76 



ME. GEOKGE C. SIMPSON ON THE 



TABLE IX. lonization and Dissipation according to Wind. 



We see that, allowing a large margin for the uncertainties of such an investigation, 

 the dissipation may be regarded as a linear function of the ionization for any given 

 wind strength. It must be remembered that this agreement is only true when 

 dealing with a large number of observations ; for the mobility of the ions affects the 

 dissipation considerably. It would be interesting to compare individual observations 

 of the ionization and the dissipation when the wind strength was accurately known. 

 In that case the effect of the mobility of the ions would be very apparent. My 

 observations do not allow of this being done, as the wind strengths were only roughly 

 judged by the " feel " of the wind, and no doubt varied very much more amongst 

 themselves than the mobility did. For the same reason it is of no use finding from 

 my observations how the dissipation varied with the wind strength, the ionization 

 being constant ; for my classification of the wind strengths, although based on the 

 Beaufort scale, would almost certainly differ from a similar classification made by 

 another observer. 



Relation between the Meteorological and Electrical Conditions of the 



Atmosphere. 



dissipation and Wind. After what has been already said about the method of 

 estimating the wind strength, the following table cannot be regarded as final ; but 

 as it shows the influence of the wind as found from all the observations it is printed 

 here. It is of considerable interest to notice that the ratio q falls as the wind 

 strength increases. 



