Proceedinr/s of ihc Ro/jal tiodefij of Vhdovla. 199 



[iroving that a very careful investigation of the strata thereabouts 

 liad been made. He was struck with the large amount of erosion 

 that had occurred in the valley, which was evidently the bed 

 of an old extension of Bass Straits. More knowledge was 

 gradually being gained of the extension of this old arm of the sea, 

 and it was quite evident from what was known, that a Strait 

 once existed between the Otway Ranges and the Main Dividing 

 Mange. The Otwa}^ Ranges for many ages must have constituted 

 ■.n\ island in the Straits, about 70 miles long and perhaps 30 

 wide. There was a considerable amount of identity between the 

 deposits all over the district. The limestone found there, 

 specimens of which had been shown that evening, was very 

 similar in its general character to that found so far away to the 

 west as Portland. Beautiful white cliffs similar to those of 

 Dover, and also lava, could be seen there. There is no doubt 

 that the Strait was a very wide one, and the bores and shafts put 

 down showed that there were narrow channels leading from the 

 sea. Some miles to the west of Steiglitz mountainous country 

 existed, and the river had cut its passage, not through the 

 tertiary beds as described that evening, but througli the 

 immensely old^r Silurian. These ancient Silurian valleys that 

 liad been cut by the old Moorabool were immensely deeper than 

 the valleys of the present day. They had been filled up 

 gradually by the sedimentary beds in the same manner as the 

 Strait itself in the course of ages was filled up. In the 

 Moorabool Valley, in the neighbourhood to which he was 

 referring, Pliocene lava was seen on the surface. Beneath that 

 there was sand and gravel and the auriferous wash of the miner. 

 Sinking still further through the shallow level strata, a bed of 

 coralline limestone 13 feet thick was reached. That bed being 

 organic, grew at the time when the whole countiy was 

 considerably lower than it is to-day ; when, in fact, the sea ran 

 up the valley of the Moorabool and when the Moorabool itself 

 was a little creek that had its sea mouth probably many miles 

 further to the north of the section to which he was referring. 

 Below the coi-alline limestone there was more sandstone, and 

 below that again another layer of lava. It was not a solid 

 bed of lava, as it consisted of a series of thin layers of basalt. 

 Between those layers were sandwiched more layers of the 

 coralline limestone. Between these beds, but lower down the 

 stream, there were very thick beds 60 or 70 feet thick of 

 what the miners term " cement "---sandstone containing quartz 

 boulders. Then there was a false bottom carrying a lot of gold, 

 and below that again there was another bed 30 or 40 feet thick 

 of a different character. It seemed to him that the character of 

 those two beds indicated the climate during the early tertiaiy 

 period was very different to that of the present time. We 



p 2 



