We have demonstrated trapping, confinement, acceleration, and dumping of electrons in a betatron which has a geometry similar to the Astron. 76±22 nC were accelerated to 800±100 keV. This corresponds to a circulating electron current of 60 A. The betatron has a 6‐cm orbit radius and is 1 m long. Electrons are injected tangentially from a 70‐kV, 15‐A field emission diode. A toroidal field roughly equal to the betatron field is used.