54 Personal Observations in the 
who are proverbially the best riders in the country, and sur- 
pass anything we read of concerning the horsemanship of 
other countries; this superiority being attributable only to 
the rugged nature of the district in which they reside. 
II. Melbourne, as is well known, rests on strongly com- 
pressed silurian strata, entirely surrounded by the basalt 
formation. Extremely minute fossils (Aérypa) are found in 
these strata; but those typolites obtained near Flemington, 
scarcely two miles from Melbourne, and of which I have pro- 
cured living specimens from Western Port Bay, are large and 
perfect. The latter are petrified in brown iron ore belong- 
ing to the uppermost tertiary formation. 
- The extensive plains between Melbourne and Mount 
“Macedon, as has been stated in the former part of this 
paper, belong almost entirely to the basalt, or, as some Eng- 
‘lish geologists term it, the trap formation. The rocks of 
this class are composed principally of felspar and augite, the 
latter predominating; and a soil of very superior capabilities 
arises from their decomposition. 
The trap rocks which occur throughout Victoria, I have 
‘arranged under two distinct heads, viz., basalt proper, and 
dolerite; the former a black homogeneous mass, sometimes 
‘impregnated with different zeolites and iron ore. That 
' both are the result of volcanic action there cannot be the 
“slightest doubt, as they exhibit the most unmistakable signs 
of having been once in a molten state. 
_ The different varieties of basalt which occur in the plains 
above mentioned are :— 
* 1, Common basalt or bluestone; in columnar platforms 
and irregular boulders. 
. Porous basalt in irregular forms; on account of its 
porosity unfit for building purposes. 
- 3. Pumice stone, like basalt. Swims in water; attracts 
and retains the heat very powerfully. 
» 4, A lithodomous mass of an ochre-brown colour ; easily 
crumbled. It is questionable whether it be not of 
aqueous origin, its formation taking place when the 
volcanic power was finally subdued. 
5. Black soil of a crumbling nature. The decomposition 
of this species produces a soil highly valued for agri- 
cultural purposes. When mixed with clay the ground 
becoming what is termed by the colonists “ honey- 
combed;” and if stones be intermingled with it, mounds 
are raised, designated “ dead men’s graves.” 
tS 
