18 
To the Northward of the mine a high sandy table-land is seen, whilst just 
above this outcrop of mineral bearing country, the Carboniferous rocks again 
make their appearance; but here again, as on the Greenougli, there are no good 
sections or fossils, though springs break out in the same manner as on that river 
and on the Irwin. This is evidently due to the fact that many of these horizontally 
bedded Carboniferous rocks are impervious, which causes the water percolating 
through the sandstones from the higher country to the Eastward to come to the 
surface at their lower outcrop. 
This formation continues up the Murchison as far as the great bend, where 
the country opens out into what may be called the characteristic Murchison 
country, namely, large alluvial plains with low ranges of schistose rocks, con¬ 
taining quartz reefs, the ranges being mostly flat-topped and capped with a 
ferruginous sandstone, with here and there bold granite hills that are evidently a 
northern continuation of the lino of intrusive rocks that can be traced, down to the 
South coast. 
The Sandford and Impey, which are the two main branches, flow from the 
East, passing over very similar country to the river itself, namely, large alluvial 
flats with here and there bold range masses and peaks of granitic rock rising 
abruptly from the plain, or low ridges capped by horizontally bedded ferruginous 
sandstone. 
The Murchison rises in the edge of the broken table-land amongst the crystal¬ 
line rocks of the Robinson, Kimberley, and Glengarry Ranges, about 1,500 feet 
above sea-level. Many of these hills are capped by horizontally bedded sandstone, 
and intersected by numerous quartz reefs. They are surrounded by large alluvial 
flats of red clayey loam and sand, which are broken in places by red granite hills, 
evidently intrusive, which appear to extend in lines or belts across this part of the 
country. The whole of the upper course of this river lies through country of 
nearly the same character, viz., large flats of clay and sand flanked by Metamorphio 
hills containing quartz reefs and dykes of diorite, and generally capped with ferru¬ 
ginous sandstone. In the bed of the river, sandstone and travertine are of constant 
occurrence, in some places associated with large quantities of salt. 
This liver, although subjected to yearly floods of greater or less magnitude in 
its upper courses (where the pools become fresh or only slightly brackish), very rarely 
runs throughout its entire length, the flood waters being* lost on the large alluvial 
plains. When, however, these floods do reach the sea they are not altogether a 
blessing to the settlers on the Lower Murchison, for they carry the salt water 
which has accumulated in the large pools in the middle course# of the river down 
spoiling all the fresh water pools in lower part which are filled locally by the 
coastal rains. 
The large alluvial plains of the Murchison are celebrated for their mag¬ 
nificent water supply, for throughout this district it is possible to obtain water at 
a very slight depth. This is being now taken advantage of by the sheep farmers 
who are opening their old wells out into tanks, with sides at such an an4e that the 
sheep can walk down and water themselves. 
This water supply is generally found under a magnesian deposit (locally 
called opaline), which has evidently been formed by the evaporation of the water 
which is slightly charged with this mineral, and, as it has cemented the sand and 
shingle together, it is very hard stuff to work through. 
The country nearer the coast consists of a series of flat-topped hills or table 
lands of clay, sandstones, and limestones of Cretaceous and Oolitic am- covered in 
many places by sand plains. Where streams occur they have cut through the 
newer rocks, removing large portions and exposing the Underlying crystalline 
rocks, of which granite is the most abundant, the others being chiefly mica schist 
gneiss, and quartzite, with numerous dykes of diorite, granite, and fe’lstone 
