We calculate the force on part of a single closed circuit due to the r
emaining circuit in four different geometries according to the forces
of Ampere and Grassmann. All analytical calculations are performed usi
ng surface or volume current elements in order to avoid the divergence
s which appear with linear current elements of zero diameter. We concl
ude that when we consider the action of a closed circuit as a whole an
d utilize only circuits with closed Lines of current, there will be an
equivalence between the expressions of Grassmann and Ampere. This mea
ns that both of them are compatible with the experimental findings rel
ated to Ampere's bridge, contrary to the opinion of some authors.