A new magnetic field configuration in the magnetopause of an open magnetosphere is constructed by superposing a uniform field and the idealized Chapman-Ferraro field. A straightforward interpretation of the results synthesizes previously unrelated models and observations: antiparallel and subsolar merging, uniform-field-plus-dipole models, merging by the tearing mode instability, the magnetic curl configuration in laboratory terella experiments, flux transfer events, and accelerated boundary layer flows.