142 TRAVELS IN 
called by miners white filver ore^ on account of the large pro- 
portion it has been found to contain of that metal. It is well 
known that all galenas contain more or lefs of filver; and it 
has been obferved that thofe whofe configuration is leaft diftindt 
have the greateft proportion, the heterogeneous metal having 
difturbed and obftru6led the natural arrangement of the parti- 
cles, which would be that of a mathematical cube if perfectly 
pure. The vein of the ore was about three inches wide and an 
inch thick, and it appeared to increafe both in width and thick- 
nefs as it advanced under the ftratum of rock with which it was 
covered. The gangue or matrix was quartoze fand-ftone of a 
yellowifli tinge, cellular and fibrous, harfh to the feel, and eafily 
broken. 
Some experiments were formerly made, in a rough way, at 
the Cape of Good Hope, upon fpecimens of this identical vein 
of lead-ore, by Major Van Dhen, an officer in the Dutch fer- 
vice, and the refult of thefe proved it to be uncommonly rich 
in filver. According to this gentleman's ftatement of the affay, 
two hundred pounds of the ore contained one hundred pounds 
of pure lead and eight ounces of filver. Should this on a more 
accurate trial turn out to be the cafe, it may hereafter prove a 
valuable acquifition to the colony. Lead mines, it is true, are 
generally very deep below the furface of the ground, and the 
working of them is both troublefome and expenfive. But at 
this place a vein of rich ore, fhewing itfelf at the furface, gives 
reafonable grounds for prefuming that the large body of the 
mine is at no great depth, and if fo it might be worked with 
great advantage. The furrounding country is particularly 
favor- 
