about thirty scientists at Nemuro, in the eastern, end of Hokkaido. In 

 these investigations balloon observation in fog and photographing of 

 fog advection by means of slow-speed cine-camera were especially the 

 effective means of investigation. In the second year, the experiment 

 on " fog dissipation car," as a concrete method of the artificial dissipation 

 of fog, was carried out at Tomakomai, in the southern coast of Hokkaido. 

 Further, parallel with this experiment, preliminary tests on the method 

 of measuring fog and on the artificial dissipation of fog were carried out 

 at Kirigamine (1,925 m.), Nagano Prefecture and Nisekoan'nupuri 

 .(1,300 m.), Hokkaido. 



The results of these investigations are summarized as follows : — - 



Part I — Investigations on the Method of Measurements of 



Fog 



1. H. Ogiichi : Method of Measurement of the Dimension and Number 



of Fog Particles 



Detailed investigations and discussions were carried out on the 

 apparatus and its error measuring the dimension and number of fog 

 particles by means of microscopic photographing of fog particles captured 

 on oil membrane made on glass plate. 



2. /. Sugaya : Correction of Distribution Curve of Diameters of Fog 



■ Particles by Means of the Rate of Capture 



Noticing the difference of the rate of capture due to the dimension 

 of fog particles in case of capturing them on glass plate, the method to 

 correct the distribution curve of diameters of fog particles was discussed. 



3. M. Hanashima : Measurement of Total Amounts of Waters Contained 



in the Atmosphere 



A special apparatus was devised in order to capture, simply and 

 with high accuracy even in open air, the total amounts of waters 

 contained in the air of 20 litres passed through a small glass tube 

 filled with mixture of glass cotton and phosphorous pentoxide. 



4. K. F-ukutomi, H. Kusunoke, and C. Tabata : Meas^irement of the 



Amount of Fog Waters by Means of Meshes of Net 



An apparatus was devised in order to measure the amount of fog 

 waters by capturing fog particles in the air with some gauzes or metal 

 nets laid upon another. By means of this apparatus the dimension 

 of the most frequent radius of fog particles can be known besides the 

 amounts of fog waters. 



■5. K. Ftikutomi and Y. Matsumura : Rate of Capture of Fog Particles 

 by Metal Net 



The experiments show how fog particles are captured in case of the 

 passing of fog through metal nets. Particles are captured only when 

 their centres hit the wires of metal nets. 



6. K. Fukutomi and C. Tabata : Trial Manufacture of Self-recorder of 

 Amount of Fog Waters 



The continuous recording of the amounts of fog waters was made 

 with pluviograph by leading fog particles captured by metal nets to it, 

 and at the same time the wind velocity was self-recorded. By using 

 both records the fluctuation of the amounts of fog waters in unit volume 

 air was studied. 



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