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HENRY A. HUNT. 



and of less than their ordinary violence, when the same region is 

 visited by persistent rains with overcast skies. In other words, 

 seasons of drought and desolation and seasons of deluge are both 

 inimical to the existence of bursters. 



The following theory is tentatively submitted, to account for 

 the greater prevalence of bursters during what may be called a 

 moderately dry season. This term is used here to indicate, not 

 so much a season in which the rainfall does not exceed the 

 average, as one in which the number of rainy days is a shade 

 below the average. It will be remembered that strong southerlies 

 have been said to result from energetic anti-cyclones ; also that 

 energetic anti-cyclones bring with them possibilities of great 

 extremes in our summer temperatures. But since in summer 

 their sphere of action is in high latitudes the weather of the 

 northern parts of Australia is controlled chiefly by tropical 

 depressions, and consequently great heat prevails there as a rule. 

 Now if, after a period of hot weather, rain were suddenly pre- 

 cipitated on this northern area, the consequence would be a great 

 uprush of air with the vapour produced by the rain falling on 

 heated ground, and a consequent inrush of air from southern 

 areas. 



RECURRENCE AND DURATION OF BURSTERS. 



Bursters are not only uncertain in their duration, but the periods 

 of their recurrence are extremely erratic. Two have been fre- 

 quently known to take place within twenty-four hours ; between 

 two others, an interval of a month has been known to elapse. 

 The shortest one recorded extended over a period of three hours ; 

 the longest covered the space of ten days. These figures of course, 

 embrace all the variations of the wind during the continuance of 

 the storm. 



SHORT-LIVED BURSTERS. 



The short-lived bursters are generally experienced during a 

 seasonal prevalence of north-east winds ; those of longer duration 

 are usually met with during a southerly prevalence. 





