46 
RECORDS OF THE AUSTRALIAN MUSEUM. 
GEOLOGICAL and ETHNOLOGICAL OBSERVATIONS 
made in the VALLEY of the WOLLONDILLY RIVER, 
at its JUNCTION with the NATTAI RIVER, 
COUNTIES CAMDEN and WESTMORELAND. 
By R. Etheridge, Junr., Paleontologist. 
[Plates XII., XIII.] 
The following observations were made during a short visit, in 
company with Mr. W. A. Cuneo, Station-master at Thirlmere, to 
the junction of the Wollondilly and Nattai Rivers, to further 
examine some interesting phenomena noticed during a previous 
visit by the latter gentleman. The localities in question form a 
portion of the district of Burragorang, “ a local name for that 
part of the Wollondilly valley which occurs between the junction 
of the Nattai and the Cox with the forme-r river,”* 
The Wollondilly Gorge is about twenty miles from Thirlmere, 
and the descent into the valley commences at the highest point 
of the route, known as “The Mountain,” or in the Aboriginal 
language as Queahgong. This point is 1,900 feet above sea-level 
(approximately)! and the descent, by a magnificently engineered 
although most costly zig-zag road, is very rapid and steep ; and 
the river being itself only about one hundred and fifty feet above 
the sea, this allows of a fall on the road of at least 1,700 feet. 
Queahgong, as the crow flies, is only one and a quarter miles 
from the Nattai junction. 
Both the Wollondilly and the Nattai have cut deep gorges 
through the Hawkesbury Sandstone, into the Coal-measures and 
Upper Marine beds of the Premo-Carboniferous beneath it. The 
Hawkesbury Sandstone forms a perpendicular face of rock, a 
sharp escarpment in fact, whilst the united Coal-measures and 
Upper Marine present a fine slope down to the alluvial flats, 
in places bordering the river. By the combination of these 
443. 
*W. B. Clarke, Quart. Journ. Geol. Soc., 18G6, xxn., p. 
f The late Rev. W. B. Clarke gave the height of the highest point in 
his section ot Burragorang as 1,996 feet, but I do not think it was taken 
exactly at this spot. (See Sed. Form. N. S. Wales. 4th edit., 1878, 2nd 
section). 9 9 ^ 
