308 W. J. CLUNIES ROSS. 
cappings to some of the hills. If we travel south, about ten 
miles, we reach Carcoar, another interesting locality, where there 
are dense holocrystalline, coarse-grained, basic rocks, which may 
be classed as gabbro. A section of one of these, obtained from a 
cutting near Carcoar station, shows it to consist mainly of 
plagioclase felspar, together with a green mineral in large crystals 
but without a definite outline. The rock appears to be a good 
deal weathered and one feels rather doubtful about naming the 
latter mineral. It is probably an altered pyroxene, and appears 
schillerized but does not shew the strong cleavage of diallage 
very clearly. It is strongly dichroic and may be passing into 
hornblende. Mr. Curran mentions obtaining sections of an 
apparently similar rock from Carcoar.’ 
Near Blayney, in a cutting on the Oarcoar line, a dyke of a 
fine porphyritic rock occurs, having white prismatic crystals of 
felspar scattered through it. A similar rock, in microscopic 
character, is well known at Dripstone, near Wellington. I have 
not a section of either of these, and one from a similar rock 
obtained near Carcoar is very much weathered. Mr. Curran 
mentions similar rocks as occurring near Cowra and calls them, 
and also the Wellington rocks, diabase porphyrites. This is the 
name which I applied provisionally to the Blayney rock before 
seeing his paper. The specific gravity of a specimen was 2°86. 
The nearest approach to a true basalt was obtained from the 
top of a hill near the Blayney cemetery. It is a close-grained, 
black rock, which under the microscope is seen to be an aggregate 
of rather coarse crystals, much weathered, and of quite a different 
type from the Bathurst basalts. From two or three determina 
tions, the silica was found to be forty-nine or fifty per cent. The 
alumina was not as satisfactorily determined but appeared to.,be 
fully 20 per cent., ferric oxide 13°5, lime 6-72, magnesia 4°86. 
The specific gravity varied in different specimens from 2°8 to 3. 
Blayney is on the Belubula River, which belongs to the Lachlan 
Eo Se 
1 “The Microscopie Structure of Australian Rocks,” p. 46. 
