And Soils of Victoria. 263 
the phosphates. Now, although volcanic rock, especially if 
augite predominate in its composition, may occasionally con- 
tain a less proportionate quantity of the alkalis, or even of 
the phosphates than some other rocks, yet, the greater 
intensity of the disintegrating action generally observable in 
soil derived from volcanic rock would often furnish so large 
and continuous a supply of the chief inorganic constituents 
required by cereal crops, as to. render the renovation of the 
soil, by disintegration still going on therein, quite equivalent 
to the abstraction of inorganic matter by incessant cereal 
erops. In this way only can I account for the inexhaustible 
soils already alluded to, at Prospect and Illawarra. 
But in Victoria we possess extensive tracts of land, not 
yet brought under cultivation, whose soils seem to me to be 
under precisely the same conditions of derivation and disin- 
tegration as the soils of those favoured, but very limited 
localities in New South Wales; and much of this land in 
Victoria consists of well-grassed plains, easily brought under 
cultivation. I admit that the soil in connexion with the 
recent lava, north of Melbourne, is not always rich, but may 
yet, on the whole, be pronounced so far good as to justify the 
opinion I now venture to submit to you, that in Australia, 
soils derived from the disintegration of volcanic rocks are 
more generally fertile than those connected with aqueous or 
plutonic rocks. 
As the available surface of Victoria embraces a much ™ 
greater extent of soil thus derived, than that of any other 
Australian Colony, I have therefore concluded that the natural 
advantages of Victoria, in reference to the extensive and 
successful production of ordinary cereals, greatly preponderates 
over those of her neighbours. 
In South Australia the only volcanic district worth noticing 
is that around Mount Gambier on the confines of the colony. 
In Tasmania volcanic rocks are more prevalent, but are very 
frequently associated with steep densly wooded surfaces. In 
New South Wales the sandstone of the central counties is, 
in a few localities, displaced by trap dykes, as already me- 
tioned; in the northern part of that territory, the volcanic 
rocks are mostly confined to densly wooded mountain ranges. 
But if the disintegration of volcanic rocks in Victoria has 
rendered so much surface pre-eminently adapted for corn crops, 
the disintegration of another class of rock very prevalent near 
Melbourne,—clay slate,—has tended to produce much soil 
that would prove, in the very highest degree, favourable not 
only to the growth of the vine, but also to the production 
of wines of very superior quality. 
