(*Footnote. This book is already almost too full of plates and I beg to refer the geological reader to my three-sheet map of the Colony for the superficial forms and extent of these valleys.)
WELLINGTON VALLEY.
In the year 1830, after I had traced out the new line of descent from the Blue Mountains to the interior country by the pass which I then named Mount Victoria, I extended my survey to the heights beyond Wellington Valley. This includes a rich alluvial tract watered by the river Bell, one of the principal tributaries of the Macquarie, and is about 170 miles to the westward of Newcastle. It is bounded on each side by a compact calcareous rock resembling the mountain limestone of England and rising on the east side to about 100 feet above the Bell.
PLATE 42: GEOLOGICAL MAP OF WELLINGTON VALLEY.
From Nature and on Stone by Major T.L. Mitchell.
Published by T. and W. Boone, London.
On the west side of this valley hills of greater elevation, consisting of a red sandstone and conglomerate, extend parallel to the limestone; and on the east side of it is another range composed of trap-rocks. The basis of a tract still further eastward, dividing the watershed of the interior from that which sends its streams to the sea is, as has been already observed, of granite.
The limestone presents a naked and rugged surface composed of pointed, weather-worn blocks between which are small crevices leading to caves and fissures. From these crevices a warm air ascends, accompanied by a smell peculiar to the caves. The worn aspect of the external rock, resembling half-dissolved ice, is very remarkable, particularly near the largest caverns.
An account of the survey of these caves was communicated to the Geological Society in a paper read on the 13th of April 1831, of which an abstract was published in its Proceedings, but the particulars respecting the animal remains found by me have derived great additional importance from the discoveries made by Professor Owen since my return to England. I may be excused therefore for again calling attention to the situation of those curious caves respecting which the following details are now published with the consent of the Council of the Society.
LIMESTONE CAVERNS.