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A paper ‘* On the Geological Phenomena in the Vicinity of Cape 
Town, Southern Africa,” by the Rev. W. B. Clarke, F.G.S., was 
read. 
Mr. Clarke commences by stating, that having derived no advan- 
tage from the labours of previous geologists, his remarks must be 
regarded as independent of any prior description. He arranges his 
‘details under the heads of Physical aspect, Mineral structure, and 
Geological changes. . 
1. Physical aspect.—The leading physical features are the mag- 
nificent serrated mountains called Blue Berg or Hottentot’s Hol- 
land, which stretch northward for many miles into the interior; 
and the promontory which extends from Table Mountain to the 
Cape of Good Hope. Each of these ranges consists of flat-topped 
masses interspersed with pyramidal or pointed peaks, and separated 
by deep ravines ; and Mr. Clarke states that their outline is evidently 
owing to deep vertical fissures intersecting horizontal strata, proving 
also that the Table Mountain is not a solitary example of the fea- 
ture to which it owes its name. A level area extends from the base 
of the Blue Berg to the shore; and between the southern termina- 
tion of that range and Table Mountain, is the low sandy district 
called the Table Flats, forming an isthmus between Table Bay and 
False Bay. A prominent but subordinate physical feature is the 
Lion’s Hill, situated below Table Mountain; at the entrance of the 
Bay is Robben’s Island, and between the base of the Blue Berg and 
the shore is a low range of hills of limited extent. 
False Bay is bounded on the west by the Cape Promontory, atl 
on the east by a continuation of the Blue Berg, presenting the same 
physical structure and geological aspect as the Promontory. 
Mineral structure and position.—In detailing the composition of 
the rocks and the associated pheenomena, Mr. Clarke describes sepa- 
rately, and in the following order, first, each of the principal physical 
masses ; namely, the Lion’s Rump, the district between Green Point 
and Camp’s Bay, that between Camp’s Bay and Cobler’s Hole, the 
Kloof, and Table Mountain; and secondly, the modern deposits, 
springs and detritus. 
The Lion’s Rump.—The lowest deposit at the Lion’s Rump varies 
in characters from a glossy soft slate to a hard and siliceous, as well 
as a crystalline schist, and occasionally to a rock as close-grained as - 
bassanite. The partings of the masses are stated to be frequently 
lined with a substance resembling soapstone and serpentine; and 
the intersection of the joints giving the strata a somewhat columnar 
structure, the rock presents a basaltic aspect. The true line of bed- 
ding is not easily to be distinguished, but the author is of opinion 
that it ranges between north and south. The cleavage, where it 
can be detected, is nearly perpendicular to the horizon. Overlying 
these schists and composing the upper part of the hill, is a yellowish, 
argillaceous and sandy laminated rock, which presents the same 
jointed structure and cleavage as the schist; and owing to the in- 
tersection of the joints, the beds divide into wedge-shaped masses, 
or@regular prisms with pyramidal terminations. Mr. Clarke is of 
