PREPARING THE MIXTURE FOR THE KILN. 411 



Meade, R. K. The plant of the Northampton Portland Cement Co., Pa. En- 

 gineering Record, vol. 48, pp. 182, 183. Dec. 5, 1903. 



Meyer, H. C. New works of the Coplay Cement Co., Coplay, Pa. Engineering 

 Record, Feb. 27, 1900. Cement Industry, pp. 69-77. 1900. 



Meyer, H. C. The works of the Nazareth Portland Cement Co., Nazareth, 

 Pa. Engineering Record, Dec. 16, 1899. Cement Industry, pp. 85-95, 

 1900. 



Meyer, H. C. The Whitehall Portland Cement Works, Cementon, Pa. En- 

 gineering Record, Sept. 15, 1900. Cement Industry, pp. 142-150. 1900. 



Stanger, W. H., and Blount, B. [The Atlas Portland- cement plant, Pa.] 

 Proc. Inst. Civil Engineers, vol. 145, pp. 57-68. 



Vredenburgh, W. The Virginia Portland Cement Co. 's Works, Craigsville, Va. 

 Engineering Record, July 28, 1900. Cement Industry, pp. 132-141. 1900. 



Anon. The Almendares Portland Cement Works, Cuba. Engineering Record, 

 vol. 49, pp. 36-38. Jan. 9, 1904. 



Anon. Edison Portland Cement Company [N. J.]. Iron Age, Dec. 24, 1903. 



Anon. The works of the Edison Portland Cement Co., near Stewartsville, 

 N. J. Engineering Record, vol. 48, pp. 796-802. Dec. 26, 1903. 



Anon. The Edison Portland Cement Works at New Village, N. J. Engineer- 

 ing News, vol. 50, pp. 555-559. 1903. 



Anon. Alsen's American Portland Cement Works, N. Y. Engineering Record, 

 vol. 47, pp. 10-13. Jan. 3, 1903. 



Anon. Plant of the Hudson Portland Cement Co,, at Hudson, N. Y. En- 

 gineering News, vol. 50, pp. 70-71. July 23, 1903. 



(2) Methods Used with Slag-Limestone Mixtures. 



While the manufacture of Portland cement from a mixture of 

 slag and limestone is similar in general theory and practice to its manu- 

 facture from a limestone-clay or other dry raw materials, certain inter- 

 esting differences occur in the preparation of the mixture. In the 

 following paragraphs the general methods of preparing mixtures of 

 slag and limestone for use in Portland-cement manufacture will first 

 be noted, after which certain processes peculiar to the use of this par- 

 ticular mixture will be described separately. 



General methods. After it had been determined that the puzzo- 

 lan cement made * by mixing slag with lime without subsequent 

 burning of the mixture was not an entirely satisfactory structural 

 material, attention was soon directed toward the problem of making a 

 true Portland cement from such slag. The blast-furnace slags com- 

 monly available, while carrying enough silica and alumina for a cement 

 mixture, are too low in lime to be suitable for Portland cement. Addi- 



*See Part VII. 



