  Using the graphical method developed in hep-th/9908082, we obtain the full
curve corresponding to the hyperk\"ahler quotient from the extended E_7 Dynkin
diagram. As in the E_6 case discussed in the same paper above, the resulting
curve is the same as the one obtained by Minahan and Nemeschansky. Our results
seem to indicate that it is possible to define a generalized Coulomb branch
such that four dimensional mirror symmetry would act by interchanging the
generalized Coulomb branch with the Higgs branch of the dual theory. To
understand these phenomena, we discuss mirror symmetry and F-theory
compactifications probed by D3 branes.
