126 
Bacchus Marsh. The Geological Survey laboratory made up a sample 
(Assay ISTo. 499) into test pieces^ and burned them, with the following 
results:— 
— 
Test Piece. 
Conditions after Test. 
Shrinkag'e per Cent. 
Colour. 
Hardness, &c. 
0 
Air dried 
4 
White 
Firm hard tile 
A 
1100° C 
8 
White 
Cracked 
B & C 
1340° C 
22 
Blue 
Vitrified 
The laboratory summarizes this test as follows:—The shrinkage is 
high and the amount of fluxing material present causes vitriflcation at 
a high temperature. The clay is of no value by itself, hut if existing in 
large quantity could be used with other materials as a clay body.’’ 
The dyke, however, is only about a foot wide, and unless larger 
dykes of similar material exist in the vicinity its value would be mini¬ 
mized. 
Samples of magnesian limestone (dolomite) were collected at the 
quarries of Messrs. Alkemade and Burnip, at Coimadai. This lime¬ 
stone, though high in magnesia, makes a hard and durable hydraulic 
mortar. The lime is sold according to the following standard:— 
per cent. 
Lime carbonate . . 
. . 55.00 
Magnesian carbonate 
. . 41.00 
Silica and alumina 
2.05 
Iron oxide 
1.90 
Water, &;c. 
.05 
Mr. Alkemade presented a few fossil bones to the Department, also 
a piece of ostracodal limestone. Samples of soils formed from the 
decomposition of Lower Ordovician strata, Bacchus Marsh sandstone, 
glacial conglomerate, and soils were collected. 
[30.8.13.] 
THE GEOLOGY OF THE PABISHES OF PARWAH 
AHD MOORADORAHOOK. 
By W. II. Ferguson, Assistant Field Geologist. 
General. 
This report deals with a geological and topographical survey of 
an area of about 20 square miles in the parishes of Parwan and Moora- 
doranook, county of Grant, Bacchus Marsh district. The area is 
situated south of the Werribee River, and is crossed by the Melbourne 
to Bacchus Marsh railway. Parwan, the nearest railway station, is 
just outside the western boundary. It i§' 29 miles from Melbourne, and 
464 ft. above sea-level. The country consists of a basaltic tableland, 
much of which is from 400 ft. to 500 ft. above sea-level. 
The principal natural feature is the Werribee River, which bounds 
the survey on the north and east. 
The tableland has been built up of layers of sands, gravels, &c., 
interbedded with flows of basalt, both of Tertiary age; it extends beyond 
