Greywacke.—­Colour grey, of light hue, or dark, with black specks.  Soft.—­Composition of a part of the ranges that form the valley of the Morumbidgee.

Serpentine.—­Colour green of different shades, striped sulphur yellow; slaty fracture, soft and greasy to the touch.  Forms hills of moderate elevation, of peculiarly sharp spine, resting on quartz.  Composition of most of the ranges opposite the Doomot River on the Morumbidgee, in lat. 35 degrees 4 minutes and long. 147 degrees 40 minutes.

Quartz.—­Colour snow-white; formation of the higher ranges on the left bank of the Morumbidgee, in the same latitude and longitude as above; showing in large blocks on the sides of the hills.

Slaty Quartz, with varieties.—­Found with the quartz rock, in a state of decomposition.

Granite.—­Succeeds the serpentine, of light colour; feldspar decomposed; mica, glittering and silvery white.

Sandstone, Old Red.—­Composition of the more distant ranges on the Morumbidgee.  Forms abrupt precipices over the river flats; of sterile appearance, and covered with Banksias and scrub.

Mica Slate.—­Colour dark brown, approaching red; mica glittering.  The hills enclosing Pondebadgery Plain at the gorge of the valley of the Morumbidgee, are composed of this rock.  They are succeeded by

Sandstone.—­Which rises abruptly from the river in perpendicular cliffs, of 145 feet in height.

Jasper and quartz.—­Colour red and white.  Forms the slope of the above sandstone, and may be considered the outermost of the rocks connected with the Eastern or Blue Mountain Ranges.  It will be remembered that jasper and quartz were likewise found on a plain near the Darling River, precisely similar to the above, although occurring at so great a distance from each other.

Granite.—­Light red colour; composition of a small isolated hill, to all appearance wholly unconnected with the neighbouring ranges.  This specimen is very similar to that found in the bed of New-Year’s Creek.

Breccia.—­Silicious cement, composed of a variety of pebbles.  Formation of the most westerly of the hills between the Lachlan and Macquarie Rivers.  This conglomerate was also found to compose the minor and most westerly of the elevations of the more northern interior.

Chrystallised Sulphate of Lime.—­Found embedded in the deep alluvial soil in the banks of the Morumbidgee River, in lat. 34 degrees 30 minutes S., and long. 144 degrees 55 minutes E. The same substance was found on the banks of the Darling, in lat. 29 degrees 49 minutes S., and in long. 145 degrees 18 minutes E.

A reference to the chart will show that the Morumbidgee, from the first of the above positions, may be said to have entered the almost dead level of the interior.  No elevation occurs to the westward for several hundreds of miles.  A coarse grit occasionally traversed the beds of the rivers, and their lofty banks of clay or marl appear to be based on sandstone and granitic sand.  The latter occurs in slabs of four inches in thickness, divided by a line of saffron-coloured sand, and seems to have been subjected to fusion, as if the particles or grains had been cemented together by fusion.