Abstract
To the fog which was produced at the time of adiabatic expansion in the expansion chamber, we applied a near infra-red ray with the wave lengths of 1,307μ, and 1.216μ which have no connection with the absorption band of water vapour. From the ratio of the light transmission for each wave length we estimated the sizes of fog particles. From this we examined the effect of nuclization and the effect by the ultra-violet ray which modified the aforesaid effect of nuclization of AgI, NaC1 and the confined air in the room.
