



Artificial puzzolanic materials 639 



Burnt clay 639 



Blast-furnace slag 639 



CHAPTER XLII. 

 SLAG CEMENT: REQUISITES AND TREATMENT OF THE SLAG. 



Summary of general methods of manufacture 641 



Composition of the slag '. 641 



Requisite chemical composition 641 



Composition of slags actually used 642 



Selection of slags 644 



Granulating the slag 644 



Methods of granulating the slag 645 



Effects of granulating the slag 646 



Increased hydraulicity due to granulation 647 



Desulphurization due to granulation 648 



Drying the slag 649 



Types of dryers used 649 



Rotary dryers 649 



Vertical dryers 652 



CHAPTER XLIII. 

 SLAG CEMENT: LIME, MIXING, AND GRINDING. 



Character and treatment of the lime 653 



Composition of the lime 653 



Burning the lime 654 



Slaking the lime 654 



Sieving and grinding the lime 655 



Mixing and grinding 655 



Proportions of lime and slag 655 



Calculating the mixture 656 



Pulverizing and mixing 657 



