Report on Ionization Changes during a Solar Eclipse

The effect of a solar eclipse upon air layers ionized by different solar agencies is described, and the observations of the actual eclipse changes in ionized layers are considered. The conclusion is reached that the normal ionizing agency for regions E and F
1
, has a speed closely agreeing with that of light; hence it is natural to identify this agency with ultra-violet light (though observations of the kind here considered cannot rule out the possibility that the agency, for one or more of these layers, consists of very high speed corpuscles). Similarly there is fairly definite evidence that ultra-violet light contributes at least a part of the normal region F
2
ionization, and a suggestion that corpuscles may also contribute. In future eclipses it is very desirable that attention should be specially concentrated on this region F
2
.