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Art. VI I. — Further Note on the Glacial Deposits of 

 Bacchus Ularsh. 



By Graham Officer, B.Sc, and Lewis Balfour, B.A. 



[Eead 8th June, 1803.] 



The immediate object of the present note is to correct a 

 mistake in our investigations of the Bacchus Marsh glacial 

 deposits, the results of which were embodied in a paper read 

 before this Society last year. In that paper we claimed to have 

 shown that there were two distinct tills at Bacchus Marsh, 

 separated by the so-called Bacchus Marsh sandstones, and that 

 the upper of these rested on the denuded sui^face of the sandstone. 

 It is to the latter point that we desire to draw attention. 



Our conclusions in this respect were principally drawn from 

 the consideration of sections at a small quarry on the Korku- 

 pen-imul Creek. "VVe here described till overlying the sandstone, 

 and a granite boulder over a yard in diameter together with an 

 accumulation of smaller erratics as being jammed into the broken 

 surface of the sandstone. 



Having since travei'sed a good deal more ground without 

 seeing any further evidence of such a state of things, we investi- 

 gated the matter further, with the result that we now find that 

 the supposed till ovei'lying the denuded sandstone is really a 

 "wash," containing striated stones, and derived in part, at least, 

 from an outcrop of a deposit a little above the quarry. The 

 broken sandstone is due to weathering and a certain amount of rock 

 movement. The granite boulders lie embedded in a matrix of 

 clay which is really intercalated with the sandstones, but looking 

 very much at first sight as if subsequently injected. There are 

 several thin clay bands besides this running through the sandstone, 

 and in these bands small stones of the kinds met with in the till 

 occur. Several we found bore glacial strise. One of these stones was 

 six inches in diameter. About the line of junction of the largest 

 of these bands, both the sandstone and the clay are remarkably 



