216 



the deposition of the Tertiaries)^ have been preserved from the 

 effects of denudation by thick horizontal beds since the beginning 

 of the Tertiary period. 



The presence of rocks of intermediate age in Western Victoria 

 is suggestive of the possibility of their extension under the great 

 Tertiary plains of the Murray, whilst the existence of numerous 

 inliers of granite, running in a line from the Murray Bridge to 

 the Victorian border, may mark the course of an old ridge of 

 Archajan rocks that acted as a barrier to the force of the sea, limit- 

 ing the power of marine denudation in its effects upon the country 

 lying to the north and east of this line. Provided the coal 

 measures were deposited in the old arch^ean valley of the 

 Murray, a barrier to seaward, such as that indicated, must have 

 proved an important physical feature in favour of their preserva- 

 tion. 



The conclusions, so far as they can be stated in relation to this 

 interesting question, are as follows : — 1. The presence of coal 

 detritus in alluvial beds of an undisturbed character within the 

 Murray basin cannot be doubted. 2. The carbonaceous frag- 

 ments are not proper to the bed in which they are found ; their 

 lithological character and subangular shape prove them to be 

 transported material dislodged from formations of an older date. 

 3. If the clay-bed in which the coal drift occurs be of Older Ter- 

 tiary age (as supposed), it is extremely improbable that the frag- 

 ments in question, which were highly mineralised when first 

 Avashed into their present position, could be of so recent an age 

 as Tertiary. 4. The proximity of rocks of coal-bearing age in 

 Victoria, on the eastern boundaries of the great tertiary plain, 

 points to a probable extension of these formations to the west- 

 ward. 5. No hypothesis that would account for the presence of 

 coal-wash in such a position is credible, except the supposition 

 that these fragments have been derived from rocks of a like 

 character in situ, which probably occur in patches of greater or 

 less extent beneath the superficial formations, and will probably 

 be found at no great distance from the spot where the first 

 indications have been discovered. 6. So far as can be judged 

 from small and somewhat weathered specimens, the coal, if 

 found, is likely to be of commercial value should it occur in 

 sufficient quantities. 



