SOUTHERN AFRICA. 295 
was necessary to lift the waggons by main strength. Just as 
we reached the summit, the weather, which had been re- 
markably pleasant, the thermometer standing at 74°, now 
began to be overcast, the wind blew fresh, and shortW after 
an immense sheet of black vapor was observed to approach, 
borne upon the south-east wind from the sea. Ascending 
rapidly in rolling volumes, it completely immersed us upon 
the summit of the mountain. The temperature of the air 
was immediately decreased to 39° of Fahrenheit. Before 
our three waggons had got over the highest peak, the weather 
began to clear up, and it was then curious enough to observe 
all that tract of country lying between the mountains and 
the sea involved in dense clouds, and deluged apparently 
with heavy rain, whilst the northern side of the same moun- 
tains enjoyed a sunshine unsullied by a single cloud. 
The instability of the climate of the southern angle of 
Africa has frequently been noticed in the course of these 
sketches ; yet a more remarkable instance of it had not per- 
haps occurred than in the present situation. An elevation of 
about one thousand feet, or little more, produced a variation 
of temperature, in the course of two hours, equal to thirty- 
five degrees. It afterwards appeared, that, on the same day, 
being the longest in the year, snow had fallen and lain for 
some time upon the same chain of mountains, close behind 
Zwellendam, where the surface is not by any means parti- 
cularly lofty. 
The descent of the Duyvil's kop was much more gradual 
than had been ihe ascent, and the smooth grassy surface of 
