  In this paper, it is emphasized that the dynamical cause for the A-B effect
is the superimposed energy between the magnetic field produced by the moving
charges and that in the solenoid, instead of the existence of the vector
potential. If such a superposition between the magnetic fields can be
eliminated, the A-B effect should not be observed any more. To verify this
viewpoint, a new experimental method using a SQUID is suggested in this paper.
