xxxii LIST OF TABLES. 



131. Compressive tests of natural cements 274 



132. " strength of 4-inch natural-cement cubes 275 



133. Effect of heating on compressive strength 275 



134. Relation of tensile to compressive strength of natural-cement 276 



135. " tt u tt " Utica natural cement 276 



136. Modulus of elasticity 277 



137. Fineness required by various specifications 282 



138. Strength " " " " 283 



139. Cement supplied to N. Y. Rapid-transit subway, 1900-1901 283 



140. Summary of natural-cement tests, 1897-1900 284 



141. Dates of establishment of natural-cement industries in various States. . . . 288 



142. Production of natural cement in 1901, 1902, and 1903, by States 290 



143. Total production of various cements in U. S., 1818-1904 291 



144. Character of Portland-cement materials 301 



145. Production of Portland cement from various materials 304 



146. Analyses of hard limestones used in American cement-plants 314 



147. " "purechalks " " " " " 321 



148. " "clayey " " " " " " 321 



149. " " Hudson shale and slate in Pa. and N. J 325 



150. " " Trenton limestones 326 



151. " " Kittatinny magnesian limestone. . 327 



152. " " "cement-rock" 329 



153. " " pure limestone used for mixing with cement rock 329 



154. Portland-cement production of the Lehigh district, 1890-1902 332 



155. Analyses of "cement-rock" materials from the Western U. S 333 



156. Fineness of crude marl 340 



157. Analyses of marls used in American cement-plants 342 



158. ' ' " alkali waste, ammonia process 349 



159. " " iron-furnace slags 351 



160. " " normal clays used in American cement-plants 355 



161. " "limey " " " " " " 356 



162. " " normal shales " " " " " 357 



163. " "limey " " " " " " 359 



164. " " American roofing slates 364 



165. Composition of American roofing slates 364 



166. Analyses of slate used for Portland cement, Rockmart, Ga 365 



167. Detailed costs of steam-shovel work 373 



168. Effect of alumina 388 



169. Analyses of raw materials containing phosphoric acid 390 



170. Tests of cements containing phosphoric acid 390 



171. Composition of actual mixes 394 



172. Analyses of fuel ash 396 



173. Change in composition during burning. 397 



174. Cement mixture and cement, Sandusky 397 



175. Fineness of raw mix at various plants 425 



176. Sizes, power, etc., of Gates crushers 433 



177. Estimated cost of crushing by Gates crusher 433 



178. Sizes, power, etc., of Griffin mill 442 



