238 
THE GEOLOGIST. 
NOTE ON THE GEOLOGY OF SUNDAYS RIVER, 
SOUTH AFRICA. 
By G. W. Stow, Esq., of Port Elizabeth. 
A friend and myself undertook a geological excursion a little 
before Christmas, along the banks of the Sundays River. We 
stai-ted on horseback, and extended our researches some sixty or 
seventy miles along its banks, examining every kloof and krantz 
that appeared at all promising. The incidents that befel one on such 
a trip but add a Hvely and pleasurable excitement to such an under- 
taking : now suddenly coming upon a cobra ; anon falling upon the 
the fresh spoor of a tiger ; finding ourselves fast on the side of a 
krantz, with the river running some hundred feet immediately below 
us ; being hooted at by baboons, for invading their solitary realms ; 
or, lastly, finding the river risen on our return in the evening, and 
having to make a dash — and swim, splashing through — as best we 
could on horseback (^vith nether garments tied around one's neck), to 
regain our quarters for the night. My friend was very successful, and 
made a collection of manybeautifulfossils. We discoveredin some places 
natural basins, in the hills bordering the river the sides and bottoms 
of which were literally strewed with scores of magnificent specimens 
of Trigonise and Pinnae broken out entire from the projecting shell- 
strata, — in fact, being so numerous that it was difficult to know which 
to select. 
I enclose rough sketches of the Koega Kopjis and of the St. Croix 
Islands, as they are now seen from this place. They appear so alike 
in their conformation — the former isolated quartzite hills rising from 
the plain, the latter islets some little distance from the mainland — 
that one is urged to the conclusion that their strata must be equally 
alike ; and that as the latter are situated now in the present, so must 
the former have been islands also, in the far more ancient ocean in 
byegone ages. 
The islands here spoken of I have not visited : but I have been 
informed by Dr. Rubidge, that they are quartzite also. 
That such was the case, with regard to the Koega Kopjis, is proved 
most conclusively by the following sketch of an exposed section, on 
the banks of the Koega River, about three hundred yards from the 
foot of the hills, on the north side towards the Sundays River. 
Here it will be noticed that the difierent strata vary most con- 
siderably in thickness ; and that from five, six, and more feet in 
thickness, they gradually decrease, as in some of the more central 
ones, until they are not more than a few inches. It is also very notice- 
able that the narrower the difierent bands of strata become, so in 
proportion their dip increases, — exactly, as it must have been as 
