35 



LEZOtJX (PUY DE DOME). 



Carbonate of lime 72.5 



" magnesia 04.5 



Clay or silex 23.0 



BOLOGNE — POKTLAKD CEMENT, NATURAL. 



Lime 65.13 



Magnesia 00.58 



Silica : 20.42 



Alumina and a small quantity of oxide of iron 13.87 



LONDON — PORTLAND CEMENT, ARTIFICIAL. 



Lime 68.11 



Silica , 20.67 



Alumina 10.43 



Oxide of iron 00.87 



UNITED STATES — ROSEDALE CEMENT, NEW YORK. 



Carbonate of lime 46.00 



Silica, clay and insoluble silicates 27.70 



Carbonate of magnesia 17.76 



Alumina 02.34 



Peroxide of iron 07.26 



Sulphuric acid 00.26 



Chlorides of potassium and sodium ,04.02 



Hygrometric water 00.22 



Loss 00.44 



The Rosedale is an excellent cement, which is used to a 

 considerable extent at Austin, where it is sold at $3 60 per 

 barrel. 



CUMBERLAND CEMENT, ROCK, (MARYLAND.) 



Carbonate of lime 41.80 



Silica clay and insoluble silicates 24.74 



Magnesia 04.10 



Alumina ... 16.74 



Peroxide of iron 06.30 



Soda 04.64 



