Observations of cosmic radio‐frequency radiation on frequencies of 2130 kc/sec, 1435 kc/sec, 900 kc/sec, and 520 kc/sec have been made, using a method of recording which effectively reduces interference from atmospherics. At these frequencies, the intensity of the radiation is approximately 10−19watt per square metre per cycle per second per steradian. The ionospheric effects associated with observations near the critical frequency are discus