Abstract
The number of smoke particles and the shade number of air filter were observed at the Oosaka Branch Observatory of the Central Meteorological Observatory at the same time from Jan. 1 to Dec. 31, 1938. Though these two values mainly express the concentration of smoke particles, there are found many interecting relations when observed in detail.
(1) There is on close correlation between the smoke particles and the shade number of air filter, but the coefficient is positive.
(2) This coefficient is maximum at 8 o'clock and minimum at 20 o'clock and[Rs, b]8h>[Rs, b]12h>[Rs, b]16k>[Rs, b]20h>0 as shown in Fig. 1.
(3) The observed values are shown in the Fig. 2, and the points in this figure are distributed somewhat widely.
(4) There are almost no observation in the range of smoke particles from 0 to 50 particles per c. c., but 0-shade of air filter was observed frequently.
(5) The results are shown in the figure 2.
(6) As I have stated above, there are many particles whose colour is not black, and there are diurnal variation of double maxima and minima for the number of these particles in the atmosphere.
(7) The rate of the increase of the number of the smoke particles for the 1 difference of the shade number of air filter is maximum at 8 o'clock, and minimum at 20 o'clock.
