Tboc. Roy. Soc. Victoria, 22 (N.S.), Pt. IT., 1909.] 



Art. XIX. — On the Bacchus Marsh Sandstones 

 and their Fossils. 



Bv G. B. PRITCHARD, B.Sc, F.G.S., 



Lecturer in Geolotry, etc., Woi-kin^ Men's College, Melbourne. 



[Read 9th December, 1909.] 



The Bacchus Marsh Sandstones are perhaps as well known as 

 any series of rocks in the State of Victoria, not only to Aus- 

 tralians, but to geologists generally in other parts of the world. 

 This no doubt is due to the many diverse points of interest 

 which have from time to time been connected with these de- 

 posits, and many who are not geologists are familiar with the 

 name from different standpoints. In the first place, we may 

 notice that this stone was opened up and quarried to a con- 

 siderable extent for the purpose of a building stone. Some- 

 where about the years 1845 to 1847 the possibilities of this 

 stone as a building stone were first considered, and local use 

 was made of it for several years. Then a Government reward 

 for a building stone within a reasonable distance for certain 

 public buildings in Melbourne, led to a much more extensive 

 quarry being opened, and stone was supplied for the following : 

 — The Treasury, the old Custom House, the Crown Lands Selec- 

 tion Office, the Parliament House Library, and several others. 



The stone was not easily obtained, as the over-burden of 

 weathered material was regarded as too great, the jointing was 

 not of a too favourable character, and the deeper excavations 

 failed to yield a stone of uniform colour ; in fact, the colour 

 variations, such as concretionary banding, ultimately proved 

 too much for the Melbourne architects. 



In the light of our present knowledge it seems remarkable 

 that such a stone should ever have been recommended, for in 

 many respects evidence is not lacking to prove unsuitability. 

 The association of a peculiar conglomerate with these sandstones 

 was early recognised by Mr. A. R. C. Selwyn, as probably point- 



