House and Garden 
THE PANTHEON, ROME. BUILT A. D 120 WALLS OF 
CONCRETE, FACED WITH BRICK 
cement, a great economy of cost is effected at the 
same time that the physical and structural qualities 
of the mortar are improved. The proportion of 
sand to cement varies from three to six according to 
the hardness of the stones or bricks in the wall and 
according to the weight to be imposed upon it. 
EXAMPLE OF ROMAN WALL, INTERIOR OF MORTAR AND 
SMALL STONES, BRICK FACING 
The Portland cements have the further 
invaluable property of not being effected 
by the presence of water after the first 
water is added to the dry powder to form the wet 
mass, or mortar. 1 hat is to say, if we mix the dry 
cement powder with water sufficient to form a paste 
we may place this paste under water and the harden¬ 
ing process will continue as if it were in air, although 
the time of hardening; or setting; will be retarded. 
O O 
Hydraulic 
Properties of 
Portland 
Cement 
A COUNTRY HOUSE IN LOWER CALIFORNIA 
Cement Age. 
Built entirely of concrete, with tile roof. This example illustrates the decorative possibilities of concrete where a plain effect is not desired. 
This is very suitable to the sub-tropical setting of the house 
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