150 



I'EPI'ER THEE AS A CAUSE OF HAY FEVEU. 



tco small to be of any practical value. The number of these 

 very light showers will be evident from an inspection of Table 

 III, which shows the daily rainfall for three years. To select 

 two examples : in December, 1919, though rain was recorded on 

 8 days, the total for the month was only 0-50 inches, being an 

 average of 006 inches; and for November, 1921, a more extreme 

 case, rain on 17 days totalled only 1'36 inches, or an average of 

 0.07 inches. A study of this table also reveals the interesting 

 fact that the amount of rain most frequently recorded for Bloem- 

 fontein is " 0.00 " inches, which, I understand, is the official 

 method of indicating a shower of less than one-hundredth of an 

 inch. These showers temporarily soften and cool the air, but 

 are rarely of any real benefit to vegetation. 



Table II 

 Bloemfonteix : IMonthlv Rainfall for three years. 



In Table II an attempt has been made to allow for this 

 wastage by omitting showers of less than 0'3 inch and taking 

 as 2 inches amounts greater than this. The result for the three 

 years 1919-1921 is that 



a total rainfall of 12 inches in 1919 becomes 6 dnches 



a total rainfall of 23 inches in 1920 becomes IT) inches 



a total rainfall of 22 inches in 1921 becomes 10 inches 



