SOUTHERN AFRICA. 337 
meter ftanding at 74°, now began to be overcaft, the wind blew 
frefh, and fliortly after an immenfe fheet of black vapor was 
obferved to approach, borne upon the fouth-eaft wind from the 
fea. Afcending rapidly in rolling volumes, it completely im- 
merfed us upon the fummit of the mountain. The tempe- 
rature of the air was immediately decreafed to 39° of Fahren- 
heit. Before our three waggons had got over the highcft peak, 
the weather began to clear up, and it was then curious enough 
to obferve that part of the country between the mountains and 
the fea involved in denfe clouds, and deluged apparently with 
heavy rain, whilft the northern fide of the fame mountains 
enjoyed a funfhine unfullied by a fingle cloud. 
The inftability of the climate of the fouthern angle of Africa, 
has frequently been noticed in the courfe of thefe (ketches ; 
yet a more remarkable inftance of it had not perhaps occurred 
than in the prefent fituation. An elevation of about one thou- 
fand feet, or little more, produced a variation of temperature, 
in the courfe of two hours, equal to thirty-five degrees. It 
afterwards appeared, that, on the fame day, being the longeft 
in the year, fnow had fallen and lain for fome time upon the 
fame chain of mountains, clofe behind Zwellendam, where ic is 
not particularly lofty. 
The defcent of the Duyvil's kop was much more gradual 
than had been the afcent, and the fraooth gralfy furface of the 
northern fide was now changed into an extenfive fhrubbery, 
among which the moft confpicuous plants were heaths and pro- 
teas of amazing fizes ; one of the latter having a round thick 
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