TABLE OF CONTENTS. vii 



PAGE 



Use of accelerators 66 



Hardening gypsum and plaster 67 



References on properties and tests of plasters 67 



CHAPTER IV. 



FLOORING-PLASTERS AND HARD-FINISH PLASTERS. 



Characters of the two groups 68 



Flooring-plasters 68 



Composition of flooring-plaster 68 



Van't Hoff s investigations 69 



Composition and structure of flooring-plaster 69 



Change of volume on hardening 70 



Increase of weight on hardening 73 



Methods of manufacture 75 



Uses of flooring-plasters 75 



Hard-finish plasters 76 



Definition 76 



Keene's cement . . . . , 76 



Manufacture 76 



Composition 77 



Properties 78 



Mack's cement 78 



References on dead-burned and hard-finish plasters 78 



CHAPTER V. 



STATISTICS OF THE GYPSUM AND PLASTER INDUSTRIES. 



Total use of gypsum in the United States, 1900-1903 79 



Distribution of total by uses, 1900-1903 79 



Production in the United States, by uses, 1890-1903 80 



Production in the United States, by States and classes of product, 1902-1903 81 



Production by States, 1890-1901 83 



Imports of gypsum and plaster, 1900-1903 84 



World's production of gypsum, 1893-1903 86 



PART II. LIMES. 

 CHAPTER VI. 



COMPOSITION, ORIGIN, AND GENERAL CHARACTERS OF LIMESTONES. 



Origin of limestones 88 



Varieties of limestone 89 



Chemical composition of limestone 89 



Presence of magnesia 90 



Presence of silica, alumina, iron, and other impurities. 91 



