10 



CEMENTS, LIMES, AND PLASTERS. 



above noted has been taken advantage of in the manufacture of a number 

 of patented artificial stones, the exact methods followed depending 

 upon the particular process that is used. The best known of these 

 artificial stones is probably "Sorel-s tone", which is frequently alluded 

 to in engineering text-books. As the subject of oxy chloride cements 

 is intimately connected with that of magnesia cements, the two will 

 be discussed together in Chapters XI to XII. 



The following table shows the relation of the various cementing 

 materials which have been briefly discussed in this chapter. For con- 

 venience of reference, the pages on which the different products are 

 described in detail have been added. 



Simple cements. . . 



f Plaster of Paris 



Hydrate cements or ! Cement plasters 



plasters | Hard-finish plasters 76-78 



[ Dead-burnt plasters 68-76 



Carbonate cements or 

 limes ............. 



31-67 



j g^^g^ '.'.'. ".} 



1 Magnesia ................. 148-167 



Complex cements . 



f Hydraulic lime ............ 168-193 



G . r I Natural cements ........... 194-293 



Silicate cements ..... j Por tl an d cement .......... 294-631 



I Puzzolan cements ......... 632-689 



Oxychloride cements, j Sorel-stone, etc ............ 162-167 



Chemical and Physical Data Employed in the Discussion of 

 Cementing Materials. 



In the course of the discussion it will frequently be necessary to 

 use certain chemical and physical data, such as atomic weights, values 

 of various heat-units, etc. These are to be found in most engineering 

 pocket-books, but for convenience of reference the more important 

 data have been placed in the present chapter. 



Atomic weights of elements. In the following table (Table 3) are 

 given the names, symbols, and atomic weights of all the chemical ele- 

 ments.* The first column of this table contains the name of each 

 element; the second, its chemical symbol or abbreviation; the third, 

 its atomic weight calculated on the basis of the atomic weight of oxygen 

 being 16; the fourth, its atomic weight on the basis of the atomic weight 

 of hydrogen being 1. 



In use, it is a matter of absolute indifference whether the figures in 



* Through the courtesy of Prof. F. W. Clarke the writer is enabled to present 

 this table, which contains the corrections for 1905. 



