1812. 
HILLS OF SHINING BLACK ROCKS. 
43 
we entrusted them with the office of driving forward our sheep and 
loaded oxen. And, indeed, our fellow-travellers, Riizo and Kaabi, 
evinced a truly honest and friendly inclination towards us ; so that, 
without meaning to neglect that prudent circumspection so neces- 
sary to a European travelling in this country, I would as willingly 
- have committed myself to them, as to my own countrymen. The 
former of these two, was naturally of a more reserved disposition, 
but was always ready to lend any of the Hottentots his assistance, 
whenever he thought he could be useful ; and seemed as much at his 
ease with them, as with his own friends. 
During this day's ride we passed many small rocki/ hills of a 
remarkable kind, presenting a character different from all which 
I had hitherto observed. They were generally quite bare, especially 
on the top, and were composed of huge rounded pieces of rock, 
most frequently about five feet in diameter, piled loosely upon each 
other, and apparently without any earth between them : as may be 
seen in the first plate. But their most striking character was the 
smooth shining blackness of their surface, not unlike that of iron 
polished with black-lead. * They were composed of ' primitive 
green-stone,' probably containing iron, from which they derive their 
lustre and color after long exposure to the atmosphere ; but within, 
on being broken, they were found to possess their proper greenish or 
blueish hue. Rocks of this species occur very frequently in various 
parts of Southern Africa, but till now none had been seen with so 
glossy a surface. The rocks at Dwaal river f , and in that vicinity, 
were, excepting this particular, not very different from these, and 
both, when fitly poised, were capable of giving a sound like that of 
a large bell ; and both, I believe, affect the magnetic needle. They 
must be considered as boulder stones, though found on the tops 
of the hills ; but beyond this, conjecture can afford nothing 
* At a subsequent period of these travels, ?-ocks of die same nature and appearance 
were observed in abundance along the course of the Nugariep or Black River ; and I am 
inclined to suppose that it was this circumstance which gave rise to the name which the 
stream bears among the natives. 
f Described in the first volume, at page 277. 
G 2 
