In reply to a question by Mr. Unwin, Dr. Bowen stated that there 

 were no obvious reasons for the few unsuccessful cases that had occurred 

 in his experiments ; in fact, the appearance of the cloud in the successful 

 cases had not differed materially from the cloud in the unsuccessful 

 tests. In reply to another question he said that there was a possibility of 

 seeding the cumulus type of cloud from below by making use of the 

 up-currents that are always present in these clouds. He believed the 

 experiment had been tried, but this method was not used in Australia. 



THE BEHAVIOUR OF WATER IN ITS VARIOUS PHASES AT 



LOW TEMPERATURES AND ITS APPLICATION 



TO METEOROLOGY 



[Abstract] 



By B. M. CwiLONG, Victoria University College 



This paper describes in some detail a series of experiments on the 

 properties of water, particularly with regard to phenomena of condensa- 

 tion. Various different characteristics possessed by certain metallic 

 surfaces and their effects on the condensation of water vapour are 

 discussed. The properties of silver iodide are also discussed, and some 

 insight is given into the effectiveness of these nuclei in the seeding of 

 clouds for the production of rain. 



A FORM OF POTENTIAL GRADIENT SONDE APPARATUS 

 By K. Kreielsheimer, Auckland University College 



[Abstract] 



The method of modifying the Bureau of Standards' Radio-Meteoro- 

 graph for the measurement of the potential gradient in the atmosphere 

 is explained. The method is based on the current due to point-discharge 

 under the influence of the electrostatic field surrounding the earth. 



Various demonstrations are given to show the effect and the 

 extensions required to the method to record both small and large gradients 

 with sufficient accuracy. The calibration of the sonde and the factors 

 affecting the measurements are discussed in detail. 



The research is concerned particularly with the disturbed conditions 

 due to thunderclouds and the charge distribution within these clouds. 



ON THE SEGREGATION OF THE SEA-SALT COMPONENTS AND 

 THEIR DISTRIBUTION IN THE AIR 



By Ken Sugawara, Shinya Oana, and Tadashiro Koyama, 

 Nagoya University, Japan 



[Abstract{^)] 



It was shown that the chemical composition of the wind-borne salt 

 from sea varies so that Ca/Cl and SO4/CI increase horizontally, as it 

 recedes from sea beach towards inland, and also vertically, as we go 

 from sea-level upwards. The horizontal variation was proved in two 

 different ways — the one, by the comparision of the chemical analyses 

 of more than one hundred rain samples from three different stations, 

 differing in distance from sea, and the other, by that of the salt which 



(1) A fuller account will be published in Bulletin of the Chemical Society of 

 Japan, Vol. 22, No. 2. 



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