A focal plane polarimeter will be constructed for use by the William & Mary College Intermediate Energy Nuclear Physics Group at the MIT/Bates linear accelerator facility. Specifically, the polarimeter will be used in the "100 Spectrometer (OHIPS)" for measurement of recoil proton polarization following electron scattering. Reaction matrix elements corresponding to interference effects will be opened to study for the first time. The first measurement will be a new determination of the magnetic structure function of the proton. This will provide a test of the reaction mechanism through which the neutron charge form factor will be determined. Many other experiments are planned for this new facility.