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XXXIV. Ionization by Spraying. By A. S. Eve *. 



SINCE Lenard discovered the presence of negative electri- 

 fication near water-falls, much work has been done and 

 published on the generation of electricity by the splashing of 

 liquids, and by bubbling gases through them. It is not 

 necessary in this paper to refer to these investigations, because 

 an excellent summary of them is given by Professor J. J. 

 Thomson in ' The Conduction of Electricity through Gases/ 

 second edition. The electrical effects due to spraying appear, 

 however, to have received little or no attention f. Last year, 

 whilst making some experiments with an Ebert apparatus for 

 measuring the ionization of the atmosphere, I blew, with an 

 ordinary garden hand-sprayer, very fine mist all round the 

 apparatus. The number of ions detected in the atmosphere 

 was thereby increased by many thousands. Negative ions 

 were in excess of the positive, and their ratio was about 1*4. 

 This crude experiment suggested the use of the small 

 sprayers, made of glass, sold by Beckers, shown in figure 1. 



Fiff. 1. 



J cm 



A steady current of air, filtered through cotton-wool, enters 

 the horizontal conical opening, and draws the liquid up the 

 vertical cone, which has a small hole near its base. With an 

 air-current of about 120 c.c. per second, the liquid drawn up 



* Communicated by the Author. 



t H. A. Wilson used a sprayer to prove his important result — that the 

 amount of electricity which can be transported by substances in the form 

 of vapour equals the amount required to electrolyse the same amount of 

 salt in a solution. Phil. Mag. July 1902. 



