116 THE VICLORIAN NATURALIST. 
and yet the descent beneath is almost perpendicular for hundreds of 
feet, and concerning Abrupt and Sturgeon precisely the same thing 
may be said, if one faces east instead of west; in the case of the 
latter mountains, immense basaltic plains commence from their very 
base, no further outcrop of sandstone strata occurring to the east 
in that part of the colony. 
Tt is necessary to remember that both the two generally parallel 
ranges, Victoria and Serra, have their steep sides facing the east, 
and yet they are only separated by ten or twelve miles of flat country, 
so that when their low angle of dip, (10° to 20°), is taken into 
consideration, it is evident that neither anticlinal nor synclinal curve 
could ever have existed between them, and one is therefore forced to 
the conclusion that the intervening valley is mainly one of 
denudation, and that both ranges were originally connected, form- 
ing part of one mighty mountain chain. It is probable that 
atmospheric degradation first commenced in the joints of the rocks, 
or along some great lines of fault. The whole series is very much 
jointed, and on this account the ranges wear away rapidly, not only 
on the bold rocky escarpments of their steep sides, but also on their 
opposite or sloping ones, producing great cracks and fissures, which 
in the course of time will widen out into deep gullies, bounded on 
either side, as the Victoria Valley is, by parallel ranges of hills, 
both dipping in the same direction. The actual amount of 
denudation must have been enormous, for undoubtedly atl these 
ranges were at one time very much higher than they are now, how 
much higher can only be estimated by a series of the most careful 
obseryations. 
The rocks throughout the whole formation are of an eminently 
sandy nature, and generally coarse grained, m some places being 
much harder than in others, as at Mt. Arapiles, where they are of a 
highly silicious character, and extremely hard. In all the ranges, 
quartz pebbles are abundantly scattered throughout the rock masses, 
and on a few of the heights, well developed, though small, erystals 
of quartz may occasionally be found. In many places, especially in 
the Victoria Range, the rocks split very readily, furnishing excellent 
materials for flagging, &c. Owing to the iron which most of the 
rocks contain, they have generally a rusty, stained appearance, but 
in some localities this ingredient is wholly absent, and then they are 
of a white colour, and if fine enough in grain, pass into a beautiful 
freestone. This is the case at the base of Mt. Abrupt, where 
quarries have been opened, from which a most valuable building 
stone is obtained. The handsome spire of the Anglican Church at 
Hamilton is constructed of this stone, and after many years of 
exposure does not show the slighest stain of iron oxide. The 
stone, I am told, is easily worked when fresh from the quarry, and 
as it exists in inexhaustible abundance, at a distance of only three 
