1842.] Climate of the Cape of Good Hope. 213 



season, unlike our Indian scorching hot winds, is cool and refreshing even 

 in the hottest weather, and not being so highly charged with humidity 

 as the northerly winds, the vapour it contains frequently passes over 

 the mountain without becoming visible. Oftener, however, it is chang- 

 ed into a mist or cloud, which covers the top of the mountain, and is 

 seen on the lee, or Cape Town side, rolling down in large fleecy volumes, 

 till it reaches a warmer temperature, when it again becomes invisible. 

 The elevation of this vanishing point varies with the hygrometric state of 

 the atmosphere, and the line, thus formed, is so distinct that were 

 degrees to be marked on the perpendicular cliffs which over-hang Cape 

 Town, a gigantic, but correct hygrometer would be furnished. I may here 

 express my regret, that I possess no notes of the hygrometric condition 

 of the atmosphere of the Cape, sufficiently accurate to be recorded. 



The different eddies and counter- currents of air produced by the 

 influence of the mountain, and by the interruption it occasions to the 

 general current of air, are also interesting phenomena. Among others, 

 a remarkable one is often experienced by ships entering the Bay with a 

 fair wind. On reaching a certain point they are frequently taken a-back, 

 and find themselves in a strong breeze blowing right out of the Bay ; and 

 few who have lived at the Cape can have failed to observe occasionally, 

 a northerly and a southerly wind blowing at the same moment in 

 different parts of the Bay, a line of confused ripple clearly marking the 

 limits to which the adverse winds, extend ; and I may add another curious 

 appearance I have repeatedly observed at Wynberg in winter, when north- 

 westerly winds are bringing large clouds over the mountains; viz. a cir- 

 cular spot of blue sky in the direction of Constantia, about 10° to 15° in 

 diameter, and about 20° from the zenith, on reaching which the clouds be- 

 come invisible, but after passing it, they resume their former appearance. 

 It may probably be accounted for by their meeting at that point a cur- 

 rent of rarefied air, which having found its way through a neighbouring 

 gap in the range of mountains, has not been cooled by passing over 

 their summit. Those acquainted with these localities well understand 

 that the gap alluded to, is that through which the road to Hout's Bay 

 passes. 



I may conclude these remarks, with a memorandum of the mean 

 temperature of Cape Town, and three other localities in the interior, 

 extracted from a printed statement I fell in with at the Cape, but I can 



