formation of my
readers, I shall notice any particular district on either side of the
line I propose to touch upon, which may be worthy of notice. It would
appear that the first decided break in the sandstone formation which
penetrates into the county of Camden, is at Mittagong Range. It is
there traversed by a dike of whinstone, of which that range is wholly
composed. The change of soil and of vegetation are equally remarkable
at this place; the one being a rich, greasy, chocolate-coloured earth,
the other partaking greatly of the intertropical character. In
wandering over them, I noticed the wild fig and the cherry-tree,
growing to a much larger size than I had seen them in any other part of
the colony. Upon their branches, the satin bird, the gangan, and
various kinds of pigeons were feeding. Birds unknown to the eastward of
the Blue Mountains, were numerous in the valleys; and there was an
unusual appearance of freshness and moisture in the vegetation.

These signs of improvement, however, vanish the moment Mittagong range
is crossed, and sand-stone again forms the basis of the country to a
considerable distance beyond Bong-bong. At a small farm called the
Ploughed Ground, it is again traversed by a dike of whinstone, and a
rich but isolated spot is thus passed over. With occasional and partial
interruption, however, the sand-stone formation continues to an abrupt
pass, from which the traveller descends to the county of Argyle. This
pass is extremely abrupt, and is covered with glaucus, the low scrub I
have noticed as common to the sand-stone formation. A small but lively
stream, called Paddy's River, runs at the bottom of this pass, and
immediately to the S.W. of it, an open forest country of granite base
extends for many miles, on which the eucalyptus manifera is prevalent,
and which affords the best grazing tracts in Argyle. At Goulburn
Plains, however, a vein of limestone occurs, which is evidently
connected with that forming the ShoalHaven Gully, which is perhaps the
most remarkable geological feature in the colony of New South Wales. It
is a deep chasm of about a quarter of a mile in breadth, and 1200 feet
in depth. The country on either side is perfectly level, so much so
that the traveller approaches almost to its very brink before he is
aware of his being near so singular an abyss. A small rivulet flows
through the Gully, and discharges itself into the sea at ShoalHaven;
but this river is hardly perceptible