SOUTHERN AFRICA. 17 
The reasoning that suggests itself on tliese facts will lead 
to the followino; conclusion : — that the cisterns or cavities in 
the sandstone mountains, being corroded and fretted away, in 
the lapse of ages, to a greater depth than the openings or 
conduits which might, perhaps, at one time, have given their 
waters vent, the springs can no longer find their way upon the 
surface, but, oozing imperceptibly between the granite and 
the sandstone, below the general level of the country, glide 
in subterraneous streams to the sea. 
I am the more inclined to this opinion from the experience 
of several facts. When Admiral Sir Roger Curtis directed a 
space of ground, between the Admiralty-house and the shore 
of Table Bay, to be enclosed as a naval yard, the workmen 
met with great impediment from the copious springs of pure 
fresh water that rushed out of the holes, which they found 
necessary to sink in the sand, for receiving the upright posts. 
It is a well known fact, that on almost every part of the 
isthmus that connects the mountainous peninsula of the Cape 
to the continent, fresh water may be procured at the depth 
of ten or twelve feet below the sandy surface. Even in the 
side of the Tyger Hills, at an elevation of twenty feet, at 
least, above the general surface of the istlmius, when the 
workmen were driving a level in search of coal, a copious 
stream of water was collected within it, in the month of 
February, Avhich is the very dryest season of the year. 
And on boring, for the same purpose, on A'Vyni)erg, they 
came to a rill of water at the depth of twenty feet below 
tlie surface. 
VOL. II. D 
