APPLICATION OF GRAPHIC METHODS 



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that of 3 and 4 ; this last link will be in equilibrium under the 

 action of the forces acting on b, as shown in the half links. In 

 a more complicated example the link 2 might be replaced by a 



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complete frame, or by a rigid plate. Since the forces acting on 

 one element either intersect at one point or in a series of points 

 which may be joined by other links, we may always designate 

 the point or points in question by the same letter of the 



