[Annals N. Y. Acad. Sci., Vol. XXII. pp. 161-224. 10 September, 1912] 



METAMOKPHISM OF POBTLAXD CEMENT 1 



By Albert B. Pacini 



(Read before the Academy, Part I on 8 January, 1912; Part II, 1 April, 



1912) 



COXTENTS 



Part I Page 



Introduction 102 



Xature of the problem 163 



Chemical composition 16-1 



Mineralogical constitution 165 



Setting process 165 



Hardening process 166 



Influence of water upon metamorpbism 168 



Temperature of the water at first added 169 



Temperature of the water that may subsequently come into contact 



with tbe system 171 



Quantity of water at first added 172 



Size of cement particles 172 



Laitance 173 



Hydrolysis theory '. 174 



Mechanical agitation when water is added .' 174. 



Total quantity of water at first added 175 



Quantity of water that may subsequently come into contact with tbe 



system 175 



Surface treatments 177 



Membranes 177 



Mass treatments 177 



Quality of water at first added 178 



Having material in solution 178 



Quality of water that may subsequently come into contact with tbe 



system 180 



Having material in solution 180 



Sea water 180 



Alkali and deep rock waters 181 



Having material in suspension 183 



1 A thesis submitted in candidacy for the degree of Doctor of Science at New York 

 University, 1912. 



Acknowledgments are due to Prof. J. Edmund Woodman and Mr. Raymond B. Earle, 

 of the Department of Geology, New York University, and to Engineer Inspector Ernst 

 Jonson, Board of Water Supply, City of New York, for valuable suggestions made dur- 

 ing the preparation of this paper; also to Mr. Fred H. Parsons. Assistant Engineer, and 

 Messrs. James E. Jay, Charles M. Montgomery and Charles E. Price, Inspectors, of the 

 Board of Water Supply Laboratory, for material assistance during the experimental 

 work. 



(161) 



