78 



MR. GEORGE C. SIMPSON ON THE 



over the range he investigated. Later GOCKEL returns to this point * and throws 

 out the suggestion that the increase in the dissipation is due to the increase which 

 the ozone in the atmosphere undergoes as the temperature rises. In Karasjok the 

 temperature fell so low during the winter that I was able to observe the influence 

 of temperature on the dissipation at very much lower temperatures than had ever 

 been done before, obtaining sixty observations with the temperature between - 40 

 and - 20 C. Table XII. shows the results, which, in the main, confirm ZOLSS'S 



TABLE XII. Dissipation and Temperature. 



observations. The temperature has a great effect on the dissipation, for it rises from 

 83 with temperatures between 40 and 20 C. to 4'95 with temperatures 

 between 10 and 15 C., and when the results for the whole year are considered the 

 relation is practically linear. But here again attention must be called to the fact 

 that the very low temperatures were always accompanied by calm weather ; and 

 that there was very much more wind during the summer when the high temperatures 

 were obtained than during the winter with its low temperatures. It is interesting to 

 note that temperature has no apparent effect on the ratio q. 



lonization and Relative Humidity. It will be seen from Table XIII. that when 

 the whole year is taken into account the effect of the relative humidity on the 

 ionization is very similar to its effect on the dissipation. That is, the amount of 

 ionization decreases with an increase in the relative humidity, while the ratio r 

 increases. But it is very interesting to note that when the winter and summer 

 results are taken separately this effect is hardly apparent at all. No definite effect 

 of the relative humidity on the positive ionization can be detected during either the 

 winter or summer six months. While the negative ionization is slightly affected 

 during the winter, no effect can be seen during the summer. Nevertheless, during 

 both winter and summer the value of the ratio r increases regularly with the relative 

 humidity. 



* ' Phys. Zeit.,' 5, p. 257, 1904. 



