NOTES ON GLACIAL PHENOMENA ABOUT MOUNT 
GAMBIER. 
By Pe Hi. PRinstiny 
(Communicated by Prof. Tate). 
[Read September 6, 1892.] 
ABRIDGED. 
One of the most striking and persistent geological features is a 
stratum of sand, which overlies the limestone of the district. 
Round Naracoorte are sand-dunes sometimes attaining thirty and 
forty feet high; these continue intermittently along the high 
ground through Penola to Mount Gambier. This tract seems to 
be the watershed of the South-East ; spreading away to the west 
are the Mosquito Plains and the swampy lands of Lucindale and 
Millicent ; on the east are sandy ridges and small sandy flats 
which stretch disjointedly to the western districts of Victoria. 
On the western side sand is not so frequent, although great 
patches occur, as from Mount Gambier to Tantanoola ; on the 
south of Mount Gambier the watershed terminates, and slopes to 
the sea. 
The origin of this sand is not so clear as would appear at first 
sight ; that it is partly of marine origin is proved by the presence 
of existing sea-shells in it, as may be gathered by reference to 
Tenison-Woods’ “ Notes on the Geology of 8S. A.” It is in the 
immediate vicinity of Mount Gambier, however, that the clue is 
to be found. 
At any one of the numerous quarries close to Mount Gambier, 
a number of pot-holes in the limestone may be seen in the face ; 
these vary in width from one to five and six feet, and in depth up 
to ten feet; they are filled, some with the surrounding soil, 
others with clay (a greenish-gray predominating), interspersed 
with angular and rounded rock-fragments of various sizes up to 
two pounds in weight. ‘The angular fragments have their edges 
as fresh as when tirst broken off the parent rock, and the rounded 
ones present the appearance of having been well-rolled by water. 
Beneath the volcanic-tuff, the sand-layer ranges from a few to 
eighteen or twenty inches in thickness ; it appears, to a great 
extent, to be angular, although containing a proportion of rounded 
grains, and at the same time contains a great number of edged 
fragments weighing up to a quarter of a pound, and rolled pieces 
of like size ; when sufficiently thick, as at an old well about two 
