CLINKER COOLING, GRINDING, AND STORAGE. 547 



"The experiments quoted indicate that chloride of calcium added 

 in small percentages either to the ground clinker as a powder or mixed 

 with the water for gauging has an important effect in extending the 

 time of setting of Portland cement, and so far as the investigations 

 which are accessible show it does not have any detrimental effect on the 

 permanent strength and hardness. 



"Chloride of calcium is a deliquescent material which rapidly ab- 

 sorbs moisture, and it is possible that if ground dry with the Port- 

 land-cement clinker, even to the amount of per cent, it would cause 

 the material to gather dampness and thus have a bad effect. The 

 chloride of calcium solution can be added readily by adding it to the 

 water used in gauging, since it dissolves with extreme rapidity. The 

 experiments indicate that the set can be controlled by using less than 

 per cent, which would be something less than 2 Ibs. to the barrel of 

 Portland cement. Investigations are still necessary for determining 

 whether the effect of chloride of calcium added to the cement before 

 grinding is permanent in its effects, and whether if ground with the 

 cement clinker it would avert any detrimental effect." 



List of references on use of calcium sulphate, chloride, etc. 



Candlot. Ciments et chaux hydrauliques. 



Carpenter, R. C. Recent experiments with materials which retard the activity 



of Portland cement. Engineering News, vol. 53, pp. 13-14. Jan. 5, 1905. 

 Deval, L. Composition of sulpho-aluminate of lime (in hydraulic cements). 



Bull, de la Soc. d'Encourag. ITnd. National, vol. 5, pp. 49-54. 1900. 



Abstract in Journ. Soc. Chem. Industry, vol. 19, pp. 247-248. 

 Deval, L. Action of sulphate of lime on cements. Bull, de la Soc. d'Encourag. 



ITnd. National, no. 101, p. 784-787. 1901. Abstract in Journ. Soc. 



Chem. Industry, vol. 21, p. 257. 

 Deval, L. Influence of calcium sulphate on cements. Thonindustrie Zeitung, 



vol. 26) p. 913-915. 1902. Abstract in Journ. Soc. Chem. Industry, 



vol. 21, pp. 971-972. 

 Lewis, F. H. Specifications for Portland cements and cement mortars. Proc. 



Engrs Club, Phila., vol. 11, pp. 310-346. 1894. 

 Ljamin, N. Abnormalities in the initial setting of cement. Thonindustrie 



Zeitung, vol. 26, pp. 874-876. 1901. Abstract in Journ. Soc. Chem. 



Industry vol. pp. 972-973. 

 Nihoul, E., and Dufossez, P. Note on the retardation of setting of Portland 



cement. Bull. Scient. de 1'Assoc. des Eleves des Ecoles speciales de 



Liege, no. 3. Abstract in Journ. Soc. Chem. Industry, vol. 21, pp. 859- 



860. 

 Rohland, P. Hydration of Portland cement. Zeits. angew. Chemie, vol. 16, 



pp. 1049-1055. 1903. Abstract in Journ. Soc. Chem. Industry, vol. 22, 



pp. 1244-1245. 



