158 Proceedings of the Royal Society of Victoria. 



The sections shown by the aforementioned road cuttings are 

 of interest, especially that on the eastern side of the river. 

 Taking that one — which is some 420 feet long — in detail, we 

 find the following succession, commencing at the eastern end : — 

 A. — Red and greyish-red soil with small pieces of decom- 

 posing basalt, and masses of greyish-white carbonates 

 of lime and magnesia. This has a basin-shaped 

 appearance, taking the section between the surface 

 and the slope of the road, and in the middle is 

 about 5 feet thick, gradually tapering oif to the 

 surface as traced west, and overlying B. Its length 

 is about 60 feet. 

 B. — Dense and partly vesicular dark bluish basalt, full of 

 blebs and patches of carbonate of lime. The rock 

 is considerably jointed, changing, in the lower part, 

 into laminated and nodular basalt. The material in 

 the interstices and portions between the nodules is 

 quite decomposed. This basalt is about 14 feet 

 thick in the thickest part, and extends for about 

 150 feet along the cutting, terminating steeply near 

 its western end, thus overlying C for nearly the 

 whole way. 

 C. — Very vesicular basalt, weathering in a ragged semi- 

 columnar manner, and greatly jointed, quite different 

 in general appearance from the laminated structure 

 of the immediately overlying basalt. It shows a 

 length of about 210 feet, sloping off very gradually 

 on the east, but more steeply on the west. It is 

 about 6 feet thick in the middle. 

 The basalt in this section seems to have been derived from 

 Mount Mary, and consists of at least two flows. The old surface 

 of C appears to have been a very irregular one, probably due to 

 unequal cooling of the surface of the flow, and the jutting 

 prominences of ragged blocks torn from the parent mass. 



In one or two places there are pieces of C wedged in situ into 

 the lower portion of B. At the western end of the cutting the 

 lower portion of B consists of a band of dense dark blue basalt, 

 the upper portion of decomposing nodular and laminated basalt. 



