This paper describes measurements which have been made on the coincidence counting rate between the fissions produced in an ionization chamber and the discharges of a Geiger counter. By determining the absolute efficiency of the counter, the total energy emitted in the form of γ-radiation was estimated to be about 4.6 ± 1.0 Mev. Measurements have been made on the range of the electrons projected from an aluminum radiator placed between the ionization chamber and two thin-walled counters. From this experiment, the average energy of the radiation appears to be about 2.5 Mev. The result is confirmed by absorption measurements in lead. The absorption curve indicates a fairly homogeneous radiation and gives some evidence for the existence of a softer component with an energy of about 500 kev.