Electrosprays in vacuum generate clouds of charged particles moving at high velocities, this talk presents measurements from a new facility to study electrosprays of the heavy ionic liquid EMI-FAP by measuring: mass/charge (m/z), energy E(m/z), and angular distributions of the current density j”(angle) by using multiple concentric annular collector electrodes. Initial observations show that the energies of the various nanodrops and ions of given m/z are all well-defined, but depend notably on m/z, heavy particles having energies well above the potential of emission. In an attempt to rationalize this puzzling behavior, we hypothesize that a fair fraction of the high voltage available at the emitter is used to accelerate the liquid jet as a bulk to a substantial velocity Uj. Beyond this breakup point particles with different m/z are independently accelerated electrostatically in free flight, from the common final jet velocity to their final velocities, naturally resulting in m/z dependent total energies. This two-stage acceleration process explains completely the measured relation between E and m/z, yielding the electrical potential Vj and velocity Uj at the breakup point. Jet velocities as high as 0.6 km/s are measured at the breakup point, consuming up to half of the electrical potential at the emitter.