44 INAUGURAL ADDRESS. 



the depressed area into a vast fresh-water sea, to be followed in 

 our own time by utter desiccation. The unconformity of the Desert 

 Sandstone to the Lower Cretaceous of the country about the River 

 Flinders induced Daintree, in 1872, to regard it as Tertiary, but he 

 expressed no opinion as to the conditions of deposition of this 

 widespread formation, which " did at one time cover nearly the 

 whole of Australia;" but Mr, Etheridge * thought that the series 

 was probably fresh water. The Rev. Tenisou Woods f held that 

 the Desert Sandstone was of seolian origin, and had even suggested 

 that it was contemporaneous with the Hawkesbury Sandstone — both 

 views being quite untenable. The Desert Sandstone has since been 

 found to contain, near Cooktown, interstratifi cations of coal, and at 

 Croydon marine fossils ; and Mr. JackJ concludes that after the 

 Rolling Downs formation (Lower Cretaceous) had been laid down in 

 the comparatively naiTow sea which connected the Gulf of Carpen- 

 taria with the Great Australian Bight, and converted the Australian 

 area into two islands, a considerable upheaval took place. The 

 denudation of the Lower Cretaceous followed ; unequal movements 

 of depression then brought about lacustrine conditions on portions 

 of the now uplifted bottom of the old deep sea strait, and in other 

 portions permitted of the admission of the waters of the ocean. 

 Finally a general upheaval placed the deposits of the period just 

 ■concluded in nearly the positions in which we now find them. 



A subject of great interest in this connection is the age of the 

 Desert Tableland of Xorth and North-west Australia. Its struc- 

 ture has been well described by King (1826), Grey (1841), Stokes 

 (1846), Jukes (1850), F. Gregory (1861), and' Goyder, A. C. 

 (1869). Its massive sandstones are represented by Jukes as of 

 xinknown age, but are svipposed by him to be Palaeozoic. Wilson, of 

 Gregory's expedition, places them on the horizon of the Hawkesbury 

 Sandstone. Hardman's description of the country from King Sound 

 to the Leopold Range recalls that of Grey's, respecting the country 

 adjacent to Hanover Bay, and in all probability the Carbonifex'ous 

 sandstone of Hardman extends thus far north. The charac- 

 teristics of the quartzites of the Leopold Range are not applicable 

 to the tableland sandstone of the Lower Victoria River, or of 

 Aruheim's Land. If we approach these areas from the eastward 

 there is much reason for the belief that the (tableland) sandstone 

 is coterminous with the Desert Sandstone ; this view was held by 

 Tate§ and Tenison Woods||. The fossililerous pebbles found by 



• Quart. Journ. Geol. Soc, vol. xxvin., p. 3i'4, lHr2. 



t Proc. Roy. Soc. N. S. Wales, 1882. i Geology of Queensland, 1892, p. 511 



i Pari. Paper, S.A., No. 63, 1882. || Pari. Paper, S.A., No. 122, 1886. 



