Cpe a eae CP ae Re eS —— ae ee a ia) 
PROCEEDINGS OF SECTION C. 451 
wind alone.”* In support of his argument he also instances the 
Bermuda sandstone, which is an exactly similar formation, 
quoting as follows from Jones’ Guide to Bermuda :—‘In the 
islands of Bermuda a similar formation is met with. Although 
generally very low, some parts of these islands rise to 250 feet 
above the sea level, consisting of various kinds of limestone rock, 
sometimes soft and friable, but very often hard, and even 
crystalline. It has been put beyond a doubt, by a long-continued 
series of observations, that the rocks are all due to the wind, 
which blows up the sand from the beach, and which itself is 
derived from coral and shells. The rain dissolves portions of the 
lime and consolidates it.” 
As might be expected from its mode of formation, the deposit 
is remarkable for its constant change of dip, which may vary 
from 0 deg. to as much as 30 deg in a few yards. It is chiefly 
developed in the neighbourhood of Portland and Bridgewater, 
but does not extend far inland, so that either the causes producing 
it have not operated for any lengthened period, or else the 
previously formed rock has been entirely removed. 
From Cape Bridgewater to the mouth of the Glenelg, and for a 
long distance farther west, the low coast line is occupied by dunes 
of shifting sand, which sometimes rise to a height of from 200 to 
300 feet. By examining these mounds, it is at once seen how the 
hardened rock of the cliff sections has been formed, as, wherever 
the wind has removed any considerable mass of sand from one of 
them, the remaining portion is found to be more or less consoli- 
dated. A little consideration will convince anyone that this 
result must be inevitably produced when a mound of sand, of the 
height mentioned, remains intact for any length of time. 
Since the dune limestone is thus due to causes still in active 
operation, I have classed it as Recent, though I am aware it has 
also been referred to the Pleistocene period. For aught anyone 
can say to the contrary, its deposition may have commenced in 
Pleistocene times, but, as represented by the indurated dunes of 
Swan Lake and the hummock region of Discovery Bay, the action 
appears to have continued ever since. 
One other deposit remains to be noticed. If I were asked to 
name the most striking feature of the plains bordering the Glenelg, 
and extending for many miles to the west and north, as well as 
for some distance to the east, I should certainly reply, ‘“‘ Sand,” 
and whoever travels much in the region must have the same 
conclusion forced upon him. Sometimes one has to plod slowly 
along through sandy and almost desert tracts for fully forty miles 
at a stretch. It is true there are occasional swamps and morasses, 
but the tame monotony of the landscape is not thereby much 
relieved. 
* “The Hawkesbury Sandstone.” Roy. Soc. V.S.W., 1883. 
*o2 
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