Some Long-Distance Transmission Phenomena of Low-Frequency Waves

From the results of a series of twenty-four-hour receiving measurements conducted here for more than two and a half years, some interesting phenomena are picked out and discussed. The main points of the conclusions reached are: (1) the daylight signal strength of Kahuku is greater than the night signal strength; (2) several successive crevasses of about a two hours´ period are observed regularly in the signal strengths of Bolinas and Kahuku during the partial daylight hours.