BASALTIC AND ALLIED ROCKS. 503 
united, and the latter so irregularly permeated and intersected by the 
former, that considerable difficulty is experienced in tracing out the 
line of separation. 
The character of this conglomerate may be well studied at the foot 
of the first cliff north of Kiama Point. It is exceedingly rough and 
ragged in its features. It generally consists of a clayey base tinged of 
various light shades of colour, either red, purple, green, flesh-tint, or 
yellow, and containing imbedded fragments of the several varieties 
of basalt. Large masses are occasionally scattered through it; one 
observed was fifteen feet square and five feet high, and seemed to be 
a knoll projecting from the solid basalt below. In some parts the 
fragments seem to be entangled in the solid basalt, and appear to have 
been enveloped during the fusion of the latter; and they are often 
three or four feet in diameter, though generally about as many inches. 
The exterior is rough and sometimes scoria-like; rarely they are 
somewhat rounded. 
The clayey base is often baked 
to a flinty chert or jasper, which is = = on ee 
usually of a deep-red or brownish- DSS OSS 
in s 1] ig SS, SSSA 
red colour, but in some places is _-\ =n, Ca.“ 
Bee 4) Sie US) 
striped with gray and brown. In “al > Ba Can 
the annexed figure, the conglome- <n Se we ~ RY 
rate is intersected by a network of mae | ae 
: - = : Ni NNO “SS, 
veins of jasper; it was taken on a 
the first point south of Kiama. 2» S~ ~ i > << 
The four principal veins are from 
three to seven inches wide and nearly parallel; yet they are extremely 
irregular in form and vein-like in their branchings. 
When this baked conglomerate has been worn by the sea, as is well 
shown near the Kiama blow-hole, it sometimes presents all the cavern- 
ous structure and rough points of a volcanic scoria; and the resem- 
blance is so close, that in hand specimens they could hardly be dis- 
tinguished. 
The heat of the layers of basalt has produced important changes in 
the sandstone below. The red colour of the rock near Kiama is evidently 
an effect of this heat. At Geringong Boat Harbour, a layer of red sand- 
stone, twenty-five feet thick, hes below the basalt; and beneath the 
whole, there is the common gray Wollongong rock. At Rocky Cove, 
the continuation of the same red layer is scarcely at all altered from 
the gray colour, although much hardened and vertically fractured. 
