Experiments and Observations concerning the Ionized Regions of the Atmosphere

Experiments are described in which a virtual height of the reflecting ionized region was measured using time lag between impulses arriving over a direct, and the reflected path. The measurements were made on 57 and 111 meters. The height was ascertained only at night and the daylight hour before sunset. Movements of the reflecting region are plotted showing slow rises and rapid drops. The rising rate approximates 6 miles a minute, and the falling rate about 20 miles a minute. Multiple reflections were observed. Transmission measurement curves are given showing dependence of 16-7/8 meter signals on the night ionization, and the assistance that sunlight ionization can give. Experiments and curves are mentioned that show absorption to be one of the important factors causing poor daylight transmission in the wavelength region contiguous to 214 meters. It is pointed out that the absorbing region is below the refracting region and that the sky wave must make two passages through the absorbing region. A discussion is given to show that both electromagnetic waves from the sun, and β particles, must be assumed as producers of ionization to explain phenomena observed. By this theory the electromagnetic waves from the sun produce the ionization in the absorbing region, and part of the day ionization in the refracting region. This ionization is pictured as beginning at an altitude of about 16 miles and extending upward, and as experiencing diurnal and seasonal variations.