Abstract
The observations of colour of the sky have been carried out since April 1930 at the Central Meteorological Observatory and also since May 1931 at the Utunomiya Meteorological Station by means of the “Ostwald-Linkesche Himmelsfarbenskala” (Met, Zeit. Bd. 45, S. 367, 1928). According to the statistics of observations it appears that in both places the colour of the sky is bluer in autumn and winter than that of the spring and summer. As to the daily change, the sky is bluer in the afternoon than in the morning in Tokyo, but at Utunomiya the daily change is not conspicuous. In the mean, the colour at Utunomiya is about 1.4 degree bluer than that of Tokyo.
