10 CONTENTS. 
Part III. Natural Cement Resources of the United States. 
Page. 
Introduction 333 
Definition 333 
Relations of natural cements to other cements 334 
Raw material (natural-cement rock) 334 
Methods of manufacture 335 
Georgia 336 
Illinois • 339 
Indiana-Kentucky 341 
Kansas 342 
Maryland- West Virginia 343 
Minnesota 344 
New York 345 
Rosendale district 345 
Howes Cave 347 
Central New York 348 
Akron-Buffalo district 349 
North Dakota 351 
Ohio 352 
Pennsylvania 353 
Texas 354 
Virginia 354 
West Virginia and Maryland 354 
Wisconsin 354 
References on natural cements 355 
Part IV. Materials and Manufacture of Puzzolan Cements. 
Puzzolanic materials 357 
Natural puzzolanic materials ( pozzuolana, trass, etc. ) 357 
Artificial puzzolanic materials (blast-furnace slag) 359 
The manufacture of slag cement 359 
Composition of the slag 359 
Granulating the slag 362 
Drying the slag 363 
Composition and selection of the lime 365 
Drying and slaking the lime 366 
Sieving and grinding the lime 366 
Mixing and grinding the slag and lime 367 
Composition and properties of slag cement 369 
Identification of slag cement 370 
Plants, prices, and uses 371 
Index 373 
