ARTIFICIAL STONE, OR CONCRETE 



else being equal, each angle requires a different 

 amount of metal, differently placed, to secure the 

 same resistance; but this is an engineering problem 

 too complicated to be considered here at length. 



As the metal work is all completely buried in the 

 cement in the finished structure, there is no way of deter- 

 mining by casual observation what form of reinforce- 

 ment may have been used in any particular building. 

 The exposed surfaces appear the same whether the 

 reinforcement is a network of fine wires, or heavy 

 "I" beams, and if properly constructed there is no 

 difference in strength and durability. Some idea of how 

 certain forms of reinforcement would look if concrete 

 were transparent may be had from the appearance of 

 "wire-glass," " reinforced glass" it could be called 

 appropriately which has become so popular in recent 

 years. In this the mesh of wire can be seen embedded 

 in the glass, the percentage of space occupied by the 

 wire as compared with the amount of glass being very 

 small. This same kind of reinforcement is used ex- 

 tensively in certain kinds of reinforced-concrete con- 

 struction, but the size of the wire, and the resulting 

 meshes are larger, although the proportions are not 

 unlike those in wire-glass. 



A MODERN BUILDING 



Since there are so many different ways of using the 

 reinforcement in concrete construction, perhaps a bet- 

 ter way to gain a fairly clear idea of the subject, the 

 size of the metal rods used, and the actual process of 



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