224 Transactions of the South African Philosophical Society. 



Exactly as was found in the case of the hot winds of Durban,' 1 ' so 

 we find the temperatures and pressures of Kimberley well above the 

 normal during the first half of the week, with a sudden fall to a 

 lower temperature afterwards, and a gradual fall to a lower pressure. 

 The variations of temperature and pressure at Durban are in the 

 same direction as at Bast London, though they come rather later, 

 and the variation of temperature is much less pronounced. 



When the temperatures and pressures at East London and 

 Durban on the day of a hot wind at the latter place are compared 

 with the same elements on the day of a hot wind at the former, we 

 find some very striking dissimilarities. Thus when the hot wind 

 prevails at East London the barometer falls on an average during 

 four days to the minimum -247 inch at East London, and -223 inch 

 at Durban, the corresponding rises of temperature being 24° and 4° 

 respectively ; but when the hot wind is at Durban the barometer 

 falls in the same period of time to the minimum "356 inch at Durban 

 and *289 inch at East London, the corresponding rises of tempera- 

 ture being 24° at Durban and practically nothing at East London. 

 That is to say, the depression which determines such a wind is 

 actually deeper at East London when there is a hot wind at Durban 

 than it is at East London itself when the hot wind is there. But 

 there is this important distinction — that when the hot wind is at 

 East London the direction there is about north-westerly (i.e., from 

 inland), whereas when the hot wind is at Durban the wind at East 

 London is south-westerly (i.e., up the coast). 



Synoptic Elements during a Hot Wind at Durban, 



1886-1904. 





Pressure. 



Temperature. 





Durban. 



East London. 



Durban. 



East London. 



First day before 



inches. 

 30-151 

 30-130 

 30-058 

 29-795 

 30-136 

 30-131 

 30-145 



inches. 

 30-029 

 30-020 

 29-901 

 29-740 

 30-025 

 30-087 

 30-097 



o 

 80 



84 

 84 

 104 

 80 

 81 

 80 



o 

 71 



72 

 74 



Day 



Second day after 



73 

 71 



72 

 70 



Taking into account, therefore, the synoptic conditions prevailing 



* See J. R. Sutton, " Some Pressure and Temperature Results," &c., Trans. 

 S. A. Phil. Soc, vol. xi., part 4, p. 273. 



