1811. 
THE PRINCIPLE OF ATMOSPHERIC HEAT. 
497 
earth's axis to its orbit, should give us all the seasons of the year ; 
how admirable ! how beautiful ! 
It can be no argument against this theory, that, within the tropics, 
perpetual snow covers the summits of the loftiest mountains, and 
that local circumstances occasion some variation in the regular heat 
of the climate. These depend on other causes, more complicated, 
and less satisfactorily explained ; unless it be, that the capacity for 
heat, which the atmosphere possesses, may be in proportion to its 
density ; and, consequently, as its rarity increases generally in the 
ratio of its elevation above the level of the sea, its power of retain- 
ing the heat of the sun's rays will in the same ratio decrease. This 
principle seems to offer an explanation of some anomaHes in atmo- 
spheric heat ; and, supposing it universal, it is easy to conceive how 
the heat of our planets may be equalized, by atmospheres of in- 
creased density, suited proportionally to their distance from the 
sun. From this principle it would also follow, that the great im- 
mensity of space, in which our solar spheres revolve, is subjected to 
the extreme of cold. 
2^th. A strange Hottentot from the Cape colons/, arrived at 
Klaarwater, having found his way alone, on foot, unarmed, and 
without any other guide than the track of our waggons. The ac- 
count he gave of himself was, that he had been in the service of 
Piet Mulder, a boor in the Roggeveld ; but that latterly he had 
been living in a kraal, of which a Bushman, known by the name of 
Ruyter, was captain or chief ; and that the reason of his coming to 
Klaarwater was to see his sister, the wife of old Moses. Yet he was 
here, by almost every one, strongly suspected of being a runaway ; 
and, from his manners and conversation, he appeared to me to be 
half a simpleton. He was not aware, he said, that Klaarwater was 
so far from the colony, although he was only nine days on the road 
from the Sack river to the settlement at the Kloof in the Asbestos 
Mountains, including two days at the Karree Mountains, which he 
spent at the kraal of the Bushman captain Goedhart, by whom he was 
treated in a friendly manner. Near Carel Krieger's Grave lie was met 
by two Bushmen, whom, from their manners, he suspected of having 
3 s 
