176 Proceedings of the Royal Society of Victoria. 



We may notice also that in the Daylesford cuttings joints- 

 occasionally show a somewhat wavy surface in sandstone (in 

 slate they are much smoother) and that there is a slight rippling 

 of the surface of the pockets at Italian Hill. 



A consideration of the effect of the crumpling on the junction 

 of two dissimilar rocks will lead to the conclusion that it is 

 highly improbable that such a sui'face, if originally even, should 

 remain so at any place when packing has taken place in one of 

 the rocks, and the inequalities would be likely to assume some 

 linear arrangement, as the folds within the crumpled bed do. 

 The fact that the main ridges of the apparent ripple marks at 

 Italian Hill are nearly parallel to the strike agrees with this. 



At Daylesford, Bendigo and Chewton, and probably at most 

 other places, in the Ordovician rocks in Victoria the evidence 

 of movements and packing in the slates is so definite and wide- 

 spread that the existence of apparent ripple marking has an 

 adequate explanation in tliis, and is, at least, no evidence of 

 original ripple marking. 



The pockets in tlie sandstone at Italian Hill do not appear to 

 be a common feature. They can be seen also in the by-wash 

 of the Lake, where some might at first sight be mistaken 

 for potholes, but their form is easily recognised and they are 

 revealed by slight slipping in the solid bank. They are probably 

 in the same beds as appear in the cutting. They are also seen 

 at the north end of Leveret's cutting and at the Breakneck, 

 north of Hepburn, and possibly at Ohewton. 



It is possible for sand to be deposited with an extremely 

 uneven surface in rough water (as I noticed in sludge from 

 sluicing deposited among rocks in Jim Crow Creek), but here 

 there is no evidence of such currents and the edges of the 

 pockets are too definite. The band of slate fragments filling 

 some of them suggests that they are the hollows which have 

 once been occupied by the fragmentary remnants of a squeezed- 

 out slate bed, but others contain sandstone and are not on any 

 evident line of a slate bed. If, however, a slate bed were to be 

 squeezed into isolated patches the neighbouring sandstones being 

 at places in contact this would tend to the production of very 

 irregularly distributed strains in the sandstone, and hence might 

 set up irregular curved fractures and irregular consolidation. 



