384 Mr. A. S. Eve 



on 



natural leak o£ the electroscope, about 0'4 microscope 

 division a minute, was not affected by a strong air-cnrrent 

 through it. 



(2) That the spray from liquids did not destroy, or impair, 

 the insulation of the gold-leaf system and central cylinder. 



(3) That a large number of ions, both positive and negative, 

 were generated by spraying, and the total electricity con- 

 veyed by either could be measured by the electroscope. 



(4) That about 50 per cent, of the ions from water spray 

 were present after passing along 13 metres of glass tubing 

 (6 mms. in diameter) before entering the electroscope ; or 

 along 3 metres of tubing 2 cms. in diameter. 



(5) That the ions were entirely removed by a cotton-wool 

 filter, placed between the sprayer and the electroscope. 



(6) That under the conditions of the experiments, not more 

 than 5 per cent, (and generally less) of the ions passed from 

 the testing chamber of the electroscope, if charged, into a 

 second instrument similar to the first. 



(7) That distilled water always gave rise to more ions than 

 tap water taken from the city supply pumped from the River 

 St. Lawrence. 



(8) That distilled water and tap water always gave more 

 negative than positive ions, the ratio being from 1*2 to 1*6. 

 The same result was found for ether. 



(9) In the case of spray from substances such as chloro- 

 form, amyl, ethyl, benzyl, methyl alcohols, methyl iodide, 

 acetic acid, acetone, aldehyde, and amyl acetate, the number 

 of positive and negative ions were equal for each substance. 

 These substances gave about twice to four times as many ions 

 as distilled water, the conditions being identical. 



(10) The addition to water of salts, such as caustic soda, 

 sodium chloride, sea salt, sodium carbonate, or of acids such 

 as hydrochloric or sulphuric, reduced the number of ions to 

 lower values than for water alone. 



(11) That liquids such as benzine, rhigoline, phenetol, 

 cineol, toluene, turpentine, even the most volatile, gave but 

 few ions, compared with water. 



(12) Mercury gave no effect that could be detected under 

 the conditions of the experiments. 



Some of these results for spray might have been predicted 

 from the work of Lenard, Kelvin, J. J. Thomson, and others, 

 in their investigations of the splashing of liquids or the 

 bubbling of air through them. Some of the above obser- 

 vations, such as 9 and 11, appear to be new. 



In figures 3 and 4 are given a few of the numerous curves 

 obtained for various liquids when the air-current ran for a 



