DESIGNING. 219 



resisted by anchorage where the resisting moment is less than 

 the overturning moment. In general it is considered good policy 

 always to provide anchorage, and to design same by considering 

 the weight only of the empty structure, as the maximum wind 

 stress may occur at a time when the water has been withdrawn 

 from the tank. 



The usual anchorage consists of rods with washer and nuts, 

 the former buried in the masonry and the latter screwed down 

 upon the bearing-plate, through which and the capstone the 

 rods project through holes drilled to templet. As has been 

 explained, if the tie at the foot of the tower is omitted, the hori- 

 zontal thrust produced by the weight will be resisted by the shear 

 on the anchor rods, and this must be considered in such cases 

 and the dimensions of the rods fixed accordingly. 



