  The insulating state of magnetite (Fe$_{3}$O$_{4}$) can be disrupted by a
sufficiently large dc electric field. Pulsed measurements are used to examine
the kinetics of this transition. Histograms of the switching voltage show a
transition width that broadens as temperature is decreased, consistent with
trends seen in other systems involving "unpinning" in the presence of disorder.
The switching distributions are also modified by an external magnetic field on
a scale comparable to that required to reorient the magnetization.
