122 RESEARCH COMMITTEES. 
BALD HILLS AND YANKALILLA. 
Followed the crest of the Bald Hills on north side of the public 
road and observed granitic and other erratics scattered over the 
fields of Mr. J. R. Kelly, M.P., at Cornhill, and picked up strongly- 
glaciated quartz pebble near the source of the Inman, a little 
above the Bald Hills post-ottice. 
On the western slopes of the Bald Hills watershed, erratics are 
common, especially in the tributaries of the Bungala River. Near 
the fourth milepost from Yankalilla, 6 miles from Normanville, 
there is a conspicuous face of drift on Mr. Capper’s ground, seen 
from the road on the south bank of the creck near the house. 
The section is about 200 yards long by 15 feet high, and consists 
of soft, yellowish sandstone, studded with numerous erratics. 
By far the largest and most interesting exposure of the glacial 
beds of the neighbourhood i is seen in Wood’s Creek, about a mile 
from the centre of the township of Yankalilla, and a few hundred 
yards above the junction which the creek makes with the Bungala 
River. For many years this stone has been worked as “the 
Government quarry” for making and metalling the roads, the 
quarry face extending 150 yards laterally, and has exposed a 
thickness of stone of over 50 feet from the bed of the creek to 
the top of the quarry. The stone is a white, yellow, and grey 
sandstone, decomposing into loose sand near the surface, but, at 
depth, passes into a compact grit. The bedding is a little uncer- 
tain. On one side of the quarry, what appeared to be bedding 
planes with a rolling curvature dipped towards the creek at an 
angle of 20° N.N.W. The stone is conspicuously jointed both 
vertically and obliquely, and where compact can only be won by 
blasting. The bed is crowded with erratics of great variety, but 
on account of the intimate union between the included stones and 
the matrix, sometimes they can only be recognised by a close 
examination of the face. Granite (of Port Victor type) is the 
most common. One example of this kind was exposed on the 
quarry face that gave the measurement 18 in. x 10in. Others 
exhibited opalescent quartz as a constituent exactly corresponding 
to a variety found at Port Elliot. Amongst the erratics were 
also noticed mica schist, different coloured quartzites, quartz 
pebbles, crystals of orthoclase, &e. The granite and schists have 
undergone considerable decomposition, but most of the quartzites 
and quartz pebbles retain striking evidences of glaciation. The 
finer material consists of quartz sand, mostly rounded, strangely 
intermixed as to size, whilst the cementing agent is apparently a 
silicate resembling pipeclay, possibly the product of the grinding 
down of the orthoclase of the granitic rocks. The junction between 
the glacial beds and the older rocks is clearly exposed in the creek, 
where the former are seen to rest unconformably on dark-coloured 
